- Life existed in the oceans 200 million years before oxygen appearerd on Earth
- India’s lunar mission finds evidence of water on the Moon
- Mars probe watches water-ice fade
- Spot makes strange dwarf planet even stranger
- Mice Levitated for Space Research
Life existed in the oceans 200 million years before oxygen appearerd on Earth
Life evolved at least 200 million years before oxygen began to build up in the atmosphere, a study has shown.
During this period in its history, known as the Archaean, the Earth was covered by a poisonous smog of methane, ammonia and other toxic gases.
Similar conditions exist today on Saturn's moon Titan. Life as we know it today could not have survived on the early Earth.
The new study involved an analysis of ancient preserved seabed rocks from South Africa dating back two to three billion years. US scientists at Rutgers University in New Brunswick, New Jersey, found chemical evidence of nitrogen cycles that could not have taken place without the presence of free oxygen. Nitrogen cycles relate to the way living things obtain and use nitrogen to produce complex organic molecules. Evidence of nitrogen cycles provides a ''fingerprint'' of life.
The researchers, Dr Linda Godfrey and Dr Paul Falkowski, concluded that organisms which produced oxygen as a by-product of photosynthesis must have evolved by around 2.5 billion years ago. Oxygen did not begin to enrich the atmosphere until at least 200 million years later.' sourceMy comment: Nice, huh! If life could survive back then, then there's probably life on Titan too! Awesome :)
India’s lunar mission finds evidence of water on the Moon
Dreams of establishing a manned Moon base could become reality within two decades after India’s first lunar mission found evidence of large quantities of water on its surface.
Data from Chandrayaan-1 also suggests that water is still being formed on the Moon. Scientists said the breakthrough — to be announced by Nasa at a press conference today — would change the face of lunar exploration.
The discovery is a significant boost for India in its space race against China. Dr Mylswamy Annadurai, the mission’s project director at the Indian Space Research Organisation in Bangalore, said: “It’s very satisfying.”
The search for water was one of the mission’s main objectives, but it was a surprise nonetheless, scientists said.The unmanned craft was equipped with Nasa’s Moon Mineralogy Mapper, designed specifically to search for water by picking up the electromagnetic radiation emitted by minerals. The M3 also made the unexpected discovery that water may still be forming on the surface of the Moon, according to scientists familiar with the mission.
Scientists are eagerly awaiting the results of two American unmanned lunar missions, which were both launched in June, that could also prove the existence of water on the Moon.
Early results from Nasa’s Lunar Reconnaissance Orbiter (LRO) recorded temperatures as low as -238C (minus 396.4F) in polar craters on the Moon, according to the journal Nature. That makes them the coldest recorded spots in the solar system, even colder than the surface of Pluto, and could mean that ice has been trapped for billions of years, the journal said. The LRO has also detected an abundance of hydrogen, thought to be a key indicator of ice, at the poles.source
My comment: Nice! I'm not exactly a fan of Moon colonization - so far it doesn't look like a lovely and interesting place, but it's definitely a good starting point for the longer journey. It's ideal for the production of spaceships, and so far it looks like it's totally green. Of course, that sounds little stupid, I admit, but it's a fact, for the moment, the Moon offers a good opportunity to experiment with spaceship production. If the experiments are under strict-control, so we don't mess the things beyond return, it should be ok. So the discovery of water, even if it's in molecular quantity is still great news. And what is more important- it gives good idea of how well-spread water could be in the universe. Yay for more habitable planets! Habitable by us, of course, there's nothing wrong with all the other planets to be inhabited by other species.
Mars probe watches water-ice fade
Science reporter, BBC N
Large deposits of nearly pure water-ice may lurk just below the Martian surface, much nearer the equator than previously thought, suggest new images.
The pictures acquired by a Nasa orbiter show white material exposed by fresh meteorite impacts fading over time - behaviour expected of ice on Mars.
An onboard instrument also detected the tell-tale chemical signature of water.
Researchers tell Science magazine that the observations suggest vast sheets of ice may reside in near-surface layers.
To date, exposed water-ice has only been seen at very high latitudes. The US space agency's (Nasa) recent Phoenix probe famously dug into water-ice at its "high Arctic" landing site.
The implication, even with the small set of examples scientists now have, is that broad deposits of ice sit just below the red top-soil of Mars.
"The volume of water is probably comparable to the volume that we would have in the Greenland ice sheet on the Earth - in the buried ice deposits that stretch from each pole to mid-latitudes."
The discoveries made by MRO are said to indicate that Mars had a more humid climate in the relatively recent past , within the last 10,000 years.
