Language Selection

English French German Italian Portuguese Spanish

Has Huygens found life on Titan?

Filed under
Sci/Tech

IF LIFE exists on Titan, Saturn's biggest moon, we could soon know about it - as long as it's the methane-spewing variety. The chemical signature of microbial life could be hidden in readings taken by the European Space Agency's Huygens probe when it landed on Titan in January.

Titan's atmosphere is about 5 per cent methane, and Chris McKay of NASA's Ames Research Center in Moffet Field, California, thinks that some of it could be coming from methanogens, or methane-producing microbes. Now he and Heather Smith of the International Space University in Strasbourg, France, have worked out the likely diet of such organisms on Titan.

They think the microbes would breathe hydrogen rather than oxygen, and eat organic molecules drifting down from the upper atmosphere. They considered three available substances: acetylene, ethane and more complex organic gunk known as tholins. Ethane and tholins turn out to provide little more than the minimum energy requirements of methanogenic bacteria on Earth. The more tempting high-calorie option is acetylene, yielding six times as much energy per mole as either ethane or tholins.

McKay and Smith calculate that if methanogens are thriving on Titan, their breathing would deplete hydrogen levels near the surface to one-thousandth that of the rest of the atmosphere. Detecting this difference would be striking evidence for life, because no known non-biological process on Titan could affect hydrogen concentrations as much.

One hope for testing their idea rests with the data from an instrument on Huygens called the GCMS, which recorded Titan's chemical make-up as the probe descended. It will take time to analyse the raw data, partly because hydrogen's signal will have to be separated from those of other molecules. "Eventually, I hope, we will have numbers for at least upper limits for hydrogen," says Hasso Niemann of Goddard Space Flight Center in Maryland, principal investigator of the GCMS.

Acetylene could be easier to analyse, McKay says, and it too might betray life. "I would guess that there would be a similar fall-off of acetylene if the microbes are eating it." The work is to be published in the journal Icarus.

By Stephen Battersby
NewScientistSpace.com.

More in Tux Machines

This is the world’s most stunning new Android phone – and it’ll only cost you $5,000

While there’s no question that the iPhone 6 and iPhone 6 Plus are beautiful smartphones, some might argue that Apple’s 2012 iPhone 5 and last year’s iPhone 5s feature an overall look that is more sleek and sophisticated. Now, imagine that sophisticated design was given harder lines, darker tones and a 5-inch full HD display, and it was built out of titanium and 18k gold instead of aluminum. Read more

Ubuntu GNOME 15.04 Alpha 1 Prepares for GNOME 3.14, Go Forth and Test

The Ubuntu GNOME developers have released the first version of the 15.04 branch for their Linux distribution and it looks like this operating system is also going through some interesting changes, just like Ubuntu, although not on the same scale. Read more

FSF's High Priority Project List Now Has A Committee

The Free Software Foundation has now built up a committee to review their "High Priority Projects" list and they're looking for more feedback from the community. Nearly ten years ago is when the Free Software Foundation began listing what they viewed as the High Priority Free Software Projects in a list. This list has over time contained some definite high-priority projects related to freeing Java and Adobe PDF support and open graphics drivers to some more obscure projects of high priority like a free version of Oracle Forms, a replacement to OpenDWG libraries for CAD files, automatic transcription software, etc. I've personally called out many of the FSF HPP for what they're worth with my thoughts over the years. Read more

Latest Calibre eBook Reader and Converter Now Support Latest Kobo Firmware

The Calibre eBook reader, editor, and library management software has just reached version 2.13 and the developer has added an important driver and made quite a few fixes and improvements. Read more