These tracks made by the Spirit rover early in the mission are certainly not there anymore. Credit: NASA/JPL/Cornell University
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The footprints and rover tracks on the Moon will be there for millions of years, as there is no wind to blow them away. But Mars is a different story. Researchers looking at the tracks left by the two Mars Exploration Rovers, Spirit and Opportunity have found that Mars wind storms can quickly erase any evidence the rovers had been there.
“It is humbling, said Paul Geissler, lead author of a recent paper on eolian — or wind — processes on Mars. “We make kilometer-long human graffiti on the surface of another planet and then Mars just wipes the slate clean for the next visitors!”
Erasure of Spirit’s tracks during the 2007 global dust storm. This pair of Rear Hazcam images documents the erasure of Spirit’s tracks during the global dust storm of 2007. The soil in which the tracks were emplaced was completely blown away by strong surface winds between (top) sol 1250 and (bottom) sol 1272 and replaced by soil transported from elsewhere. Erasure of Spirit’s tracks during the 2007 global dust storm. This pair of Rear Hazcam images documents the erasure of Spirit’s tracks during the global dust storm of 2007. The soil in which the tracks were emplaced was completely blown away by strong surface winds between (top) sol 1250 and (bottom) sol 1272 and replaced by soil transported from elsewhere. Credit: NASA/JPL, courtesy of Geissler, et al/JGU.
Geissler and his team were interested in how the Martian wind affects the surface, in the mechanisms and time-scales for the surface changes that could be seen across the globe.
Each of the rovers have left a trail of tracks in the soil that could be seen by orbiting spacecraft – the Mars Global Surveyor (no longer functioning) and the Mars Reconnaissance Orbiter – as well as in images from the rovers themselves.
From the images, the team was able to document the formation of the tracks and also their eventual erasure through the action of Martian winds.
They were a little surprised at the results.
“We anticipated that we would be able to see the rovers’ tracks in MRO HiRISE images and we *might* see some changes,” Geissler told Universe Today in an email, “ but I was surprised at how quickly the tracks disappeared!”
Geissler said that when he wrote his original proposal for the research (which was before MRO arrived at Mars), he thought it was likely they would not see any changes in the tracks over the duration of the mission.
This pair of images documents the erasure of rover tracks and rocket blasts at Opportunity’s landing site in Meridiani Planum over a period of more than a Martian year. Faint tracks leading from Eagle crater to Fram crater are pointed out in Figure 8 (top), acquired in April 2004. These tracks, and the conspicuous bright patches left by the landing rocket blasts, were largely absent from the early HiRISE image, Figure 8 (bottom) acquired November 2006). Remnant tracks were preserved at Fram crater (Figure 10). Image: NASA/JPL/Malin Space Science Systems/University of Arizona/JGR
“I expected the tracks to be slowly buried by dust settling out of the atmosphere or overprinted by dust-devils in Gusev crater,” he said. “Instead they are blown away by gusts of wind during episodic storms that only last a few days! I think the mechanisms of track erasure are interesting and somewhat surprising.”
While it might be sad for most of us to know the rover tracks are being erased, the scientists see it a little differently.
“I will confess to not feeling sad about it at all,” said Jim Bell, lead the lead scientist for the Panoramic cameras on the rovers, and a member of the Geissler’s research team. “Rather, it’s cool that the Martian environment is so dynamic, and tracking the tracks provides a neat science experiment to understand the role of dust and sand transport in modifying the current surface. So don’t be sad, be glad!
This sequence of images documents the appearance and disappearance of Opportunity’s tracks around Victoria Crater before and after the global duststorm of July 2007 and through 2009. Credit: NASA/JPL/University of Arizona, courtesy of Geissler, et al/JGU
As the “V” in the designation of V445 Puppis indicates, this star was a variable star located in the constellation of Puppis. It was a fairly ordinary periodic variable, although with a rather complex light curve, but still showing a distinct periodicity of about fifteen and a half hours. It wasn’t especially bright, yet something seemed to tug at my memory regarding the star’s name as I scanned through articles to write on. Just over a year ago, Nancy wrote a post on V445 Puppis stating it’s a supernova just waiting to happen. A new article challenges this claim.
