Bizarre 500-Million-Year-Old Creature Unearthed


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Bizarre 500-Million-Year-Old Creature Unearthed

Tia Ghose, LiveScience Staff Writer
Date: 25 June 2013 Time: 08:01 PM ET
During the Cambrian explosion, the diversity of life exploded and bizarre sea creatures such as the Helcocystis moroccoensisflourished.
CREDIT: Andrew Smith

A new fossilized, cigar-shaped creature that lived about 520 million years ago has been unearthed in Morocco.

The newfound species,Helicocystis moroccoensis, has “characteristics that place it as the most primitive echinoderm that has fivefold symmetry,” said study co-author Andrew Smith, a paleontologist at the Natural History Museum in London, referring to the group of animals that includesstarfish and sea urchins. Modern echinoderms typically have five-point symmetry, such as the five arms of the starfish or the sand dollar’s distinctive pattern.

The primitive sea creature, described today (June 25) in the journal Proceedings of the Royal Society B, could even change its body shape from slender to stumpy. Researchers say it is a transitional animal that could help explain how early echinoderms evolved their unique body plans, Smith said. [Photos of Newfound Species & Other Cambrian Creatures]

Cambrian explosion

In 2012, Smith and his colleagues were excavating in sediments dating to about 520 million years ago in the Anti-Atlas Mountains in Morocco, when they uncovered several specimens of the strange fossil.

The creature lived on the ancient supercontinent called Gondwana during the Cambrian Explosion, a period when all creatures inhabited the seas and life on the planet diversified dramatically.

One of the oldest known echinoderms, Helicoplacus — first unearthed in the White Mountains in California — had a spiral but asymmetrical body plan. And all modern echinoderms start off as larvae with bilateral symmetry, raising the question of how and when the creatures’ distinctive five-point body plan originated.

New creatures

H. moroccoensis, named after the country where it was found, had a cylindrical body that extended up to 1.6 inches (4 centimeters) long. The echinoderm’s mouth was on the top of its body, and it sported a cup made of checkered plates with a small stem at its base. It had a latticelike skeleton made of calcite.

“It’s a cigar-shaped beast, and it was able to expand and contract that cigar shape,” Smith told LiveScience. “Sometimes it could be short and fat, and sometimes it could be long and thin.”

The tiny sea creatures changed shape using a spiraling arrangement of five ambulacra, or grooves coming from the mouth that opened and closed to capture bits of food floating in the water.

The newly discovered species is the oldest known echinoderm with five ambulacra, and could shed light on how echinoderms evolved their unique body plans, Smith said.

H. moroccoensis was also found in sediments containing several other bizarre echinoderms, many of which had wacky body plans, ranging from completely asymmetrical to bilaterally symmetrical. That wide variety suggests the creatures were going through a period of dramatic diversification around that time period, Smith said.

“The important thing about the whole fauna is that there is already, by this time, a remarkable diversity in body form,” Smith said. “And yet this is only 10 [million] to 15 million years after the calcite skeleton evolved.”

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What Is Sarin?


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What Is Sarin?

By Elizabeth Palermo, Life’s Little Mysteries Contributor
Date: 25 June 2013 Time: 05:16 PM ET
Sarin gas is a deadly terrorism weapon.
CREDIT: Ensuper | Shutterstock.com

Sarin is a man-made, lethal toxin with no color, taste or odor. Though it’s produced as a liquid, its low evaporation point lets it turn into a gas quickly when it’s exposed to the environment.

Sarin, also known as GB by military personnel, was originally developed as a pesticide in Germany in 1938, but since then, it has been classified by many national governments as a chemical nerve agent. Nerve agents are the most toxic and fast-acting chemical warfare agents in the world.

Like the organophosphate pesticides with which it shares much of its molecular structure, sarin prevents the body from “turning off” glands and muscles, which means these parts of the body are constantly stimulated. Even a small drop of sarin on the skin can cause someone to twitch and sweat profusely.

People exposed to large amounts of sarin quickly lose control over their bodily functions and, if not treated immediately, can fall into a coma or succumb to respiratory failure.

Sarin gas can be inhaled or absorbed through the skin or eyes. In its liquid form, sarin mixes easily with water and can be deadly if ingested.

Despite these dangers, the chemicals that make up this deadly compound are commercially available in some countries. The sarin-production process is complicated and extremely dangerous, but that hasn’t deterred the terrorist groups that have made and used the toxin.

In two attacks — one in 1994 and one in 1995 — a religious cult in Japan released sarin into subway stations, killing 21 people, injuring hundreds and causing nearly a thousand others to suffer temporary vision problems.

Sarin has also been used as a chemical weapon by government and military groups. In 1988, the Iraqi government used sarin as a chemical weapon in the Kurdish town of Halabja, killing between 3,000 and 5,000 people, and injuring thousands more.

Most recently, sarin is believed to have been used this year by the Syrian government against rebels in that country’s civil war.

Woman Drinks Only Soda for 16 Years, Suffers Heart Problems


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Woman Drinks Only Soda for 16 Years, Suffers Heart Problems

LiveScience.comBy Rachael Rettner, LiveScience Senior Writer | LiveScience.com – 20 hrs ago

A cashier rings up A&W TEN for a customer shopping at Minyard's Food Store, on Thursday, February, 7, 2013 in Dallas, Texas. Consumers are counting calories more than ever, and beverage companies are responding with new low-calorie options. In January, Dr Pepper Snapple Group began rolling out ten-calorie versions of five of its most popular soft drink brands including Canada Dry TEN, Sunkist TEN Soda, RC TEN and 7-UP TEN. (Brandon Wade / AP Images for Dr Pepper Snapple Group)

Associated Press – A cashier rings up A&W TEN for a customer shopping at Minyard’s Food Store, on Thursday, February, 7, 2013 in Dallas, Texas. Consumers are counting calories more than ever, and beverage companies are responding with new low-calorie options. In January, Dr Pepper Snapple Group began rolling out ten-calorie versions of five of its most popular soft drink brands including Canada Dry TEN, Sunkist TEN Soda, RC TEN and 7-UP TEN. (Brandon Wade / AP Images for Dr Pepper Snapple Group)

A 31-year old woman’s heart problems and fainting might have had something to do with the fact that she drank only soda for about half her life, according to a report of her case.

The woman, who lives in Monaco, a small country near southern France, was brought to a hospital after she fainted. A blood test showed she had severely low potassium levels. And a test of her heart’s electrical activity revealed she had a condition called long QT syndrome, which can cause erratic heart beats.

The woman did not have a family history of heart or hormone problems. But she told her doctors that, since the age of 15, she had not drunk any water — soda (specifically cola) was the only liquid she consumed. She drank about 2 liters (2 quarts) of cola daily, she said.

After abstaining from soda for just one week, the woman’s potassium levels and heart electrical activity returned to normal.

