This is the most violent object in the solar system

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This is the most violent object in the solar system

The Universe May Be Flooded with a Cobweb Network of Invisible Strings

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The Universe May Be Flooded with a Cobweb Network of Invisible Strings

By Paul Sutter – Astrophysicist January 02, 2020

We may soon find out whether we live in an axiverse.

an abstract image of axion strings

(Image: © Shutterstock)

What if I told you that our universe was flooded with hundreds of kinds of nearly invisible particles and that, long ago, these particles formed a network of universe-spanning strings?

It sounds both trippy and awesome, but it’s actually a prediction of string theory, our best (but frustratingly incomplete) attempt at a theory of everything. These bizarre, albeit hypothetical, little particles are known as axions, and if they can be found, that would mean we all live in a vast “axiverse.”

The best part of this theory is that it’s not just some physicist’s armchair hypothesis, with no possibility of testing. This incomprehensibly huge network of strings may be detectable in the near future with microwave telescopes that are actually being built.

Related: The Biggest Unsolved Mysteries in Physics

If found, the axiverse would give us a major step up in figuring out the puzzle of … well, all of physics.

A symphony of strings

OK, let’s get down to business. First, we need to get to know the axion a little better. The axion, named by physicist (and, later, Nobel laureate) Frank Wilczek in 1978, gets its name because it’s hypothesized to exist from a certain kind of symmetry-breaking. I know, I know — more jargon. Hold on. Physicists love symmetries — when certain patterns appear in mathematics.

There’s one kind of symmetry, called the CP symmetry, that says that matter and antimatter should behave the same when their coordinates are reversed. But this symmetry doesn’t seem to fit naturally into the theory of the strong nuclear force. One solution to this puzzle is to introduce another symmetry in the universe that “corrects” for this misbehavior. However, this new symmetry only appears at extremely high energies. At everyday low energies, this symmetry disappears, and to account for that, and out pops a new particle — the axion.

Now, we need to turn to string theory, which is our attempt (and has been our main attempt for 50-odd years now) to unify all of the forces of nature, especially gravity, in a single theoretical framework. It’s proven to be an especially thorny problem to solve, due to a variety of factors, not the least of which is that, for string theory to work (in other words, for the mathematics to even have a hope of working out), our universe must have more than the usual three dimensions of space and one of time; there have to be extra spatial dimensions.

These spatial dimensions aren’t visible to the naked eye, of course; otherwise, we would’ve noticed that sort of thing. So the extra dimensions have to be teensy-tiny and curled up on themselves at scales so small that they evade normal efforts to spot them.

What makes this hard is that we’re not exactly sure how these extra dimensions curl up on themselves, and there’s somewhere around 10^200 possible ways to do it.

But what these dimensional arrangements appear to have in common is the existence of axions, which, in string theory, are particles that wind themselves around some of the curled-up dimensions and get stuck.

What’s more, string theory doesn’t predict just one axion but potentially hundreds of different kinds, at a variety of masses, including the axion that might appear in the theoretical predictions of the strong nuclear force.

Silly strings

So, we have lots of new kinds of particles with all sorts of masses. Great! Could axions make up dark matter, which seems to be responsible for giving galaxies most of their mass but can’t be detected by ordinary telescopes? Perhaps; it’s an open question. But axions-as-dark-matter have to face some challenging observational tests, so some researchers instead focus on the lighter end of the axion families, exploring ways to find them.

And when those researchers start digging into the predicted behavior of these featherweight axions in the early universe, they find something truly remarkable. In the earliest moments of the history of our cosmos, the universe went through phase transitions, changing its entire character from exotic, high-energy states to regular low-energy states.

During one of these phase transitions (which happened when the universe was less than a second old), the axions of string theory didn’t appear as particles. Instead, they looked like loops and lines — a network of lightweight, nearly invisible strings crisscrossing the cosmos.

This hypothetical axiverse, filled with a variety of lightweight axion strings, is predicted by no other theory of physics but string theory. So, if we determine that we live in an axiverse, it would be a major boon for string theory.

A shift in the light

How can we search for these axion strings? Models predict that axion strings have very low mass, so light won’t bump into an axion and bend, or axions likely wouldn’t mingle with other particles. There could be millions of axion strings floating through the Milky Way right now, and we wouldn’t see them.

