Extraterrestrial life

From New Scientist: “NASA has been shameful in not searching for extraterrestrial life and at the same time claiming that’s one of the motivations for their programmes,” says Chris McKay, an astrobiologist at NASA’s Ames Research Center in Mountain View, California. “The Mars programme counts life as the reason for the programme, and then the missions NASA implements don’t even approach the question at all.” McKay cites the example of the upcoming Mars 2020 rover, which will primarily search for signs that life once existed on the Red Planet. Rather than hunting for alien microbes today, the rover will set aside samples that NASA hopes some future mission will bring back to Earth, where we can probe them for signs Read More ›

But so? Mars is interesting. But, apart from life, why do we study it with such intensity? Just wondeing. From ScienceDaily: “Because the climate on Mars fluctuates with larger swings in axial tilt, and ice will distribute differently for each swing, Mars would look substantially different in the past than it does now,” said Smith. “Furthermore, because Mars has no oceans at present, it represents a simplified ‘laboratory’ for understanding climate science on Earth.” Detailed measurements of ice thickness show that about 87,000 cubic kilometers of ice have accumulated at the poles since the end of the last ice age about 370,000 years ago; the majority of the material accumulated at the martian north pole. This volume is equivalent to Read More ›

From physicist Paul Davies (who was on a committee(2009) to discuss what to do if aliens landed) Scientific American: Another common argument is that the universe is so vast there just has to be life out there somewhere. But what does that statement mean? If we restrict attention to the observable universe there are probably 1023 planets. Yes, that’s a big number. But it is dwarfed by the odds against forming even simple organic molecules by random chance alone. If the pathway from chemistry to biology is long and complicated, it may well be that less than one in a trillion trillion planets ever spawns life. Affirmations that life is widespread are founded on a tacit assumption that biology is not Read More ›

From MacGregor Campbell at at New Scientist: We are used to thinking small when it comes to alien life. Our list of living worlds has a sole data point, Earth, and even our convivial planet seems to have been a tricky place for life to get started. How could we expect more than a self-replicating bag of biomolecules anywhere else? That might be too lofty a view of Earth. After all, huge areas of our planet, including the poles and deserts, are rather barren. And whole epochs of time were inhospitable to life. More. So, of course, “There should be worlds out there so balmy they make Earth look stale, and there are signs of one just four light years Read More ›

Further to Will the shooting stars please rise? Rob Sheldon writes to say Just to set the record straight. The meteorite they showed in the article, was not a piece of iron, it was a “framboid” from an extinct comet made up of Fe3O4 “magnetite”. The reason it looks all lumpy, is that it is a ball made up of ball bearings, each one small enough to be spontaneously magnetized. These ball bearings are not random crystallization of iron, rather they are biominerals, made by living organisms, and far from equilibrium. The closest analog is a Fe3S4 mineral “goethite” found in deep gold mines in South Africa. We don’t know much about the organisms that make them–they look to be Read More ›

From BBC News: It has also detected nine small planets within so-called habitable zones, where conditions are favourable for liquid water – and potentially life. The finds are contained within a catalogue of 1,284 new planets detected by Kepler – which more than doubles the previous tally. … The Nasa Ames researcher said the Kepler mission was part of a “larger strategic goal of finding evidence of life beyond Earth: knowing whether we’re alone or not, to know… how life manifests itself in the galaxy and what is the diversity”. She added: “Being able to look up to a point of light and being able to say: ‘That star has a living world orbiting it.’ I think that’s very profound Read More ›

For whom is that a problem? Escience News attempts to set some limits to our uniqueness Frank said that the third big question–how long civilizations might survive–is still completely unknown. “The fact that humans have had rudimentary technology for roughly ten thousand years doesn’t really tell us if other societies would last that long or perhaps much longer,” he explained. But Frank and his coauthor, Woodruff Sullivan of the astronomy department and astrobiology program at the University of Washington, found they could eliminate that term altogether by simply expanding the question. “Rather than asking how many civilizations may exist now, we ask ‘Are we the only technological species that has ever arisen?” said Sullivan. “This shifted focus eliminates the uncertainty Read More ›

Riffing off Barry Arrington’s comment in Funny Shaped Rocks and the Design Inference, “It is amusing to watch some scientists insist on design inferences with respect to a relatively simple specification, while others refuse to countenance even the bare possibility of the same inference for a far more complex and intricate specification”: One thing that has always intrigued me is the way Why THEY Must Be Out There is supposed to be a question in science. There is no evidence that they are out there. The usual argument we hear is that it simply isn’t possible that we are alone. Well, excuse me, it is at least possible that we are alone. Each century They never call, They never write Read More ›

