About 1,500 years ago a fortress that is now called “Sandby borg” came under a surprise attack. Archaeologists found that the inhabitants were slaughtered, many of them didn’t even have the chance to face their attackers. This picture shows the skeleton of a teenager who fell backward over a dead or dying adult. The house where these two were found has at least nine dead individuals. [Read more about the ancient massacre site]
Unexpected event
Credit: Kalmar County Museum
This teenager was found at Sandby borg in the house where at least nine people were killed suddenly. The skeleton of half a herring suggests that the people in this house were eating when they were attacked.
Treasured items
Credit: Daniel Lindskog
Some fantastic jewelry has also been discovered at Sandby borg. This photograph shows jewelry found in the house where at least nine people were killed. A brooch along with glass beads, rings and other forms of jewelry were discovered. Four deposits of jewelry were found in other locations at Sandby borg.
Wealthy victims
Credit: Daniel Lindskog
Five gilded brooches that were found in five different hidden deposits at Sandby borg. Made of silver and gilded with gold archaeologists believe that they belonged to aristocratic women.
Evidence of time
Credit: Daniel Lindskog
More of the jewelry discovered at Sandby borg. At left is a glass sword bead. At center is a gold coin showing Roman Emperor Valentinian III (reign 425-455) and at right is a gilded sword pendant.
Desecrated and deserted
Credit: Kalmar County Museum
A plan of Sandby borg. 53 structures are surrounded by a wall that is four to five meters (13 feet to 16 feet) high and has three gates. The site was abandoned after the attack, the dead were not even buried.
Uncovering history
Credit: Sebastian Jakobsson
This photograph shows “house 4” being excavated. It is located beside the walls of the fortress.
Dental plaque is a buildup of bacteria on the surface of teeth.
Credit: Lighthunter | Shutterstock
Biofilms are a collective of one or more types of microorganisms that can grow on many different surfaces. Microorganisms that form biofilms include bacteria, fungi and protists.
One common example of a biofilm dental plaque, a slimy buildup of bacteria that forms on the surfaces of teeth. Pond scum is another example. Biofilms have been found growing on minerals and metals. They have been found underwater, underground and above the ground. They can grow on plant tissues and animal tissues, and on implanted medical devices such as catheters and pacemakers.
Each of these distinct surfaces has a common defining feature: they are wet. These environments are “periodically or continuously suffused with water,” according to a 2007 article published in Microbe Magazine. Biofilms thrive upon moist or wet surfaces.
Biofilms have established themselves in such environments for a very long time. Fossil evidence of biofilms dates to about 3.25 billion years ago, according to a 2004 article published in the journal Nature Reviews Microbiology. For example, biofilms have been found in the 3.2 billion-year-old deep-sea hydrothermal rocks of the Pilbara Craton in Australia. Similar biofilms are found in hydrothermal environments such as hot springs and deep-sea vents.
This greenish-brown slime, found on rocks in a streambed, is a biofilm composed of algae.
Credit: USGS
Biofilm formation
Biofilm formation begins when free-floating microorganisms such as bacteria come in contact with an appropriate surface and begin to put down roots, so to speak. This first step of attachment occurs when the microorganisms produce a gooey substance known as an extracellular polymeric substance (EPS), according to the Center for Biofilm Engineering at Montana State University. An EPS is a network of sugars, proteins and nucleic acids (such as DNA). It enables the microorganisms in a biofilm to stick together.
Attachment is followed by a period of growth. Further layers of microorganisms and EPS build upon the first layers. Ultimately, they create a bulbous and complex 3D structure, according to the Center for Biofilm Engineering. Water channels crisscross biofilms and allow for the exchange of nutrients and waste products, according to the article in Microbe.
Multiple environmental conditions help determine the extent to which a biofilm grows. These factors also determine whether it is made of only a few layers of cells or significantly more. “It really depends on the biofilm,” said Robin Gerlach, a professor in the department of chemical and biological engineering at Montana State University-Bozeman. For instance, microorganisms that produce a large amount of EPS can grow into fairly thick biofilms even if they do not have access to a lot of nutrients, he said. On the other hand, for microorganisms that depend on oxygen, the amount available can limit how much they can grow. Another environmental factor is the concept of “shear stress.” “If you have a very high flow [of water] across a biofilm, like in a creek, the biofilm is usually fairly thin. If you have a biofilm in slow flowing water, like in a pond, it can become very thick,” Gerlach explained.
Finally, the cells within a biofilm can leave the fold and establish themselves on a new surface. Either a clump of cells breaks away, or individual cells burst out of the biofilm and seek out a new home. This latter process is known as “seeding dispersal,” according to the Center for Biofilm Engineering.
Why form a biofilm?
For microorganisms, living as a part of a biofilm comes with certain advantages. “Communities of microbes are usually more resilient to stress,” Gerlach told Live Science. Potential stressors include the lack of water, high or low pH, or the presence of substances toxic to microorganisms such as antibiotics, antimicrobials or heavy metals.
There are many possible explanations for the hardiness of biofilms. For example, the slimy EPS covering can act as a protective barrier. It can help prevent dehydration or act as a shield against ultraviolet (UV) light. Also, harmful substances such as antimicrobials, bleach or metals are either bound or neutralized when they come into contact with the EPS. Thus, they are diluted to concentrations that aren’t lethal well before they can reach various cells deep in the biofilm, according to a 2004 article in Nature Reviews Microbiology.
Still, it is possible for certain antibiotics to penetrate the EPS and make their way through a biofilm’s layers. Here, another protective mechanism can come into play: the presence of bacteria that are physiologically dormant. In order to work well, all antibiotics require some level of cellular activity. So, if bacteria are physiologically dormant to begin with, there is not much for an antibiotic to disrupt.
Another mode of protection against antibiotics is the presence of special bacterial cells known as “persisters.” Such bacteria do not divide and are resistant to many antibiotics. According to a 2010 article published in the journal Cold Spring Harbor Perspectives in Biology, “persisters” function by producing substances that block the targets of the antibiotics.
In general, microorganisms living together as a biofilm benefit from the presence of their various community members. Gerlach cited the example of autotrophic and heterotrophic microorganisms that live together in biofilms. Autotrophs, such as photosynthetic bacteria or algae, are able to produce their own food in the form of organic (carbon containing) material, while heterotrophs cannot produce their own food and require outside sources of carbon. “In these multi-organismal communities, they often cross feed,” he said.
Biofilms and us
Given the vast range of environments in which we encounter biofilms, it is no surprise that they affect many aspects of human life. Below are a few examples.
A scanning electron micrograph shows a biofilm formed by Candida albicans on an intravascular disc prepared from catheter material.
Credit: CDC
Health and disease
As research has progressed over the years, biofilms — bacterial and fungal — have been implicated in a variety of health conditions. In a 2002 call forgrant applications, the National Institutes of Health (NIH) noted that biofilms accounted “for over 80 percent of microbial infections in the body.”
Biofilms can grow on implanted medical devices such as prosthetic heart valves, joint prosthetics, catheters and pacemakers. This in turn leads to infections. The phenomenon was first noted in the 1980s when bacterial biofilms were found on intravenous catheters and pacemakers. Bacterial biofilms have also been known to cause infective endocarditis andpneumonia in those with cystic fibrosis, according to the 2004 article in Nature Reviews Microbiology, among other infections.
“The reason that biofilm formation is a great cause of concern is that, within a biofilm, bacteria are more resistant to antibiotics and other major disinfectants that you could use to control them,” said A.C. Matin, a professor of microbiology and immunology at Stanford University. In fact, when compared to free-floating bacteria, those growing as a biofilm can be up to 1,500 times more resistant to antibiotics and other biological and chemical agents, according to the article in Microbe. Matin described biofilm resistance combined with the general increase in antibiotic resistance among bacteria as a “double whammy” and a major challenge to treating infections.
Fungal biofilms can also cause infections by growing on implanted devices.Yeast species such as the members of the genus Candida grow on breast implants, pacemakers and prosthetic cardiac valves according to a 2014 article published in the journal Cold Spring Harbor Perspectives in Medicine. Candida species also grow on human body tissues, leading to diseases such as vaginitis (inflammation of the vagina) and oropharyngeal candidiasis (a yeast infection that develops in the mouth or throat). However, the authors note that drug resistance was not shown in these instances.
Bioremediation
Sometimes, biofilms are useful. “Bioremediation, in general, is the use of living organisms, or their products — for example, enzymes — to treat or degrade harmful compounds,” Gerlach said. He noted that biofilms are used in treating wastewater, heavy metal contaminants such as chromate, explosives such as TNT and radioactive substances such as uranium. “Microbes can either degrade them, or change their mobility or their toxic state and therefore make them less harmful to the environment and to humans,” he said.
Nitrification using biofilms is one form of wastewater treatment. During nitrification, ammonia is converted to nitrites and nitrates throughoxidation. This can be done by autotrophic bacteria, which grow as biofilms on plastic surfaces, according to a 2013 article published in the journal Water Research. These plastic surfaces are just a few centimeters in size and distributed all through the water.
