Posted on by Nancy Atkinson

Claim of Alien Life in Meteorites Needs Further Review

Image of permineralized remains in the one of the meteorites studied by Richard Hoover. Credit: Journal of Cosmology

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A recent paper published by a NASA scientist claims the discovery evidence of fossil bacteria in a rare subclass of carbonaceous meteorite. The claims are extraordinary, and were the paper published somewhere other than the Journal of Cosmology, (and given an “exclusive preview” on Fox News) more people might be taking this seriously. But, even so, the topic went viral over the weekend.

Titled “Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites” and written by NASA scientist Dr. Richard Hoover of the Marshall Space Flight Center, the paper makes the bold claim that meteorites found in France and Tanzania in the 1800s (the Alais, Ivuna, and Orgueil CI1 meteorites) have clear evidence pointing to space-dwelling microbes, with inferences of panspermia — the theory that microbes brought to Earth in comets and meteorites could have started life on our planet. “The implications,” says an online synopsis of the paper, “are that life is everywhere, and that life on Earth may have come from other planets.”

The paper states: “Filaments found in the CI1 meteorites have also been detected that exhibit structures consistent with the specialized cells and structures used by cyanobacteria for reproduction (baeocytes, akinetes and hormogonia), nitrogen fixation (basal, intercalary or apical heterocysts) and attachment or motility (fimbriae).”

Dr. Chris McKay, a planetary scientist and astrobiologist at NASA Ames Research Center, pointed out to Universe Today that Hoover’s claims are “extraordinary, because of the ecological setting implied. Cyanobacteria live in liquid water and are photosynthetic.”

McKay said finding heterocysts (cells formed by some filamentous cyanobacteria) would certainly be indicative of life from an actively thriving environment. “The implication of these results is that the meteorite hosted a liquid water environment in contact with sunlight and high oxygen,” he told Universe Today in an email.

Several scientists from various fields have written commentaries on this, (see astronomer Phil Plait’s take, biologist PZ Myers (from my alma mater) and microbiologist Rosie Redfield (who refuted the “arsenic life” finding late last year), and there’s tons more about this available, and Alan Boyle at MSNBC’c Cosmic Log is keeping a running update) but everyone seems to agree that verifying that the structures — rods and spheres seen in rock — are actually fossilized bacteria is very difficult to do.

Image at 1000 X of multiple filaments and sheaths embedded in Orgueil meteorite. Credit: Journal of Cosmology

There have been previous reports of bacteria in meteorites, but most have turned out to be contamination or misunderstanding of the microscopic structures within rocks (remember the Alan Hills Meteorite claim from 1996 –which is still widely controversial.) It turns out that Dr. Hoover has reported fossil bacteria previously, but none have actually been proven. And, it also turns out that Hoover’s paper was submitted to the Astrobiology Journal in 2007, but the review was never completed.

“Richard Hoover is a careful and accomplished microscopist so there is every reason to believe that the structures he sees are present and are not due to contamination,” McKay said. “If these structures had been reported from sediments from a lake bottom there would be no question that they were classified correctly as biological remains.”

There are two possibilities, McKay said. “One, the structures are not biological but are chance shapes. In a millimeter square area of meteorite there are million possible 1 micron squares. Perhaps any diversity of shapes can be found if searching is extensive.”

Or the second possibility, McKay said is that “the environments on meteorites are, or were, radically different from what we would expect. There are suggestions for how meteorite parent bodies could have sustained interior liquid water. But not in a way that could have the liquid water exposed to sunlight. It also seems unlikely that high oxygen concentrations would be implied.”

There’s also the question of why Hoover would choose to publish in the somewhat dubious Journal of Cosmology, an open access, but supposedly peer-reviewed online journal, which has come under fire for errors found in some of their articles, and for the rather sensational claims made by some of the papers published within.

But word also was released by the Journal of Cosmology that they will cease publication in May 2011. In a press release titled, “Journal of Cosmology To Stop Publishing–Killed by Thieves and Crooks,” (posted by journalist David Dobbs), the press release said that the “JOC threatened the status quo at NASA,” and that “JOC’s success posed a direct threat to traditional subscription based science periodicals, such as “science” magazine; just as online news killed many newspapers. Not surprisingly, JOC was targeted by science magazine and others who engaged in illegal, criminal, anti-competitive acts to prevent JOC from distributing news about its online editions and books.”