From Hugh Ross at Salvo: During my graduate school days at the University of Toronto (late 1960s) I took a short summer course, Advances in Planetary Physics, taught by astronomer Carl Sagan. Sagan was a rising star then and well on his way to becoming the science popularizer and communicator for which he later became famous. Most of the course and nearly all of the informal evening discussions focused on the possibility that extraterrestrial intelligent life existed and on the kinds of civilizations such beings would have established. In Sagan’s mind, there was absolutely no doubt that extraterrestrial intelligent beings (ETI) existed. Furthermore, he was convinced that on many planets in our galaxy ETIs had developed civilizations far more technically Read More ›

A new reason? ET is HAL, but not psychotic. From Aeon: From the evolution side, a number of futurists are predicting the singularity: a time when computers will soon become powerful enough to simulate human consciousness, or absorb it entirely. In parallel, some visionaries propose that any intelligent life we encounter in the rest of the Universe is more likely to be machine-based, rather than humanoid meat-bags such as ourselves. These ruminations offer a potential solution to the long-debated Fermi Paradox: the seeming absence of intelligent alien life swarming around us, despite the fact that such life seems possible. If machine intelligence is the inevitable end-point of both technology and biology, then perhaps the aliens are hyper-evolved machines so off-the-charts Read More ›

From Discover: Earth May Be a 1-in-700-Quintillion Kind of Place One of the most fundamental requirements for a planet to sustain life is to orbit in the “habitable zone” of a star — the “Goldilocks” region where the temperature is just right and liquid water can exist. Astronomers have, to this point, discovered around 30 exoplanets in the habitable zones of stars. Simply extrapolating that figure based on the known number of stars suggests that there should be about 50 billion such planets in the Milky Way alone. Probability seems to dictate that Earth-twins are out there somewhere. But according to Zackrisson, most planets in the universe shouldn’t look like Earth. His model indicates that Earth’s existence presents a mild Read More ›

It’s the latest new prejudice. From Quanta, we earn that the presence of oxygen does not show, as formerly thought, that a planet might have life. Oxygen can build up in environments hostile to life: As Domagal-Goldman, then a researcher at the University of Washington’s Virtual Planetary Laboratory (VPL), well knew, the gold standard in biosignature gases is oxygen. Not only is oxygen produced in abundance by Earth’s flora — and thus, possibly, other planets’ — but 50 years of conventional wisdom held that it could not be produced at detectable levels by geology or photochemistry alone, making it a forgery-proof signature of life. Oxygen filled the sky on Domagal-Goldman’s simulated world, however, not as a result of biological activity Read More ›

Further to “Is universe, complex as human brain, conscious?” (You know something’s up when people who discuss science at Forbes are even having this conversation), Pos-Darwinista writes to ask, re a recent astrobiology article: “Case for Gaian bottleneck?,” “Is this a case for removing the label ‘science’ from some efforts at astrobiology?” From Astrobiology: The Case for a Gaian Bottleneck: The Biology of Habitability Abstract: The prerequisites and ingredients for life seem to be abundantly available in the Universe. However, the Universe does not seem to be teeming with life. The most common explanation for this is a low probability for the emergence of life (an emergence bottleneck), notionally due to the intricacies of the molecular recipe. Here, we present Read More ›

Start the day right with something lite: From New Scientist: The signal – known as the “Wow! signal” after a note scribbled by astronomer Jerry Ehman, who detected it – came through at 1420 megahertz, corresponding to a wavelength of 21 centimetres. Searchers for extraterrestrial transmissions have long considered it an auspicious place to look, as it is one of the main frequencies at which atoms of hydrogen, the most common element in the universe, absorb and emit energy. What’s more, this frequency easily penetrates the atmosphere. But in the 40 years since, we’ve never heard anything like it again. Analysis of the signal ruled out a satellite, and a reflected signal from the Earth’s surface is unlikely because regulations Read More ›

The high-resolution image transmitted to Earth on Dec. 24 from the Long Range Reconnaissance Imager (LORRI) shows the dwarf planet’s icy surface. However, look a little closer and you may see a strange and dark snail-like object. Hey, They just gotta be out there!