The explosive TNT (2,4,6-Trinitrotoluene) is considered a soil, surface water and groundwater pollutant. The chemical structure of TNT consists of benzene (a hexagonal aromatic ring made of six carbon atoms) attached to three nitro groups (NO2) and one methyl group (CH3). Microorganisms degrade TNT by reduction, according to a 2007 article published in the journal Applied and Environmental Microbiology. Most microorganisms reduce the three nitro groups, while some attack the aromatic ring. The researchers — Ayrat Ziganshin, Robin Gerlach and colleagues — found that the yeast strain Yarrowia lipolytica was able to degrade TNT by both methods, though primarily by attacking the aromatic ring.
Microbial fuel cells
Microbial fuel cells use bacteria to convert organic waste into electricity. The microbes live on the surface of an electrode and transfer electrons onto it, ultimately creating a current, Gerlach said. A 2011 article published in Illumin, an online magazine of the University of Southern California, notes that bacteria powering microbial fuel cells break down food and bodily wastes. This provides a low-cost source of power and clean sustainable energy.
Ongoing research
Our world is teeming with biofilms. In fact, by the mid-20th century, more bacteria were found on the inside surfaces of containers holding bacterial cultures, than floating freely in the liquid culture itself, according to the 2004 article in Nature Reviews Microbiology. Understanding these complex microbial structures is an active area of research.
“Biofilms are amazing communities. Some people have compared them to multicellular organisms because there is a lot of interaction between single cells,” Gerlach said. “We are continuing to learn about them, and we are continuing to learn about how to control them better; both for reduced detriment, as in the field of medicine, or for increased benefit as in bioremediation. We are not going to run out of interesting questions in that area.”
At Live Science, we delve into science news from around the world every day — and some of those stories can get a little weird. Here are some of the strangest science news articles from this week.
Uranus smells terrible
Methane in the atmosphere gives Uranus its blue hue, as seen in this image from the Keck telescope from 2004.
Credit: Lawrence Sromovsky, University of Wisconsin/W. M. Keck Observatory
In case you were wondering, Uranus smells like farts. A new study found that the seventh planet from the sun has an upper atmosphere filled with hydrogen sulfide. This makes Uranus different from the gas giants Jupiter and Saturn, which have more ammonia in their upper atmospheres. [Read more about Uranus’ smell]
Fake asteroid
Scientists at Brown University built an indoor asteroid cannon to see what might happen if one of these space rocks were to collide with Earth. During several trials, the researchers blasted the fake asteroid into a fake Earth at speeds “comparable to the median impact speed” in the asteroid belt, they wrote in a study. [Read more about the fake asteroid cannon]
Giant ground sloth
An artist’s interpretation of how the sloth likely flailed its arms around to protect itself against the human hunters.
Credit: Alex McClelland/Bournemouth University
About 11,000 years ago, ancient humans followed a giant ground sloth, stepping in the tracks of its clawed paws. These track marks are now fossilized and indicate that the humans once interacted with — and possibly hunted — these now-extinct towering sloths in what is now New Mexico. [Read more about the fossilized footprints]
Shiny foil
Could anyone transform a foil ball into a shiny metal sphere? Sure — if you have the right tools, and a lot of patience.
Credit: Seamster/Instructables.com/CC by 2.5
In a new internet trend, videos show crumpled aluminum foil balls transforming into beautifully smooth and highly polished spheres. But how do the people convert these ugly balls into stunning globes? Live Science looked into it and found that the technique has similarities with Japanese samurai sword making. [Read more about the aluminum foil spheres]
Sneaky ants
This parasitic ant, called Megalomyrmex symmetochus, crashes colonies of fungus-farming ants (Sericomyrmex amabilis), eating their crops and killing their babies.
Credit: David Nash, courtesy of The Ohio State University
A sneaky, parasitic ant uses chemical warfare to get a free meal and home. This Central American ant has a potent venom that can scare off invaders. And even though this ant eats baby ants, it’s still accepted into the homes of certain ants that use it as a guard dog. [Read more about the sneaky ants]
Human bone daggers
A human bone dagger (top) from New Guinea and a cassowary bone dagger (bottom), attributed to the Abelam people of New Guinea
Credit: Copyright Hood Museum of Art/Dartmouth College; Dominy NJ. et al, Royal Society Open Science
The warriors of New Guinea used to carve daggers out of two unusual thighbones — those from humans and others from flightless, dinosaur-like birds called cassowaries. But which dagger was better? A new analysis shows that the human-bone daggers were stronger, largely because of the way they were carved. [Read more about the bone daggers]
Key injury
A brain scan shows a key lodged about 1.5 inches into a man’s brain.
Credit: Goal Post Media/SWNS
A 19-year-old man in India got into a brawl and ended up with a key embedded 1.5 inches (3.8 centimeters) into his skull. So, how did he survive? Luckily, the key didn’t cause internal bleeding or any damage to his brain, doctors said. [Read more about the key injury]
Want more weird science news and discoveries? Check out these and other “Strange News” stories on Live Science!
Deadly Fungus Cells Talk Amongst Themselves to Infect You Better
By Rachael Rettner, Senior Writer |
Electron microscopy images of spores of the deadly new VGIIc strain of the fungus Cryptococcus gattii.
Credit: Edmond Byrnes III, Joseph Heitman, Duke Dept. of Molecular Genetics and Microbiology
The idea of microbes joining forces inside your body to wreak havoc and cause disease sounds frightening — and it should. Now, scientists have found that a particular type of fungus does just that, and the fungal cells use a surprising method to team up and communicate with each other.
What’s more, the findings may explain why this fungus can infect healthy people, a characteristic that’s unusual for fungal infections, which more typically strike people with weakened immune systems.
The study focused on a fungus called Cryptococcus gattii, which lives in soil and is found mostly in tropical and subtropical regions. However, in 1999, a strain of this fungus popped up in British Columbia, Canada, and later, in Oregon and Washington state, mostly causing infections in otherwise-healthy people.
The infection, which people catch by inhaling fungal spores, can be life-threatening, causing a pneumonia-like illness in the lungs, as well as serious infections of the brain and tissues surrounding the brain and spinal cord. From 2004 to 2010, there were 60 reported causes ofCryptococcus gattii in the U.S., and among the 45 cases with known outcomes, nine (20 percent) died from their infections, according to a 2010 study from researchers at the Centers for Disease Control and Prevention.
Previously, researchers found that Cryptococcus gattii was so virulent because it had the “remarkable ability to grow rapidly within human white blood cells,” study author Ewa Bielska, a postdoctoral research fellow at the University of Birmingham in the United Kingdom, said in a statement. In 2014, Bielska’s colleagues found that this rapid growth resulted from a “division of labor,” meaning that the fungal cells worked together to coordinate their behavior and drive rapid growth. [10 Bizarre Diseases You Can Get Outdoors]
In the new study, Bielska and colleagues figured out exactly how the fungal cells are joining forces: The microbes use microscopic, fluid-filled sacs called extracellular vesicles to communicate.
“These vesicles act like ‘carrier pigeons,’ transferring messages between the fungi and helping them to coordinate their attack on the host cell,” said study senior author Robin May, director of the University of Birmingham’s Institute of Microbiology and Infection.
This is the first time that scientists have found a connection between extracellular vesicles and fungal virulence, the researchers said.
The scientists also found that, surprisingly, the fungal cells could use extracellular vesicles to communicate across relatively long distances between cells.
“Our initial expectation was that the fungus would only be able to communicate within a single host cell, but in fact we discovered that it can communicate over very large — in microbiology terms — distances and across multiple host cell barriers,” May said.
The findings “provides us with a potential opportunity to develop new drugs that work by interrupting this communication route during an infection,” he said.
The study was published April 19 in the journal Nature Communications.
The ‘End of the World’ Is Today. Here’s Why We’re Still Here.
By Jeanna Bryner, Live Science Managing Editor |
Enjoy your day.
Credit: G. Baden/Corbis via Getty Images
Today is the day.
It’s the beginning of the end, according to practiced doomsday diviner David Meade. On April 23, 2018, Meade says, the sun, the moon and Jupiter will line up in the constellation Virgo (in actuality, they will not be in that constellation) — an alignment that has biblical disaster written all over it.
In the Bible, Revelation 12:1-2 speaks of a “woman clothed with the sun, with the moon under her feet and a crown of twelve stars on her head,” who labors to give birth to a dictator who will ultimately bring about the world’s end.
Meade did a lot of numerical and cosmic gymnastics to come up with today’s apocalypse — one that, of course, will not come to be.
The same passage used for today’s prediction was also the basis for Meade’s end-of-the-world prediction last year, when he said the sky would essentially fall on Sept. 23. It did not. [End of the World? Top 10 Doomsday Threats]
And, in fact, his current forecast seems to have long roots: Baptist preacher William Miller made multiple failed doomsday predictions, and one of them was for April 23, 1843.
Sadly, perhaps for Meade, the planet Jupiter will appear not in Virgo but in the constellation Libra from Earth’s perspective; the sun will appear to align with Aries, while the moon will lurk in the constellation Gemini today,according to The Sky Live.
This celestial alignment is, according to Meade, just the beginning of the cosmic catastrophe. From there, a rogue planet called Planet X will supposedly pass by Earth in October and cause a planetwide mess (worldwide volcanic eruptions) that will culminate in the return of Jesus Christ — also based on the Book of Revelation.
There are a few problems with this part of the prediction. For one, Planet X, also called Nibiru, is fictional. And whereas scientists are looking for an Earth-size planet that they sometimes refer to as “Planet X” or “Planet Nine,” this is a different world altogether from the one described by Meade and others.