UPDATE: NASA has released a statement on Hoover’s paper, saying that “NASA cannot stand behind or support a scientific claim unless it has been peer-reviewed or thoroughly examined by other qualified experts. This paper was submitted in 2007 to the International Journal of Astrobiology. However, the peer review process was not completed for that submission. NASA also was unaware of the recent submission of the paper to the Journal of Cosmology or of the paper’s subsequent publication. Additional questions should be directed to the author of the paper.” – Dr. Paul Hertz, chief scientist of NASA’s Science Mission Directorate in Washington

But Hoover’s work is generating a huge buzz.

The journal’s editor in chief, Rudy Schild of the Harvard-Smithsonian Centre for Astrophysics, said Hoover is a “highly respected scientist and astrobiologist with a prestigious record of accomplishment at NASA. Given the controversial nature of his discovery, we have invited 100 experts and have issued a general invitation to over 5,000 scientists from the scientific community to review the paper and to offer their critical analysis.”

“No other paper in the history of science has undergone such a thorough analysis, and no other scientific journal in the history of science has made such a profoundly important paper available to the scientific community, for comment, before it is published,” Schild added. Those commentaries will be published March 7 through March 10, and can be found here.

Certainly, further review of Hoover’s work needs to be conducted.

Posted on by Nancy Atkinson

More Asteroids Could Have Made Life’s Ingredients

This artist's concept uses hands to illustrate the left and right-handed versions of the amino acid isovaline. Credit: NASA/Mary Pat Hrybyk-Keith

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From a NASA press release:

A wider range of asteroids were capable of creating the kind of amino acids used by life on Earth, according to new NASA research. Amino acids are used to build proteins, which are used by life to make structures like hair and nails, and to speed up or regulate chemical reactions. Amino acids come in two varieties that are mirror images of each other, like your hands. Life on Earth uses the left-handed kind exclusively. Since life based on right-handed amino acids would presumably work fine, scientists are trying to find out why Earth-based life favored left-handed amino acids.

In March, 2009, researchers at NASA’s Goddard Space Flight Center in Greenbelt, Md., reported the discovery of an excess of the left-handed form of the amino acid isovaline in samples of meteorites that came from carbon-rich asteroids. This suggests that perhaps left-handed life got its start in space, where conditions in asteroids favored the creation of left-handed amino acids. Meteorite impacts could have supplied this material, enriched in left-handed molecules, to Earth. The bias toward left-handedness would have been perpetuated as this material was incorporated into emerging life.

In the new research, the team reports finding excess left-handed isovaline (L-isovaline) in a much wider variety of carbon-rich meteorites. “This tells us our initial discovery wasn’t a fluke; that there really was something going on in the asteroids where these meteorites came from that favors the creation of left-handed amino acids,” says Dr. Daniel Glavin of NASA Goddard. Glavin is lead author of a paper about this research published online in Meteoritics and Planetary Science January 17.

This is a photo of a carbon-rich meteorite analyzed in the study. Credit: Antarctic Meteorite Laboratory/NASA Johnson Space Center

“This research builds on over a decade of work on excesses of left-handed isovaline in carbon-rich meteorites,” said Dr. Jason Dworkin of NASA Goddard, a co-author on the paper.

“Initially, John Cronin and Sandra Pizzarello of Arizona State University showed a small but significant excess of L-isovaline in two CM2 meteorites. Last year we showed that L-isovaline excesses appear to track with the history of hot water on the asteroid from which the meteorites came. In this work we have studied some exceptionally rare meteorites which witnessed large amounts of water on the asteroid. We were gratified that the meteorites in this study corroborate our hypothesis,” explained Dworkin.

L-isovaline excesses in these additional water-altered type 1 meteorites (i.e. CM1 and CR1) suggest that extra left-handed amino acids in water-altered meteorites are much more common than previously thought, according to Glavin. Now the question is what process creates extra left-handed amino acids. There are several options, and it will take more research to identify the specific reaction, according to the team.

However, “liquid water seems to be the key,” notes Glavin. “We can tell how much these asteroids were altered by liquid water by analyzing the minerals their meteorites contain. The more these asteroids were altered, the greater the excess L-isovaline we found. This indicates some process involving liquid water favors the creation of left-handed amino acids.”

Another clue comes from the total amount of isovaline found in each meteorite. “In the meteorites with the largest left-handed excess, we find about 1,000 times less isovaline than in meteorites with a small or non-detectable left-handed excess. This tells us that to get the excess, you need to use up or destroy the amino acid, so the process is a double-edged sword,” says Glavin.

Whatever it may be, the water-alteration process only amplifies a small existing left-handed excess, it does not create the bias, according to Glavin. Something in the pre-solar nebula (a vast cloud of gas and dust from which our solar system, and probably many others, were born) created a small initial bias toward L-isovaline and presumably many other left-handed amino acids as well.

