THE GIST Early Earth may have had too much water for life to take hold. Conditions for life may have been better on Mars, which had dry spots. Cycles of water and drying may have been needed to give the molecular building blocks for life a chemical toehold. Given the same raw materials, Mars would have been a better host for life to arise than Earth, which some scientists believe was too flooded for the chemistry of life to gain a toehold. Without at least occasional dry land, the chemistry needed to get life started doesn’t work very well because the molecules to support genetics, such as RNA, are chemically unstable in many ways, particularly in water. PHOTOS: Weirdest Mars Craters That raises a problem, ... Continue reading →
Scientists have found two interstellar clouds of original gas, which -- unlike everything else in the universe -- has never mingled with elements forged later in stars. The existence of pristine gas that formed minutes after the Big Bang explosion some 13.7 billion years ago, had been predicted, but never before observed. The clouds, which are located about 12 billion light-years from Earth within the constellations Ursa Major and Leo, were found serendipitously during an ongoing study to characterize gas in distant galaxies. In analyzing the light coming from quasars (active nuclei of distant galaxies), astronomers realized the rays had passed through gas that contained only hydrogen and deuterium, elements that formed minutes after the Big Bang. The surprise was that the clouds contained nothing ... Continue reading →
It has been 15 years since Russia has attempted to send a spacecraft to another planet, but that dry spell is due to end next week with the launch of an ambitious mission to return soil samples from the Martian moon Phobos. The project, called Phobos-Grunt ("grunt" is Russian for "soil") also includes a small Chinese spacecraft called Yinghuo 1 that is designed to orbit Mars, as well as an astrobiology experiment from the California-based Planetary Society which will test a theory that living organisms could have arrived on Earth inside meteorites. "It's a very challenging mission. I know the Russians have gone to a lot of trouble to ensure success," Planetary Society projects director Bruce Betts told Discovery News. Russia hasn't attempted an interplanetary ... Continue reading →