Nibiru, in fact, is the baby of conspiracy theorist Nancy Lieder, who floated the idea in the 1990s. This rogue planet — a body that astronomers who stare at the skies, looking for actual alien worlds, would not miss — was the basis for the failed 2012 Maya apocalypse, among others.
Besides Nibiru being a made-up world that has been debunked repeatedly, the Revelation passage also has some issues.
“The author of Revelation was wrong in his predictions, so neither this book nor any other ancient book is of much relevance for predicting the future,” Allen Kerkeslager, a professor of ancient and comparative religion at St. Joseph’s University in Philadelphia, told Live Science earlier this month.
All this is to say, the doomsday prediction is bogus. Happy Monday.
This new image shows the dramatic shape and colour of the Ring Nebula, otherwise known as Messier 57.
From Earth’s perspective, the nebula looks like a simple elliptical shape with a shaggy boundary. However, new observations combining existing ground-based data with new NASA/ESA Hubble Space Telescope data show that the nebula is shaped like a distorted doughnut. This doughnut has a rugby-ball-shaped region of lower-density material slotted into in its central “gap”, stretching towards and away from us.
Credit:
NASA, ESA, and C. Robert O’Dell (Vanderbilt University).
Hubble studies sequences of star formation in neighbouring galaxy
The NASA/ESA Hubble Space Telescope captures the iridescent tapestry of star birth in a neighbouring galaxy in this panoramic view of glowing gas, dark dust clouds, and young, hot stars. The star-forming region, catalogued as N11B lies in the Large Magellanic Cloud (LMC), located only 160,000 light-years from Earth. With its high resolution, the Hubble Space Telescope is able to view details of star formation in the LMC as easily as ground-based telescopes are able to observe stellar formation within our own Milky Way galaxy.
Our neighbourhood galaxy the Large Magellanic Cloud (LMC) lies in the Constellation of Dorado and is sprinkled with a number of regions harbouring recent and ongoing star formation. One of these star-forming region, N11B, is shown in this Hubble image. It is a subregion within a larger area of star formation called N11. N11 is the second largest star-forming region in LMC. It is only surpassed in the size and activity by “the king of stellar nurseries”, 30 Doradus, located at the opposite side of LMC.
Credit:
NASA/ESA and the Hubble Heritage Team (AURA/STScI/HEIC)
To celebrate its 24th year in orbit, the NASA/ESA Hubble Space Telescope has released this beautiful new image of part of NGC 2174, also known as the Monkey Head Nebula.
NGC 2174 lies about 6400 light-years away in the constellation of Orion (The Hunter). Hubble previously viewed this part of the sky back in 2011 — the colourful region is filled with young stars embedded within bright wisps of cosmic gas and dust.
This portion of the Monkey Head Nebula was imaged in the infrared using Hubble’s Wide Field Camera 3.
Credit:
NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Just weeks after NASA astronauts repaired the Hubble Space Telescope in December 1999, the Hubble Heritage Project snapped this picture of NGC 1999, a nebula in the constellation Orion. The Heritage astronomers, in collaboration with scientists in Texas and Ireland, used Hubble’s Wide Field Planetary Camera 2 (WFPC2) to obtain this colour image.
N44C is the designation for a region of ionized hydrogen gas surrounding an association of young stars in the Large Magellanic Cloud (LMC), a nearby, small companion galaxy to the Milky Way visible from the Southern Hemisphere. N44C is part of the larger N44 complex, which includes young, hot, massive stars, nebulae, and a ‘superbubble’ blown out by multiple supernova explosions.
Massive newborn stars are creating in this dramatic torn apart image of the Trifid Nebula.The Trifid Nebula is home to many thousands of newly created stars. The source of the jet is a young very hot star buried in the cloud.
This NASA/ESA Hubble Space Telescope image of the Trifid Nebula reveals a stellar nursery being torn apart by radiation from a nearby, massive star.
The picture also provides a peek at embryonic stars forming within an ill-fated cloud of dust and gas, which is destined to be eaten away by the glare from the massive neighbor.
This stellar activity is a beautiful example of how the life cycles of stars like our Sun is intimately connected with their more powerful siblings.
Credit:
NASA/ESA and Jeff Hester (Arizona State University)
This image shows a small section of the Veil Nebula, as it was observed by the NASA/ESA Hubble Space Telescope. This section of the outer shell of the famous supernova remnant is in a region known as NGC 6960 or — more colloquially — the Witch’s Broom Nebula.
The Twin Jet Nebula, or PN M2-9, is a striking example of a bipolar planetary nebula. Bipolar planetary nebulae are formed when the central object is not a single star, but a binary system, Studies have shown that the nebula’s size increases with time, and measurements of this rate of increase suggest that the stellar outburst that formed the lobes occurred just 1200 years ago.
This Hubble image shows RS Puppis, a type of variable star known as a Cepheid variable. As variable stars go, Cepheids have comparatively long periods — RS Puppis, for example, varies in brightness by almost a factor of five every 40 or so days.
RS Puppis is unusual; this variable star is shrouded by thick, dark clouds of dust enabling a phenomenon known as a light echo to be shown with stunning clarity.
These Hubble observations show the ethereal object embedded in its dusty environment, set against a dark sky filled with background galaxies.
Credit:
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration
Acknowledgment: H. Bond (STScI and Penn State University)
Composed of gas and dust, the pictured pillar resides in a tempestuous stellar nursery called the Carina Nebula, located 7500 light-years away in the southern constellation of Carina.
Taken in visible light, the image shows the tip of the three-light-year-long pillar, bathed in the glow of light from hot, massive stars off the top of the image. Scorching radiation and fast winds (streams of charged particles) from these stars are sculpting the pillar and causing new stars to form within it. Streamers of gas and dust can be seen flowing off the top of the structure.
Hubble’s Wide Field Camera 3 observed the Carina Nebula on 24-30 July 2009. WFC3 was installed aboard Hubble in May 2009 during Servicing Mission 4. The composite image was made from filters that isolate emission from iron, magnesium, oxygen, hydrogen and sulphur.
These Hubble observations of the Carina Nebula are part of the Hubble Servicing Mission 4 Early Release Observations.
This image from the NASA/ESA Hubble Space Telescope shows Sh 2-106, or S106 for short. This is a compact star forming region in the constellation Cygnus (The Swan). A newly-formed star called S106 IR is shrouded in dust at the centre of the image, and is responsible for the surrounding gas cloud’s hourglass-like shape and the turbulence visible within. Light from glowing hydrogen is coloured blue in this image.
This remarkable picture from the Advanced Camera for Surveys on the NASA/ESA Hubble Space Telescope shows one of the most perfect geometrical forms created in space. It captures the formation of an unusual pre-planetary nebula, known as IRAS 23166+1655, around the star LL Pegasi (also known as AFGL 3068) in the constellation of Pegasus (the Winged Horse).
The striking picture shows what appears to be a thin spiral pattern of astonishingly regularity winding around the star, which is itself hidden behind thick dust. The spiral pattern suggests a regular periodic origin for the nebula’s shape. The material forming the spiral is moving outwards a speed of about 50 000 km/hour and, by combining this speed with the distance between layers, astronomers calculate that the shells are each separated by about 800 years.
The spiral is thought to arise because LL Pegasi is a binary system, with the star that is losing material and a companion star orbiting each other. The spacing between layers in the spiral is expected to directly reflect the orbital period of the binary, which is indeed estimated to be also about 800 years.
The creation and shaping of planetary nebulae is an exciting area of stellar evolution. Stars with masses from about half that of the Sun up to about eight times that of the Sun do not explode as supernovae at the ends of their lives. Instead a more regal end awaits them as their outer layers of gas are shed and drift into space, creating striking and intricate structures that to Earth-bound observers often look like dramatic watercolour paintings. IRAS 23166+1655 is just starting this process and the central star has yet to emerge from the cocoon of enveloping dust.
This picture was created from images from the Wide Field Channel of the Advanced Camera for Surveys on Hubble. Images through a yellow filter (F606W, coloured blue) were combined with images through a near-infra red filter (F804W, coloured red). The exposure times were 11 minutes and 22 minutes respectively and the field of view spans about 80 arcseconds.
The image shows a pair of colossal stars, WR 25 and Tr16-244, located within the open cluster Trumpler 16. This cluster is embedded within the Carina Nebula, an immense cauldron of gas and dust that lies approximately 7500 light-years from Earth in the constellation of Carina, the Keel. WR 25 is the brightest, situated near the centre of the image. The neighbouring Tr16-244 is the third brightest, just to the upper left of WR 25. The second brightest, to the left of WR 25, is a low mass star located much closer to the Earth than the Carina Nebula.
Credit:
NASA, ESA and Jesús Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain)
This is an image of MyCn18, a young planetary nebula located about 8,000 light-years away, taken with the Wide Field and Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope (HST).
This Hubble image reveals the true shape of MyCn18 to be an hourglass with an intricate pattern of ‘etchings’ in its walls. This picture has been composed from three separate images taken in the light of ionized nitrogen (represented by red), hydrogen (green), and doubly-ionized oxygen (blue).
The results are of great interest because they shed new light on the poorly understood ejection of stellar matter which accompanies the slow death of Sun-like stars. In previous ground-based images, MyCn18 appears to be a pair of large outer rings with a smaller central one, but the fine details cannot be seen.
