Share

Secrets of Ancient Mars Revealed in Meteorite

Mike Wall
Published: November 21, 2013

A meteorite found last year in the Sahara Desert is likely the first recognized piece of ancient Martian crust, a new study reports.

The Mars meteorite NWA 7533 is 4.4 billion years old and contains evidence of long-ago asteroid strikes, suggesting that the rock came from the Red Planet’s ancient and cratered southern highlands, researchers said.

“We finally have a sample of the Martian highlands, that portion of Mars that holds all the secrets to Mars’ birth and early development,” lead author Munir Humayun of Florida State University told SPACE.com via email. [Photos: Amazing Meteorites from Mars]

“It’s the part of Mars’ history where the oceans and atmosphere developed, and where life would have developed if it ever did on Mars,” Humayun added. “I will liken this to opening a treasure chest — it may take a while before we find the best treasures, but treasures aplenty lurk in this meteorite.”

Luc Labenne

Sawn surface of the Mars meteorite NWA 7533 showing both light and dark clasts in grey matrix.

Humayun and his colleagues subjected NWA (short for northwest Africa, where the rock was found) 7533 to a series of analyses. The researchers determined the meteorite’s age, for example, by determining that crystals within it called zircons formed about 4.4 billion years ago.

“This date is about 100 million years after the first dust condensed in the solar system,” Humayun said in a statement. “We now know that Mars had a crust within the first 100 million years of the start of planet-building, and that Mars’ crust formed concurrently with the oldest crusts on Earth and the moon.”

The team also found high concentrations of normally rare elements such as nickel, osmium and iridium in NWA 7533, indicating that the rock formed in a region that was pummeled by chondritic meteors, which are relatively enriched in these materials.

Further, after measuring the abundances of certain elements within the meteorite, Humayun and his team were able to calculate a thickness for the Red Planet’s crust.

“The amount of melting on Mars was low, sufficient to accumulate a 50-kilometer-thickness [31 miles] crust, but Mars evidently escaped the giant impact-style melting that affected the Earth and moon,” Humayun told SPACE.com. (Most scientists think the moon formed from material blasted into space when a planet-size body crashed into Earth more than 4 billion years ago.)

“This is the first reliable geochemical estimate of the thickness of Mars’ crust, and it agrees with geophysical estimates from gravity and topography,” he added.

Though researchers believe ancient Mars was relatively warm and wet, the team found no hydrous silicate minerals — which form in the presence of liquid water — within NWA 7533. Scientists will likely unearth more such puzzling details as they study the meteorite further, Humayun said.

“I expect more surprises as we dig deeper into our Martian treasure chest — some we will understand, and others may continue to befuddle us for a while to come,” he said.

Follow SPACE.com on Twitter @Spacedotcom. We’re also on Facebook & Google+. Originally published on SPACE.com.

7 Biggest Mysteries of Mars

Fallen Stars: A Gallery of Famous Meteorites

Mars Myths & Misconceptions: Quiz

Copyright 2013 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

MORE: NASA Video Shows Mars 4 Billion Years Ago

Mountain Winds at Gale Crater

Mountain Winds at Gale Crater

This graphic shows the pattern of winds predicted to be swirling around and inside Gale Crater, which is where NASA's Curiosity rover landed on Mars. Modeling the winds gives scientists a context for the data from Curiosity's Rover Environmental Monitoring Station. Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS

  • Mountain Winds at Gale Crater
  • Five Bites into Mars
  • Self-Portrait of the Curiosity Rover
  • Self-Portrait of Curiosity Rover (Bottom View)
  • Wind-Blown Martian Sand
  • Rock Et-Then Near Curiosity
  • Rock Burwash

Featured Blogs

Cristobal Headed Towards Iceland; 98L Moving Inland Over Texas

By Dr. Jeff Masters
August 28, 2014

Hurricane Cristobal continues to churn northeastwards over the Atlantic towards Iceland. Satellite loops show that Cristobal has its most impressive appearance of its lifetime, with a large symmetric area of heavy thunderstorms. Cristobal will merge with a frontal zone on Friday and transition to a powerful extratropical storm that will likely bring tropical storm-force winds and heavy rain to Iceland on Sunday night.

Record Warmth in Northeastern Canada, Record Cold in Northern Ireland

By Christopher C. Burt
August 26, 2014

August has continued the July pattern of anomalously warm weather in Canada’s far eastern regions with a new all-time record high of 22.7°C (72.9°F) measured at Resolution Island, Nunavut on August 23rd. In contrast, Northern Ireland observed its coldest August temperature on record the morning of August 24th with a -1.9°C (28.6°F) reading.

Live Blog: Tracking Hurricane Arthur as it Approaches North Carolina Coast

By Shaun Tanner
July 3, 2014

This is a live blog set up to provide the latest coverage on Hurricane Arthur as it threatens the North Carolina Coast. Check back often to see what the latest is with Arthur. The most recent updates are at the top.

Tropical Terminology

By Stu Ostro
June 30, 2014

Here is some basic, fundamental terminology related to tropical cyclones. Rather than a comprehensive and/or technical glossary, this represents the essence of the meaning & importance of some key, frequently used terms.

2013-14 - An Interesting Winter From A to Z

By Tom Niziol
May 15, 2014

It was a very interesting winter across a good part of the nation from the Rockies through the Plains to the Northeast. Let's break down the most significant winter storms on a month by month basis.

What the 5th IPCC Assessment Doesn't Include

By Angela Fritz
September 27, 2013

Melting permafrost has the potential to release an additional 1.5 trillion tons of carbon into the atmosphere, and could increase our global average temperature by 1.5°F in addition to our day-to-day human emissions. However, this effect is not included in the IPCC report issued Friday morning, which means the estimates of how Earth's climate will change are likely on the conservative side.