Posted on by Tammy Plotner

Martian “Rust” Could Possibly Point To Past Water

Sojourner rover taking its Alpha Proton X-ray Spectrometer measurement. Credit: NASA

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It’s called a carbonate and it’s a mineral that’s common to water-logged formations… be it here on Earth, or on Mars. Until now only a few carbonate deposits have been found on Mars, but scientists are beginning to suspect it has been hiding all along under a thin layer of iron oxide. Because rust never sleeps…

“The plausibility of life on Mars depends on whether liquid water dotted its landscape for thousands or millions of years,” said Janice Bishop, a planetary scientist at NASA’s Ames Research Center at the SETI Institute at Moffett Field, California. “It’s possible that an important clue, the presence of carbonates, has largely escaped the notice of investigators trying to learn if liquid water once pooled on the Red Planet.”

How did they come to this conclusion? By studying similar conditions on rocks found in the Mojave Desert. Because the arid conditions are similar to the Martian environment, investigators can assume carbonates are hiding behind a veneer of rust – keeping them from view. This new evidence came to light earlier this year when Bishop and Chris McKay – a planetary scientist at Ames – collected samples from an area called Little Red Hill.

“When we examined the carbonate rocks in the lab, it became evident that an iron oxide skin may be hindering the search for clues to the Red Planet’s hydrological history,” McKay said. “We found that the varnish both altered and partially masked the spectral signature of the carbonates.”

But rust wasn’t all they found… there was also a signature of dehydration-resistant blue-green algae. This biologic implication means the iron oxide coating may have also extended the time period that Mars could have supported such a life form. “The organisms in the Mojave Desert are protected from deadly ultraviolet light by the iron oxide coating,” McKay said. “This survival mechanism might have played a role if Mars once had life on the surface.”

Why are these carbonate findings important? Every mineral has a unique absorption bands, spectral frequencies and vibrational modes. Using this information, planetary scientists can identify composition. Because of the layer of rust, many carbonate deposits may have been overlooked because their spectral signatures were masked.

“To better determine the extent of carbonate deposits on Mars, and by inference the ancient abundance of liquid water, we need to investigate the spectral properties of carbonates mixed with other minerals,” Bishop said.

Like all rust, the deposits were so overwhelming that NASA’s Mars Exploration Rovers, Spirit and Opportunity, used a motorized grinding tool to “clean” samples before spectral examination. With NASA’s newest and most capable rover, the Mars Science Laboratory “Curiosity” mission nearing its launch date, we may be able to take another, closer look at possible life on Mars.

Because there’s more to the picture than meets the eye…

Original Stoary Source: JPL/NASA News Release.

Posted on by Nancy Atkinson

The Question of Life on Mars Still Intrigues Us


QUEST on KQED Public Media.

Is there — or was there ever — life on Mars? And will we ever definitively find out? After multiple unmanned missions to Mars, we still can’t answer those questions, but the possibility of life on the Red Planet has intrigued us for decades and our interest in Mars still runs high. Here’s a video produced by the PBS affiliate in San Francisco, California, KQED and their science and environment series QUEST. It looks at our past fascination of Mars and how NASA scientists are hoping the Mars Science Lab rover will help them solve the mysteries of Mars.

Posted on by Nancy Atkinson

Stunning Noctilucent Clouds Shine Brightly in the UK

Panoramic view of Noctulucent Clouds from Kendal Castle in the UK. Credit: Stu Atkinson

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Mysterious “night shining” or Noctilucent Clouds are beautiful to behold, and here are some gorgeous examples what skywatchers in the UK have been experiencing. Stu Atkinson took this stunning panoramic view from Kendal Castle. (Click image for access to a larger version). NLCs are usually seen during the summertime, appearing at sunset. They are thin, wavy ice clouds that form at very high altitudes and reflect sunlight long after the Sun has dropped below the horizon. Scientists don’t know exactly why they form, and they seem to be appearing more and more in recent times.

See more below.

Science writer Will Gater also had a great view of NLCs this morning. Click the image to see his animation, or see more of his images and animations at his website post.

