Geological landforms indicate 'recent' warm weather on Mars
June 29, 2009
Retrogressive scarps with cuspate niches, long branching spurs and associated fluvial-like tributary channels. Credit:NASA/JPL/UofA
(PhysOrg.com) -- New research led by a UK scientist indicates that Mars had significantly warmer weather in its recent past than previously thought. The research, funded by the UK’s Science and Technology Facilities Council (STFC) and published in Earth and Planetary Science Letters, is good news in our quest for life on Mars, as the shorter the time period since the last warm weather on the planet, the better the chance that any organisms that may have lived in warmer times are still alive under the planet’s surface.
Dr Matthew Balme, from The Open University, made the new discovery by studying detailed images of equatorial landforms that formed by melting of ice-rich soils. His work indicates that the Martian surface experienced “freeze thaw” cycles as recently as 2 million years ago, and that Mars has not been locked in permafrost conditions for billions of years as had been previously thought.
The high resolution images, which show a variety of interesting landforms, were taken with NASA’s HiRISE (High Resolution Imaging science Experiment) which is onboard the Mars Reconnaissance Orbiter (MRO) mission.
Dr Matthew Balme said, “The features of this terrain were previously interpreted to be the result of volcanic processes. The amazingly detailed images from HiRISE show that the features are instead caused by the expansion and contraction of ice, and by thawing of ice-rich ground. This all suggests a very different climate to what we see today.”
All of the landforms observed are in an outflow channel, thought to have been active as recently as 2 -8 million years ago. Since the landforms exist within, and cut across, the pre-existing features of the channel, this suggests that they too were created within this timeframe.
The pictures show polygonally patterned surfaces, branched channels, blocky debris and mound/cone structures. All of these features are similar to landforms on Earth typical of areas where permafrost terrain is melting.
Dr Balme said, “These observations demonstrate not only that there was ice near the Martian equator in the last few million years, but also that the ice melted to form liquid water and then refroze. And this probably happened for many cycles. Given that liquid water seems to be essential for life, these kinds of environments could be a great place to look for evidence of past life on Mars.”
Professor Keith Mason, CEO of the Science and Technology Facilities Council (STFC), said, “This new research has revealed more about Mars and provided fascinating evidence of geological process similar to Earth. The history of our neighbouring planet, and the question of whether it has ever sustained life, has long fascinated man. Understanding current processes on the surface of Mars and the past and present role of climate improves our knowledge of the planet’s history and thus the chances of one day detecting evidence for past or present life. UK scientists are involved in a number of different Mars studies, which are helping to paint a full picture of this mysterious planet.”
Provided by Science and Technology Facilities Council (news : web)
Oct 26, 2007 |
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Haven't you figured out yet that numbers in modern "science" are entirely arbitrary and just made up out of whole cloth?
We should be looking for ceramic material in the shape of spark plug insulators.
Ha! ...don't you realize any "advanced civilization" would not have used internal combustion engines? :-)
Seriously, though... I always laugh at reports of SETI searching the stars for transmissions that would suggest the invention of electronic communications analogous to our own.... as if that would suggest intelligent life! Putting aside the IQ suggested by the "content", realize that we've already undergone generations of evolution in encoding schemes: morse code, AM, FM, TV, DTV and the many specialized encodings, all in a matter of a 'blink' in time as far as evolution goes. The most advanced forms of communications today involve spread spectrum techniques base on pseudo random encodings in time and spectrum.... they look like noise! We should not be looking for "repetitive" signals, because they are old fashioned and wasteful in energy and spectrum. Modern signals today look like "noise" with no discernable structure unless you know the encryption key. ....and we have already seen lots of "noise" sources out there. The question is: can we decipher the key?
Again: our ignoranced is only exceeded by our lack of humility. Feel the awe... enjoy the discovery of our own ignorance!
Good insight. As a person who is keenly interested in Cryptography, one would recognize that we are extremely unlikely to detect "stray" transmissions from an intelligent race, even if such actually exist. Only if they were intentionally trying not to be cryptic would we be able to detect a signal, and even then, only if looking at exactly the right direction at exactly the right time.
We could not actually detect and "decode" a coded transmission from another race because, as you stated, any such transmission would likely by encrypted (and probably also compressed.) Thus any such transmission would appear entirely random with absolutely no way of decoding it. Not to mention, an alien race may use completely different concepts of language and symbology. Most of our english text comes from just 52 alphabet characters, upper and lower case, plus 10 digits and a few punctuation and grouping symbols, a.k.a. "ascii". But much like other human civilizations, an alien race may use hieroglyphics or some other form of written language, and thus have thousands upon thousands of "basic" symbols. Thier written language, and consequently "computer text language" may in fact be incredibly hard to decode into our language, and certainly many words and phrases would have no translation whatsoever, as we have Oak trees and bears, but there wouldn't be expected to be Oaks or bears on another planet, etc.
An alien race may use coding systems much different than what we would use, and may use computer processors very different from what we would expect. We tend to use processors, and therefore common data objects, with a power of 2 number of transistors, but this is largely arbitrary. The aliens may consider 10 bits as a "byte" and may have 40 bit processors, not 32, and etc. Their language(s) may encode "planet" as a single character represented in computers and radio transmissions by binary "0000000001", whereas in english we need 6 bytes (42 bits) to spell "planet".
Meh....