But the universe is old and big, and we can use that to our advantage, especially once we recognize that the universe is also backlit.

The cosmic microwave background (CMB) is the oldest light in the universe, emitted when it was just a baby — about 380,000 years old. This light has soaked the universe for all these billions of years, filtering through the cosmos until it finally hits something, like our microwave telescopes.

So, when we look at the CMB, we see it through billions of light-years’ worth of universe. It’s like looking at a flashlight”s glow through a series of cobwebs: If there is a network of axion strings threaded through the cosmos, we could potentially spot them.

In a recent study, published in the arXiv database on Dec. 5, a trio of researchers calculated the effect an axiverse would have on CMB light. They found that, depending on how a bit of light passes near a particular axion string, the polarization of that light could shift. That’s because the CMB light (and all light) is made of waves of electric and magnetic fields, and the polarization of light tells us how the electric fields are oriented — something that changes when the CMB light encounters an axion. We can measure the polarization of the CMB light by passing the signal through specialized filters, allowing us to pick out this effect.

The researchers found that the total effect on the CMB from a universe full of strings introduced a shift in polarization amounting to around 1%, which is right on the verge of what we can detect today. But future CMB mappers, such as the Cosmic Origins Explorer, Lite (Light) satellite for the studies of B-mode polarization and Inflation from cosmic background Radiation Detection (LiteBIRD), and the Primordial Inflation Explorer (PIXIE) , are currently being designed. These futuristic telescopes would be capable of sniffing out an axiverse. And once those mappers come online, we’ll either find that we live in an axiverse or rule out this particular prediction of string theory.

Either way, there’s a lot to untangle.

Paul M. Sutter is an astrophysicist at The Ohio State University, host of Ask a Spaceman and Space Radio, and author of Your Place in the Universe.

Originally published on Live Science.

China’s Lunar Rover Just Found Something Weird on the Far Side of the Moon

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China’s Lunar Rover Just Found Something Weird on the Far Side of the Moon

By Andrew Jones September 03, 2019

Tracks made by Yutu-2 while navigating hazards during lunar day 8, which occurred during late July and early August 2019.

Tracks made by Yutu-2 while navigating hazards during lunar day 8, which occurred during late July and early August 2019.
(Image: © China Lunar Exploration Project)

China’s Chang’e-4 lunar rover has discovered an unusually colored, ‘gel-like’ substance during its exploration activities on the far side of the moon.

The mission’s rover, Yutu-2, stumbled on that surprise during lunar day 8. The discovery prompted scientists on the mission to postpone other driving plans for the rover, and instead focus its instruments on trying to figure out what the strange material is.

Day 8 started on July 25; Yutu-2 began navigating a path through an area littered with various small impact craters, with the help and planning of drivers at the Beijing Aerospace Control Center, according to a Yutu-2 ‘drive diary’ published on Aug. 17 by the government-sanctioned Chinese-language publication Our Space, which focuses on space and science communication.

Related: Chang’e 4 in Pictures: China’s Mission to the Moon’s Far Side

The drive team, excited by the discovery, called in their lunar scientists. Together, the teams decided to postpone Yutu-2’s plans to continue west and instead ordered the rover to check out the strange material.

Yutu-2 found a strangely-colored substance in a crater on the far side of the moon.

Yutu-2 found a strangely-colored substance in a crater on the far side of the moon. (Image credit: China Lunar Exploration Project)

With the help of obstacle-avoidance cameras, Yutu-2 carefully approached the crater and then targeted the unusually colored material and its surroundings. The rover examined both areas with its Visible and Near-Infrared Spectrometer (VNIS), which detects light that is scattered or reflected off materials to reveal their makeup.

VNIS is the same instrument that detected tantalizing evidence of material originating from the lunar mantle in the regolith of Von Kármán crater, a discovery Chinese scientists announced in May.

Tracks showing Yutu-2's approach to the crater for analysis of the gel-like substance.

Tracks showing Yutu-2’s approach to the crater for analysis of the gel-like substance. (Image credit: China Lunar Exploration Project)

So far, mission scientists haven’t offered any indication as to the nature of the colored substance and have said only that it is “gel-like” and has an “unusual color.” One possible explanation, outside researchers suggested, is that the substance is melt glass created from meteorites striking the surface of the moon.