NLCs seen over the UK on July 1, 2011. Click to see animation. Credit: Will Gater
Another view of Noctilucent Clouds from Kendal Castle in the UK on July 1, 2011. Credit: Stu Atkinson

See more from Stu Atkinson at his Cumbrian Sky website.

Posted on by Vanessa Janek

Ancient Galaxies Fed On Gas, Not Collisions

The Sombrero Galaxy. Credit: ESO/P. Barthe

[/caption]The traditional picture of galaxy growth is not pretty. In fact, it’s a kind of cosmic cannibalism: two galaxies are caught in ominous tango, eventually melding together in a fiery collision, thus spurring on an intense but short-lived bout of star formation. Now, new research suggests that most galaxies in the early Universe increased their stellar populations in a considerably less violent way, simply by burning through their own gas over long periods of time.

The research was conducted by a group of astronomers at NASA’s Spitzer Science Center in Pasadena, California. The team used the Spitzer Space Telescope to peer at 70 distant galaxies that flourished when the Universe was only 1-2 billion years old. The spectra of 70% of these galaxies showed an abundance of H alpha, an excited form of hydrogen gas that is prevalent in busy star-forming regions. Today, only one out of every thousand galaxies carries such an abundance of H alpha; in fact, the team estimates that star formation in the early Universe outpaced that of today by a factor of 100!

This split view shows how a normal spiral galaxy around our local universe (left) might have looked back in the distant universe, when astronomers think galaxies would have been filled with larger populations of hot, bright stars (right). Image credit: NASA/JPL-Caltech/STScI

Not only did these early galaxies crank out stars much faster than their modern-day counterparts, but they created much larger stars as well. By grazing on their own stores of gas, galaxies from this epoch routinely formed stars up to 100 solar masses in size.

These impressive bouts of star formation occurred over the course of hundreds of millions of years. The extremely long time scales involved suggest that while they probably played a minor role, galaxy mergers were not the main precursor to star formation in the Universe’s younger years. “This type of galactic cannibalism was rare,” said Ranga-Ram Chary, a member of the team. “Instead, we are seeing evidence for a mechanism of galaxy growth in which a typical galaxy fed itself through a steady stream of gas, making stars at a much faster rate than previously thought.” Even on cosmic scales, it would seem that slow and steady really does win the race.

Source: JPL

Posted on by Vanessa Janek

Most Distant Quasar Opens Window Into Early Universe

Quasar
Quasar

[/caption]Astronomers have uncovered yet another clue in their quest to understand the Universe’s early life: the most distant quasar ever observed. At a redshift of 7.1, it is a relic from when the cosmos was just 770 million years old – just 5% of its age today.

Quasars are extremely old, outrageously luminous balls of radiation that were prevalent in the early Universe. Each is thought to have been fueled at its core by an incredibly powerful supermassive black hole. The most recent discovery (which carries the romantic name ULAS J1120+0641) is noteworthy for a couple of reasons. First of all, its supermassive black hole weighs approximately two billion solar masses – an impressive feat of gravity so soon after the Big Bang. It is also incredibly bright, given its great distance. “Objects that lie at such large distance are almost impossible to find in visible-light surveys because their light is stretched by the expansion of the universe,” said Dr. Simon Dye of the University of Nottingham, a member of the team that discovered the object. “This means that by the time their light gets to Earth, most of it ends up in the infrared part of the electromagnetic spectrum.” Due to these effects, only about 100 visible quasars exist in the sky at redshifts higher than 7.

Up until recently, the most distant quasar observed was at a redshift of 6.4; but thanks to this discovery, astronomers can probe 100 million years further into the history of the Universe than ever before. Careful study of ULAS J1120+0641 and its properties will enable scientists to learn more about galaxy formation and supermassive black hole growth in early epochs. The research was published in the June 30 issue of Nature.

For further reading, see related paper by Chris Willot, Monster in the Early Universe

Source: EurekAlert

Posted on by Jason Major

The Final Countdown: Fueling the Anticipation

The world will be watching - and tweeting! – when Atlantis launches on July 8

An update on my NASA Tweetup adventure…

The world will be watching - and tweeting! – when Atlantis launches on July 8
The launch of the space shuttle Atlantis is just a week away, and with it the NASA Tweetup event of a lifetime. (Well, my lifetime anyway!) But it’s not just me who’s been having visions of shuttle plumes dancing in his head… there’s 149 other space tweeps (yes, that’s what we call ourselves) who are eagerly counting the days, hours and minutes until then.