In December of 2000, V445 Puppis underwent an unusual nova. It was first noticed on December 30th, but archival records showed the eruption began in early November of that year and reached a peak brightness on November 29th. The system was known to be a binary star system with a shared envelope in which the primary star was a white dwarf and thus, a nova was the most readily available explanation.
However, this wasn’t a normal nova. Spectroscopic observations early the next year showed the ejecta lacked the helium emission seen in classical novae in which hydrogen piles up on a white dwarf surface until it undergoes fusion into helium. Instead, astronomers saw lines of iron, calcium, carbon, sodium, and oxygen expanding at nearly 1,000 km/sec. This fit better with a proposed type of explosion where, instead of hydrogen collecting on the dwarf’s surface, it was helium and the eruption seen was a helium flash in which it was helium that underwent fusion. Slowly the star faded, and debris from the eruption cooled to form dust. Today, the star itself is completely obscured in the visible portion of the spectrum.
The 2009 paper by Woudt, Steeghs, and Karowska that Nancy cited, suggested accretion might continue until the white dwarf passed the Chandrasekhar limit and exploded as a type Ia supernova. However, the authors of the new paper, led by V. P. Goranskij at Moscow University, say that this 2000 detonation has effectively ruled out that possibility because an explosion of that magnitude would likely destroy the envelope of the donor star. Their evidence for this is the very same structure Woudt noted in his paper (shown above).
While the structure looks to be bipolar in nature, other observations have suggested that there is an additional component along the line of sight and that the structure is more of a doughnut shape. In this case, the total amount of material lost is higher than originally anticipated and must have come from from the envelope of the companion star. Additionally, observations in wavelengths able to pierce the dust have been unable to resolve a strong stellar source which suggests that the donor star’s envelope has been largely blown away as well. Additionally, this large and rapid loss of mass from the system may have broken the gravitational bond between the two stars and allowed the giant star to be ejected from the system, which would also preclude the possibility of a supernova in the future.
The conclusion is that V445 Puppis is not a candidate for a supernova of any type in the future. It’s own premature fireworks have likely destroyed whatever chance it may have had for an even grander show in the future.
Discovery on the launchpad. Credit: Alan Walters (awaltersphoto.com) for Universe Today
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NASA announced today that the launch of space shuttle Discovery for the STS-133 mission has been pushed back to no earlier than Feb. 3, 2011, to allow for more testing on the external tank stringers. Cracks on the stringers were found after the tank was loaded with cryogenic fuel for a subsequently scrubbed launch attempt in November.
“We’ve hit a point where there is no obvious answer for what has occurred,” said shuttle program manger John Shannon at a press briefing today, “so we have to take the next step and understand to very fine level the stress on the stringers and to find if that is a root cause of what happened to the STS-133 tank. I need to better understand the conditions to fly that fly tank confidently. It’s unfortunate we are not making the December launch window. But we want to make sure that we do this exactly right.”
The cracks appeared on two 21-foot-long, U-shaped aluminum brackets, called stringers, on the shuttle’s external tank. NASA repaired the cracks and reapplied foam to the exterior of the stringers. But they don’t understand the reasons the cracks appeared, and NASA managers feel this is likely a unique event.
“We don’t have any data that we have been flying with cracks all along,” said Shannon.
The launch window is open from Feb. 3 -10. This delay also moves the STS-134 launch from February to April.
This delay, however, doesn’t mean there won’t be any activity at the International Space Station. The crew for Expedition 26 launches on the Soyuz on Dec. 15, Japan’s HTV supply ship launches on January 20, a Progress resupply ship docks on Jan. 31, and ESA’s ATV resupply vehicle is scheduled for a February 15th launch.
NASA’s Bill Gerstenmaier said the teams will try to replicate what engineers think is the most leading cause is of the failure. “They will build up a stringer panel and put some defects in, the manufactured tolerances, and try to replicate the crack we saw during cryo loadings,” he said. “We’ll also do a test at cape where we load tank with cryogenic propellant and put some devices on the tank to monitor how it loads up and that will serve to validate the math models and the environment we see during loading.”
