First, New Scientist regarding a discovery off the coast of Taiwan that indicates yet another hostile environment that supports life:

Microbes discovered by a lake of liquid carbon dioxide under the sea off Taiwan could help us locate life on Mars, researchers say.

Japanese and German researchers have found billions of bacteria and other tiny organisms living in a layer of sediment which traps the CO₂ under the seabed. Their survival in such a hostile natural environment suggests that something similar could be happening on other planets.

If water and CO₂ are present below the surface in polar environments, says Fumio Inagaki at the Japan Agency for Marine-Earth Science and Technology in Yokosuka, “I expect that life signatures utilising chemical materials and CO₂ for growth might be found.”

And from Carl Zimmer comes the explanation of “[h]ow five big questions about biology on our planet are shaping the search for life on other worlds”:

There are many strange landscapes in the solar system, but perhaps none stranger than that of Titan, Saturn’s largest moon. Deserts blanket Titan for hundreds of miles, rippling with wind-sculpted dunes that rise more than 300 ft. Images taken by the Cassini spacecraft over the past two years also reveal riverbeds sculpted by liquid methane, canyons, and what appear to be a volcano and a shoreline. When Cassini dropped the Huygens probe onto Titan’s surface in 2005, the 701-pound craft landed in a substance with the consistency of wet sand. Shrouding it all is a smoggy, orange-hued atmosphere 10 times thicker than Earth’s and made up of complex organic molecules.

“Titan is so cool,” says Peter Ward, who leads NASA-funded astrobiology research at the University of Washington. “Titan is the most exciting place in the solar system astrobiologically. It has the most exciting chemistry set in our solar system by far. If there’s life on Titan, it’s alien life–really alien life.”

But finding microorganisms on Titan–or anywhere in the universe–is no easy task. Titan has carbon-based molecules, for example, which is one of the necessary ingredients for life as we know it. But the recipe may be different there than it is here on Earth.

“Methane plays the same meteorological role on Titan as water does on Earth. So what would life look like if it drank a glass of methane in the morning, rather than a glass of Florida orange juice?” asks molecular biologist Steven Benner, a distinguished fellow at the Foundation for Applied Molecular Evolution. No one knows, but it is one of many questions intriguing astrobiologists.

While the article is quite long, it’s well worth your time.

Remember a few decades ago when the very topic of alien life caused laughter and scorn, and no respectable scientist would even mention the possibility?  Now, only the ignorant would deny there is probably life out there, and scientists the world over agree wholeheartedly that we are not alone.

My, how times change.