New Evidence That Extraterrestrial Life May Exist

While the Phoenix Mars lander starts to scrape the surface in hopes of verifying that it's sitting on a swath of polar ice, new research here on Earth has raised yet more evidence that life can survive in the most extreme conditions.

On Mars, the Phoenix will ultimately analyze ice samples to determine if compounds necessary for life, or other evidence of life, are locked up there. Researchers have long suspected that conditions for life were once present on Mars, when free-flowing water might have incubated rudimentary life forms. Some have even guessed that life originated there, or somewhere else in the universe, and arrived on Earth via meteor.

The research on Earth, published in New Scientist, suggests that conditions would not have had to have been so friendly to support life.

Scientists studying the sediments of salty, acidic lakes in Western Australia and North Dakota have identified fossilized "hairy blobs" that "in close-up, look like something out of a 1950s B-movie."

No, they aren't fossils of extraterrestrial life, but they provide a framework for identifying life that thrived in some of the harshest conditions on Earth, and those same conditions may well have existed in some of the oceans on Mars.

The blobs are emblematic of what science fiction fans might expect from the search for extraterrestrial life. They've got a great name, but they aren't that impressive outside of a slide viewed by microscope. These hairy blobs, at less than 2 millimeters, would hardly make imposing villains in a thriller.

Here's how the research, by Kathleen Benison, a geologist at Central Michigan University, Mount Pleasant, was described by the university:

The team argues that each hair was in fact a separate microorganism because the hair fossils are made of disordered graphite which, unlike inorganic graphite, has irregular layers that suggest it was once a live organism.

Many of the hairs are coated with crystals of gypsum, a calcium sulphate mineral. This link with gypsum suggests that the microorganisms were fuelled by chemical interactions with sulphur in the acidic water - which helped the gypsum to form.

The team also found previously undescribed microorganisms in the lake water, which they say may be the cells that end up as fossilised hairs.

Conditions in acidic saline lakes such as those studied by the team are thought to be similar to those on ancient Mars. The many probes currently exploring the Red Planet have discovered that Martian seas and lakes, such as those once found at Meridiani Planum, were strikingly similar in terms of acidity, salinity and the minerals and sediments present.

Benison says the hairy blobs from the Permian halite seem well preserved. "This argues for long-term preservation of microfossils in halite elsewhere, perhaps even on Mars." Had the organisms lived on Mars, she says, the inorganic minerals surrounding them would have acted as protection from the ultraviolet radiation there.

In the past few years, scientists have found tantalizing evidence of a once-watery Mars, new Earth-like planets and evidence on Earth of strange creatures that live in the most extreme conditions imaginable, including strong acids, boiling heat, frigid cold and airless subterranean pockets.

In other words, the idea that life exists elsewhere has never seemed more plausible. If the thought excites you, you can volunteer your home computer's idle time in the search for intelligent life in outer space. If extraterrestrial civilizations are trying to contact us with radio signals, this mission is the best chance we have of hearing them.

University of California-Berkeley's eight-year-old SETI@home project uses the computing power of 320,000 individual desktop computers to crunch data. Now, with 500 times more data streaming in from an upgraded Arecibo telescope in Puerto Rico – enough data to fill the Library of Congress each year – scientists are seeking more volunteers willing to link their computers to the distributed super computer.

For information, see SETI@home.

If all this talk seems an odd fit for a green site, consider just how fragile the conditions are that support life as we know it on Earth. We can marvel at the way hairy blobs survive in extreme conditions, but we're wise if it inspires us to preserve the conditions on our home planet that make life so comfortable for the likes of us.

COMMENTS ()