Yutu-2’s discovery isn’t scientists’ first lunar surprise, however. Apollo 17 astronaut and geologist Harrison Schmitt discovered orange-colored soil near the mission’s Taurus-Littrow landing site in 1972, prompting excitement from both Schmitt and his moonwalk colleague, Gene Cernan. Lunar geologists eventually concluded that the orange soil was created during an explosive volcanic eruption 3.64 billion years ago.

Strange orange soil was discovered on the moon by the Apollo 17 mission in 1972.

Strange orange soil was discovered on the moon by the Apollo 17 mission in 1972. (Image credit: China Lunar Exploration Project)

Chang’e-4 launched in early December 2018, and made the first-ever soft landing on the far side of the moon on Jan. 3. The Yutu-2 rover had covered a total of 890 feet (271 meters) by the end of lunar day 8.

Watch: China’s Historic Moon Landing Captured by Probe’s Camera

A stitched image from Yutu-2 looking back toward the Chang'e-4 lander during lunar day 7, in late June and early July 2019.

A stitched image from Yutu-2 looking back toward the Chang’e-4 lander during lunar day 7, in late June and early July 2019. (Image credit: China Lunar Exploration Project)

The Chang’e-4 lander and Yutu-2 rover powered down for the end of lunar day 8 on Aug. 7, and began their ninth lunar day over the weekend. The Yutu-2 rover woke up at 8:42 p.m. EDT on Aug. 23 (00:42 GMT Aug. 24), and the lander followed the next day, at 8:10 p.m. (00:10 GMT).

During lunar day 9, Yutu-2 will continue its journey west, take a precautionary six-day nap around local noontime, and power down for a ninth lunar night around Sept. 5, about 24 hours hours ahead of local sunset.

Follow Andrew Jones at @AJ_FI. Follow us on Twitter @Spacedotcom and on Facebook

11 Fascinating Facts About Our Milky Way Galaxy

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11 Fascinating Facts About Our Milky Way Galaxy
By Adam Mann October 16, 2018

Our Milky Way Galaxy

milky way galaxy

(Image credit: ESA/NASA/JPL-Caltech)

How much do you know about the city you live in? Sure, you’ve got your favorite restaurants and the best way to avoid traffic during rush hour, but it’s unlikely you know the details of every urban nook and cranny. The same goes for the galaxy you live in, the Milky Way.

Our celestial home is an awe-inspiring place full of stars, supernovas, nebulas, energy and dark matter, but many aspects of it remain mysterious, even to scientists. For those seeking to better know their own place in the universe, here are 11 enlightening facts about the Milky Way.

The MIlky Way’s name is ancient

milky way galaxy

(Image credit: Universal History Archive/UIG via Getty)

Before the advent of electric lights, everybody on Earth had an unobstructed view of the night sky. The enormous milky band of stars crossing it was impossible to miss. Ancient peoples gave different names to the cloud-like structure of our galaxy, but our modern version derives from the Greeks, who had a myth about the infant Hercules being brought to the goddess Hera, who nursed him while she was asleep. When she awoke and pulled away, her breast milk spilled across the heavens. The source of the Greek name itself has been lost to the ages, Matthew Stanley, a professor of the history of science at the Gallatin School of Individualized Study at New York University, previously told Live Science. “It’s one of those terms that’s so old that its origin is generally forgotten by now.”

We’re not sure exactly how many stars are in the Milky Way

milky way galaxy

(Image credit: Two Micron All-Sky Survey)

Counting stars is a tedious business. Even astronomers argue over the best way to do it. Their telescopes see only the brightest stars in our galaxy, and many are hidden by obscuring gas and dust. One technique to estimate the stellar population of the Milky Way is to look at how fast stars are orbiting within it, which gives an indication of the gravitational tug, and therefore the mass, of the galaxy. Divide the galactic mass by the average size of a star and you should have your answer. But as David Kornreich, an astronomer at Ithaca College in New York, told Live Science’s sister site, these numbers are all approximations. Stars vary widely in size, and many assumptions go into estimating the number of stars residing in the Milky Way. The European Space Agency’s Gaia satellite has mapped the location of 1 billion stars in our galaxy, and its scientists believe this represents 1 percent of the total, so perhaps the Milky Way contains about 100 billion stars. [Large Numbers That Define the Universe]