Drinking too much cola may cause excess water to enter the bowels, which in turn leads to diarrhea, and loss of potassium, the researchers said. High amounts of caffeine can also increase urine production and decrease potassium reabsorption, the researchers said. Potassium plays a role in helping a person’s heartbeat, and low levels of potassium may cause heart rhythm problems.

After searching for other similar cases, the researchers found six reports of excessive cola consumption that were thought to be related to adverse medical problems, including heart rhythm problems.

“One of the take-home messages is that cardiologists need to be aware of the connection between cola consumption and potassium loss, and should ask patients found to have QT prolongation about beverage habits,” said study researcher Dr. Naima Zarqane, of Princess Grace Hospital Centre in Monaco.

Future studies should examine whether those who drink cola excessively have lower potassium levels than people who don’t drink cola, the researchers said.

Excessive soda consumption can also lead to weight gain, which is a risk factor for heart disease, the researchers said.

The case report was presented this week at the European Heart Rhythm Association meeting in Athens, Greece. It has not been published in a peer-reviewed journal.

Pink dolphin dazzles in Brazil


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Pink dolphin dazzles in Brazil

http://news.yahoo.com/lightbox/rare-pink-dolphins-in-brazil-1372183681-slideshow/pink-dolphin-photo-2088523462.html

Tourist Michel Watson found this pink dolphin making a splash in Brazil. The unusual creature, which hides deep in the Rio Negro river, was spotted leaping out of the Amazonian water brandishing its bizarre bright bubblegum color. Weighing in at nearly 300 pounds, the curious animal, known as an Amazon Pink River Dolphin, looked unusually agile as it rose above the waves.
A pink dolphin shows off for the camera in Brazil.

Senior Loneliness


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Senior Loneliness

The Risks of Loneliness and Senior Neglect

By , Caring.com senior editor
Last updated: June 20, 2013
elderlonely

Here’s an all-too-common scenario: A senior in your life is becoming increasingly isolated, and you worry that he or she is lonely, but you’re not sure what to do. It’s not the easiest subject to bring up, especially when family members or loved ones are proud and don’t want to admit they’re feeling alone.

But with one of out of eight Americans now over 65 (more than 41 million people as of 2012), loneliness and isolation are becoming hot-button issues for all of us. Consider these facts, from the Administration on Aging:

  • Twenty-eight percent of Americans over 65 live alone; for women, it’s a startling 46 percent.
  • People over 65 have an average life expectancy of almost 20 more years.
  • While 72 percent of men over 65 are married, only 45 percent of women are married; 37 percent are widows.
  • Almost half of women over 75 live alone.

Lack of contact with others is a serious issue among seniors, social services experts say. Sometimes an older adult lacks a network of family and friends; other times seniors may withdraw into isolation as a result of health conditions, depression, or mental illness. Physical limitations such as a fear of falling can keep a senior isolated in her home, as can fatigue, chronic pain, or shame over memory problems. Many seniors become nervous about driving long distances or can no longer drive after dark, and they may fear or resist using public transportation options.

As a result of these factors, older adults may be alone for days or even weeks; a recent survey in England found that one-fifth of adults over 75 reported having contact with another person less than once a week, and one in ten said they might see a visitor less than once a month. In a 2009 Pew Research report, one out of every six Americans over 65 described their lives as lonely.

Sadly, loneliness can accompany more serious forms of neglect and abandonment — both of which are considered elder abuse as defined by the National Center on Elder Abuse (NCEA). The termneglect refers to any situation in which a senior doesn’t have the food, healthcare, shelter, and protection he or she needs, including help with the tasks necessary for daily living. Abandonmentoccurs when those who’ve assumed responsibility for care or custody of a senior stop providing it, whether intentionally or through oversight or lack of means.

Whether or not a senior in your life is lonely or socially isolated, this epidemic of loneliness is a society-wide problem that affects all of us. When you’re frustrated with the elderly woman ahead of you holding up the checkout line while she chats with the checker, ask yourself: What if that’s the only conversation she’ll have all day, or even all week? As a society, we should be treating senior loneliness as the public health crisis it is, experts say, because of the profound effects loneliness can have on physical and mental health.

And if you’re concerned about an older family member or friend who seems lonely, your worry is well-founded. Isolation and loneliness are prime signs that an older adult is without the support and tools needed to live a healthy, independent life and may be in danger of spiraling into decline.

Fact: Loneliness Harms Your Brain

Interesting new research is showing that loneliness may speed up the onset of dementia. In a recent Dutch study published in the Journal of Neurology, Neurosurgery, and Psychiatry, researchers followed more than 2,000 healthy, dementia-free seniors for three years and found that 13 percent who reported feeling lonely developed dementia by the end of that time, as compared with 6 percent with strong social support.

Fact: Loneliness Harms Your Heart

In 2012, the Journal of the American Medical Association (JAMA) compiled the results of numerous studies and concluded that there’s a proven link between loneliness and fatal heart disease. In one study cited, researchers at Harvard followed 44,000 people with heart disease and found that 8 percent of patients who lived alone died after four years, compared with 5.7 of those who lived with a spouse or others.

In research on the outcomes of coronary disease, Swedish researchers discovered that coronary bypass patients who checked the box “I feel lonely” had a mortality rate 2.5 times higher than other patients 30 days post-surgery, and that even five years later they were twice as likely to have died.

Fact: Loneliness Kills

Can this really be true? Sadly, yes. When researchers at the University of California, San Francisco, followed a group of seniors for six years, they found that by the end of the study period, almost a quarter (22.8 percent) of all the older adults who had reported feeling isolated or lonely had died. And another 25 percent had suffered significant health declines. By comparison, among the seniors who said they were happy or satisfied with their social lives, only 12.5 percent had declining health, and only 14.2 percent had died.

And before you dismiss this type of isolation as common only among the very old, consider that the average age of the adults in the study was just 71. In other words, many baby boomers are reaching retirement age without strong social networks to support them.

Another study, this time from Brigham Young University, analyzed study data for more than 300,000 people and found that loneliness was as strong a marker for early death as alcoholism and heavy (more than 15 cigarettes a day) smoking.

senior-social-media

What can you do if an older adult in your life is growing isolated or lonely? Here are four simple steps you can take to help your loved one reconnect.