Credit:
Raghvendra Sahai and John Trauger (JPL), the WFPC2 science team, andNASA/ESA
This captivating new image shows the Crab Nebula in bright neon colours. The unusual image was produced by combining data from telescopes spanning nearly the entire electromagnetic spectrum, from radio waves to X-rays. The Karl G. Jansky Very Large Array (VLA) provided information about the nebula gathered in the radio regime (coloured in red). NASA’s Spitzer Space Telescope took images in the infrared (yellow). The NASA/ESA Hubble Space Telescope provided the images made in optical wavelengths (coloured in green). ESA’s XMM-Newton telescope observed the Crab Nebula in the ultraviolet (blue) and NASA’s Chandra X-ray Observatory provided the data for X-ray radiation (purple).
The Crab Nebula, located 6500 light-years from Earth in the constellation of Taurus (The Bull), is the result of a supernova explosion which was observed by Chinese and other astronomers in 1054. At its centre is a pulsar: a super-dense neutron star, spinning once every 33 milliseconds, shooting out rotating lighthouse-like beams of radio waves and visible light.
Surrounding the pulsar lies a mix of material; some of it was originally expelled from the star before it went supernova, and the rest was ejected during the explosion itself. Fast-moving winds of particles fly off from the neutron star, energising the dust and gas around it. These different layers and intricacies of the nebula can be observed in all of the different wavelengths of light.
NASA, ESA, G. Dubner (IAFE, CONICET-University of Buenos Aires) et al.; A. Loll et al.; T. Temim et al.; F. Seward et al.; VLA/NRAO/AUI/NSF; Chandra/CXC; Spitzer/JPL-Caltech; XMM-Newton/ESA; and Hubble/STScI
30 Doradus is the brightest star-forming region in our galactic neighbourhood and home to the most massive stars ever seen. The nebula resides 170 000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region in our galaxy is as large or as prolific as 30 Doradus.
The image comprises one of the largest mosaics ever assembled from Hubble photos and includes observations taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys, combined with observations from the European Southern Observatory’s MPG/ESO 2.2-metre telescope which trace the location of glowing hydrogen and oxygen.
The image is being released to celebrate Hubble’s 22nd anniversary.
Credit:
NASA, ESA, ESO, D. Lennon and E. Sabbi (ESA/STScI), J. Anderson, S. E. de Mink, R. van der Marel, T. Sohn, and N. Walborn (STScI), N. Bastian (Excellence Cluster, Munich), L. Bedin (INAF, Padua), E. Bressert (ESO), P. Crowther (Sheffield), A. de Koter (Amsterdam), C. Evans (UKATC/STFC, Edinburgh), A. Herrero (IAC, Tenerife), N. Langer (AifA, Bonn), I. Platais (JHU) and H. Sana (Amsterdam)
Hubble view of the huge star formation region N11 in the Large Magellanic Cloud
This broad vista of young stars and gas clouds in our neighbouring galaxy, the Large Magellanic Cloud, was captured by the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS). This region is named LHA 120-N 11, informally known as N11, and is one of the most active star formation regions in the nearby Universe. This picture is a mosaic of ACS data from five different positions and covers a region about six arcminutes across.
Credit:
NASA, ESA and Jesús Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain)
The star cluster Pismis 24 lies in the core of the large emission nebula NGC 6357 that extends one degree on the sky in the direction of the Scorpius constellation. Part of the nebula is ionised by the youngest (bluest) heavy stars in Pismis 24. The intense ultraviolet radiation from the blazing stars heats the gas surrounding the cluster and creates a bubble in NGC 6357. The presence of these surrounding gas clouds makes probing into the region even harder.
One of the top candidates for the title of “Milky Way stellar heavyweight champion” was, until now, Pismis 24-1, a bright young star that lies in the core of the small open star cluster Pismis 24 (the bright stars in the Hubble image) about 8,000 light-years away from Earth. Pismis 24-1 was thought to have an incredibly large mass of 200 to 300 solar masses. New NASA/ESA Hubble measurements of the star, have, however, resolved Pismis 24-1 into two separate stars, and, in doing so, have “halved” its mass to around 100 solar masses.
Cassiopeia A – The colourful aftermath of a violent stellar death
A new image taken with the NASA/ESA Hubble Space Telescope provides a detailed look at the tattered remains of a supernova explosion known as Cassiopeia A (Cas A). It is the youngest known remnant from a supernova explosion in the Milky Way. The new Hubble image shows the complex and intricate structure of the star’s shattered fragments.
Credit:
NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration. Acknowledgement: Robert A. Fesen (Dartmouth College, USA) and James Long (ESA/Hubble)
The yearly ritual of spring cleaning clears a house of dust as well as dust “bunnies”, those pesky dust balls that frolic under beds and behind furniture. NASA/ESA Hubble Space Telescope has photographed similar dense knots of dust and gas in our Milky Way Galaxy. This cosmic dust, however, is not a nuisance. It is a concentration of elements that are responsible for the formation of stars in our galaxy and throughout the universe.
These opaque, dark knots of gas and dust are called Bok globules, and they are absorbing light in the center of the nearby emission nebula and star-forming region, NGC 281. The globules are named after astronomer Bart Bok, who proposed their existence in the 1940’s.
Credit:
NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
Acknowledgment: P. McCullough (STScI)
Nebula NGC 2080, nicknamed the ‘Ghost Head Nebula’
The ‘Ghost Head Nebula’ is one of a chain of star-forming regions lying south of the 30 Doradus nebula in the Large Magellanic Cloud. Two bright regions (the ‘eyes of the ghost’), named A1 (left) and A2 (right), are very hot, glowing ‘blobs’ of hydrogen and oxygen. The bubble in A1 is produced by the hot, intense radiation and powerful stellar wind from a single massive star. A2 has a more complex appearance due to the presence of more dust, and it contains several hidden, massive stars. The massive stars in A1 and A2 must have formed within the last 10 000 years since their natal gas shrouds are not yet disrupted by the powerful radiation of the newly born stars.
Credit:
ESA, NASA, & Mohammad Heydari-Malayeri (Observatoire de Paris, France)
This glowing nebula, named NGC 248, is located within the Small Magellanic Cloud, a satellite galaxy of the Milky Way and about 200 000 light-years from Earth. The nebula was observed with Hubble’s Advanced Camera for Surveys in September 2015, as part of a survey called the Small Magellanic cloud Investigation of Dust and Gas Evolution (SMIDGE).
Credit:
NASA, ESA, STScI, K. Sandstrom (University of California, San Diego), and the SMIDGE team.
This new NASA/ESA Hubble Space Telescope image shows the Lagoon Nebula, an object with a deceptively tranquil name. The region is filled with intense winds from hot stars, churning funnels of gas, and energetic star formation, all embedded within an intricate haze of gas and pitch-dark dust.
This new NASA/ESA Hubble Space Telescope image shows a variety of intriguing cosmic phenomena.
Surrounded by bright stars, towards the upper middle of the frame we see a small young stellar object (YSO) known as SSTC2D J033038.2+303212. Located in the constellation of Perseus, this star is in the early stages of its life and is still forming into a fully grown star. In this view from Hubble’s Advanced Camera for Surveys (ACS) it appears to have a murky chimney of material emanating outwards and downwards, framed by bright bursts of gas flowing from the star itself. This fledgling star is actually surrounded by a bright disc of material swirling around it as it forms — a disc that we see edge-on from our perspective.
However, this small bright speck is dwarfed by its cosmic neighbour towards the bottom of the frame, a clump of bright, wispy gas swirling around as it appears to spew dark material out into space. The bright cloud is a reflection nebula known as [B77] 63, a cloud of interstellar gas that is reflecting light from the stars embedded within it. There are actually a number of bright stars within [B77] 63, most notably the emission-line star LkHA 326, and its very near neighbour LZK 18.
These stars are lighting up the surrounding gas and sculpting it into the wispy shape seen in this image. However, the most dramatic part of the image seems to be a dark stream of smoke piling outwards from [B77] 63 and its stars — a dark nebula called Dobashi 4173. Dark nebulae are incredibly dense clouds of pitch-dark material that obscure the patches of sky behind them, seemingly creating great rips and eerily empty chunks of sky. The stars speckled on top of this extreme blackness actually lie between us and Dobashi 4173.
The NASA/ESA Hubble Space Telescope celebrates the holiday season with a striking image of the planetary nebula NGC 5189. The intricate structure of the stellar eruption looks like a giant and brightly coloured ribbon in space.
Credit:
NASA, ESA and the Hubble Heritage Team (STScI/AURA)
The Hubble telescope reveals a rainbow of colours in this dying star, called IC 4406. Like many other so-called planetary nebulae, IC 4406 exhibits a high degree of symmetry. The nebula’s left and right halves are nearly mirror images of the other. If we could fly around IC 4406 in a spaceship, we would see that the gas and dust form a vast donut of material streaming outward from the dying star. We don’t see the donut shape in this photograph because we are viewing IC 4406 from the Earth-orbiting Hubble telescope. From this vantage point, we are seeing the side of the donut.
This side view allows us to see the intricate tendrils of material that have been compared to the eye’s retina. In fact, IC 4406 is dubbed the ‘Retina Nebula.’