Nobody knows how much the Milky Way weighs

milky way galaxy

(Image credit: Shutterstock)

On a related note, astronomers are still unsure exactly how much our galaxy weighs, with estimates ranging from 700 billion to 2 trillion times the mass of our sun. Getting a better grasp is no easy task. Most of the Milky Way’s mass — perhaps 85 percent — is in the form of dark matter, which gives off no light and so is impossible to directly observe, according to astronomer Ekta Patel of the University of Arizona in Tucson. Her recent study looked at how strongly our galaxy’s humongous mass gravitationally tugs on smaller galaxies orbiting it and updated the estimate of the Milky Way’s mass to 960 billion times the mass of the sun, Live Science previously reported.

The Milky Way is probably in a big, empty spot in the universe

milky way galaxy

(Image credit: Springel et al./Virgo Consortium)

Several studies have indicated that the Milky Way and its neighbors are living out in the boonies of the cosmos. From afar, the large-scale structure of the universe looks like a colossal cosmic web, with string-like filaments connecting dense regions separated by enormous, mostly empty voids. The emphasis in that last sentence should be on “mostly empty,” since our own galactic abode seems to be an inhabitant of the Keenan, Barger and Cowie (KBC) Void, named after three astronomers who identified it in a 2013 study in The Astrophysical Journal. Last year, a separate team looked at the motion of galaxies in the cosmic web to provide additional confirmation that we’re floating in one of the big, empty areas, Live Science previously reported.

Astronomers are trying to photograph the monster black hole at the Milky Way’s center

milky way galaxy

(Image credit: NASA/CXC/Columbia Univ./C. Hailey et al.)

Lurking in the heart of our galaxy is a hungry behemoth, a gigantic black hole with the weight of 4 million suns. Scientists know that it’s there because they can trace the paths of stars in the Milky Way’s center and see that they seem to orbit a supermassive object that can’t be seen. But in recent years, astronomers have been combining observations from multiple radio telescopes to try and get a glimpse of the environment surrounding the black hole, which is packed with gas and dust spinning around the black hole’s maw. The project, called the Event Horizon Telescope, expects to have preliminary images of the black hole’s edge in the coming months, according to the team’s blog. [Stephen Hawking’s Most Far-Out Ideas About Black Holes]

Small galaxies orbit the Milky Way and sometimes crash into it

milky way galaxy

(Image credit: Juan Carlos Muñoz/ESO)

When Portuguese explorer Ferdinand Magellan sailed through the Southern Hemisphere in the 16th century, he and his crew were among the first Europeans to report on circular clusters of stars in the night sky, according to the European Southern Observatory. These clusters are actually small galaxies that orbit our Milky Way like planets around a star, and they have been named the Small and Large Magellanic clouds. Many such dwarf galaxies orbit ours — and sometimes they get eaten by our massive Milky Way. Earlier this year, astronomers used new data from the Gaia satellite that showed millions of stars in our galaxy moving in similar narrow, “needle-like” orbits, suggesting they all originated from an earlier dwarf galaxy dubbed “the Gaia Sausage,” as Live Science reported at the time.

The Milky Way is full of toxic grease

milky way galaxy

(Image credit: NASA/JPL-Caltech)

Swirling through the mostly empty space between stars in our galaxy is a bunch of dirty grease. Oily organic molecules known as aliphatic carbon compounds are produced in certain types of stars and then are leaked out into interstellar space. A recent study found that these grease-like substances could account for between a quarter and one-half of the Milky Way’s interstellar carbon — five times more than previously believed, as Live Science reported in June. Though strange, the findings are cause for optimism, according to researchers. Because carbon is an essential building block of living things, finding it in abundance throughout the galaxy could suggest that other star systems harbor life.

The Milky Way is going to crash with its neighbor in 4 billion years

milky way galaxy

(Image credit: Shutterstock)

Sad to say, but our galaxy isn’t going to be here forever. Astronomers know that we are currently speeding toward our neighbor, the Andromeda galaxy, at around 250,000 mph (400,000 km/h). When the crash comes, in about 4 billion years, most research has suggested that the more massive Andromeda galaxy would swallow up our own and survive. But in a recent study, astronomers reweighed Andromeda and found that it was roughly equivalent to 800 billion suns, or about on par with the Milky Way’s mass, as Live Science previously reported. That means that exactly which galaxy will emerge less scathed from the future galactic crash remains an open question.