  1. Help your loved one become more social-media savvy.
    As younger folks know all too well, you don’t need to leave your house to catch up with friends, follow current events, and find out about events in your area. E-mail and news sites are one way to do this, of course, but using a social media site like Facebook makes it even easier for an older adult to feel connected, simply by being able to see what others are posting. Facebook also offers plenty of opportunities to participate in “watercooler” discussions of current goings-on and share recommendations for books, movies, and music. Ask yourself: Don’t you feel more motivated to get out and see a movie if your friends are talking about it? The same is true for your parent or loved one.
  2. Encourage your loved one not to live alone.
    It’s common for seniors to want to “age in place” in their own homes, and you may hear strong opinions on this topic from your parents and older loved ones. But this may not be such a good idea, experts say; studies show that those who live alone are prone to a host of health issues compared with those who are married or living in a group living situation.A Dutch study published in the Journal of Neurology, Neurosurgery, and Psychiatry showed that people who lived alone or who were no longer married were between 70 percent and 80 percent more likely to develop dementia than those who lived with others or were married. And a recent study conducted at University College London found that social isolation — even more than loneliness — can lead to early death, even for those as young as 52.
  3. Set up transportation options.
    Ask anyone who works with seniors living on their own: One of the biggest factors behind isolation is lack of transportation. Many older adults no longer drive, or they fear driving at night or on unfamiliar routes. Call your local Area Agency on Aging and get a list of all the transportation resources in your loved one’s area. If, despite your encouragement, your loved one resists using group transportation, consider setting up a taxi fund so that taking a taxi doesn’t feel like too much of a splurge. Another possibility: Find a taxi driver in your area whom your parent feels comfortable with and set up regular appointments for your loved one’s activities.
  4. Help your loved one find support groups.
    When older adults with health problems find support from others with the same condition, it helps with loneliness and depression. They may also get valuable information and motivation to seek help for their health condition. The University of College London researchers noted that the early death rate for socially isolated people may be due to the fact that they don’t have anyone to encourage them to get help with health problems or to intervene in a health crisis. If your loved one has physical impairments, an online support group can ease anxiety and inspire him with ideas for ways to help himself. If your loved one is a widower or widow, a bereavement or grief support group offers a chance to share feelings as well as a place to meet others in the same situation.

Chandra Latest News, Features and Photos


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Chandra Latest News, Features and Photos

http://www.nasa.gov/mission_pages/chandra/main/index.html

Data from the NASA Chandra Xray Observatory has been used to discover 26 black hole candidates in Andromeda, the galactic neighbor to the Milky Way.

Data from NASA’s Chandra X-ray Observatory have been used to discover 26 black hole candidates in the Milky Way’s galactic neighbor, Andromeda, as described in our latest press release. This is the largest number of possible black holes found in a galaxy outside of our own.

A team of researchers, led by Robin Barnard of the Harvard-Smithsonian Center for Astrophysics, used 152 observations of Chandra spanning over 13 years to find the 26 new black hole candidates. Nine were known from earlier work. These black holes belong to the stellar-mass black hole category, which means they were created when a massive star collapsed and are about 5 to 10 times the mass of the Sun.

This wide-field view of Andromeda contains optical data from the Burrell Schmidt telescope of the Warner and Swansey Observatory on Kitt Peak in Arizona. Additional detail of the core and dust in the spiral arms comes from an image taken by astrophotographer Vicent Peris using data from two of his personal telescopes. In this combined optical image, red, green, and blue show different bands from the visible light portion of the electromagnetic spectrum.

The inset contains X-ray data from multiple Chandra observations of the central region of Andromeda. A larger view can be seen in the Chandra image at this link.

Seven of the 35 black hole candidates are within only 1,000 light years of the Andromeda Galaxy’s center. This is more than the number of black hole candidates with similar properties located near the center of our own Galaxy. This, however, does not take astronomers by surprise, since the bulge of stars in the middle of Andromeda is bigger, allowing more black holes to form.

Eight of the nine black hole candidates that were previously identified are associated with globular clusters, the ancient concentrations of stars distributed in a spherical pattern about the center of the galaxy. This also differentiates Andromeda from the Milky Way as astronomers have yet to find a similar black hole in one of the Milky Way’s globular clusters.

Andromeda, also known as Messier 31 (M31), is a spiral galaxy located about 2.5 million light years away. It is thought that the Milky Way and Andromeda will collide several billion years from now. The black holes located in both galaxies will then reside in the large, elliptical galaxy that results from this merger.

These results are available online and will be published in the June 20th issue of The Astrophysical Journal. Many of the Andromeda observations were made within Chandra’s Guaranteed Time Observer program.

Credits: X-ray: NASA/CXC/SAO/R. Barnard, Z. Lee et al.; Optical: NOAO/AURA/NSF/REU Program/B. Schoening, V. Harvey and Descubre Foundation/CAHA/OAUV/DSA/V. Peris

Magnetar SGR 0418-5729, left, and artist concept, right

This graphic shows an exotic object in our galaxy called SGR 0418+5729 (SGR 0418 for short). As described in our press release, SGR 0418 is a magnetar, a type of neutron star that has a relatively slow spin rate and generates occasional large blasts of X-rays.

The only plausible source for the energy emitted in these outbursts is the magnetic energy stored in the star. Most magnetars have extremely high magnetic fields on their surface that are ten to a thousand times stronger than for the average neutron star. New data shows that SGR 0418 doesn’t fit that pattern. It has a surface magnetic field similar to that of mainstream neutron stars.

In the image on the left, data from NASA’s Chandra X-ray Observatory shows SGR 0418 as a pink source in the middle. Optical data from the William Herschel telescope in La Palma and infrared data from NASA’s Spitzer Space Telescope are shown in red, green and blue.

On the right is an artist’s impression showing a close-up view of SGR 0418. This illustration highlights the weak surface magnetic field of the magnetar, and the relatively strong, wound-up magnetic field lurking in the hotter interior of the star. The X-ray emission seen with Chandra comes from a small hot spot, not shown in the illustration. At the end of the outburst this spot has a radius of only about 160 meters, compared with a radius for the whole star of about 12 km.

The researchers monitored SGR 0418 for over three years using Chandra, ESA’s XMM-Newton as well as NASA’s Swift and RXTE satellites. They were able to make an accurate estimate of the strength of the external magnetic field by measuring how its rotation speed changes during an X-ray outburst. These outbursts are likely caused by fractures in the crust of the neutron star precipitated by the buildup of stress in the stronger magnetic field lying below the surface.

By modeling the evolution of the cooling of the neutron star and its crust, as well as the gradual decay of its magnetic field, the researchers estimated that SGR 0418 is about 550,000 years old. This makes SGR 0418 older than most other magnetars, and this extended lifetime has probably allowed the surface magnetic field strength to decline over time. Because the crust weakened and the interior magnetic field is relatively strong, outbursts could still occur.

The implications of this result for understanding supernova explosions and the number and evolution of magnetars is discussed in the press release.

SGR 0418 is located in the Milky Way galaxy at a distance of about 6,500 light years from Earth. These new results on SGR 0418 appear online and will be published in the June 10, 2013 issue of The Astrophysical Journal. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/CSIC-IEEC/N.Rea et al; Optical: Isaac Newton Group of Telescopes, La Palma/WHT; Infrared: NASA/JPL-Caltech

Composite image of 4C29.30, a galaxy located some 850 million light years from Earth

This composite image of a galaxy illustrates how the intense gravity of a supermassive black hole can be tapped to generate immense power. The image contains X-ray data from NASA’s Chandra X-ray Observatory (blue), optical light obtained with the Hubble Space Telescope (gold) and radio waves from the NSF’s Very Large Array (pink).

