Building blocks of life formed on Mars

December 11, 2007
Mars
Mars. Credit: NASA

Organic compounds contain carbon and hydrogen and form the building blocks of all life on Earth. By analyzing organic material and minerals in the Martian meteorite Allan Hills 84001, scientists at the Carnegie Institution's Geophysical Laboratory have shown for the first time that building blocks of life formed on Mars early in its history. Previously, scientists have thought that organic material in ALH 84001 was brought to Mars by meteorite impacts or more speculatively originated from ancient Martian microbes.

The Carnegie-led team made a comprehensive study of the ALH 84001 meteorite and compared the results with data from related rocks found on Svalbard, Norway. The Svalbard samples occur in volcanoes that erupted in a freezing Arctic climate about 1 million years ago—possibly mimicking conditions on early Mars.

“Organic material occurs within tiny spheres of carbonate minerals in both the Martian and Earth rocks,” explained Andrew Steele, lead author of the study. “We found that the organic material is closely associated with the iron oxide mineral magnetite, which is the key to understanding how these compounds formed.”

The organic material in the rocks from Svalbard formed when volcanoes erupted under freezing conditions. During cooling, magnetite acted as a catalyst to form organic compounds from fluids rich in carbon dioxide (CO2) and water (H2O). This event occurred under conditions where no forms of life are likely to exist. The similar association of carbonate, magnetite and organic material in the Martian meteorite ALH 84001 is very compelling and shows that the organic material did not originate from Martian life forms but formed directly from chemical reactions within the rock. This is the first study to show that Mars is capable of forming organic compounds at all.

The organic material in the Allan Hills meteorite may have formed during two different events. The first, similar to the Svalbard samples, was during rapid cooling of fluids on Mars. A second event produced organic material from carbonate minerals during impact ejection of ALH 84001 from Mars.

“The results of this study show that volcanic activity in a freezing climate can produce organic compounds,” remarked co-author Hans E.F. Amundsen from Earth and Planetary Exploration Services. “This implies that building blocks of life can form on cold rocky planets throughout the Universe.”

“Our finding sets the stage for the Mars Science Laboratory (MSL) mission in 2009,” remarked Steele, who is a member of the Sample Analysis on Mars (SAM) instrument team onboard MSL. “We now know that Mars can produce organic compounds. Part of the mission's goal is to identify organic compounds, their sources, and to detect molecules relevant to life. We know that they are there. We just have to find them.”

The research is published in Meteoritics & Planetary Science: meteoritics.org/index.htm

Source: Carnegie Institution

Explore further: Science on the surface of a comet

Related Stories

Science on the surface of a comet

July 31, 2015

Complex molecules that could be key building blocks of life, the daily rise and fall of temperature, and an assessment of the surface properties and internal structure of the comet are just some of the highlights of the first ...

Recommended for you

Image: Hubble sees a dying star's final moments

July 31, 2015

A dying star's final moments are captured in this image from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star's demise is still quite ...

Earth flyby of 'space peanut' captured in new video

July 31, 2015

NASA scientists have used two giant, Earth-based radio telescopes to bounce radar signals off a passing asteroid and produce images of the peanut-shaped body as it approached close to Earth this past weekend.

Exoplanets 20/20: Looking back to the future

July 31, 2015

Geoff Marcy remembers the hair standing up on the back of his neck. Paul Butler remembers being dead tired. The two men had just made history: the first confirmation of a planet orbiting another star.

Dense star clusters shown to be binary black hole factories

July 29, 2015

The coalescence of two black holes—a very violent and exotic event—is one of the most sought-after observations of modern astronomy. But, as these mergers emit no light of any kind, finding such elusive events has been ...

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Nikola
3.5 / 5 (2) Dec 11, 2007
I think that we will find, as we continue to explore the Universe, that life is abundant. Look at the Hubble Ultra Deep Field image. No life in any of those 50,000 galaxies? I don't think so. Just my opinion though.
Tomkaten
3.7 / 5 (3) Dec 11, 2007
Sorry, but we don't explore the Universe. We've barely begun exploring our closest planetary neighbor. Finding germs and bacteria there will bring about an amazing revelation for mankind.

But when it comes to intelligent life, allow me to have certain reservations. The Universe is so vast, that it's silly to assume we're going to find it any time soon, if ever... It's just the way it is. Interstellar travel is just a myth right now.
It may sound funny, but IMO the most pressing disovery that would enable us to travel to other stars would be to find a way to prolong human existence indefinitely. While that would do wonders for space explorations, it would definitely bring about other insurmountable problems.
earls
1 / 5 (2) Dec 11, 2007
Non-sense.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.