One possibility is radiation. Space is filled with objects like massive stars, neutron stars, and black holes, just to name a few, that produce many kinds of radiation. It’s possible that the radiation encountered by our solar system in its youth made left-handed amino acids slightly more likely to be created, or right-handed amino acids a bit more likely to be destroyed, according to Glavin.

It’s also possible that other young solar systems encountered different radiation that favored right-handed amino acids. If life emerged in one of these solar systems, perhaps the bias toward right-handed amino acids would be built in just as it may have been for left-handed amino acids here, according to Glavin.

The research was funded by the NASA Astrobiology Institute (NAI), which is administered by NASA’s Ames Research Center in Moffett Field, Calif.; the NASA Cosmochemistry program, the Goddard Center for Astrobiology, and the NASA Post Doctoral Fellowship program. The team includes Glavin, Dworkin, Dr. Michael Callahan, and Dr. Jamie Elsila of NASA Goddard.

Posted on by Ken Kremer

“Astrobiology” Parody Video of Ke$ha’s “We R Who We R”

Wanna get turned on by … “Astrobiology” ?? Are we alone in the universe?

Well check out just this newly-released music video parody of Ke$ha’s hit song “We R Who We R” – “Astrobiology.”

Suspend your disbelief. It’s different. It’s cool. And it’s very clever.

And .. It’s even better the second time around when you listen to the lyrics more closely … combined with the shocking video .. Featuring beautiful maidens and alien dolls galore. Continue reading ““Astrobiology” Parody Video of Ke$ha’s “We R Who We R””

Posted on by Nancy Atkinson

Astronomy Cast Ep. 209: Exotic Life

Is this arsenic based life?

We don’t like to cover news on Astronomy Cast, but sometimes there’s a news story that’s interesting, complicated, and rapidly unfolding – and it happens to cover an area that we haven’t talked much about. So today we thought we’d talk about the discovery of arsenic-based life, and exotic forms of life in general. Maybe we need to redefine our definition of life. Or maybe we just got introduced to some distant cousins.

Click here to download Episode 209: Exotic Life
Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

Episode 209 Show notes and transcript

Posted on by Nancy Atkinson

Scientists from Arsenic Bacteria Paper Respond to Criticisms

Backlash from the “arsenic life” paper that was published on December 2, is still ongoing. Some of the criticism has been about the science, while much more criticism has been about the coverage of the news and also how NASA introduced, or “teased” the public with news, using the words “astrobiology” and “extraterrestrial life” in their announcement of an upcoming press conference. Today, at the American Geophysical Union conference, one of the team scientists, Ron Oremland discussed the fallout from the news coverage, and I’ll be providing an overview of that shortly. At about the same time, the science team released a statement and some FAQ’s about the science paper. Below is that statement and the information the science team provided.

Continue reading “Scientists from Arsenic Bacteria Paper Respond to Criticisms”

Posted on by Nancy Atkinson

Forests Might Be Detectable on Extrasolar Planets

Trees on an alien world? No, a dune field on Mars with sand flows. Credit: NASA/JPL/U of Arizona

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Excitingly, we’ve been able to detect the composition of atmospheres on a handful of planets orbiting other stars. But if next-generation space observatories go online within the next couple of decades, some scientists propose using a new technique to determine details such as tree-like multicellular life on extrasolar planets.

While previous studies have discussed the likelihood of detecting life on exoplanets through signs of biogenic gases in the atmosphere, or seeing “glints” of light off oceans or lakes, those technique are limited in that, for example, biogenic gases could be signs of either single-celled or multicellular life – not providing much detail — and as we’ve seen from Titan, glints off planetary bodies do not necessarily come from water-filled lakes.

Researchers Christopher Doughty and Adam Wolf from the Carnegie Institution propose using a technique that Earth-orbiting satellites already use to in order to determine types of crops and land cover, as well as cloud detection, atmospheric conditions and other applications.

Called Bidirectional Reflectance Distribution Function (BRDF), this type of remote sensing determines the causes of differing reflectance at different sun- and view-angles. For example, trees cast shadows on the planet, and the large-scale pattern of shadows would make the light reflected off the vegetation to take on specific brightness and color characteristics.

“BRDF arises from the changing visibility of the shadows cast by objects,” the researchers wrote in their paper, “and the presence of tree-like structures is clearly distinguishable from flat ground with the same reflectance spectrum. We examined whether the BRDF could detect the existence of tree-like structures on an extrasolar planet by using changes in planetary albedo as a planet orbits its star.”

