TECHNOLOGY FOR CHANGE

Three Reasons NASA Won't Find Life on Other Planets

R. Colin Johnson | Date: 01-12-10 | Comments

The National Aeronautics and Space Administration (NASA) recently reported three new techniques it is using to detect life on other planets, but unfortunately none will be able to provide unequivocal proof that life exists elsewhere.

Three recent NASA reports detailed that its Kepler space telescope discovered five new exoplanets (planets outside our solar system), that its Deep Impact mission has been able to recognize sun glints off planetary oceans, and a new experiment for the Sample Analysis at Mars (SAM) instrument which will search for life on Mars in 2012.

Kepler Finds Five

The Kepler space telescope was launched in 2009 with a mission to continuously and simultaneously observe more than 150,000 star systems in the attempt to find Earth-size planets. The unique ability of its "photometer" instrument is that it can spot minor dips in brightness as exoplanets traverse in front of a distant star.

So far Kepler has analyzed the signatures of hundreds of possible planets, but ground-based telescopes have only been able to confirm five sightings as being caused by new exoplanets, all of which are hotter than molten lava (2,200 to 3,000 degrees Fahrenheit) and about the size of Jupiter. Earth-size planets at a temperature where liquid water could exist, unfortunately, will require three years of observations, putting off any Earth-like planetary sightings until 2012.

Even if Kepler does sight Earth-size planets at the right temperature, it will not be able to confirm that liquid water exists on the surface nor any other evidence of life existing there.

Deep Impact Repurposed

To detect liquids on a distant planet's surface, NASA's Deep Impact spacecraft has recently been repurposed from its original mission (to study the comet Tempel 1) to watching for exoplanet sun glints--bright flashes of light that serve as beacons signaling large bodies of liquid on distant planets.

Called the Extrasolar Planet Observations and Characterization (EPOCh) mission, NASA recently proved the concept by pointing Deep Impact's instruments back toward Earth where it was able to easily discern sun glints off its oceans and some inland lakes.

Unfortunately, even if Deep Impact is trained on the exoplanets identified in 2012 by Kepler, it will only be able to verify bodies of liquid on the surface, not specifically water, making its observations inconclusive regarding the discovery of life.

Life Detection on Mars

NASA's latest rover will land on Mars in 2012. Called Sample Analysis at Mars, SAM is a combination of a gas chromatograph, a quadruple mass spectrometer and a tunable laser spectrometer.

A new experiment recently added to SAM will analyze large carbon-based molecules--if any are found--using a combination of heat and a chemical reagent that identifies whether the molecules could have derived from former organic molecules like carbohydrates, lipids, proteins and nucleic acids.

Unfortunately, SAM's new experiment will not provide unequivocal proof, but only indicate the possibility of former life forms on Mars.