Stars from our galactic neighbors are racing toward the Milky Way

milky way galaxy

(Image credit: ESA/Marchetti et al 2018/NASA/ESA/Hubble/CC BY-SA 3.0 IGO)

Movie stars in films are known to swap spit, but who knew that galaxies in the universe sometimes swap stars? Researchers were recently searching for hypervelocity stars, which get thrown at mind-bending speeds from the Milky Way after interacting with the giant black hole in its center. What they found was even stranger — rather than flying away from our galaxy, most of the fast stars they spotted were barreling toward us. “These could be stars from another galaxy, zooming right through the Milky Way,” Tommaso Marchetti, an astronomer at Leiden University in the Netherlands, said in a statement. In the study, which was published Sept. 20 in the journal Monthly Notices of the Royal Astronomical Society, the authors suggest that these odd stars could have originated in the Large Magellanic Cloud or some other galaxy farther away and write in their paper that the discovered objects “may constitute the tip of the iceberg” of a large population of similar stars.

There are mysterious bubbles arising out of the Milky Way

milky way galaxy

(Image credit: NASA Goddard)

Imagine discovering that your living room, which you’ve seen a million times before, contained a previously unnoticed elephant. That’s more or less what happened to scientists in 2010 when they uncovered gigantic, never-before-seen structures stretching for 25,000 light-years above and below the galaxy. Named ‘Fermi bubbles’ after the telescope that found them, these gamma-ray-emitting objects have defied astronomers’ explanations ever since. Last year, a team gathered evidence suggesting that the bubbles are the aftermath of an energetic event 6 million to 9 million years ago, when the supermassive black hole in the galactic center swallowed a huge clump of gas and dust and burped out the giant, glowing clouds, according to NASA.

Our galaxy is being bombarded with bizarre energy pulses from the other side of the universe

milky way galaxy

(Image credit: OzGrav Swinburne University of Technology)

Over the last decade, astronomers keep detecting odd flashes of light coming at them from the distant cosmos. Known as fast radio bursts (FRBs), these mysterious signals have no agreed-upon explanation. Despite knowing about them for more than 10 years, researchers had until recently captured only 30 or so examples of these FRBs. But in a recent study, Australian scientists managed to find 20 more FRBs, nearly doubling the number of known objects, as Live Science previously reported. While they still don’t know the odd flashes’ origin, the team was able to determine that the light had traveled through several billion light-years of gas and dust, which imparted telltale signs on the signal, suggesting that the FRBs were coming from quite a long way off.

A Second Interstellar Visitor Has Arrived in Our Solar System. This Time, Astronomers Think They Know Where It Came From

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A Second Interstellar Visitor Has Arrived in Our Solar System. This Time, Astronomers Think They Know Where It Came From

By Rafi Letzter – Staff Writer October 09, 2019
When ‘Oumuamua passed through our solar system in 2017, no one could figure out where the object came from. But astronomers think they’ve worked out how Comet 2I/Borisov got here.

An artist's depiction of the first identified interstellar object, 'Oumuamua.

An artist’s depiction of the first identified interstellar object, ‘Oumuamua.
(Image: © M. Kornmesser/ESO)

For the second time ever, astronomers have detected an interstellar object plunging through our solar system. But this time, researchers think they know where it came from.
Gennady Borisov, an amateur astronomer working with his own telescope in Crimea, first spotted the interstellar comet on Aug. 30. His find made the object the first interstellar visitor discovered since oblong ‘Oumuamua flashed through our solar neighborhood back in 2017. Now, in a new paper, a team of Polish researchers has calculated the path this new comet — known as Comet 2I/Borisov or (in early descriptions) as C/2019 Q4 — took to arrive in our sun’s gravity well. And that path leads back to a binary red dwarf star system 13.15 light-years away, known as Kruger 60.
When you rewind Comet Borisov’s path through space, you’ll find that 1 million years ago, the object passed just 5.7 light-years from the center of Kruger 60, moving just 2.13 miles per second (3.43 kilometers per second), the researchers wrote.