This multi-wavelength view shows 4C+29.30, a galaxy located some 850 million light years from Earth. The radio emission comes from two jets of particles that are speeding at millions of miles per hour away from a supermassive black hole at the center of the galaxy. The estimated mass of the black hole is about 100 million times the mass of our Sun. The ends of the jets show larger areas of radio emission located outside the galaxy.

The X-ray data show a different aspect of this galaxy, tracing the location of hot gas. The bright X-rays in the center of the image mark a pool of million-degree gas around the black hole. Some of this material may eventually be consumed by the black hole, and the magnetized, whirlpool of gas near the black hole could in turn, trigger more output to the radio jet.

Most of the low-energy X-rays from the vicinity of the black hole are absorbed by dust and gas, probably in the shape of a giant doughnut around the black hole. This doughnut, or torus blocks all the optical light produced near the black hole, so astronomers refer to this type of source as a hidden or buried black hole. The optical light seen in the image is from the stars in the galaxy.

The bright spots in X-ray and radio emission on the outer edges of the galaxy, near the ends of the jets, are caused by extremely high energy electrons following curved paths around magnetic field lines. They show where a jet generated by the black hole has plowed into clumps of material in the galaxy (mouse over the image for the location of these bright spots). Much of the energy of the jet goes into heating the gas in these clumps, and some of it goes into dragging cool gas along the direction of the jet. Both the heating and the dragging can limit the fuel supply for the supermassive black hole, leading to temporary starvation and stopping its growth. This feedback process is thought to cause the observed correlation between the mass of the supermassive black hole and the combined mass of the stars in the central region or bulge or a galaxy.

These results were reported in two different papers. The first, which concentrated on the effects of the jets on the galaxy, is available online and was published in the May 10, 2012 issue of The Astrophysical Journal. It is led by Aneta Siemiginowska from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, MA and the co-authors are Łukasz Stawarz, from the Institute of Space and Astronautical Science in Yoshinodai, Japan; Teddy Cheung from the National Academy of Sciences in Washington, DC; Thomas Aldcroft from CfA; Jill Bechtold from University of Arizona in Tucson, AZ; Douglas Burke from CfA; Daniel Evans from CfA; Joanna Holt from Leiden University in Leiden, The Netherlands; Marek Jamrozy from Jagiellonian University in Krakow, Poland; and Giulia Migliori from CfA. The second, which concentrated on the supermassive black hole, is available online and was published in the October 20, 2012 issue of The Astrophysical Journal. It is led by Malgorzata Sobolewska from CfA, and the co-authors are Aneta Siemiginowska, Giulia Migliori, Łukasz Stawarz, Marek Jamrozy, Daniel Evans, and Teddy Cheung.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/SAO/A. Siemiginowska et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA

A giant gas cloud, or halo, located in system NGC 6240

Scientists have used Chandra to make a detailed study of an enormous cloud of hot gas enveloping two large, colliding galaxies. This unusually large reservoir of gas contains as much mass as 10 billion Suns, spans about 300,000 light years, and radiates at a temperature of more than 7 million degrees.

This giant gas cloud, which scientists call a “halo,” is located in the system called NGC 6240. Astronomers have long known that NGC 6240 is the site of the merger of two large spiral galaxies similar in size to our own Milky Way. Each galaxy contains a supermassive black hole at its center. The black holes are spiraling toward one another, and may eventually merge to form a larger black hole.

Another consequence of the collision between the galaxies is that the gas contained in each individual galaxy has been violently stirred up. This caused a baby boom of new stars that has lasted for at least 200 million years. During this burst of stellar birth, some of the most massive stars raced through their evolution and exploded relatively quickly as supernovas.

The scientists involved with this study argue that this rush of supernova explosions dispersed relatively high amounts of important elements such as oxygen, neon, magnesium, and silicon into the hot gas of the newly combined galaxies. According to the researchers, the data suggest that this enriched gas has slowly expanded into and mixed with cooler gas that was already there.

During the extended baby boom, shorter bursts of star formation have occurred. For example, the most recent burst of star formation lasted for about five million years and occurred about 20 million years ago in Earth’s timeframe. However, the authors do not think that the hot gas was produced just by this shorter burst.

What does the future hold for observations of NGC 6240? Most likely the two spiral galaxies will form one young elliptical galaxy over the course of millions of years. It is unclear, however, how much of the hot gas can be retained by this newly formed galaxy, rather than lost to surrounding space. Regardless, the collision offers the opportunity to witness a relatively nearby version of an event that was common in the early Universe when galaxies were much closer together and merged more often.

In this new composite image of NGC 6240, the X-rays from Chandra that reveal the hot gas cloud are colored purple. These data have been combined with optical data from the Hubble Space Telescope, which shows long tidal tails from the merging galaxies, extending to the right and bottom of the image.

A paper describing these new results on NGC 6240 is available online and appeared in the March 10, 2013 issue of The Astrophysical Journal. The authors in this study were Emanuele Nardini (Harvard-Smithsonian Center for Astrophysics, or CfA, Cambridge, MA and currently at Keele University, UK), Junfeng Wang (CfA and currently at Northwestern University, Evanston, IL), Pepi Fabbiano (CfA), Martin Elvis (CfA), Silvia Pellegrini (University of Bologna, Italy), Guido Risalti (INAF-Osservatorio Astrofisico di Arcetri, Italy and CfA), Margarita Karovska (CfA), and Andreas Zezas (University of Crete, Greece and CfA).

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/SAO/E. Nardini et al; Optical: NASA/STScI

Supernova remnant SN 1006

This year, astronomers around the world have been celebrating the 50th anniversary of X-ray astronomy. Few objects better illustrate the progress of the field in the past half-century than the supernova remnant known as SN 1006.

When the object we now call SN 1006 first appeared on May 1, 1006 A.D., it was far brighter than Venus and visible during the daytime for weeks. Astronomers in China, Japan, Europe, and the Arab world all documented this spectacular sight. With the advent of the Space Age in the 1960s, scientists were able to launch instruments and detectors above Earth’s atmosphere to observe the universe in wavelengths that are blocked from the ground, including X-rays. SN 1006 was one of the faintest X-ray sources detected by the first generation of X-ray satellites.

A new image of SN 1006 from NASA’s Chandra X-ray Observatory reveals this supernova remnant in exquisite detail. By overlapping ten different pointings of Chandra’s field-of-view, astronomers have stitched together a cosmic tapestry of the debris field that was created when a white dwarf star exploded, sending its material hurtling into space. In this new Chandra image, low, medium, and higher-energy X-rays are colored red, green, and blue respectively.

The new Chandra image provides new insight into the nature of SN 1006, which is the remnant of a so-called Type Ia supernova. This class of supernova is caused when a white dwarf pulls too much mass from a companion star and explodes, or when two white dwarfs merge and explode. Understanding Type Ia supernovas is especially important because astronomers use observations of these explosions in distant galaxies as mileposts to mark the expansion of the universe.