Here’s what some of them are saying…

“Wicked excited! (says the Boston gal – who yes, now lives in the Midwest!)” – Leslie Berg

“I’m so excited, and I just can’t hide it….” – David Parmet

“This has been a dream of mine since the first launch. I was so sad when I was unable to attend STS-134 with the delays and so excited when I found out that I could at least see the last launch paid to change my plane ticket to NYC for summer.” Dvora Geller

“It’s an honor to be chosen by NASA to be a part of the last flight in shuttle history.” – Heather Smith

“NASA has continued to fill the history books with their profound and inspirational achievements. I can’t believe I’ll witness another significant page being written for that book, in person, up close, on July 8th!! Bring it!!” – Justin Boddey

With people attending the Tweetup from not only all over the US but also all around the world, this is an awesome representation of the international attention that the final launch is getting.

Also, after some scouting about for the right contact person (thanks Susan!) I managed to get in touch with the metro editor at the Dallas Morning News and he assigned a reporter to cover my story. I had a phone interview this afternoon with her, and the story should be published next Tuesday! In addition they want to feature my Tweets on the news site live from the launch…I sure hope the 3G signal coverage isn’t overwhelmed!

Anyway by this time next week I and 149 others from around the world will be preparing for a very exciting morning… it’s going to be crazy, I’m sure, but totally worth it!

Stay tuned….

“I spend several moments a day suppressing the urge to freak right out over the fact that I’m going to be as close to going into space as I’ve ever been. There’s also a 9 year old in my head screaming SPACE SHUTTLE! all the time. It’s really distracting. I feel so lucky.” – Nicole KT Winchester

“Since the day I found out I was selected to attend the Tweetup, it’s been on my mind every minute of every day. I’m basically trying not to die before July 7th.” – Andres Almeida

“I can pretty much guarantee my reaction to seeing a space shuttle live, in person, will be, ‘Whoah.’ Followed shortly by, ‘That’s pretty.'” – Kara DeFrias

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Jason Major is a graphic designer, photo enthusiast and space blogger. Visit his website Lights in the Dark and follow him on Twitter @JPMajor or on Facebook for the most up-to-date astronomy awesomeness!

Posted on by Tammy Plotner

Neptune: Rocking The Dreidel

In this image, the colors and contrasts were modified to emphasize the planet’s atmospheric features. The winds in Neptune’s atmosphere can reach the speed of sound or more. Neptune’s Great Dark Spot stands out as the most prominent feature on the left. Several features, including the fainter Dark Spot 2 and the South Polar Feature, are locked to the planet’s rotation, which allowed Karkoschka to precisely determine how long a day lasts on Neptune. (Image: Erich Karkoschka)

When it come to making your head spin, Jupiter revolves on its axis in less than 10 hours. Up until now, it was the only gas planet in our solar system that had an accurate spin measurement. But grab your top and cut it loose, because University of Arizona planetary scientist Erich Karkoschka has clocked Neptune cruising around at a cool 15 hours, 57 minutes and 59 seconds.

“The rotational period of a planet is one of its fundamental properties,” said Karkoschka, a senior staff scientist at the UA’s Lunar and Planetary Laboratory. “Neptune has two features observable with the Hubble Space Telescope that seem to track the interior rotation of the planet. Nothing similar has been seen before on any of the four giant planets.”

Like spinning gelatin, the gas giants – Jupiter, Saturn, Uranus and Neptune – don’t behave in an easy to study manner. By nature they deform as they rotate, making accurate estimates difficult to pin down.

“If you looked at Earth from space, you’d see mountains and other features on the ground rotating with great regularity, but if you looked at the clouds, they wouldn’t because the winds change all the time,” Karkoschka explained. “If you look at the giant planets, you don’t see a surface, just a thick cloudy atmosphere.”