BRDF and different light reflection for various planetary sufaces. Credit: Wolfgang Lucht.

They used a computer model to simulate vegetation reflectance at different planetary phase angles and added both simulated and real cloud cover to calculate the planetary albedo for a vegetated and non-vegetated planet with abundant liquid water.

Depending on how accurately planetary cloud cover can be resolved, as well as the sensitivity instruments on proposed missions such as the Terrestrial Planet Finder, this technique could theoretically detect tree-like multicellular life on exoplanets in about 50 nearby stellar systems.

The angles of the spacecraft, the planet and its sun would have to be taken into account but the team says these characteristics would change in predictable ways over time, producing a detectable pattern.

If vegetation on the exoplanet was wide¬spread enough, it would affect the reflective properties of the whole planet.

“We found that even if the entire planetary albedo were rendered to a single pixel, the rate of increase of albedo as a planet approaches full illumination would be comparatively greater on a vegetated planet than on a non-vegetated planet,” they said.

Doughty and Wolf’s paper appeared in the journal Astrobiology.

Posted on by Nancy Atkinson

NASA Finds a “Weird” Kind of Life on Earth

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.

Sources: Science, paper

Posted on by Nancy Atkinson

Habitable Environments Could Exist Underground on Mars

Possible Phyllosilicate-Rich Area in Syrtis Major. Credit: NASA/JPL/University of Arizona

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Data from the Mars Reconnaissance Orbiter suggests that there could be habitable environments underground on Mars – in the past, and perhaps even today. Scientists discovered evidence of long-sought-after hydrothermally altered carbonate-bearing rocks which were once deep within the Red Planet, exposed within an impact crater. “Carbonate rocks have long been a Holy Grail of Mars exploration for several reasons,” said Joseph Michalski from the Planetary Science Institute. He explained that on Earth, carbonates form with the ocean and within lakes, so the same could be true for ancient Mars. “Such deposits could indicate past seas that were once present on Mars. Another reason is because we suspect that the ancient Martian atmosphere was probably denser and CO2-rich, but today the atmosphere is quite thin so we infer that the CO2 must have gone into carbonate rocks somewhere on Mars.”

This unique mineralogy was spotted within the central peak of a crater to the southwest of a giant Martian volcanic province named Syrtis Major. With infrared spectra from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), planetary geologists detected the hydrothermal minerals from their spectroscopic fingerprints. Visible images from the HiRISE camera (High Resolution Imaging Science Experiment) on board MRO show that the carbonates and hydrated silicate minerals occur within deformed bedrock that was exhumed by an ancient meteor impact that poked through the volcanic upper crust of Mars.

The carbonate-bearing rocks were once likely about 6 km (about 4 miles) underground. The carbonate minerals exist along with hydrated silicate minerals of a likely hydrothermal origin.

Syrtis Major Planum Channel and Depression. Credit: NASA/JPL/University of Arizona

While this is not the first detection of carbonates on Mars, Michalski said, “This detection is significant because it shows other carbonates detected by previous workers, which were found in a fairly limited spatial extent, were not a localized phenomenon. Carbonates may have formed over a very large region of ancient Mars, but been covered up by volcanic flows later in the history of the planet. A very exciting history of water on Mars may be simply covered up by younger lava!”

The discovery also has implications for the habitability of the Martian crust. “The presence of carbonates along with hydrothermal silicate minerals indicates that a hydrothermal system existed in the presence of CO2 deep in the Martian crust,” Michalski says. “Such an environment is chemically similar to the type of hydrothermal systems that exist within the ocean floor of Earth, which are capable of sustaining vast communities of organisms that have never seen the light of day.

“The cold, dry surface of Mars is a tough place to survive, even for microbes. If we can identify places where habitable environments once existed at depth, protected from the harsh surface environment, it is a big step forward for astrobiological exploration of the red planet.”

Michalski and co-author Paul B. Niles of NASA Johnson Space Center recently published the results in a paper titled “Deep crustal carbonate rocks exposed by meteor impact on Mars” in Nature Geoscience.

Source: Planetary Science Institute, Nature Geoscience

Posted on by Nancy Atkinson

Titan’s Atmosphere Could Produce Building Blocks of Life

Titan's thick haze. Image: NASA/JPL/Space Science Institute.

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Saturn’s moon Titan has long been thought to be an analog of early Earth, and a recent experiment demonstrates that amino acids and nucleotide bases — which are the basic building blocks of life on Earth – could very easily be under production in Titan’s hazy atmosphere. “Our intention was to figure out what goes on in Titan’s atmosphere using high resolution mass spectrometry,” said Sarah Horst, from the University of Arizona, a member of an international team conducting the research. “We found there could be a high number of some incredibly complex molecules being created.”