The new SN 1006 image represents the most spatially detailed map yet of the material ejected during a Type Ia supernova. By examining the different elements in the debris field — such as silicon, oxygen, and magnesium — the researchers may be able to piece together how the star looked before it exploded and the order that the layers of the star were ejected, and constrain theoretical models for the explosion.

Scientists are also able to study just how fast specific knots of material are moving away from the original explosion. The fastest knots are moving outward at almost eleven million miles per hour, while those in other areas are moving at a more leisurely seven million miles per hour. SN 1006 is located about 7,000 light years from Earth. The new Chandra image of SN 1006 contains over eight days worth of observing time by the telescope. These results were presented at a meeting of High Energy Astrophysics Division of the American Astronomical Society in Monterey, CA.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: NASA/CXC/Middlebury College/F.Winklerch

Star formation in NGC 602, part of the wing region of the Small Magellanic Cloud, a dwarf galaxy

The Small Magellanic Cloud (SMC) is one of the Milky Way’s closest galactic neighbors. Even though it is a small, or so-called dwarf galaxy, the SMC is so bright that it is visible to the unaided eye from the Southern Hemisphere and near the equator. Many navigators, including Ferdinand Magellan who lends his name to the SMC, used it to help find their way across the oceans.

Modern astronomers are also interested in studying the SMC (and its cousin, the Large Magellanic Cloud), but for very different reasons. Because the SMC is so close and bright, it offers an opportunity to study phenomena that are difficult to examine in more distant galaxies.

New Chandra data of the SMC have provided one such discovery: the first detection of X-ray emission from young stars with masses similar to our Sun outside our Milky Way galaxy. The new Chandra observations of these low-mass stars were made of the region known as the “Wing” of the SMC. In this composite image of the Wing the Chandra data is shown in purple, optical data from the Hubble Space Telescope is shown in red, green and blue and infrared data from the Spitzer Space Telescope is shown in red.

Astronomers call all elements heavier than hydrogen and helium — that is, with more than two protons in the atom’s nucleus — “metals.” The Wing is a region known to have fewer metals compared to most areas within the Milky Way. There are also relatively lower amounts of gas, dust, and stars in the Wing compared to the Milky Way.

Taken together, these properties make the Wing an excellent location to study the life cycle of stars and the gas lying in between them. Not only are these conditions typical for dwarf irregular galaxies like the SMC, they also mimic ones that would have existed in the early Universe.

Most star formation near the tip of the Wing is occurring in a small region known as NGC 602, which contains a collection of at least three star clusters. One of them, NGC 602a, is similar in age, mass, and size to the famous Orion Nebula Cluster. Researchers have studied NGC 602a to see if young stars — that is, those only a few million years old — have different properties when they have low levels of metals, like the ones found in NGC 602a.

Using Chandra, astronomers discovered extended X-ray emission, from the two most densely populated regions in NGC 602a. The extended X-ray cloud likely comes from the population of young, low-mass stars in the cluster, which have previously been picked out by infrared and optical surveys, using Spitzer and Hubble respectively. This emission is not likely to be hot gas blown away by massive stars, because the low metal content of stars in NGC 602a implies that these stars should have weak winds. The failure to detect X-ray emission from the most massive star in NGC 602a supports this conclusion, because X-ray emission is an indicator of the strength of winds from massive stars. No individual low-mass stars are detected, but the overlapping emission from several thousand stars is bright enough to be observed.

The Chandra results imply that the young, metal-poor stars in NGC 602a produce X-rays in a manner similar to stars with much higher metal content found in the Orion cluster in our galaxy. The authors speculate that if the X-ray properties of young stars are similar in different environments, then other related properties — including the formation and evolution of disks where planets form — are also likely to be similar.

X-ray emission traces the magnetic activity of young stars and is related to how efficiently their magnetic dynamo operates. Magnetic dynamos generate magnetic fields in stars through a process involving the star’s speed of rotation, and convection, the rising and falling of hot gas in the star’s interior.

The combined X-ray, optical and infrared data also revealed, for the first time outside our Galaxy, objects representative of an even younger stage of evolution of a star. These so-called “young stellar objects” have ages of a few thousand years and are still embedded in the pillar of dust and gas from which stars form, as in the famous “Pillars of Creation” of the Eagle Nebula.

A paper describing these results was published online and in the March 1, 2013 issue of The Astrophysical Journal. The first author is Lidia Oskinova from the University of Potsdam in Germany and the co-authors are Wei Sun from Nanjing University, China; Chris Evans from the Royal Observatory Edinburgh, UK; Vincent Henault-Brunet from University of Edinburgh, UK; You-Hua Chu from the University of Illinois, Urbana, IL; John Gallagher III from the University of Wisconsin-Madison, Madison, WI; Martin Guerrero from the Instituto de Astrofísica de Andalucía, Spain; Robert Gruendl from the University of Illinois, Urbana, IL; Manuel Gudel from the University of Vienna, Austria; Sergey Silich from the Instituto Nacional de Astrofısica Optica y Electr´onica, Puebla, Mexico; Yang Chen from Nanjing University, China; Yael Naze from Universite de Liege, Liege, Belgium; Rainer Hainich from the University of Potsdam, Germany, and Jorge Reyes-Iturbide from the Universidade Estadual de Santa Cruz, Ilheus, Brazil.

Credits: X-ray: NASA/CXC/Univ.Potsdam/L.Oskinova et al; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech

Composite image of Kepler supernova remnant

This composite image shows Spitzer infrared emission in pink and Chandra X-ray emission from iron in blue. The infrared emission is very similar in shape and location to X-ray emission (not shown here) from material that was expelled by the giant star companion to the white dwarf before the latter exploded. This material forms a disk around the center of the explosion as shown in the labeled version. This composite figure also shows a remarkably large and puzzling concentration of iron on the left side of the center of the remnant but not the right. The authors speculate that the cause of this asymmetry might be the “shadow” in iron that was cast by the companion star, which blocked the ejection of material. Previously, theoretical work has suggested this shadowing is possible for Type Ia supernova remnants.

Credits: X-ray: NASA/CXC/NCSU/M.Burkey et al; Infrared: NASA/JPL-Caltech.

Kepler supernova remnant

This is the remnant of Kepler’s supernova, the famous explosion that was discovered by Johannes Kepler in 1604. The red, green and blue colors show low, intermediate and high energy X-rays observed with NASA’s Chandra X-ray Observatory, and the star field is from the Digitized Sky Survey.

As reported in our press release, a new study has used Chandra to identify what triggered this explosion. It had already been shown that the type of explosion was a so-called Type Ia supernova, the thermonuclear explosion of a white dwarf star. These supernovas are important cosmic distance markers for tracking the accelerated expansion of the Universe.