Of course, 350 years ago Giovanni Cassini was able to estimate Jupiter’s rotation by observing the Great Red Spot – an atmospheric condition. Neptune has observable atmospheric conditions, too… But they’re just a bit more transitory. “On Neptune, all you see is moving clouds and features in the planet’s atmosphere. Some move faster, some move slower, some accelerate, but you really don’t know what the rotational period is, if there even is some solid inner core that is rotating.”

Roughly 60 years ago astronomers discovered Jupiter gave out radio signals. These signals originated from its magnetic field generated by the spinning inner core. Unfortunately signals of this type from the outer planets were simply lost in space before they could be detected from here on Earth. “The only way to measure radio waves is to send spacecraft to those planets,” Karkoschka said. “When Voyager 1 and 2 flew past Saturn, they found radio signals and clocked them at exactly 10.66 hours, and they found radio signals for Uranus and Neptune as well. So based on those radio signals, we thought we knew the rotation periods of those planets.”

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Using the data from the Voyager probes, Karkoschka went to work studying rotation periods and combined it with available images of Neptune from the Hubble Space Telescope archive. Like Cassini’s work, he carefully studied atmospheric features in hundreds upon hundreds of photographs taken over a time sequence… a period of 20 years. He realized an observer watching the massive planet turn from a fixed spot in space would see these features appear exactly every 15.9663 hours, with less than a few seconds of variation. This led him to surmise a hidden interior feature on Neptune drives the mechanism that creates the atmospheric signature.

“So I dug up the images of Neptune that Voyager took in 1989, which have better resolution than the Hubble images, to see whether I could find anything else in the vicinity of those two features. I discovered six more features that rotate with the same speed, but they were too faint to be visible with the Hubble Space Telescope, and visible to Voyager only for a few months, so we wouldn’t know if the rotational period was accurate to the six digits. But they were really connected. So now we have eight features that are locked together on one planet, and that is really exciting.”

Original Story Source: University of Arizona News.

Posted on by Tammy Plotner

Eccentric Binary Creates Dual Gamma-Ray Flares

This diagram, which illustrates the view from Earth, shows the binary's anatomy as well as key events in the pulsar's recent close approach. Credit: NASA/Goddard Space Flight Center/Francis Reddy

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It’s a gamma-ray flare – the most extreme form of light so far known. So, what could top it? Try a pair of gamma-ray flares. Way off in the southern constellation of Crux, an extreme team of stars gave a real show to NASA’s Fermi Gamma-ray Space Telescope. In December 2010, they blew past each other at about the distance Venus orbits our Sun. Why was this encounter so unique? Because one member was hot and blue/white… and the other a pulsar.

“Even though we were waiting for this event, it still surprised us,” said Aous Abdo, a Research Assistant Professor at George Mason University in Fairfax, Va., and a leader of the research team.

Astronomers were aware that PSR B1259-63 and LS 2883 made a close pass to each other about every 3 to 4 years and were eagerly anticipating the action. Residing at about 8,000 light years away, the signature signal from PSR B1259-63 was discovered in 1989 by the Parkes radio telescope in Australia. It is suspected to be quite small – about the size of Washington, DC and weighs about twice as much as Sol. What’s cool is it rotates at a dizzying 21 times per second… shooting of a powerful beam of electromagnetic energy that sweeps around like a search light. Next door the blue/white companion star lay embedded in gas, measuring in about 9 times larger size and weighing in at about 24 solar masses. Of these “odd couples” only four are known to produce gamma-rays and only this particular system is known to contain a pulsar… one that punches through the gas disk both coming and going during orbit.

“During these disk passages, energetic particles emitted by the pulsar can interact with the disk, and this can lead to processes that accelerate particles and produce radiation at different energies,” said study co-author Simon Johnston of the Australia Telescope National Facility in Epping, New South Wales. “The frustrating thing for astronomers is that the pulsar follows such an eccentric orbit that these events only happen every 3.4 years.”