That’s fast in human terms —— about the top speed of an X-43A Scramjet, one of the fastest aircraft ever built. But an X-43A Scramjet can’t overcome the sun’s gravity to escape our solar system. And the researchers found that if the comet were really moving that slowly at a distance of no more than 6 light-years from Kruger 60, it probably wasn’t just passing by. That’s probably the star system it came from, they said. At some point in the distant past, Comet Borisov lively orbited those stars the way comets in our system orbit ours.
Ye Quanzhi, an astronomer and comet expert at the University of Maryland who wasn’t involved in this paper, told Live Science that the evidence pinning Comet 2I/Borisov to Kruger 60 is pretty convincing based on the data available so far.
“If you have an interstellar comet and you want to know where it came from, then you want to check two things,” he said. “First, has this comet had a small pass distance from a planetary system? Because if it’s coming from there, then its trajectory must intersect with the location of that system.”
Though the 5.7 light-years between the new comet and Kruger may seem bigger than a “small gap” — nearly 357,000 times Earth’s distance from the sun — it’s close enough to count as “small” for these sorts of calculations, he said.
“Second,” Ye added, “usually comets are ejected from a planetary system due to gravitational interactions with major planets in that system.”
In our solar system, that might look like Jupiter snagging a comet that’s falling toward the sun, slingshotting it around in a brief, partial orbit and then flinging it away toward interstellar space.
“This ejection speed has a limit,” Ye said. “It can’t be infinite because planets have a certain mass,” and the mass of a planet determines how hard it can throw a comet into the void. “Jupiter is pretty massive,” he added, “but you can’t have a planet that’s 100 times more massive than Jupiter because then it would be a star.”
Related: 15 Amazing Images of Stars
That mass threshold sets an upper limit on the speeds of comets escaping star systems, Ye said. And the authors of this paper showed that Comet 2I/Borisov fell within the minimum speed and distance from Kruger 60 to suggest it originated there —assuming their calculations of its trajectory are correct.
Studying interstellar comets is exciting, Ye said, because it offers a rare opportunity to study distant solar systems using the precise tools scientists employ when examining our own. Astronomers can look at Comet 2I/Borisov using telescopes that might reveal details of the comet’s surface. They can figure out whether it behaves like comets in our own system (so far, it has) or does anything unusual, like ‘Oumuamua famously did. That’s a whole category of research that usually isn’t possible with distant solar systems, where small objects only ever appear —— if they’re visible at all —— as faint, discolored shadows on their suns.
This research, Ye said, means that anything we learn about Comet Borisov could be a lesson about Kruger 60, a nearby star system where no exoplanets have been discovered. ‘Oumuamua, by contrast, seems to have come from the general direction of the bright star Vega, but according to NASA’s Jet Propulsion Laboratory, researchers don’t believe that’s where the object originally came from, instead suggesting it likely came from a newly-forming star system (though researchers aren’t sure which one).. That would make Comet Borisov the first interstellar object ever traced to its home system, if these results are confirmed.
However, the paper’s authors were careful to point out that these results shouldn’t yet be considered conclusive. Astronomers are still collecting more data about Comet 2I/Borisov’s path through space, and additional data may reveal that the original trajectory was wrong and that the comet came from somewhere else.
The paper tracing the comet’s origin has not yet been published in a peer-reviewed journal, but it’s available on the preprint server arXiv.

In Images: Rising ‘Phoenix’ Aurora and Starburst Galaxies Light Up the Skies

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In Images: Rising ‘Phoenix’ Aurora and Starburst Galaxies Light Up the Skies
By Christine Lunsford June 25, 2019

Aurora Bird astronomy photographers

(Image credit: Copyright Alexander Stepanenko)

Russian photographer Alexander Stepanenko visited the Murmansk region in Russia for years, attempting to capture an image of the aurora over an abandoned military hydroelectric station. Stepanenko’s patience finally paid off on Sept. 10, 2018. This and other photos were recently selected for the shortlist of the Astronomy Photographer of the Year contest, organized by the Royal Observatory, Greenwich in the United Kingdom.

Read more about the “phoenix aurora” and other incredible astronomy photos.

Aurora outside the tiny cave

Aurora outside a tiny cave astronomy photographers

(Image credit: Copyright Sutie Yang)

In Seljalandsfoss, Iceland, on Jan. 8, 2019, Chinese photographer Sutie Yang caught a mesmerizing view of an aurora from inside a cavern, framing the aurora alongside Iceland’s Seljalandsfoss waterfall.