Gerstenmaier added that between those two tests, they should be able to understand what caused the cracks, but there is now way they can do those tests before December 17, the data NASA had been shooting for to launch STS-133.
“The teams have done tremendous job, but it’s time to pursue a different path,” he said. He also provided a quote from former NASA pioneer Hugh Dryden, who said the purpose of tests is to separate real from imaged problems and to reveal overlooked and unintended problems.
Artist illustration of Eris and its moons. Image credit: NASA
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Here’s part 2 of our conversation with astronomer Mike Brown. Yesterday, he talked about the latest findings on Eris, the Haumea controversy and more; today he talks about being known as the “killer” of Pluto, his reflections on Brian Marsden and his hopes for the New Horizons mission to Pluto.
Universe Today: You seem to actually relish the role of Pluto Killer…
Mike Brown: You know, I didn’t initially. I really wanted to be the thoughtful person who explained to people what was going on and I tried very hard. And the reason I have become a sort of more militantly Pluto-killer-ish over the past couple of years is because — against what I think is reason — there are other astronomers who have been militantly pro-Pluto and saying things that are generally misleading in public. And it pains me to have scientists say things that I know they don’t actually think are true.
To hear an astronomer say that there is no logical reason why you would come up with eight planets, it makes no scientific sense. No one can say that and actually believe it. There are good arguments for one side or the other and I would enjoy it more if they would make the arguments instead of just trying to sort of manipulate public opinion, but I don’t think they do. Mostly the small number of the pro-Pluto crowd tends to be more manipulative. I thought somebody needs to defend the very reasonable idea of eight planets, so I have taken on that role.
UT: The Pluto-is-a-planet people are definitely vociferous.
Mike Brown: And honestly, I think manipulative is the word. They don’t believe what they say, they know what they say is not true and they say it in ways that are deceitful. That is maybe a strong statement to make, but they know what they are saying is not true. That bothers me. You shouldn’t say things that you know is not true just to make a point.
UT: Could you talk a little about Brian Marsden? He played a rather big role in the book, and in how things turned out with your discoveries – and the planet debate. He’ll obviously be missed.
Mike Brown: I have a book sitting at home that I had actually signed that I was going to send to him, and I didn’t get a chance to do it. I’m really sad that he didn’t get to see it. Everybody has their ‘Brian Marsden story’, and some are versions of the same story where he was incredibly supportive of interesting things in the solar system. When we started finding these large objects, there were a lot of people who were less supportive and not really happy about the discoveries. Brian was just happy about everything – if you were discovering new objects or comets, or different observations of asteroids – he just loved it all and he was always the first, you could just hear it in his voice when you talked to him, he was just genuinely excited about these new things that were being discovered.
He can’t be replaced. I like the people at the minor planet center and I like what they are doing, but he was unique. We won’t ever replace that energy and enthusiasm and the absolute love of the solar system that he had.
UT: How much are you looking forward to the New Horizons mission flyby of Pluto – and do you have any inklings of what it might come across in the Kuiper Belt?
Mike Brown. Credit: CalTech
Mike Brown: It going to be really interesting. The funny thing is, the answer to that question three weeks ago was “I can’t wait because all of these objects are sort of the same out there in the Kuiper Belt, and going to the closest one, even if it is not the biggest one will really teach you about everything that is out there.” That statement is no longer true. With Eris and Pluto being so different, we won’t learn as much about Eris as I had initially hoped, but like everyone else, I’ll be waiting anxiously for those first pictures to come back. I can’t wait to see them. Every time we go somewhere we’ve never gone before we learn things – the things we learn are never the things you think you are going to learn. I’m prepared to be astounded.
I am looking forward to, as much if not more perhaps, the later flyby of New Horizons of a small KBO. I think that scientifically understanding the smaller more typical objects is perhaps even more important than understanding the rare, big crazy objects.
Artist concept of the New Horizons spacecraft. Credit: NASA
UT: And are you still actively looking for objects out there?