Scientists suspect much of this ice came out of the atmosphere. Water vapour in the atmosphere will diffuse through the particles of the soil until it gets to a certain depth where it then freezes."Based on the locations of these craters, we are able to say something about how much water was in the Martian atmosphere recently, and that turns out to be a lot more than is in the atmosphere today - maybe almost double what's in the atmosphere today."
CRISM team member Selby Cull, from Washington University in St Louis, said there was a "scientifically heart-breaking" consequence of the MRO discoveries.
This is the realisation that had Nasa's Viking-2 lander, which visited the Red Planet in 1976, dug a little deeper into the Martian soil, it would almost certainly have struck the water-ice MRO is now seeing at the base of impact craters.source
My comment: Heart-breaking indeed, because it would have changed the whole 30 years long idea that life is exclusive to Earth. And it could have stopped creationism from forming at all, right? Oh, well, still a wonderful news! Better late than never! And with water, one can obtain hydrogen and of course, oxygen - two very critical ingredients of a happy colonization of a planet. Nice, nice, nice :)
Spot makes strange dwarf planet even strangerA dwarf planet in our solar system, called Haumea, is known for its unusual shape and fast spin. Now astronomers have discovered another distinguishing feature: a dark red spot which appears to be richer in minerals and organic compounds than the surrounding icy surface.
Haumea, discovered in 2004, orbits the sun beyond Neptune, in a region known as the Kuiper Belt. It is classified as a dwarf planet — a celestial body that is big enough to have been rounded by its own gravity, but which has not cleared its orbital region of similar objects. The International Astronomical Union has designated four other bodies as dwarf planets: Ceres, Pluto, Eris and Makemake. Haumea is the fourth-largest dwarf planet.
Haumea is also the fastest-spinning large object in the solar system — one day on Haumea is equal to about 3.9 hours on Earth. This rapid rotation distorts Haumea, elongating it into a football-like shape.
Most of what we know about this object was determined from studying variations in its brightness, called a "light curve." And it is through examination of this light curve that scientists have found the dark spot.
Additionally, the light curve is not exactly the same shape in all wavelengths. Small but persistent differences indicate that the dark spot is slightly redder in visible light and slightly bluer at infrared wavelengths.
While the origin of the spot is unknown, possible interpretations of these measurements are that the spot is richer in minerals and organic compounds, or that it contains a higher fraction of crystalline ice. If the spot is a scar of a recent impact, then the spot material might resemble the composition of the impactor, perhaps mixed with material from the inner layers of Haumea.
My comment: I find it amazing that they managed to get all that info from the lightcurve, but then, it's a reflective lightcurve, it should be easier. Anyway, I'm so excited about this. I mean, this object is strange because of the spinning, but this "spot" is even cooler. I sincerely can't wait for the VLT observations. It's one to see the light curve, but something else to see it with your eyes. That's precisely why I so love astronomy - you see so many exciting objects. It could be only a dull rock, but until you see it and feel it - it's like a present in a box, it can be everything!
Mice Levitated for Space ResearchSeptember 11th, 2009 by Lin Edwards
(PhysOrg.com) -- Scientists have managed to levitate young mice in research carried out for NASA. Levitated mice may help research on bone density loss during long exposures to low gravity, such as in space travel and missions to other planets.
The scientists built a variable gravity simulator consisting of a superconducting magnet that could generate a magnetic field strong enough to levitate the water inside every cell in the mouse's body (water is weakly diamagnetic).
The mice were confined to a plastic cage, which had a base with holes to allow waste to be removed, and an open top to allow in air, food, water, and to allow the proceedings to be filmed.
The first subject to be levitated was just three weeks old. The tiny mouse was disturbed and disoriented and began to spin when it kicked out as though trying to find something to hold on to.
The next young mouse was mildly sedated before being levitated, and it was less agitated by the experience. The levitation experiments were repeated a number of times, and showed that the mice quickly adjusted to the conditions, even eating and drinking normally after a few hours of levitation. Even without sedation, the mice became quite comfortable floating in zero gravity.
The powerful magnetic field seemed to have no short term effects on the mice, and earlier studies on rats showed there were no ill effects even after 10 weeks' exposure to strong magnetic fields. sourceMy comment: This is nice, because it shows that low-gravity is ok with our psychology. I think I already published one study in which it was shown that embryos don't grow normally in low-gravity. The question is, what means normally? Because life in low-gravity is certainly different - if you will spend all of your life in such environment, normally may mean something different for you. So the main questions is are those changes dangerous or they are just optimal for your life!