NGC 2346 is a so-called “planetary nebula,” which is ejected from Sun-like stars which are near the ends of their lives. NGC 2346 is remarkable because its central star is known to be actually a very close pair of stars, orbiting each other every 16 days. It is believed that the binary star was originally more widely separated. However, when one component of the binary evolved, expanded in size, and became a red-giant star, it literally swallowed its companion star. The companion star then spiralled downwards inside the red giant, and in the process spewed out gas into aring around the binary system. Later on, when the hot core of the red giant was exposed, it developed a faster stellar wind, which emerged perpendicularly to the ring and inflated two huge “bubbles”. This two-stage process is believed to have resulted in the butterfly-like shape of the nebula. NGC 2346 lies about 2,000 light-years away from us, and is about one-third of a light-year in size.
A colourful star-forming region is featured in this stunning new NASA/ESA Hubble Space Telescope image of NGC 2467. Looking like a roiling cauldron of some exotic cosmic brew, huge clouds of gas and dust are sprinkled with bright blue, hot young stars.
Strangely shaped dust clouds, resembling spilled liquids, are silhouetted against a colourful background of glowing. Like the familiar Orion Nebula, NGC 2467 is a huge cloud of gas — mostly hydrogen — that serves as an incubator for new stars.
This picture was created from images taken with the Wide Field Channel of the Advanced Camera for Surveys through three different filters (F550M, F660N and F658N, shown in blue, green and red). These filters were selected to let through different colours of red and yellow light arising from different elements in the gas. The total aggregate exposure time was about 2000 seconds and the field of view is about 3.5 arcminutes across. These data were taken in 2004.
Credit:
NASA, ESA and Orsola De Marco (Macquarie University)
The Tarantula is situated 170,000 light-years away in the Large Magellanic Cloud (LMC) in the Southern sky and is clearly visible to the naked eye as a large milky patch. Astronomers believe that this smallish irregular galaxy is currently going through a violent period in its life. It is orbiting around the Milky Way and has had several close encounters with it. It is believed that the interaction with the Milky Way has caused an episode of energetic star formation – part of which is visible as the Tarantula Nebula.
Just above the centre of the image there is a huge cluster of very hot stars called R136. The stars in R136 are also among the most massive stars we know. R136 is also a very young cluster, its oldest stars being “just” 5 million years old or so. Its smallest stars, however, are still forming, so astronomers observe R136 to try to understand the early stages of stellar evolution. Near the lower edge of the image we find the star cluster Hodge 301. Hodge 301 is almost 10 times older than R136. Some of the stars in Hodge 301 are so old that they have already exploded as supernovae. The shockwave from this explosion has compressed the gas in the Tarantula into the filaments and sheets that are seen around the cluster.
This mosaic of the Tarantula Nebula consists of images from the NASA/ESA Hubble Space Telescope’s Wide Field and Planetary Camera 2 (WFPC2) and was created by 23 year old amateur astronomer Danny LaCrue. The image was constructed by 15 individual exposures taken through three narrow-band filters allowing light from ionised oxygen (501 nm, shown as blue), hydrogen-alpha (656 nm, shown as green) and ionised sulphur (672 nm, shown as red). The exposure time for the individual WFPC2 images vary between 800 and 2800 seconds in each filter. The Hubble data have been superimposed onto images taken through matching narrow-band filters with the European Southern Observatory’s New Technology Telescope at the La Silla Observatory, Chile. Additional image processing was done by the Hubble European Space Agency Information Centre.
Dying star creates fantasy-like sculpture of gas and dust
In this detailed view from the NASA/ESA Hubble Space Telescope, the so-called Cat’s Eye Nebula looks like the penetrating eye of the disembodied sorcerer Sauron from the film adaptation of “Lord of the Rings.”
The nebula, formally catalogued NGC 6543, is every bit as inscrutable as the J.R.R. Tolkien phantom character. Although the Cat’s Eye Nebula was among the first planetary nebula ever to be discovered, it is one of the most complex planetary nebulae ever seen in space. A planetary nebula forms when Sun-like stars gently eject their outer gaseous layers to form bright nebulae with amazing twisted shapes.
Eleven years in orbit: Hubble observes the popular Horsehead nebula
Rising from a sea of dust and gas like a giant sea horse, the Horsehead Nebula, located in the constellation of Orion, is a cold, dark cloud of gas and dust. The bright area at the top left-hand edge is a young star still embedded in its nursery of gas and dust. Radiation from this hot star is eroding its gaseous birthplace. A massive star located outside Hubble’s view is sculpting the top of the Horsehead itself in a similar way.
Rising from a sea of dust and gas like a giant seahorse, the Horsehead nebula is one of the most photographed objects in the sky. NASA/ESA Hubble Space Telescope took a close-up look at this heavenly icon, revealing the cloud’s intricate structure. This detailed view of the horse’s head is being released to celebrate the orbiting observatory’s eleventh anniversary. Produced by the Hubble Heritage Project, this picture is a testament to the Horsehead’s popularity. Internet voters selected this object for the orbiting telescope to view.
The Horsehead, also known as Barnard 33, is a cold, dark cloud of gas and dust, silhouetted against the bright nebula, IC 434. The bright area at the top left edge is a young star still embedded in its nursery of gas and dust. But radiation from this hot star is eroding the stellar nursery. The top of the nebula also is being sculpted by radiation from a massive star located out of Hubble’s field of view.
In its first glimpse of the heavens following the successful December 1999 servicing mission, the NASA/ESA Hubble Space Telescope has captured a majestic view of a planetary nebula, the glowing remains of a dying, Sun-like star.
This NASA/ESA Hubble Space Telescope image of the cluster Westerlund 2 and its surroundings has been released to celebrate Hubble’s 25th year in orbit and a quarter of a century of new discoveries, stunning images and outstanding science.
The image’s central region, containing the star cluster, blends visible-light data taken by the Advanced Camera for Surveys and near-infrared exposures taken by the Wide Field Camera 3. The surrounding region is composed of visible-light observations taken by the Advanced Camera for Surveys.
Credit:
NASA, ESA, the Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), and the Westerlund 2 Science Team
The original observations of Westerlund 2 were obtained by the science team: Antonella Nota (ESA/STScI), Elena Sabbi (STScI), Eva Grebel and Peter Zeidler (Astronomisches Rechen-Institut Heidelberg), Monica Tosi (INAF, Osservatorio Astronomico di Bologna), Alceste Bonanos (National Observatory of Athens, Astronomical Institute), Carol Christian (STScI/AURA) and Selma de Mink (University of Amsterdam). Follow-up observations were made by the Hubble Heritage team: Zoltan Levay (STScI), Max Mutchler, Jennifer Mack, Lisa Frattare, Shelly Meyett, Mario Livio, Carol Christian (STScI/AURA), and Keith Noll (NASA/GSFC).
The NASA/ESA Hubble Space Telescope has revisited one of its most iconic and popular images: the Eagle Nebula’s Pillars of Creation. This image shows the pillars as seen in visible light, capturing the multi-coloured glow of gas clouds, wispy tendrils of dark cosmic dust, and the rust-coloured elephants’ trunks of the nebula’s famous pillars.
The dust and gas in the pillars is seared by the intense radiation from young stars and eroded by strong winds from massive nearby stars. With these new images comes better contrast and a clearer view for astronomers to study how the structure of the pillars is changing over time.
The star-forming region NGC 3603 – seen here in the latest Hubble Space Telescope image – contains one of the most impressive massive young star clusters in the Milky Way. Bathed in gas and dust the cluster formed in a huge rush of star formation thought to have occurred around a million years ago. The hot blue stars at the core are responsible for carving out a huge cavity in the gas seen to the right of the star cluster in NGC 3603’s centre.
Credit:
NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
The Bubble Nebula, also known as NGC 7635, is an emission nebula located 8 000 light-years away. This stunning new image was observed by the NASA/ESA Hubble Space Telescope to celebrate its 26th year in space.
Credit:
NASA, ESA, Hubble Heritage Team
New infrared view of the Horsehead Nebula — Hubble’s 23rd anniversary image
This new Hubble image, captured and released to celebrate the telescope’s 23rd year in orbit, shows part of the sky in the constellation of Orion (The Hunter). Rising like a giant seahorse from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33.
This image shows the region in infrared light, which has longer wavelengths than visible light and can pierce through the dusty material that usually obscures the nebula’s inner regions. The result is a rather ethereal and fragile-looking structure, made of delicate folds of gas — very different to the nebula’s appearance in visible light.
Credit:
NASA, ESA, and the Hubble Heritage Team (AURA/STScI)
Coordinates
Position (RA):
5 41 0.99
Position (Dec):
-2° 27′ 11.92″
Field of view:
5.78 x 6.04 arcminutes
Orientation:
North is 103.0° left of vertical
New stars shed light on the past
This image depicts bright blue newly formed stars that are blowing a cavity in the centre of a fascinating star-forming region known as N90.
The high energy radiation blazing out from the hot young stars in N90 is eroding the outer portions of the nebula from the inside, as the diffuse outer reaches of the nebula prevent the energetic outflows from streaming away from the cluster directly. Because N90 is located far from the central body of the Small Magellanic Cloud, numerous background galaxies in this picture can be seen, delivering a grand backdrop for the stellar newcomers. The dust in the region gives these distant galaxies a reddish-brown tint.
This Hubble image gives the most detailed view of the entire Crab Nebula ever. The Crab is among the most interesting and well studied objects in astronomy.