Brown: Yes, we are looking very hard in the southern hemisphere now. We’ve finished the northern hemisphere, at least the bright objects, so I don’t think there will be too many more big ones discovered.
For the northern hemisphere, we knew that — at least — Clyde Tombaugh had been there first. We weren’t going to find something as bright as Pluto in the northern hemisphere because Clyde would have found it. In the southern hemisphere, it is basically wide open, because there was no Clyde Tombaugh, and we’re not even quite sure what the limit is. There’s not something 6th magnitude out there because someone would have seen it, but I don’t know how bright the brightest thing could be – that doesn’t mean that there’s something that bright there, but every day when we’re looking the possibilities are exciting.
UT: What telescopes are you using?
Brown: We have two that are working right now. One is actually an old data set from a near Earth asteroid survey and we are reprocessing the data in a way to make is sensitive to the types of objects we are looking for. This is the Uppsala ½ meter telescope at Siding Spring in Australia. It is the same telescope and the same data that the Catalina Sky Survey uses for the southern hemisphere.
And then as soon as telescope is finally online, we’ll use the Australian National University Skymapper telescope, which is kind of a Pan-STARRS south type of telescope that can do big surveys of the southern skies for many different purposes, including finding large Kuiper Belt objects.
It is fun to know again that some morning we might wake up and find something big and cool. That is always a fun way to go through life.
A few favorite quotes and personal thoughts from NASA’s astrobiology press conference:
“So we end a week of fiction and now start with the facts,” said Dwayne Brown, Public Affairs Officer from NASA Headquarters.
From principal investigator Felisa Wolfe-Simon, a NASA astrobiology research fellow:
“I’m always interested in exceptions to the rules.”
“These are not little potatoes, these are microbes which scientists lovingly call little bugs, but they are not bugs, they are microbes that look ordinary but are doing something extraordinary.”
“We took mud from Mono Lake and wanted to see if anything would grow if it was rich in everything else it needed, but instead of phosphorous we gave it arsenic. Not only did the microbes cope but they grew and thrived and that was amazing. Nothing should have grown. We wanted to find out what was happening, and we found the microbes were taking up the arsenic, and when we isolated the DNA, we found the arsenic was in there.”
“This will help inform us of life on our own planet and provide insight when we find it somewhere else.”
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“Finding that microbes are possibly able to live without phosphorous – the idea that I’m sitting here discussing this is shocking,” said James Elser, a professor at Arizona State University. “This is quite a remarkable report.”
“I’m the curmudgeon here to throw a wet blanket on things,” said Steven Benner, a distinguished fellow from theFoundation for Applied Molecular Evolution. “I brought my Richard Feynman props with me. He said ‘science begins when you distrust the experts.’ But this is an exceptional scientific result, a clash of contradicting cultures.”
And my favorite: “This is a phenomenal finding,” said Mary Voytek, director of NASA’s Astrobiology Program. “We are talking about taking the fundamental building blocks of life and replacing one of them with an unusual, perhaps not unpredicted, but another compound. In our mind this is the equivalent, and some of us remember seeing the original Star Trek episodes, of “Devil in the Dark” and the Horta. This in our mind is the equivalent of finding that Horta which is a silicon based life, substituting carbon, which is what we think all life forms are made of, with silica. Now we are talking about an organism that we think we are talking about an organism that, if not replacing all of it, appears to be using another fundamental component of life. The story is not entirely carbon. Nitrogen, phosphorus, and the other essential elements–it is replacing arsenic for phosphorus. This is a huge deal.”
It’s life, Jim, but not as we know it.
Now that the dust and hysteria has settled from NASA’s press conference on the new astrobiology discovery, I have to admit, this was an unusual week. As always, I had the opportunity to see the Science press releases as early as last Sunday, but since I normally write about rocket launches and space mission results, I didn’t pay too much attention to this biology-related topic. It just entailed some unusual stuff here on Earth, which could mean life anywhere might be more varied and different than we thought. I knew it would be of great interest to the astrobiology community, but figured the general public would probably go “whaa?” as far as the science. But then the world started spinning out of control over NASA’s “big announcement.”
