So J. do you think that other forms of life are out there? How long do you think before we'll actually know?
Well, if by other forms of life you mean microbial life, then yes. We have to look no further than the solar system to find it. We’ve got several places within The Solar System which can harbour microbial life. Places like Mars, Enceladus, Titan and Europa can easily support microbial life.
Titan, a moon of Saturn, is one of the most interesting places in The Solar System. It’s the only moon with a thick atmosphere and its chemistry is very similar to that of prebiotic-Earth. It even has liquid hydrocarbon lakes! Nearly 20 percent of the surface is covered with lakes of methane and ethane. Titan has all the right ingredients to start life.
http://www.universetoday.com/75271/titan%E2%80%99s-atmosphere-could-produce-building-blocks-of-life/ We only have to find out if it has. Any life that may arise on Titan will be different from Earth. It would probably be some methane-based life form. We’ve seen some interesting things going on Titan; hydrogen and acetylene are being depleted at the surface of Titan. One solid explanation for the phenomena is that methane-based life forms are eating them at the surface [http://adsabs.harvard.edu/abs/2005Icar..178..274M ]. But it isn’t the only explanation. We can’t be absolutely certain that this is being caused by life until we’ve ruled out all of the other possible explanations.
There’s intriguing stuff going on Mars as well. There is – I forgot how many tons exactly, but the number is in hundreds – tons of excess methane in the Martian atmosphere. Methane should only last for two years or so in the Martian atmosphere. There is a seasonal change in the levels of methane, the highest concentrations are seen during the warmest months and lowest concentrations are seen during the colder months. So, there’s something at the surface of Mars that’s replenishing the methane on Mars, there are two possible explanations for this. One is that there a geological process, such as volcanic out gassing, releasing the methane from the core. The second explanation is a bit more exciting than the first one; a biological process going on at the surface of Mars is replenishing the methane, like methanogens. The area with the highest concentrations of methane is a volcanic region called Tharsis. It is possible that there could be some geological activity going on which marks the presence of hot springs and hydrothermal vents, these are the places that we find methnogens on here on Earth. So, it could be both or it could just be one. We have to study this further to find out what it is.
We can’t claim that we have found life on Mars and Titan until we actually go there and get some samples. But what we’re finding out through these secondary means is very exciting.
Back on Earth, we’re discovering life where it shouldn’t be. Extremophiles are redefining places we call inhabitable. We’re finding isolated ecospheres where life is thriving, like this guy
http://en.wikipedia.org/wiki/Desulforudis_audaxviator. We’re finding that life isn’t as fragile as we thought. It’s very resilient once it gets going. The exoplanet count is above 500. There are more than 700 exoplanets discovered by the Kepler mission alone, but they’re not added to the total count of the planets because the team is double checking the data. That gives us a lot of different ecospheres to choose from and I think it’s quite likely that one of them has microbial life.
Topic: How can we comprehend the number of galaxies?