Deep in the heart of Mordor

Deep in the heart of Mordor astronomy photographers

(Image credit: Copyright Andrew Campbell)

Australian photographer Andrew Campbell captured NGC 7293 — the Helix Nebula — one of the brightest and closest examples of a gas cloud created at the end of the life of a sun-like star. The remnant of the star’s core is still so energetic that it causes the previously expelled gas to fluoresce in glowing rings. Campbell created this colorful composite image from an exposure lasting 63 hours and 58 minutes, taken in Melbourne, Australia on Nov. 27, 2018.

Devil’s Head Nebula

Depth and height of NGC 7822 astronomy photography

(Image credit: Copyright Laszlo Bagi)

For this image of the Devil’s Head Nebulae Complex, Hungarian photographer László Bagi used custom-built Newtonian reflecting telescope with an exposure of 29 hours, highlighting the nebula’s structure and depth. Bagi captured the photo in Szarvas, Hungary on Oct. 10, 2018.

Gum 12

Gum 12 astronomy photographers

(Image credit: Copyright Eddie Trimarchi)

The Gum Nebula, or Gum 12, is an emission nebula that extends 36 degrees across the night sky and is actually the very large remnant of the 12,000-year-old Vela supernova. The nebula mostly consists of hydrogen (red) and doubly ionized oxygen (blue). Australian photographer Eddie Trimarchi captured this bi-color image at Biggera Waters, Australia, on Feb. 25, 2018.

The Horsehead and Flame Nebula

The Horsehead and Flame Nebula astronomy photogrpahers

(Image credit: Copyright Conner Matherne)

American photographer Connor Matherne’s astonishing view of the Horsehead and Flame Nebulae was captured from the Deep Sky West Observatory in Rowe, New Mexico on Nov. 27, 2018. According to Matherne, his image was inspired by astrophotographer Ken Crawford’s image of the Horsehead Nebula, showcasing hydrogen filaments located within the blue nebula — NGC 2023 —, just below the Horsehead.

The Lord of the Rings and his court

The Lord of the Rings and his court astronomy photographers

(Image credit: Copyright Jordi Delpeix Borrell)

Spanish photographer Jordi Delpeix Borrell’s image features Saturn’s magnificent rings shining broad and bright alongside several of its bright satellites. Titan appears at the bottom right, Rhea is on the top left, Tethys and Dione are to the right of the planet, and Enceladus and Mimas are under the rings. Borrell photographed the planet and moons from Long Bay, Barbados on July 5, 2018.


orion astronomy photographers

(Image credit: Copyright Raul Villaverde Fraile)

Photographer Raul Villaverde Fraile of Spain captured one of the most photographed astronomical objects — the Orion Nebula — in an exposure lasting 33 hours and 45 minutes. The image was taken on Jan. 6, 2019, at Ocentejo, Castile-La Mancha, Spain.

Out on a Limb

Out on a Limb astronomy photographers

(Image credit: Copyright Alastair Woodward)

British photographer Alastair Woodward snapped this image of a solitary prominence on the limb of the solar disk from Derby, UK on July 8, 2019. The photographer inverted the image during processing to show both the prominence and details of the chromosphere — the second of three layers in the sun’s outer atmosphere. The image represents approximately 700 frames from a movie shot at 40 frames per second.

The Running Man Nebula

The Running Man Nebula astronomy photographers

(Image credit: Copyright Steven Mohr)

From Carapooee, Victoria, Australia, Australian photographer Steven Mohr snapped the Running Man Nebula on Jan. 15, 2019. The Running Man Nebula lies in the constellation of Orion, located some 1,500 light years from Earth.

The Sculptor Galaxy

The Sculptor Galaxy astronomy photographers

(Image credit: Copyright Bernard Miller/Martin Pugh)

Photographers Bernard Millar and Martin Pugh of the U.S. snapped the Sculptor Galaxy, also known as NGC 253, from Yass, New South Wales, Australia on Nov. 12, 2018. This is a starburst galaxy, which means it undergoes periods of intense star formation, and it is the largest galaxy in a cluster of galaxies called the Sculptor Group.