On December 15, 2010, all “eyes” and “ears” were turned the system’s way in anticipation of the dual gamma-ray burst. The observatories included Fermi and NASA’s Swift spacecraft; the European space telescopes XMM-Newton and INTEGRAL; the Japan-U.S. Suzaku satellite; the Australia Telescope Compact Array; optical and infrared telescopes in Chile and South Africa; and the High Energy Stereoscopic System (H.E.S.S.), a ground-based observatory in Namibia that can detect gamma rays with energies of trillions of electron volts, beyond Fermi’s range.

“When you know you have a chance of observing this system only once every few years, you try to arrange for as much coverage as you can,” said Abdo, the principal investigator of the NASA-funded international campaign. “Understanding this system, where we know the nature of the compact object, may help us understand the nature of the compact objects in other, similar systems”.

While the EGRET telescope aboard NASA’s Compton Gamma-Ray Observatory had been observing this rare pair since the 1990s, no gamma-ray emission in the billion-electron-volt (GeV) energy range had ever been recorded. But, as the time of passage approached, the Large Area Telescope (LAT) aboard Fermi began to pick up faint gamma-ray emission. “During the first disk passage, which lasted from mid-November to mid-December, the LAT recorded faint yet detectable emission from the binary. We assumed that the second passage would be similar, but in mid-January 2011, as the pulsar began its second passage through the disk, we started seeing surprising flares that were many times stronger than those we saw before,” Abdo said.

To make this strange scenario even more unusual, radio and x-ray readings were nominal as the gamma-rays flared. “The most intense days of the flare were Jan. 20 and 21 and Feb. 2, 2011,” said Abdo. “What really surprised us is that on any of these days, the source was more than 15 times brighter than it was during the entire month-and-a-half-long first passage.”

It won’t happen again until May, 2014… But you can bet astronomers will be tuned in to catch the action!

Original Story Source: NASA / Fermi News.

Posted on by Nancy Atkinson

Reason to Serve Red Wine on the Space Station?

Cosmonauts gather to have some cognac on the Mir space station in 1997. The image was taken by NASA astronaut Jerry Linenger.

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Some new research may make NASA reconsider its “no alcohol in space” policy. A new study suggests that the “healthy” ingredient in red wine, resveratrol, may prevent the negative effects that weightlessness has on muscle and bone metabolism. This also could apply to people who live sedentary lifestyles.

The study had rats in the simulated the weightlessness of spaceflight, and the group that was fed resveratrol did not develop loss of bone mineral density or develop insulin resistance, as did those who were not fed resveratrol.

Weightlessness was simulated by hindlimb tail suspension, a common technique used to study weightlessness physiology. The control group that was not given resveratrol showed a decrease in soleus muscle mass and strength, the development of insulin resistance, and a loss of bone mineral density. The group receiving resveratrol showed none of these complications.

“There are overwhelming data showing that the human body needs physical activity, but for some of us, getting that activity isn’t easy,” said Gerald Weissmann, M.D., Editor-in-Chief of the journal Federation of the American Societies for Experimental Biology (FASEB). “A low gravity environment makes it nearly impossible for astronauts. For the earthbound, barriers to physical activity are equally challenging, whether they be disease, injury, or a desk job. Resveratrol may not be a substitute for exercise, but it could slow deterioration until someone can get moving again.”

Of course, resveratrol can be taken in supplement form, but why spoil the fun? It is well known that Russian cosmonauts have imbibed in space, although probably not on the International Space Station. Alexander Lazutkin, who served aboard the Mir space station has said that Russian doctors recommended alcohol for “neutralizing the harmful effect of the atmosphere,” to keep cosmonauts “in tone” and to neutralize tension.

Weissmann added that red wine could become the “toast of the Milky Way.”

The study was published in the FASEB Journal

Sources: EurekAlert, Cosmic Log

Posted on by Nancy Atkinson

Astronomy Cast Ep. 224: Orion

Orion Nebula. Image credit: Hubble

Most people know how to find two constellations: the Big Dipper, and Orion the Hunter. You can teach a small child to find Orion, and at the right time of year, they’ll find it in seconds. There’s so much going on in this spectacular constellation, from the star formation in the Orion Nebula to mighty red supergiant Betelgeuse, ready to explode. Let’s learn about the history and science of the constellation Orion.

Click here to download the episode.

Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

Orion shownotes and transcript.