While NASA routinely sends out announcements of upcoming press conferences, and then people start to speculate of what will be announced, this one was off the charts. The fact that the press release was embargoed and “secret” – and some people had access and others didn’t — seemed to fan the flames.
There was a buzz on Twitter, on various websites, and even across the mainstream media. Personal acquaintances who normally pay no attention to my work actually started calling and emailing me to find out what I knew about NASA’s announcement about extraterrestrial life.
While some people feel that the embargoed news system is broken in today’s fast-paced, social media world, I actually like the system, and agree with the Associated Press’s Seth Borenstein, who was quoted in the Columbia Journalism Review:
“While the embargo system may have issues, I embrace it because it gives us a chance to provide context, outside comment and above all get it right,” he wrote in an e-mail. “In this hectic media environment, more than ever the world needs science reporters and editors who understand what’s happening, can tell fact from speculation, put phrases in context, be definitive and above all get it right. This whole sorry affair provides the proof of that.”
But, the CJR, asks, “Can anything be done to discourage misinformed, runway blogging that can lead to so much public confusion?”
It seems those who don’t have access to the embargoed releases want to be “first” in breaking the news. But as is often the case, the actual story is not nearly as sensational as all the speculation.
Borenstein again: “As a reporter who has covered astrobiology for more than a decade, I can tell you it has nothing to do with little green men or anything alien. Astrobiology is a series of little steps on Earth and beyond. Experienced science reporters know how to interpret the press release that got the speculation going. There is still a place for solid journalism.”
And in my bid for solid journalism, here’s my ode to the weird bacteria (with apologies to Walt Whitman):
I Sing the Bacterium Arsenic
Oh, little GFAJ-1
The potato-looking gammaproteobacteria, straight from Mono Lake
You are the arsenic to my phosphorous,
The sustenance to my poison
The arsenate backbone to your altered DNA,
The yin to the rest of the world’s yang,
The Horta to my Trekkieness,
And the reality to everyone’s wild speculation.
U.S. Air Force X-37B reusable space plane. Credit: Boeing, US Air Force.
The X-37B mini space shuttle made a stealth landing during the early morning hours, landing at Vandenberg Air Force base at 1:16 a.m. PDT (0916 GMT) today (Friday, Dec. 3.) The US Air Force’s first unmanned space plane successfully glided to a landing after nearly 225 days in space.
X-37B program manager Lt Col Troy Giese stated moments after landing, “We are very pleased that the program completed all the on-orbit objectives for the first mission.”
Above is an infrared camera view of the space plane taxiing after landing this morning.
The space plane’s exact mission was not divulged, and the Air Force did not immediately report anything about the performance of the spacecraft or if any issues arose.
The X-37B’s mission is to “demonstrate a reliable, reusable, unmanned space test platform for the United States Air Force,” according to a fact sheet put out by the military. “Objectives of the OTV program include space experimentation, risk reduction and concept of operations development for reusable space vehicle technologies.”
Enceladus and Dione line up for the Cassini camera. Credit: NASA/JPL/Space Science Institute
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Here are a few raw images from the Cassini spacecraft’s most recent flyby of Enceladus. The probe seems to be in good health following several weeks in safe mode, after a bit flipped in the command and data subsystem computer. This prevented the spacecraft from registering and following instructions. But she appears to be humming along just fine now, and snapped this great picture of Enceladus and Dione yesterday (have to quote @lukedones on Twitter: “Dione going in the corner pocket!”) Cassini focused on the Enceladus during a close flyby on November 30, so see more below, including a wonderful shot of a veritable curtain of geyser “spray.”
A good look at the spray from the fissures on Enceladus. NASA/JPL/Space Science Institute Enceladus, backdropped by Saturn's rings. Credit: NASA/JPL/ Space Science Institute. Closeup of Enceladus. Credit: NASA/JPL/Space Science Institute. An even closer closeup of Enceladus. Credit: NASA/JPL/Space Science Institute.