However, there is an ongoing controversy about Type Ia supernovas. Are they caused by a white dwarf pulling so much material from a companion star that it becomes unstable and explodes? Or do they result from the merger of two white dwarfs?

The new Chandra analysis shows that the Kepler supernova was triggered by an interaction between a white dwarf and a red giant star. The crucial evidence from Chandra was a disk-shaped structure near the center of the remnant. The researchers interpret this X-ray emission to be caused by the collision between supernova debris and disk-shaped material that the giant star expelled before the explosion. Another possibility was that the structure is just debris from the explosion.

The disk structure seen by Chandra in X-rays is very similar in both shape and location to one observed in the infrared by the Spitzer Space Telescope. This composite image shows Spitzer data in pink and Chandra data from iron emission in blue. The disk structure is identified with a label.

This composite figure also shows a remarkably large and puzzling concentration of iron on one side of the center of the remnant but not the other. The authors speculate that the cause of this asymmetry might be the “shadow” in iron that was cast by the companion star, which blocked the ejection of material. Previously, theoretical work has suggested this shadowing is possible for Type Ia supernova remnants.

The authors also produced a video showing a simulation of the supernova explosion as it interacts with material expelled by the giant star companion. It was assumed that the bulk of this material was expelled in a disk-like structure, with a gas density that is ten times higher at the equator, running from left to right, than at the poles. This simulation was performed in two dimensions and then projected into three dimensions to give an image that can be compared with observations. The good agreement with observations supports their interpretation of the data.

These results were published online and in the February 10th, 2013 issue of The Astrophysical Journal.

Credits: X-ray: NASA/CXC/NCSU/M.Burkey et al; Infrared: NASA/JPL-Caltech

Supernova remnant W49B

The highly distorted supernova remnant shown in this image may contain the most recent black hole formed in the Milky Way galaxy. The image combines X-rays from NASA’s Chandra X-ray Observatory in blue and green, radio data from the NSF’s Very Large Array in pink, and infrared data from Caltech’s Palomar Observatory in yellow.

The remnant, called W49B, is about a thousand years old, as seen from Earth, and is at a distance about 26,000 light years away.

The supernova explosions that destroy massive stars are generally symmetrical, with the stellar material blasting away more or less evenly in all directions. However, in the W49B supernova, material near the poles of the doomed rotating star was ejected at a much higher speed than material emanating from its equator. Jets shooting away from the star’s poles mainly shaped the supernova explosion and its aftermath.

By tracing the distribution and amounts of different elements in the stellar debris field, researchers were able to compare the Chandra data to theoretical models of how a star explodes. For example, they found iron in only half of the remnant while other elements such as sulfur and silicon were spread throughout. This matches predictions for an asymmetric explosion. Also, W49B is much more barrel-shaped than most other remnants in X-rays and several other wavelengths, pointing to an unusual demise for this star.

The authors also examined what sort of compact object the supernova explosion left behind. Most of the time, massive stars that collapse into supernovas leave a dense spinning core called a neutron star. Astronomers can often detect these neutron stars through their X-ray or radio pulses, although sometimes an X-ray source is seen without pulsations. A careful search of the Chandra data revealed no evidence for a neutron star, implying an even more exotic object might have formed in the explosion, that is, a black hole.

This may be the youngest black hole formed in the Milky Way galaxy, with an age of only about a thousand years, as viewed from Earth (i.e., not including the light travel time). A well-known example of a supernova remnant in our galaxy that likely contains a black hole is SS433. This remnant is thought to have an age between 17,000 and 21,000 years, as seen from Earth, making it much older than W49B.

The new results on W49B, which were based on about two-and-a-half days of Chandra observing time, appear in a paper in the Feb. 10, 2013 issue of the Astrophysical Journal. The authors of the paper are Laura Lopez, from the Massachusetts Institute of Technology (MIT), Enrico Ramirez-Ruiz from the University of California at Santa Cruz, Daniel Castro, also of MIT, and Sarah Pearson from the University of Copenhagen in Denmark.

Credits: X-ray: NASA/CXC/MIT/L.Lopez et al; Infrared: Palomar; Radio: NSF/NRAO/VLA

Composite image of superbubble DEM L50

This composite image shows the superbubble DEM L50 (a.k.a. N186) located in the Large Magellanic Cloud about 160,000 light years from Earth. Superbubbles are found in regions where massive stars have formed in the last few million years. The massive stars produce intense radiation, expel matter at high speeds, and race through their evolution to explode as supernovas. The winds and supernova shock waves carve out huge cavities called superbubbles in the surrounding gas.

X-rays from NASA’s Chandra X-ray Observatory are shown in pink and optical data from the Magellanic Cloud Emission Line Survey (MCELS) are colored in red, green and blue. The MCELS data were obtained with the University of Michigan’s 0.9-meter Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory (CTIO). The shape of DEM L50 is approximately an ellipse, with a supernova remnant named SNR N186 D located on its northern edge.

Like another superbubble in the LMC, N44, DEM L50 gives off about 20 times more X-rays than expected from standard models for the evolution of superbubbles. A Chandra study published in 2011 showed that there are two extra sources of the bright X-ray emission: supernova shock waves striking the walls of the cavities, and hot material evaporating from the cavity walls.

The Chandra study of DEM L50 was published in the Astrophysical Journal in 2011 and was led by Anne Jaskot from the University of Michigan in Ann Arbor. The Chandra study of DEM L50 was led by Anne Jaskot from the University of Michigan in Ann Arbor. The co-authors were Dave Strickland from Johns Hopkins University in Baltimore, MD, Sally Oey from University of Michigan, You-Hua Chu from University of Illinois and Guillermo Garcia-Segura from Instituto de Astronomia-UNAM in Ensenada, Mexico.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/Univ of Michigan/A.E.Jaskot, Optical: NOAO/CTIO/MCELS

The Vela pulsar, a neutron star that was formed when a massive star collapsed.

This movie from NASA’s Chandra X-ray Observatory shows a fast moving jet of particles produced by a rapidly rotating neutron star, and may provide new insight into the nature of some of the densest matter in the universe.

The star of this movie is the Vela pulsar, a neutron star that was formed when a massive star collapsed. The Vela pulsar is about 1,000 light years from Earth, spansis about 12 miles in diameter, and makes over 11 complete rotations every second, faster than a helicopter rotor. As the pulsar whips around, it spews out a jet of charged particles that race out along the pulsar’s rotation axis at about 70% of the speed of light. In this still image from the movie, the location of the pulsar and the 0.7-light-year-long jet are labeled.

The Chandra data shown in the movie, containing eight images obtained between June and September 2010, suggest that the pulsar may be slowly wobbling, or precessing, as it spins. The shape and the motion of the Vela jet look strikingly like a rotating helix, a shape that is naturally explained by precession, as shown in this animation [link to mathematica animation from Oleg K]. If the evidence for precession of the Vela pulsar is confirmed, it would be the first time that a jet from a neutron star has been found to be wobbling, or precessing, in this way.

