Featured Research

from universities, journals, and other organizations

Meteor Impacts: Life's Jump Starter?

Date:
August 10, 2005
Source:
Geological Society of America
Summary:
Meteor impacts are generally regarded as monstrous killers and one of the causes of mass extinctions throughout the history of life. But there is a chance the heavy bombardment of Earth by meteors during the planet's youth actually spurred early life on our planet, say Canadian geologists.

Ejecta block.
Credit: Courtesy of Gordon Osinski/Canadian Space Agency

Meteor impacts are generally regarded as monstrous killers and one ofthe causes of mass extinctions throughout the history of life. Butthere is a chance the heavy bombardment of Earth by meteors during theplanet's youth actually spurred early life on our planet, say Canadiangeologists.

A study of the Haughton Impact Crater on Devon Island, in theCanadian Arctic, has revealed some very life-friendly features atground zero. These include hydrothermal systems, blasted rocks that areeasier for microbes to inhabit, plus the cozy, protected basin createdby the crater itself. If true, impact craters could represent some ofthe best sites to look for signs of past or present life on Mars andother planets.

A presentation on the biological effects of impacts isscheduled for Monday, 8 August, at Earth System Processes 2, a meetingco-convened by the Geological Society of America and GeologicalAssociation of Canada this week in Calgary, Alberta, Canada.

The idea that meteor impacts could benefit or even createconditions suitable for the beginning of early life struck CanadianSpace Agency geologist Gordon Osinski while he and colleagues wereconducting a geological survey of the 24-kilometer (15-mile) diameterHaughton Crater. Along the rim of the crater they noticed what lookedlike fossilized hydrothermal pipes, a few meters in diameter.

"That set the bells ringing about possible biologicalimplications," said Osinski. Hydrothermal systems are thought by manypeople to be the favourable places for life to evolve."

Detailed mineralogical analyses have since revealed that whenthe Haughton meteor smacked into the icy ground 23 million years ago itcreated not only a crater, but fractured the ground in such a way as tocreate a system of steamy hydrothermal springs reaching temperatures of250 degrees C. The heat appears to have gradually dropped over a periodof tens of thousands of years, the researchers report.

Besides providing heat and cracking the ground, the impactalso created pore spaces in otherwise dense granitic rocks, givingmicrobes more access to the minerals and the surfaces inside the rocks- basically more real estate and more supplies.

The shocked rocks are also more translucent, which would bebeneficial to organisms that possessing with any photosyntheticcapabilities.

A crater shape itself also might serve as a protectiveenvironment, says Osinski. As such, impact craters are also good placesto store evidence of past life. On Earth many craters fill with waterand become lakes. Lakes accumulate sediments, the layers of which are ageological archive of the time after the crater formed. The HaughtonImpact crater, for instance, contains the only Miocene-age sediments inthe entire Canadian Arctic.

"One of the most interesting aspects of the Haughton ImpactCrater is that it's in a polar desert," said Osinski. The dry, frigidweather makes for a barren landscape that's easy to study, he said. Thesame features make it one of the more Mars-like places on Earth.

"Most people put impacts with mass extinctions," said Osinski."What we're trying to say is that following the impact, the impactsites are actually more favorable to life than the surroundingterrain."

It's interesting to note, says Osinski, that on Earth theheaviest meteor bombardment of the planet happened at about the sametime as life is believed to have started: around 3.8 billion years ago.Impact craters of that age were long ago erased on Earth by erosion,volcanic resurfacing and plate tectonics.

But other planets and moons - including Mars - still bear thecosmic scars of that early debris-clogged period in the solar system.It may be possible, therefore, that the best places to look for atleast fossil evidence of life on Mars is inside those very samecraters, he said.

"What we're doing is trying to narrow down the search area," said Osinski.



Story Source:

The above story is based on materials provided by Geological Society of America. Note: Materials may be edited for content and length.


Cite This Page:

Geological Society of America. "Meteor Impacts: Life's Jump Starter?." ScienceDaily. ScienceDaily, 10 August 2005. <www.sciencedaily.com/releases/2005/08/050809065655.htm>.
Geological Society of America. (2005, August 10). Meteor Impacts: Life's Jump Starter?. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2005/08/050809065655.htm
Geological Society of America. "Meteor Impacts: Life's Jump Starter?." ScienceDaily. www.sciencedaily.com/releases/2005/08/050809065655.htm (accessed September 20, 2014).

Share This



More Earth & Climate News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Climate Change Rally Held in India Ahead of UN Summit

Climate Change Rally Held in India Ahead of UN Summit

AFP (Sep. 20, 2014) Some 125 world leaders are expected to commit to action on climate change at a UN summit Tuesday called to inject momentum in struggling efforts to tackle global warming. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
New Music With Recycled Instruments at Colombia Fest

New Music With Recycled Instruments at Colombia Fest

AFP (Sep. 19, 2014) Jars, bottles, caps and even a pizza box, recovered from the trash, were the elements used by four musical groups at the "RSFEST2014 Sonorities Recycling Festival", in Colombian city of Cali. Duration: 00:49 Video provided by AFP
Powered by NewsLook.com
Raw: Wildfires in CA Burn Forest Asunder

Raw: Wildfires in CA Burn Forest Asunder

AP (Sep. 18, 2014) An out-of-control Northern California wildfire has nearly 2,800 people from their homes as it continues to grow, authorities said Thursday. Authorities said a man has been arrested on suspicion of arson for starting the fire on Saturday. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins