Martian Meteorite NWA 7034 First From Mars' Crust; Could Help Explain Water's History On Mars

The search for water on our dusty red neighbor has been one of the pillars of our Martian research, which is currently being spearheaded by NASA's Curiosity rover mission. Some answers about Mars may lie here on Earth, as a new type of Martian meteorite believed to have come from Mars' crust has been discovered. Its age and origins may help explain the role water plays in Mars' geology. 

The meteorite, named Northwest Africa (NWA) 7034, is around 2.1 billion years old, weighs in around 320 grams, and is the first of its kind. There are over a 100 Martian meteorites in collections worldwide, and nearly all of them are generally classified as Shergotty, Nakhla, and Chassigny meteorites, or SNCs. NWA shares some characteristics with SNCs, but is thought to be the first meteorite to actually originate from the Martian crust. 

"The texture of the NWA meteorite is not like any of the SNC meteorites. It is made of cemented fragments of basalt, rock that forms from rapidly cooled lava, dominated with feldspar and pyroxene, most likely from volcanic activity. This composition is common for lunar samples, but not from other Martian meteorites. This unusual meteorite's chemistry suggests it came from the Martian crust," said co-author Andrew Steele from the Carnegie Institution's Geophysical Laboratory. 

NWA has also been found to contain more water than any of the SNCs previously discovered -  around 6,000 parts per million. This is around 10 times the amount of water found in SNCs, which are all younger, ranging from 200-400 million years old. NWA is from the beginning of Mars' last geological age known as the Amazonian and if scientists can figure out why more water is present in the older NWA meteorite than in the younger SNCs, they may be able to understand the role water has had in Mars' history.

"And of course those most recent times on Mars have witnessed a cold, dry planet with a thin atmosphere. A lot of people believe that early Mars, on the other hand, was a lot warmer and a lot wetter, and maybe even a harbour for life," explained lead researcher professor Carl Agee from the University of New Mexico to BBC. 

"So, what happened in between? When did this transformation to drier conditions occur? Well, NWA 7034, because of its greater age, may be able to address those questions." 

Read the full study published in Science Express.