Seven-colour feather of the moon

Seven-colour feather of the moon astronomy photographers

(Image credit: Copyright Yiming Li)

Chinese photographer Yiming Li’s breathtaking image showcases the Moon’s elegant corona. Highlighted by clouds, this lunar view was captured in Dongguan, China on July 28, 2018.

A Titanium moon

Titanium moon astronomy photographers

(Image credit: Miguel Claro)

Photographer Miguel Claro of Portugal captured a stunning image of Earth’s moon from the Dark Sky Observatory in Alqueva, Portugal on Oct. 25, 2018.

Read more about the “phoenix aurora” and other incredible astronomy photos



Violent Solar Storms Are Happening Closer to Earth Than Anyone Thought Was Possible

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Violent Solar Storms Are Happening Closer to Earth Than Anyone Thought Was Possible

By Yasemin Saplakoglu – Staff Writer a day ago
The spectacular solar storms that paint the polar skies in beautiful greens and pinks have a darker side.

This aurora was captured on camera from the International Space Station on June of 2017.

This aurora was captured on camera from the International Space Station in June 2017.
(Image: © NASA)

The spectacular solar storms that paint the polar skies in beautiful greens and pinks have a darker side: They have the power to wreak havoc on our electrical grid, communication systems and satellites. Now, a new study suggests that the source of these solar storms is much closer to our planet than previously thought.
Earth is shielded by a protective bubble known as the magnetosphere which blocks harmful solar radiation. But when the sun occasionally emits high-speed streams of radiation — and, with it, intense magnetic field lines — they can strongly interact with our planet’s own magnetic field.

As this solar wind hits the magnetosphere, the two sets of magnetic field lines become entangled. This interaction generates heat and accelerates the charged particles — ions and electrons— brought in by the solar wind, temporarily weakening the planet’s magnetic field and creating powerful magnetic storms that appear to us as auroras.

But because these storms are rare, and there aren’t enough satellites to observe them, it’s not clear exactly where and how this reconnection of magnetic field lines happened, the study’s researchers said in a statement.
To figure that out, the researchers used observations from NASA’s Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites. During solar storms, these satellites sit at Earth’s magnetotail — the part of the magnetosphere on the side of the planet not facing the sun — which becomes elongated by the solar wind. The researchers found that this magnetic reconnection — the event that sparks magnetic storms — can occur much closer to our planet than previously thought: about three to four Earth diameters away, according to the statement.

This artist's rendition shows what happens in Earth's magnetosphere during a magnetic storm. The three THEMIS satellites observed the reconnection of magnetic field lines close to the geosynchronous orbit. The reconnection site (X) created outflows of energized particles towards and away from the planet. The particles that went toward the planet carried energy along the magnetic field lines to power auroras at the planet's poles and were detected by the GOES weather satellite (left of the arrow).
This artist’s illustration shows what happens in Earth’s magnetosphere during a magnetic storm. The three THEMIS satellites observed the reconnection of magnetic field lines close to the geosynchronous orbit. The reconnection site (X) created outflows of energized particles towards and away from the planet. The particles that went toward the planet carried energy along the magnetic field lines to power auroras at the planet’s poles and were detected by the a weather satellite (left of the arrow). (Image credit: Emmanuel Masongsong/UCLA)

What’s more, a weather satellite in a near-Earth orbit (or geosynchronous orbit) detected energized electrons following the storm, suggesting that the reconnection event prompted ions and electrons to accelerate to high energies. The electrons that flow toward the planet carry energy along magnetic field lines to create the auroras we see.
This acceleration can be hazardous to the hundreds of satellites moving in geosynchronous orbit and also can be harmful to human DNA, thereby posing a risk to astronauts, according to the statement.
Moreover, solar storms can impact Earth-dwellers in significant ways. In 1921, for example, a magnetic storm disrupted telegraph communications and caused power outages that led to the burning of a train station in New York City, according to the statement.
“By studying the magnetosphere, we improve our chances of dealing with the greatest hazard to humanity venturing into space: storms powered by the sun,” lead author Vassilis Angelopoulos, a professor of space physics at UCLA, said in the statement. These findings might help astronauts and Earth-dwellers to better prepare for dangerous solar weather.
The findings were published Jan. 13 in the journal Nature Physics.