Angelos Tsiaras, UCL
With more than 4,000 exoplanets – planets orbiting stars other than our sun – discovered so far, it may seem like we are on the cusp of finding out whether we are alone in the universe. Sadly though, we don’t know much about these planets – in most cases just their mass and their radius.
Understanding whether a planet could host life requires a lot more information. At the moment, one extremely important piece of information that is missing is the presence, composition, and structure of their atmospheres. Signs of atmospheric water, oxygen and methane would all be signs that a planet may support life.
Now we have for the first time managed to detect water vapour in the atmosphere of an exoplanet that is potentially habitable. Our results have been published in Nature Astronomy.
Continue reading How we detected water on a potentially habitable exoplanet for the first time
Thomas Moynihan, University of Oxford
It is 1950 and a group of scientists are walking to lunch against the majestic backdrop of the Rocky Mountains. They are about to have a conversation that will become a scientific legend. The scientists are at the Los Alamos Ranch School, the site for the Manhattan Project, where each of the group has lately played their part in ushering in the atomic age.
Continue reading The end of the world: a history of how a silent cosmos led humans to fear the worst
Few topics in science command as much attention as the discovery of extrasolar planets – those as-yet-unseen worlds, light years beyond our own Sun. In the quest to learn whether we are alone in the cosmos, astronomers are teasing out subtle wobbles and periodic dimmings of distant stars: telltale signs that a planet, much too faint to see directly in telescopes, is nevertheless present.
Continue reading In space, there really might be no place like home
Earth, our blue planet is an oasis in the vast, cold, and dark space. It is the only planet we know of that can support life. The fossil record tells us that life on Earth has lasted at least 3.5 billion years (the Earth is about 4.54 billion years old), with the oldest physical traces of life dating back 3.7 billion years. And, if some kind of disaster doesn’t intervene, our planet should continue to host life for at least another 1.75 billion years. Here are the 8 things that make life on Earth possible.
Continue reading 8 Things that make Life on Earth Possible
Scientists from the China National Space Administration (CNSA) has confirmed that the seedlings taken to the far side of the moon with Chang’e 4 lunar lander have started sprouting. Or to put it another way: this is the first time something has been grown on an astronomical body outside of the Earth! Now we have “moon plants”!
Continue reading Moon Plants: Another historic first by China’s Lunar Lander
In 1964, Russian astrophysicist Nikolai Kardashev (born April 25, 1932) defined three levels of civilizations, based on the order of magnitude of power available to them (known as the Kardashev scale):
Continue reading There is most probably no Kardashev Type III civilization in the Universe. Here’s why
What would convince you that aliens existed? The question came up recently at a conference on astrobiology, held at Stanford University in California. Several ideas were tossed around – unusual gases in a planet’s atmosphere, strange heat gradients on its surface. But none felt persuasive. Finally, one scientist offered the solution: a photograph. There was some laughter and a murmur of approval from the audience of researchers: yes, a photo of an alien would be convincing evidence, the holy grail of proof that we’re not alone.
Continue reading Proof of life: how would we recognise an alien if we saw one?
From blob-like jellyfish to rock-like lichens, our planet teems with such diversity of life that it is difficult to recognise some organisms as even being alive. That complexity hints at the challenge of searching for life as we don’t know it – the alien biology that might have taken hold on other planets, where conditions could be unlike anything we’ve seen before. ‘The Universe is a really big place. Chances are, if we can imagine it, it’s probably out there on a planet somewhere,’ said Morgan Cable, an astrochemist at the Jet Propulsion Laboratory in Pasadena, California. ‘The question is, will we be able to find it?’
Continue reading To find aliens, we must think of life as we don’t know it
According to a new study, microbes like those found in Earth’s deep ocean could potentially thrive in the underground ocean of Saturn’s icy moon Enceladus. Both molecular hydrogen (H2) and methane (CH4) already have been detected in the plume. Researchers have shown that Methanothermococcus okinawensis, a methanogenic archaeon first isolated from a deep-sea hydrothermal vent on the western Pacific Ocean, can produce methane under conditions known to exist on Enceladus.
Continue reading We May Have Already Detected Signs of Alien Microbes on Saturn’s Moon Enceladus
Are we alone in the universe? Or are there any other “living planets” other than Earth? Until 1992, we even don’t know if there are any other planets around the other stars or not. In 1992, two Swiss astrophysicists, Michel Mayor and Didier Queloz the first “exoplanet” (a planet orbiting another star than the Sun). Then discoveries continued. Especially after the launch of Kepler space telescope on March 7, 2009, which is a space observatory launched by NASA to discover Earth-size planets orbiting other stars, we quickly learned that our Solar System is not a rare phenomenon at all. As of November 2017, scientists have confirmed more than 3,500 exoplanets in more than 2,700 star systems. Now, the question is: are any of these planets (or the planets waiting to be discovered in the future) harbor life? If so, how we can find out? How to tell if a planet harbors life?
Currently, we have only one example: the Earth itself. Studying Earth and trying to figure out how we’d conclude the Earth harbors life from a distance (from space) can show us how to find out if a planet harbors life or not. Since 1997, NASA satellites have continuously observed all plant life at the surface of the land and ocean.
Continue reading Watch: How to tell if a planet harbors life?