One possible cause of precession for a spinning neutron star is that it has become slightly distorted and is no longer a perfect sphere. This distortion might be caused by the combined action of the fast rotation and “glitches”, sudden increases of the pulsar’s rotational speed due to the interaction of the superfluid core of the neutron star with its crust.

A paper describing these results will be published in The Astrophysical Journal on January 10, 2013.

This is the second Chandra movie of the Vela pulsar, with the original having been released in 2003. The first Vela movie contained shorter, unevenly spaced observations so that the changes in the jet were less pronounced and the authors did not argue that precession was occurring. However, based on the same data, Avinash Deshpande of Arecibo Observatory in Puerto Rico and the Raman Research Institute in Bangalore, India, and the late Venkatraman Radhakrishnan, argued in a 2007 paper that the Vela pulsar might be precessing.

The Earth also precesses as it spins, with a period of about 26,000 years. In the future Polaris will no longer be the “north star” and other stars will take its place. The period of the Vela precession is much shorter and is estimated to be about 120 days.

The supernova that formed the Vela pulsar exploded over 10,000 years ago. This optical image from the Anglo-Australian Observatory’s UK Schmidt telescope shows the enormous apparent size of the supernova remnant formed by the explosion. The full size of the remnant is about eight degrees across, or about 16 times the angular size of the moon. The square near the center shows the Chandra image with a larger field-of-view than used for the movie, with the Vela pulsar in the middle.

Credits: X-ray: NASA/CXC/Univ of Toronto/M.Durant et al; Optical: DSS/Davide De Martin

A large elliptical galaxy at the center of the galaxy cluster PKS 0745 19

The black hole at the center of this galaxy is part of a survey of 18 of the biggest black holes in the universe. This large elliptical galaxy is in the center of the galaxy cluster PKS 0745-19, which is located about 1.3 billion light years from Earth.. X-ray data from NASA’s Chandra X-ray Observatory are shown in purple and optical data from the Hubble Space Telescope are in yellow.

The researchers found that these black holes may be about ten times more massive than previously thought, with at least ten of them weighing between 10 and 40 billion times the mass of the sun.

All of the potential “ultramassive” black holes found in this study lie in galaxies at the centers of galaxy clusters containing huge amounts of hot gas. This hot gas produces the diffuse X-ray emission seen in the image. Outbursts powered by the central black holes create cavities in the gas preventing it from cooling and forming enormous numbers of stars. To generate the outbursts, the black holes must swallow large amounts of mass. Because the largest black holes can swallow the most mass and power the biggest outbursts, ultramassive black holes had already been predicted to exist to explain some of the most powerful outbursts seen.

In addition to the X-rays from Chandra, the new study also uses radio data from the NSF’s Karl G. Jansky Very Large Array (JVLA) and the Australia Telescope Compact Array (ATCA) and infrared data from the 2 Micron All-Sky Survey (2MASS). These results were published [link to press release] in the July 2012 issue of The Monthly Notices of the Royal Astronomical Society.

Credits: X-ray: NASA/CXC/Stanford/Hlavacek-Larrondo, J. et al; Optical: NASA/STScI

Spiral galaxy NGC 3627

The spiral galaxy NGC 3627 is located about 30 million light years from Earth. This composite image includes X-ray data from NASA’s Chandra X-ray Observatory (blue), infrared data from the Spitzer Space Telescope (red), and optical data from the Hubble Space Telescope and the Very Large Telescope (yellow). The inset shows the central region, which contains a bright X-ray source that is likely powered by material falling onto a supermassive black hole.

A search using archival data from previous Chandra observations of a sample of 62 nearby galaxies has shown that 37 of the galaxies, including NGC 3627, contain X-ray sources in their centers. Most of these sources are likely powered by central supermassive black holes. The survey, which also used data from the Spitzer Infrared Nearby Galaxy Survey, found that seven of the 37 sources are new supermassive black hole candidates.

Confirming previous Chandra results, this study finds the fraction of galaxies found to be hosting supermassive black holes is much higher than found with optical searches. This shows the ability of X-ray observations to find black holes in galaxies where relatively low-level black hole activity has either been hidden by obscuring material or washed out by the bright optical light of the galaxy.

The combined X-ray and infrared data suggest that the nuclear activity in a galaxy is not necessarily related to the amount of star-formation in the galaxy, contrary to some early claims. In contrast, these new results suggest that the mass of the supermassive black hole and the rate at which the black hole accretes matter are both greater for galaxies with greater total masses.

A paper describing these results was published in the April 10, 2011 issue of The Astrophysical Journal. The authors are Catherine Grier and Smita Mathur of The Ohio State University in Columbus, OH; Himel GHosh of CNRS/CEA-Saclay in Guf-sur-Yvette, France and Laura Ferrarese from Herzberg Institute of Astrophysics in Victoria, Canada.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: NASA/CXC/Ohio State Univ./C.Grier et al.; Optical: NASA/STScI, ESO/WFI; Infrared: NASA/JPL-Caltech

Composite image of ring galaxy NGC 922

n this holiday season of home cooking and carefully-honed recipes, some astronomers are asking: what is the best mix of ingredients for stars to make the largest number of plump black holes?

They are tackling this problem by studying the number of black holes in galaxies with different compositions. One of these galaxies, the ring galaxy NGC 922, is seen in this composite image containing X-rays from NASA’s Chandra X-ray Observatory (red) and optical data from the Hubble Space Telescope (pink, yellow and blue).

NGC 922 was formed by the collision between two galaxies – one seen in this image and another located outside the field of view. This collision triggered the formation of new stars in the shape of a ring. Some of these were massive stars that evolved and collapsed to form black holes.

Most of the bright X-ray sources in Chandra’s image of NGC 922 are black holes pulling material in from the winds of massive companion stars. Seven of these are what astronomers classify as “ultraluminous X-ray sources” (ULXs). These are thought to contain stellar-mass black holes that are at least ten times more massive than the sun, which places them in the upper range for this class of black hole. They are a different class from the supermassive black holes found at the centers of galaxies, which are millions to billions of times the mass of the sun.

Theoretical work suggests that the most massive stellar-mass black holes should form in environments containing a relatively small fraction of elements heavier than hydrogen and helium, called “metals” by astronomers. In massive stars, the processes that drive matter away from the stars in stellar winds work less efficiently if the fraction of metals is smaller. Thus, stars with fewer of these metals among their ingredients should lose less of their mass through winds as they evolve. A consequence of this reduced mass loss is that a larger proportion of massive stars will collapse to form black holes when their nuclear fuel is exhausted. This theory appeared to be supported by the detection of a large number (12) of ULXs in the Cartwheel galaxy, where stars typically contain only about 30% of the metals found in the sun.