This image is the largest image ever taken with Hubble’s WFPC2 camera. It was assembled from 24 individual exposures taken with the NASA/ESA Hubble Space Telescope and is the highest resolution image of the entire Crab Nebula ever made.
Credit:
NASA, ESA and Allison Loll/Jeff Hester (Arizona State University). Acknowledgement: Davide De Martin (ESA/Hubble)
To celebrate its 28th anniversary in space the NASA/ESA Hubble Space Telescope took this amazing and colourful image of the Lagoon Nebula. The whole nebula, about 4000 light-years away, is an incredible 55 light-years wide and 20 light-years tall. This image shows only a small part of this turbulent star-formation region, about four light-years across.
This stunning nebula was first catalogued in 1654 by the Italian astronomer Giovanni Battista Hodierna, who sought to record nebulous objects in the night sky so they would not be mistaken for comets. Since Hodierna’s observations, the Lagoon Nebula has been photographed and analysed by many telescopes and astronomers all over the world.
The observations were taken by Hubble’s Wide Field Camera 3 between 12 February and 18 February 2018.
Butterfly emerges from stellar demise in planetary nebula NGC 6302
This celestial object looks like a delicate butterfly. But it is far from serene.
What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to nearly 20 000 degrees Celsius. The gas is tearing across space at more than 950 000 kilometres per hour — fast enough to travel from Earth to the Moon in 24 minutes!
A dying star that was once about five times the mass of the Sun is at the centre of this fury. It has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula, so-named because many of them have a round appearance resembling that of a planet when viewed through a small telescope.
The Wide Field Camera 3 (WFC3), a new camera aboard the NASA/ESA Hubble Space Telescope, snapped this image of the planetary nebula, catalogued as NGC 6302, but more popularly called the Bug Nebula or the Butterfly Nebula. WFC3 was installed by NASA astronauts in May 2009, during the Servicing Mission to upgrade and repair the 19-year-old Hubble.
NGC 6302 lies within our Milky Way galaxy, roughly 3800 light-years away in the constellation of Scorpius. The glowing gas is the star’s outer layers, expelled over about 2200 years. The “butterfly” stretches for more than two light-years, which is about half the distance from the Sun to the nearest star, Proxima Centauri.
The central star itself cannot be seen, because it is hidden within a doughnut-shaped ring of dust, which appears as a dark band pinching the nebula in the centre. The thick dust belt constricts the star’s outflow, creating the classic “bipolar” or hourglass shape displayed by some planetary nebulae.
The star’s surface temperature is estimated to be over 220 000 degrees Celsius, making it one of the hottest known stars in our galaxy. Spectroscopic observations made with ground-based telescopes show that the gas is roughly 20 000 degrees Celsius, which is unusually hot compared to a typical planetary nebula.
The WFC3 image reveals a complex history of ejections from the star. The star first evolved into a huge red giant, with a diameter of about 1000 times that of our Sun. It then lost its extended outer layers. Some of this gas was cast off from its equator at a relatively slow speed, perhaps as low as 32 000 kilometres per hour, creating the doughnut-shaped ring. Other gas was ejected perpendicular to the ring at higher speeds, producing the elongated “wings” of the butterfly-shaped structure. Later, as the central star heated up, a much faster stellar wind, a stream of charged particles travelling at more than 3.2 million kilometres per hour, ploughed through the existing wing-shaped structure, further modifying its shape.
The image also shows numerous finger-like projections pointing back to the star, which may mark denser blobs in the outflow that have resisted the pressure from the stellar wind.
The nebula’s reddish outer edges are largely due to light emitted by nitrogen, which marks the coolest gas visible in the picture. WFC3 is equipped with a wide variety of filters that isolate light emitted by various chemical elements, allowing astronomers to infer properties of the nebular gas, such as its temperature, density and composition.
The white-coloured regions are areas where light is emitted by sulphur. These are regions where fast-moving gas overtakes and collides with slow-moving gas that left the star at an earlier time, producing shock waves in the gas (the bright white edges on the sides facing the central star). The white blob with the crisp edge at upper right is an example of one of those shock waves.
NGC 6302 was imaged on 27 July 2009 with Hubble’s Wide Field Camera 3 in ultraviolet and visible light. Filters that isolate emissions from oxygen, helium, hydrogen, nitrogen and sulphur from the planetary nebula were used to create this composite image.
These Hubble observations of the planetary nebula NGC 6302 are part of the Hubble Servicing Mission 4 Early Release Observations.
This dramatic image offers a peek inside a cavern of roiling dust and gas where thousands of stars are forming. The image, taken by the Advanced Camera for Surveys (ACS) aboard NASA/ESA Hubble Space Telescope, represents the sharpest view ever taken of this region, called the Orion Nebula. More than 3,000 stars of various sizes appear in this image. Some of them have never been seen in visible light. These stars reside in a dramatic dust-and-gas landscape of plateaus, mountains, and valleys that are reminiscent of the Grand Canyon.
The Orion Nebula is a picture book of star formation, from the massive, young stars that are shaping the nebula to the pillars of dense gas that may be the homes of budding stars. The bright central region is the home of the four heftiest stars in the nebula. The stars are called the Trapezium because they are arranged in a trapezoid pattern. Ultraviolet light unleashed by these stars is carving a cavity in the nebula and disrupting the growth of hundreds of smaller stars. Located near the Trapezium stars are stars still young enough to have disks of material encircling them. These disks are called protoplanetary disks or “proplyds” and are too small to see clearly in this image. The disks are the building blocks of solar systems.
The bright glow at upper left is from M43, a small region being shaped by a massive, young star’s ultraviolet light. Astronomers call the region a miniature Orion Nebula because only one star is sculpting the landscape. The Orion Nebula has four such stars. Next to M43 are dense, dark pillars of dust and gas that point toward the Trapezium. These pillars are resisting erosion from the Trapezium’s intense ultraviolet light. The glowing region on the right reveals arcs and bubbles formed when stellar winds – streams of charged particles ejected from the Trapezium stars – collide with material.
The faint red stars near the bottom are the myriad brown dwarfs that Hubble spied for the first time in the nebula in visible light. Sometimes called “failed stars,” brown dwarfs are cool objects that are too small to be ordinary stars because they cannot sustain nuclear fusion in their cores the way our Sun does. The dark red column, below, left, shows an illuminated edge of the cavity wall.
The Orion Nebula is 1,500 light-years away, the nearest star-forming region to Earth. Astronomers used 520 Hubble images, taken in five colours, to make this picture. They also added ground-based photos to fill out the nebula. The ACS mosaic covers approximately the apparent angular size of the full moon.
The Orion observations were taken between 2004 and 2005.
This Hubble Space Telescope view shows one of the most dynamic and intricately detailed star-forming regions in space, located 210,000 light-years away in the Small Magellanic Cloud (SMC), a satellite galaxy of our Milky Way. At the centre of the region is a brilliant star cluster called NGC 346. A dramatic structure of arched, ragged filaments with a distinct ridge surrounds the cluster.
A torrent of radiation from the hot stars in the cluster NGC 346, at the centre of this Hubble image, eats into denser areas around it, creating a fantasy sculpture of dust and gas. The dark, intricately beaded edge of the ridge, seen in silhouette, is particularly dramatic. It contains several small dust globules that point back towards the central cluster, like windsocks caught in a gale.
The Eagle has risen: stellar spire in the Eagle Nebula
Appearing like a winged fairy-tale creature poised on a pedestal, this object is actually a billowing tower of cold gas and dust rising from a stellar nursery called the Eagle Nebula. The soaring tower is 9.5 light-years or about 90 trillion kilometres high, about twice the distance from our Sun to the next nearest star.
Stars in the Eagle Nebula are born in clouds of cold hydrogen gas that reside in chaotic neighbourhoods, where energy from young stars sculpts fantasy-like landscapes in the gas. The tower may be a giant incubator for those newborn stars. A torrent of ultraviolet light from a band of massive, hot, young stars [off the top of the image] is eroding the pillar.
The starlight also is responsible for illuminating the tower’s rough surface. Ghostly streamers of gas can be seen boiling off this surface, creating the haze around the structure and highlighting its three-dimensional shape. The column is silhouetted against the background glow of more distant gas.
The edge of the dark hydrogen cloud at the top of the tower is resisting erosion, in a manner similar to that of brush among a field of prairie grass that is being swept up by fire. The fire quickly burns the grass but slows down when it encounters the dense brush. In this celestial case, thick clouds of hydrogen gas and dust have survived longer than their surroundings in the face of a blast of ultraviolet light from the hot, young stars.
Inside the gaseous tower, stars may be forming. Some of those stars may have been created by dense gas collapsing under gravity. Other stars may be forming due to pressure from gas that has been heated by the neighbouring hot stars.
The first wave of stars may have started forming before the massive star cluster began venting its scorching light. The star birth may have begun when denser regions of cold gas within the tower started collapsing under their own weight to make stars.
The bumps and fingers of material in the centre of the tower are examples of these stellar birthing areas. These regions may look small but they are roughly the size of our solar system. The fledgling stars continued to grow as they fed off the surrounding gas cloud. They abruptly stopped growing when light from the star cluster uncovered their gaseous cradles, separating them from their gas supply.