The active star forming region NGC 7538. Image by Fred Calvert/Adam Block/NOAO/AURA/NSF
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Often overshadowed by the more famous Bubble Nebula which lies nearby, NGC 7538 is an exciting emission and reflection nebula located in Cepheus. While it is often overlooked by amateur astronomers, professionals looking to study stellar formation find it an exciting target as it is the host to ongoing star formation, including the largest known protostar.
Because of the dusty nature of this region, studies targeting the nebula are frequently conducted in longer wavelengths, ranging from the infrared to the radio. Previous studies have put the age of the forming stars at around ~1-4 million years and at a distance of ~2.8 kiloparsecs. Within it, several individual sub groups of star formation seem to have occurred. Among some of the more interesting individual forming stars are NGC 7538S and MM 1.
Observations from earlier this year targeted NGC 7538S. This protostar is embedded in a collapsing core of approximately 85 – 115 solar masses and hosts a rotating accretion disc as well as large outflows of material. Although the star has not finished forming, the conditions are right for it to form into a high mass B star and is undergoing accretion at an unusually high rate of 1/1000th of a solar mass per year.
More recently another paper explores several other forming stars in the region including the massive MM 1. This star is already estimated to have accumulated 20-30 solar masses and be well on the way to forming an O class star. But it’s not done yet. Radial velocity measurements of molecules in the protostar’s vicinity indicate it’s still undergoing large amounts of accretion, mostly from its equatorial plane. Numerous studies have shown that this massive star is creating powerful jets.
In addition, this new study identifies an additional eight cores forming into young stars near MM 1. These cores are interesting because they exist in regions where the density and temperature were not expected to be sufficiently high to induce star formation. This suggests that their formation was not uniquely due to a self induced collapse, but rather, triggered by shock waves or magnetic fields. Although no studies have searched for the signs of magnetic fields in the region, there are indications that numerous shock waves exist. Additionally, four of these cores have mass available to them similar to that of MM 1 which may allow them to form into a grouping of high mass stars similar to the famous Trapezium in Orion. These stars all exist in a narrowly confined region of about 1 light year, which is also similar to the separation of the Trapezium. Many of the newly discovered cores have large outflows and maser emission as well.
Further studies on this region will certainly uncover new protostars and assist astronomers in understanding how clusters of stars form. Already, astronomers have used it to help probe the Initial Mass Function which describes the number of stars forming for various masses. Additionally, with small clusters of stars like the Trapezium being common, catching one in the act of forming may help astronomers determine just how they form.
Mono Lake in California, with the bacteria (inset) that lives there. Credit: Science
No, NASA has not found life on another planet, but has found life here on Earth that is almost “alien” to our narrow, phosphate-based view of life. Scientists have discovered — or “trained,” actually — a type of bacteria that can live and grow almost entirely on a poison, arsenic, and incorporates it into its DNA. This “weird” form of life, which can use something other than phosphorus — what we think of as a basic building block of life — is quite different from what we think of as life on Earth. It doesn’t directly provide proof of a “shadow biosphere,” a second form of life that lives side-by-side with other life on our planet, but does suggest that the requirements for life’s beginnings and foundations may be more flexible than we thought. This means life elsewhere in the solar system and beyond could arise in a multitude of conditions.
“Our findings are a reminder that life-as-we-know-it could be much more flexible than we generally assume or can imagine,” said Felise Wolfe-Simon, lead author of a new paper in Science. “If something here on Earth can do something so unexpected, what else can life do that we haven’t seen yet?”
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The salt-loving bacteria, strain GFAJ-1 of the Halomonadaceae family of Gammaproteobacteria,came from the toxic and briny Mono Lake, near Yosemite Park in California. The lake has no outlet, so over millennia has become one of the highest natural concentrations of arsenic on Earth.
Although the bacteria did not subsist entirely on arsenic in the lake, the researchers took the bacteria in the lab grew it in Petri dishes in which phosphate salt was gradually replaced by arsenic, until the bacteria could grow without needing phosphate, an essential building block for various macromolecules present in all cells, including nucleic acids, lipids and proteins.