To test this theory, scientists studied NGC 922, which contains about the same fraction of metals as the sun, meaning that this galaxy is about three times richer in metals than the Cartwheel galaxy. Perhaps surprisingly, the number of ULXs found in NGC 922 is comparable to the number seen in the Cartwheel galaxy. Rather, the ULX tally appears to depend only on the rate at which stars are forming in the two galaxies, not on the fraction of metals they contain.

One explanation for these results is that the theory predicting the most massive stellar-mass black holes should form in metal poor conditions is incorrect. Another explanation is that the metal fraction in the Cartwheel galaxy is not low enough to have a clear effect on the production of unusually massive stellar-mass black holes, and therefore will not cause an enhancement in the number of ULXs. Recent models incorporating the evolution of stars suggest that a clear enhancement in the number of ULXs might only be seen when the metal fraction falls below about 15% of the Sun’s value. Astronomers are investigating this possibility by observing galaxies with extremely low metal fractions using Chandra. The number of ULXs is being compared with the number found in galaxies with higher metal content. The results of this work will be published in a future paper.

A paper describing the results for NGC 922 was published in the March 10, 2012 issue of the Astrophysical Journal. The authors were Andrea Prestwich and Jose Luis Galache of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, MA; Tim Linden from University of Santa Cruz in Santa Cruz, CA; Vicky Kalogera from Northwestern University in Evanston, IL; Andreas Zezas from CfA and University of Crete in Crete, Greece; Tim Roberts from University of Durham in Durham, UK; Roy Kilgard from Wesleyan University in Middletown, CT; Anna Wolter and Ginevra Trinchieri from INAF in Milano, Italy. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/SAO/A. Prestwich et al; Optical: NASA/STScI

IRIS to Take Precise Look at Sun’s Energy


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IRIS (Interface Region Imaging Spectrograph )to Take Precise Look at Sun’s Energy

http://www.nasa.gov/mission_pages/iris/launch/IRIS-prelaunchfeature.html

By Steven Siceloff,
NASA’s Kennedy Space Center

The IRIS spacecraft on Pegasus rocket.

IRIS to Take Precise Look at Sun’s Energy

NASA’s IRIS spacecraft will use an ultraviolet telescope to look at a small area of the sun to answer detailed questions about the way the sun’

Mission Statement

Understanding the interface between the photosphere and corona remains a fundamental challenge in solar and heliospheric science. The Interface Region Imaging Spectrograph (IRIS) mission opens a window of discovery into this crucial region by tracing the flow of energy and plasma through the chromosphere and transition region into the corona using spectrometry and imaging. IRIS is designed to provide significant new information to increase our understanding of energy transport into the corona and solar wind and provide an archetype for all stellar atmospheres. The unique instrument capabilities, coupled with state of the art 3-D modeling, will fill a large gap in our knowledge of this dynamic region of the solar atmosphere. The mission will extend the scientific output of existing heliophysics spacecraft that follow the effects of energy release processes from the sun to Earth.

Researchers hope NASA’s latest solar observatory will answer a fundamental question of how the sun creates such intense energy.

Scheduled to launch June 26, the IRIS spacecraft will point a telescope at the interface region of the sun that lies between the surface and the million degree outer atmosphere called the corona. It will improve our understanding of how energy moves from the sun’s surface to the glowing corona, heating up from 6,000 degrees to millions of degrees.

The IRIS mission, short for Interface Region Imaging Spectrograph, calls for the 7-foot-long spacecraft to point its ultraviolet telescope at the sun to discern features as small as 150 miles across. It will look at about 1 percent of the sun’s surface.

“IRIS will show the solar chromosphere in more detail than has ever been observed before,” said Adrian Daw, deputy project scientist. “My opinion is that we are bound to see something we didn’t expect to see.”

IRIS is a NASA Small Explorer that will complement the Solar Dynamics Observatory and Hinode missions to explore how the solar atmosphere works and impacts Earth. SDO and Hinode will monitor the solar surface and outer atmosphere, with IRIS watching the region in between.

“IRIS almost acts as a microscope to SDO’s telescope,” said Jim Hall, mission manager for IRIS. “It’s going to look in closely and it’s going to look at that specific region to see how the changes in matter and energy occur in this region. It’s going to collectively bring us a more complete view of the sun.” IRIS improves our understanding of the interface region where most of the sun’s ultraviolet emission is generated that impacts the near Earth space environment and Earth’s climate. Solar activity such as coronal mass ejections and solar flares, also are of great interest to spacecraft designers who have to figure out ways to protect instruments and electronics from them.

“We’re always looking for the answers to why and everything starts at the root with the sun,” Hall said.

Screen capture showing an active sun from IRIS new explorer video.

At the end of June 2013, NASA will launch its newest set of instruments to watch the sun: the Interface Region Imaging Spectrograph, or IRIS.

IRIS will ride into Earth orbit on an Orbital Sciences Pegasus XL rocket. The Pegasus is famous as the only winged launcher in NASA’s inventory. Though small compared to the gigantic boosters that send heavy satellites into orbit and probes to distant worlds, the Pegasus’ size and flexibility has allowed numerous missions to be launched that would have been too small for larger rockets.

“Pegasus has been a tremendously successful launch vehicle for NASA,” said Tim Dunn, launch director for IRIS. “We have launched 18 successful missions on Pegasus. The team is very dynamic, very flexible. They’re able to accomplish a tremendous amount in a very short time.”

The Pegasus and its IRIS payload will be carried to about 39,000 feet under a modified L-1011 airliner taking off from Vandenberg Air Force Base in California. Over the Pacific Ocean off the California coast, the plane will drop the Pegasus to begin the launch.

The Pegasus will ignite its solid-fueled first stage five seconds into its fall and arch skyward with the main wing giving it lift and the three fins in the back steering it through the thick layers of Earth’s lower atmosphere.

The rocket will burn its load of fuel in 73 seconds and fall away. The second stage, which has no wings, will ignite 94 seconds into flight and push IRIS higher and faster into space. The third stage will take over after that, delivering IRIS into its orbit about 10 minutes after launch.

This is the last one scheduled for the Pegasus rocket because there are not any small spacecraft missions that fit the Pegasus niche.

The launch is taking place from the West Coast because IRIS will go into a roughly polar orbit, meaning it will cross over the north and south pole regions of Earth on each pass around the planet.
Hinode views the lower regions of the sun’s atmosphere, the interface region, which a new mission called the Interface Region Imaging Spectrograph will study in exquisite detail.

Understanding how energy travels through the lowest layers of the sun’s atmosphere is the goal of NASA’s Interface Region Imaging Spectrograph .

“Eight months out of the year, we are freely viewing the sun in that orbit,” Hall said.

Once IRIS is in space with its solar panels unfolded to provide electricity and the telescope flipped open, scientists expect to see intriguing data pretty quickly.

“I think the biggest surprise will come once the mission is launched and it starts to observe the sun,” Daw said. “We know to some extent what we hope to learn, what specific science questions we are going to answer, but there’s always that element of surprise.”