Ironically, the young cluster’s intense starlight may be inducing star formation in some regions of the tower. Examples can be seen in the large, glowing clumps and finger-shaped protrusions at the top of the structure. The stars may be heating the gas at the top of the tower and creating a shock front, as seen by the bright rim of material tracing the edge of the nebula at top, left. As the heated gas expands, it acts like a battering ram, pushing against the darker cold gas. The intense pressure compresses the gas, making it easier for stars to form. This scenario may continue as the shock front moves slowly down the tower.
The dominant colours in the image were produced by gas energized by the star cluster’s powerful ultraviolet light. The blue colour at the top is from glowing oxygen. The red colon in the lower region is from glowing hydrogen. The Eagle Nebula image was taken in November 2004 with the Advanced Camera for Surveys aboard the NASA/ESA Hubble Space Telescope.
Light continues to echo three years after stellar outburst
The Hubble Space Telescope’s latest image of the star V838 Monocerotis (V838 Mon) reveals dramatic changes in the illumination of surrounding dusty cloud structures. The effect, called a light echo, has been unveiling never-before-seen dust patterns ever since the star suddenly brightened for several weeks in early 2002.
Hubble’s newest camera images ghostly star-forming pillar of gas and dust
Resembling a nightmarish beast rearing its head from a crimson sea, this celestial object is actually just a pillar of gas and dust. Called the Cone Nebula (in NGC 2264) – so named because in ground-based images it has a conical shape – this monstrous pillar resides in a turbulent star-forming region. This picture, taken by the newly installed Advanced Camera for Surveys (ACS) aboard the NASA/ESA Hubble Space Telescope, shows the upper 2.5 light-years of the Cone, a height that equals 23 million roundtrips to the Moon. The entire pillar is seven light-years long.
Radiation from hot, young stars (located beyond the top of the image) has slowly eroded the nebula over millions of years. Ultraviolet light heats the edges of the dark cloud, releasing gas into the relatively empty region of surrounding space. There, additional ultraviolet radiation causes the hydrogen gas to glow, which produces the red halo of light seen around the pillar. A similar process occurs on a much smaller scale to gas surrounding a single star, forming the bow-shaped arc seen near the upper left side of the Cone. This arc, seen previously with the Hubble telescope, is 65 times larger than the diameter of our Solar System. The blue-white light from surrounding stars is reflected by dust. Background stars can be seen peeking through the evaporating tendrils of gas, while the turbulent base is pockmarked with stars reddened by dust.
Over time, only the densest regions of the Cone will be left. But inside these regions, stars and planets may form. The Cone Nebula resides 2500 light-years away in the constellation Monoceros.
The Cone is a cousin of the M16 pillars, which the Hubble telescope imaged in 1995. Consisting mainly of cold gas, the pillars in both regions resist being eroded away by the blistering ultraviolet radiation from young, massive stars. Pillars like the Cone and M16 are common in large regions of star birth. Astronomers believe that these pillars may be incubators for developing stars.
The ACS made this observation on 2 April 2002. The colour image is constructed from three separate images taken in blue, near-infrared, and hydrogen-alpha filters.
Image credit: NASA, the ACS Science Team (H. Ford, G. Illingworth, M. Clampin, G. Hartig, T. Allen, K. Anderson, F. Bartko, N. Benitez, J. Blakeslee, R. Bouwens, T. Broadhurst, R. Brown, C. Burrows, D. Campbell, E. Cheng, N. Cross, P. Feldman, M. Franx, D. Golimowski, C. Gronwall, R. Kimble, J. Krist, M. Lesser, D. Magee, A. Martel, W. J. McCann, G. Meurer, G. Miley, M. Postman, P. Rosati, M. Sirianni, W. Sparks, P. Sullivan, H. Tran, Z. Tsvetanov, R. White, and R. Woodruff) and ESA
Credit:
NASA, Holland Ford (JHU), the ACS Science Team and ESA
The Red Spider Nebula: surfing in Sagittarius – not for the faint-hearted!
Huge waves are sculpted in this two-lobed nebula some 3000 light-years away in the constellation of Sagittarius. This warm planetary nebula harbours one of the hottest stars known and its powerful stellar winds generate waves 100 billion kilometres high. The waves are caused by supersonic shocks, formed when the local gas is compressed and heated in front of the rapidly expanding lobes. The atoms caught in the shock emit the spectacular radiation seen in this image.
Credit:
ESA & Garrelt Mellema (Leiden University, the Netherlands)
Previously unseen details of a mysterious, complex structure within the Carina Nebula (NGC 3372) are revealed by this image of the ‘Keyhole Nebula, ‘ obtained with the Hubble Space Telescope. The picture is a montage assembled from four different April 1999 telescope pointings with Hubble’s Wide Field Planetary Camera 2, which used six different colour filters. The picture is dominated by a large, approximately circular feature, which is part of the Keyhole Nebula, named in the 19th century by Sir John Herschel. This region, about 8000 light-years from Earth, is located adjacent to the famous explosive variable star Eta Carinae, which lies just outside the field of view toward the upper right. The Carina Nebula also contains several other stars that are among the hottest and most massive known, each about 10 times as hot, and 100 times as massive, as our Sun.
Hubble has taken this stunning close-up shot of part of the Tarantula Nebula. This star-forming region of ionised hydrogen gas is in the Large Magellanic Cloud, a small galaxy which neighbours the Milky Way. It is home to many extreme conditions including supernova remnants and the heaviest star ever found. The Tarantula Nebula is the most luminous nebula of its type in the local Universe.
This craggy fantasy mountaintop enshrouded by wispy clouds looks like a bizarre landscape from Tolkien’s The Lord of the Rings. The NASA/ESA Hubble Space Telescope image, which is even more dramatic than fiction, captures the chaotic activity atop a pillar of gas and dust, three light-years tall, which is being eaten away by the brilliant light from nearby bright stars. The pillar is also being assaulted from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks.
This turbulent cosmic pinnacle lies within a tempestuous stellar nursery called the Carina Nebula, located 7500 light-years away in the southern constellation of Carina. The image celebrates the 20th anniversary of Hubble’s launch and deployment into an orbit around the Earth.
Scorching radiation and fast winds (streams of charged particles) from super-hot newborn stars in the nebula are shaping and compressing the pillar, causing new stars to form within it. Streamers of hot ionised gas can be seen flowing off the ridges of the structure, and wispy veils of gas and dust, illuminated by starlight, float around its towering peaks. The denser parts of the pillar are resisting being eroded by radiation.
Nestled inside this dense mountain are fledgling stars. Long streamers of gas can be seen shooting in opposite directions from the pedestal at the top of the image. Another pair of jets is visible at another peak near the centre of the image. These jets, (known as HH 901 and HH 902, respectively, are signposts for new star birth and are launched by swirling gas and dust discs around the young stars, which allow material to slowly accrete onto the stellar surfaces.
Hubble’s Wide Field Camera 3 observed the pillar on 1-2 February 2010. The colours in this composite image correspond to the glow of oxygen (blue), hydrogen and nitrogen (green), and sulphur (red).
Credit:
NASA, ESA, M. Livio and the Hubble 20th Anniversary Team (STScI)
Hubble’s view of the Carina Nebula shows star birth in a new level of detail. The fantasy-like landscape of the nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars that inhabit this inferno. In the process, these stars are shredding the surrounding material that is the last vestige of the giant cloud from which the stars were born.
The immense nebula is an estimated 7,500 light-years away in the southern constellation Carina the Keel (of the old southern constellation Argo Navis, the ship of Jason and the Argonauts, from Greek mythology).
This image is a mosaic of the Carina Nebula assembled from 48 frames taken with Hubble Space Telescope’s Advanced Camera for Surveys. The Hubble images were taken in the light of ionized hydrogen. Colour information was added with data taken at the Cerro Tololo Inter-American Observatory in Chile. Red corresponds to sulfur, green to hydrogen, and blue to oxygen emission.
Credit:
NASA, ESA, N. Smith (University of California, Berkeley), and The Hubble Heritage Team (STScI/AURA)
This image shows a dark interstellar cloud ravaged by the passage of Merope, one of the brightest stars in the Pleiades star cluster. Just as a torch beam bounces off the wall of a cave, the star is reflecting light from the surface of pitch-black clouds of cold gas laced with dust. As the nebula approaches Merope, the strong starlight shining on the dust decelerates the dust particles. The nebula is drifting through the cluster at a relative speed of roughly 11 kilometres per second.
The Hubble Space Telescope has caught the eerie, wispy tendrils of a dark interstellar cloud being destroyed by the passage of one of the brightest stars in the Pleiades star cluster. Like a flashlight beam shining off the wall of a cave, the star is reflecting light off the surface of pitch black clouds of cold gas laced with dust. These are called reflection nebulae.
Credit:
NASA/ESA and The Hubble Heritage Team (STScI/AURA), George Herbig and Theodore Simon (University of Hawaii).
Glowing like a multi-faceted jewel, the planetary nebula IC 418 lies about 2000 light-years from Earth in the constellation Lepus. In this picture, the Hubble telescope reveals some remarkable textures weaving through the nebula. Their origin, however, is still uncertain.
