There is some exciting news today regarding exoplanets – for the first time, multiple planets have been found orbiting within the habitable zone of their star, the region where temperatures can allow liquid water to exist on planets with rocky surfaces, like Earth. The news release was published this morning by the European Southern Observatory (ESO).
For decades, Jupiter’s moon Europa has been the focus of fascination and debate. Why? Because it has a global ocean – a deep, salty ocean similar to those on Earth, except that in Europa’s case it is always covered by a crust of ice. Speculation has grown that there could be life of some kind in that alien watery darkness, and now there is a new proposal for how to look for it – a tiny submarine!
The many orbiters, landers and rovers have, and continue to, send back an increasing wealth of information about Mars. Sometimes though, we are lucky enought to have a piece of Mars come to us instead. A bunch of Martian meteorites have been found over the years, in places like Antarctica. They offer a unique, hands-on peek into the geological history of the Red Planet. Now, one of them has yielded more clues to the possibility of life having started there, it was reported on June 11, 2013.
The outer solar system was once thought to be not much more than a frozen wasteland, at least in terms of the many moons orbiting the gas and ice giant planets. But with the intriguing discoveries made by robotic probes such as Voyager, Galileo and Cassini, we now know differently.
Not all that long ago, it was considered very unlikely that life could exist anywhere else in the solar system, apart from maybe Mars. A variety of robotic spacecraft missions, however, have changed scientists’ views; there are indeed a handful of other worlds in our own cosmic backyard which it is now known could potentially be habitable after all.
Venus has a reputation for being one of the most inhospitable places in the solar system, and deservedly so. Its thick carbon dioxide (and acidic) atmosphere has a crushing pressure similar to that in the deepest oceans on Earth and the scorching temperature on the surface is hot enough to melt lead. It’s like that everywhere on the planet, all the time. It has therefore been considered an extremely unlikely environment to support any kind of life. Even the toughest microbes here would find survival next to impossible. There is however a possibility, even if remote, that the upper atmosphere of this hellish world could be habitable, according to some scientists.