Using radio-tracers, the team closely followed the path of arsenic in the bacteria; from the chemical’s uptake to its incorporation into various cellular components. Arsenic had completely replaced phosphate in the molecules of the bacteria, right down its DNA.
“Life as we know it requires particular chemical elements and excludes others,” said Ariel Anbar, a biogeochemist and astrobiologist from Arizona State University. “But are those the only options? How different could life be? One of the guiding principles in the search for life on other planets, and of our astrobiology program, is that we should ‘follow the elements. Felisa’s study teaches us that we ought to think harder about which elements to follow.”
Felisa Wolfe-Simon, right, a NASA astrobiology research fellow in residence at the USGS, and Ronald Oremland, an expert in arsenic microbiology at the USGS, examine sediment in August 2009 from Mono Lake in eastern California. Credit: Henry Bortman
Wolfe-Simon added, “We took what we do know about the ‘constants’ in biology, specifically that life requires the six elements CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur) in three components, namely DNA, proteins and fats, and used that as a basis to ask experimentally testable hypotheses even here on Earth.”
The idea that arsenic might be a substitute for phosphorus in life on Earth, was proposed by Wolfe-Simon and developed into a collaboration with Anbar and theoretical physicist and cosmologist Paul Davies. Their hypothesis was published in January 2009, in a paper titled “Did nature also choose arsenic?” in the International Journal of Astrobiology.
“We not only hypothesized that biochemical systems analogous to those known today could utilize arsenate in the equivalent biological role as phosphate,” said Wolfe-Simon “but also that such organisms could have evolved on the ancient Earth and might persist in unusual environments today.”
This new research is the first time that shows a microorganism is able to use a toxic chemical to sustain growth and life.
The Stratospheric Observatory for Infrared Astronomy, or SOFIA, 747SP basks in the light of a full moon shining over California’s Mojave Desert. NASA photographer Tom Tschida shot this telephoto image on October 22, 2010 NASA Photo / Tom Tschida
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SOFIA, NASA’s airplane-based Stratospheric Observatory for Infrared Astronomy made its first science flight on Wednesday, to help demonstrate the aircraft’s potential to make discoveries about the infrared universe. The new observatory uses a modified 747 airplane to carry a German-built 2.5 meter (100 inch) reflecting telescope, and on its initial flight to gather science data, the plane flew for about 10 hours.
“These initial science flights mark a significant milestone in SOFIA’s development and ability to conduct peer-reviewed science observations,” said NASA Astrophysics Division Director Jon Morse. “We anticipate a number of important discoveries from this unique observatory, as well as extended investigations of discoveries by other space telescopes.”
SOFIA is anticipated to have a 20-year lifespan that will enable a wide variety of astronomical science observations not possible from other Earth and space-borne observatories.
Cruising at altitudes between 39,000 and 45,000 feet, researchers hope to study how stars and planets are born, how organic substances form in interstellar space, and how supermassive black holes feed and grow.
SOFIA is a 100-inch diameter infrared telescope, and the instruments can analyze light from a wide
range of celestial objects, including warm interstellar gas and dust of bright star forming regions, by observing wavelengths between 0.3 and 1,600 microns. A micron equals one millionth of a meter. For
comparison, the human eye sees light with wavelengths between 0.4 and 0.7 microns.
The first three science flights, phase one of SOFIA’s early science program, will employ the Faint Object InfraRed Camera for the SOFIA Telescope (FORCAST) instrument developed by Cornell University and
led by principal investigator Terry Herter. FORCAST observes the mid-infrared spectrum from five to 40 microns.
Researchers used the FORCAST camera on SOFIA during a test flight two weeks ago to produce infrared images of areas within the Orion star-formation complex, a region of the sky for which more extensive
data were collected during the Nov. 30 flight. The image below is of this region. You can see more images at this link.
This infrared image of the heart of the Orion star-formation complex was taken by SOFIA’s FORCAST mid-infrared camera. Credit: NASA
SOFIA flies from NASA’s Dryden Aircraft Operations Facility in Palmdale, California.