Green and purple northern lights shimmy over the Aurora Ice Museum at Chena Hot Springs near Fairbanks, Alaska in this image by astrophotographer John Chumack. He took the photo on March 24 during a minor geomagnetic storm caused by a coronal hole on the sun, which sent a stream of solar particles toward Earth. Those particles interact with Earth’s atmosphere to create colorful auroras. [View more of the album]
Coronal Loops Rotate Into View
Credit: NASA/GSFC/Solar Dynamics Observatory
Coronal loops billow out of the sun’s surface in this view from NASA’s Solar Dynamic Observatory. This video shows the sun’s new active region rotating into view on March 27-28. The Solar Dynamics Observatory views the sun in extreme ultraviolet wavelengths of light, which are invisible to the human eye, to monitor the sun’s corona for solar flares. This active region shows magnetic field lines protruding from the sun’s surface, but it has yet to produce any flares or solar storms. [View more of the album]
Countless stars and galaxies scatter across the cosmic field in this deep-space image by astrophotographer Terry Hancock. The large spiral galaxy near the center of the image is Messier 81, also known as Bode’s Galaxy. Just below that is the Cigar Galaxy, Messier 82. Both are located around 12 million light-years away from Earth in the constellation Ursa Major. These galaxies are seen through the faint haze of the Integrated Flux Nebula, a vast screen of interstellar dust and gas illuminated by starlight from the Milky Way. [View more of the album]
Migrating Martian Sands of Lobo Vallis
Credit: NASA/JPL-Caltech/Univ. of Arizona
In this view from NASA’s Mars Reconnaissance Orbiter, bands of bright ripples and dark dunes stretch across the surface of Mars. Over time, winds have pushed these sandy streaks, which are composed of basaltic sand, from the top of the image toward the bottom. This region of the Red Planet is known as Lobo Vallis and was named after a river on the Ivory Coast. [View more of the album]
Jupiter’s Swirling Storms
Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill
Elaborate cloud patterns swirl on Jupiter’s northern hemisphere in this new view from NASA’s Juno spacecraft. Juno captured the image on April 1 during its twelfth close flyby of Jupiter, when it was 7,659 miles (12,326 kilometers) from the planet’s cloud tops. Citizen scientist Kevin Gill processed this color-enhanced view using data from the spacecraft’s JunoCam imager. [View more of the album]
Antarctic Salad
Credit: DLR
German scientists have just collected — and eaten — their first batch of lettuce, cucumbers and radishes from a new greenhouse on Antarctica. The greenhouse, called EDEN ISS, was installed in February about a quarter-mile (400 meters) from the Neumayer Station III facility. It is an experiment led by the German Aerospace Center (DLR) designed to test the best methods for cultivating crops for astronauts.research station. [German Scientists Harvest Their 1st Antarctic Salad, and It Looks Amazing]
A colorful deep-space photo reveals many features of the Orion Molecular Cloud Complex. In the top center of the image, three bright blue supergiant stars — Mintaka, Alnilam and Alnitak (from left to right) — form a stellar triplet also known as Orion’s Belt, located in the constellation Orion the Hunter. This image was captured from the Cumeada Observatory, headquarters of the Dark Sky Alqueva Reserve in Portugal. [Cosmic Bling! Colorful Nebulas Decorate Orion’s Belt in Stargazer Photo]
Wormholes, or hypothetical tunnels through space-time that allow faster-than-light travel, could potentially leave dark, telltale imprints in the sky that might be seen with telescopes, a new study suggests.
These slightly bent, oblong wormhole “shadows” could be distinguished from the more circular patches left by black holes and, if detected, could show that the cosmic shortcuts first proposed by Albert Einstein more than a century ago are, in fact, real, one researcher says.
Wormholes are cosmic shortcuts, tunnels burrowing through hyperspace. Hop in one end, and you could emerge on the other side of the universe — a convenient method of hyperfast travel that’s become a trope of science fiction. [8 Ways You Can See Einstein’s Theory of Relativity in Real Life]
These sci-fi staples arise from the equations of Einstein’s theory of general relativity. Like the space-time around black holes, wormholes are regions where the fabric of space-time is so warped, light no longer travels in a straight line. Photons — or light particles from nearby gas, dust or background stars — careen around the wormhole, generating a ring of light. But photons too close would fall through the wormhole and leave behind a dark, round void called a shadow.
Such a shadow would be similar to those cast by black holes — including the supermassive one at the center of the Milky Way galaxy — which astronomers are now trying to observe directly. Its shadow would appear tiny, so astronomers are linking radio dishes across the globe to form an Earth-sized telescope, called the Event Horizon Telescope. They’re now analyzing the first batch of data, which they collected last year.
In the new analysis, published in the preprint journal arXiv on March 30, Rajibul Shaikh, a physicist at the Tata Institute of Fundamental Research in Mumbai, India, found that a certain type of rotating wormhole would cast a larger and more distorted shadow than the one cast by a black hole. As a wormhole spun faster, its shadow would appear a little smooshed, while a black hole’s shadow would remain more disk-like.
“Through the observation of their shadows, it might be possible to distinguish between black holes and wormholes,” Shaikh told Live Science.
Researchers have calculated a rotating wormhole’s shadow before, but they overlooked the effect of the wormhole’s “throat,” which connects its two ends, Shaikh said. Using the new analysis, astronomers could, in principle, identify a wormhole shadow when they see one. And if they do, it would not only be evidence of something out of science fiction but also indirect evidence for some kind of exotic matter or a modified theory of gravity, he said.
According to general relativity, a wormhole needs exotic (and still theoretical) matter that behaves like antigravity to keep it open, or else it would collapse immediately. Otherwise, a stable wormhole might require us to rethink our understanding of gravity, Shaikh said.
But the new analysis, which has been submitted for peer review in the journal Physical Review D, refers only to a specific class of wormholes. “It has to be studied whether or to what extent the results carry over to broader classes of wormholes,” Shaikh said.
This type of wormhole also has a simpler, unrealistic symmetry, said John Friedman, a physicist at the University of Wisconsin-Milwaukee who was not involved in the study. Shaikh’s new analysis probably wouldn’t apply to a more realistic wormhole because exotic matter is so mysterious.
“It’s highly unlikely that macroscopic wormholes exist,” Friedman told Live Science. “If they do, the unknown nature of the matter supporting the wormhole makes it impossible to predict the shadow.”
Calculating the shadow requires knowing the geometry of the space-time fabric around it. This geometry depends on the properties of exotic matter. But because no one knows what this matter might be, the exact geometry — and thus the shadow — would remain a mystery, Friedman said.
How a Bizarre Nazi Military Machine Left a Lasting Mark on the Environment
By Megan Gannon, Live Science Contributor |
The Germans release a colossal smoke screen in an effort to hide their battleship Tirpitz, moored in Kaa Fjord, Norway, as it’s attacked by a Lancaster on Sept. 15, 1944.
Credit: No. 5 Group RAF/IWM via Getty Images
VIENNA —The Tirpitz was the Nazis’ most imposing warship and the largest battleship ever built by a European navy. It should have been an easy target for bombers, but this massive vessel could hide in plain sight.
Hitler’s navy used a toxic artificial fog to conceal the ship when it was stationed in a Norwegian fjord. And, according to new research, this ephemeral smoke left a lasting mark on some of the living witnesses ofWorld War II: the trees.
“The effects of one military engagement during World War II are still evident in the forests of Norway, 70 years later,” said Claudia Hartl, a tree-ring researcher at the Johannes Gutenberg University in Mainz, Germany. [Images: Missing Nazi Diary Resurfaces]
Hartl, who presented her findings here during the annual meeting of the European Geosciences Union, didn’t set out to study “war dendrochronology.” Rather, she was taking core samples from pine trees around Kåfjord, near the northern edge of Scandinavia, to reconstruct a record of yearly temperatures for the past 2,000 years. (The trees can live for dozens or hundreds of years, and even older stumps can be found preserved in frigid lakes.)
“Trees are limited by temperature there, so if you have a cold year, trees form a narrow ring, and if you have a warm year, then you have wide ring,” Hartl explained.
At a site near the fjord, Hartl and her colleagues found trees that didn’t produce rings in 1945. This “exceptional stress response” didn’t fit with the researchers’ climate reconstructions, so they had to look for another explanation. And they learned that the Tirpitz had been stationed at Kåfjord, and was finally sunk by Allied bombs, in 1944.
Nicknamed “The Lonely Queen of the North” by Norwegians and “The Beast” by Winston Churchill, the battleship had been moored at Kåfjord to threaten Allied ships bringing supplies to the Soviet Union. Part of the Nazis’ defense was to release chlorosulfuric acid into the air, which attracts moisture and can create a smoke screen. Hartl said there is not much in historical records about the environmental impact of the fake fog. The substance is known to be corrosive, and the group of soldiers responsible for producing this smoke had to wear special protection suits.
The researchers sampled pine trees from six sites near the fjord. Trees farther away from the Tirpitz’s mooring were less affected by the fog. But at the site closest to the location of the battleship, 60 percent of the trees didn’t produce a ring in 1945, and some of the trees didn’t grow for several years after the war. Hartl’s team thinks the trees lost their needles due to the fog, which harmed their ability to photosynthesize.
War dendrochronology could join other nascent fields like “bombturbation” (the study of how bombs alter landscapes) as scientists begin to investigate the environmental impact of war.
“What I think is very interesting is the human impact on ecosystems,” Hartl told Live Science. “If you have a drought event, the trees also show a growth decline, but you can also see that these trees recover, and usually, it doesn’t take longer than five years. But in northern Scandinavia, through this Second World War impact, it took the trees 12 years to recover. That’s a really strong impact.”