Two recent exciting discoveries led the team to try and find out more about Titan’s atmosphere: first, the discovery of high energy oxygen ions flowing into Titan’s atmosphere, and second, that there are high heavy molecular ions in the atmosphere – neither of which were expected.

“When you put two discoveries together, that leads us to possibility that oxygen can get incorporated into these large molecules and in turn, that may be incorporated into life,” Horst said in press briefing at the American Astronomical Society’s Division of Planetary Sciences meeting this week.

The intense radiation that hits the top of Titan’s thick atmosphere is capable of breaking apart even very stable molecules. The international team wanted to understand what happens as these molecules are broken apart in the atmosphere.

Working with a team in France, Horst, a graduate student, and her professor Roger Yelle, filled a reaction chamber with Titan-like atmosphere, (a cold plasma consisting of nitrogen, methane and carbon monoxide), and infused radio-frequency radiation as an energy source.

“What happens is that aerosols form in levitation — they float while forming — so this probably is very representative of Titan’s atmosphere,” Horst said. “We end up with really cool looking aerosols that have very similar sizes to aerosols that are inferred in Titan’s atmosphere.”

The molecules discovered in the aerosols include the five nucleotide bases used by life on Earth (cytosine, adenine, thymine, guanine and uracil) and the two smallest amino acids, glycine and alanine.

“The experiment showed that Titan’s atmosphere is capable of producing extremely complex molecules and has the potential for producing molecules that are important for life on Earth,” Horst said, but tempered her statement by adding, “however, this doesn’t mean there is life on Titan.”

She said if there were life on Titan, mostly likely it would use molecules that life on Earth would not use, as due to lack of liquid water, life would be completely different.

“But this tells that it is possible to make very complex molecules in the outer parts of an atmosphere,” Horst said. “We don’t need liquid water, we don’t need a surface.”

This also provides another option to how life may have started on Earth. The two main theories for how life began on Earth is that it was brought here by comets or asteroids or that it formed from a primordial soup zapped to life from lightning. But it may have formed from a primordial haze high in Earth’s atmosphere.
“This helps us to understand what processes began life on Earth and what could be happening on other exoplanets in the galaxy,” Horst said.

Source: DPS briefing

Posted on by Jerry Coffey

Is There Life On Other Planets

Temperature of Mars
What is the Temperature of Mars? Image credit: NASA/JPL

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Is there life on other planets? That has been a question raised from the early beginnings of science fiction. The notion was scoffed at as pure mind play for dreamers and the occasional grifter selling rides to the Moon. At least it was until we were able to reach into space and discover new facts and gather new intel.

The possibility of life on Mars(outside sci-fi books) had been proposed as early as the 1950’s, but there was no real way to prove or disprove the theory until the launch of Mariner 4 in 1965. The spacecraft was able to return the first photographs of the planet’s surface. The news was all bad for those who had hoped for signs of life on the planet. The surface was too extreme and desolate for any type of known life form. The Voyager probes found radiolabeled carbon dioxide, but no organic molecules. Those results give mixed signals and are inconclusive at best. The results have been used to support the possibility of a microorganism named Gillevinia straata.

The Phoenix lander touched down on the Martian surface in May of 2008. The lander dug a trench on the area of the northern pole. No bacteria was found but the samples did contain bound water and carbon dioxide. The most positive evidence of life in the Martian past are meteorites from the planet. 34 exist and 3 show signs of microscopic fossilized bacteria.

Another viable possibility for life on other planets would be those similar to Gliese 581c. These planets are within the habitable zone(for human life) of their main sequence star. These planets appear to have a temperature that would allow liquid water and atmosphere’s that seem spectroscopically close to Earth’s. The information that is needed would detail the greenhouse effect on these planets. If that was available, we would be able to determine suitability for human life.

All of our efforts to answer the question ‘Is there life on other planets?’ are based on finding life that is similar to that on Earth. That is a typically arrogant line of research. Where is it written that the Earth type of life form is pervasive?

We have written many articles about the possibility of life on other planets for Universe Today. Here’s an article about the life on other planets, and here’s an article about life on Mars.

If you’d like more info on the search for life on other planets, check out the NASA Astrobiology Institute Homepage, and here’s a link to NASA Planet Quest: Finding Life.

We’ve also recorded an entire episode of Astronomy Cast all about the Future of Astronomy. Listen here, Episode 188: The Future of Astronomy.