An analysis of a meteorite found in the Sahara Desert reveals the existence of water on Mars 4.4 billion years ago, scientists say.
The mineral composition of the Martian meteorite NWA 7533, discovered in 201
The 84-gram meteorite, named in part for its landing site in northwest Africa, was part of a celestial rock that disintegrated as it entered the Earth’s atmosphere.
It is already well known to planetary scientists that there has been water on the Red Planet for at least 3.7 billion years.
But given the previously established age of NWA 7533 and its newly discovered mineral composition, researchers have now concluded that water was present for another 700,000 years before this estimate.
DIFFERENT TYPES OF COSMIC ROCKS
An asteroid is a large piece of rock left over from collisions or the early solar system. Most are located between Mars and Jupiter in the Main Belt.
A comet is a rock covered with ice, methane and other compounds. Their orbits take them much farther from the solar system.
A meteor is what astronomers call lightning in the atmosphere when debris burns.
This debris itself is known as a meteoroid. Most are so small that they evaporate into the atmosphere.
If any of this meteoroid reaches Earth, it is called a meteorite.
Meteors, meteoroids and meteorites usually originate from asteroids and comets.
If there was water on Mars earlier than expected, this suggests that water is probably a natural by-product of some process at the beginning of the formation of the planet.
This can help answer the question of where water comes from, which in turn can influence theories about the origin of extraterrestrial life.
“Our NWA 7533 samples were subjected to four different types of spectroscopic analysis – ways to detect chemical fingerprints,” said study author Professor Takashi Mikuchi of the University of Tokyo.
“We found strong evidence of magma oxidation.
“Magmatic clusters or fragmented rocks in a meteorite are formed by magma and are usually caused by impacts and oxidation.
“This oxidation may have occurred if there was water on or in the Martian crust 4.4 billion years ago during an impact that melted part of the crust.”
The analysis also suggests that such an effect would release a lot of hydrogen.
‘[This] it would contribute to the warming of the planets at a time when Mars already had a dense insulating atmosphere of carbon dioxide, “Mikuchi said.
NORTHWEST AFRICAN METEORITE
Weight: 84 g
Weight: 320 g
Nearly a decade ago, two meteorites were discovered in the Sahara Desert, Africa – NWA 7034, found in 2011, and NWA 7533, discovered in 2012, from which Mikuchi and colleagues took a sample for analysis.
NWA stands for North West Africa and the number is the order in which meteorites are officially approved by the Meteoritical Society, an international planetary scientific organization.
It is now known that both meteorites came from Mars, thanks to comparisons of evidence gathered by Mars landers.
To confirm the Martian origin of NWA 7533, comparisons were made by NASA’s Viking mission in the 1970s, which landed some of the earliest human instruments on the surface of the Red Planet.
“Some of these meteorites contain retained gas, which coincides with the atmosphere of Mars analyzed by the Mars exploration mission, NASA Viking.”
NWA 7533 and the more famous NWA 7034, better known as the “Black Beauty”, are part of the same group of at least 10 fragments, all with different numbers, according to Mikuchi.
“These Martian meteorites have different but identical oxygen isotope ratios from other alien materials, so we know they come from the same parent body,” he told MailOnline.
“They all fell to Earth from the same event, but probably fragmented as the atmosphere entered and scattered in the Sahara Desert.
“Later, people took it separately and the fragments were given different names.”
In 2013, NWA 7034 was 2.1 billion years old – the second oldest Martian meteorite after NWA 7533.
Scientists said that at that time, the meteorite the size of a cricket ball contained evidence of more water than any other Martian meteorite found on Earth.
Part of NWA 7034 was donated to the University of New Mexico by an American who bought it from a Moroccan meteorite dealer.
Many of today’s Martian meteorites have been discovered in the Sahara by Bedouin tribes who know that rocks can bring a lot of price to the Casablanca market.
The new study is published in Science Advances.
WHAT IS METEORITE NWA 7034 – WE ALSO KNOW AS BLACK BEAUTY?
Northwest Africa (NWA) 7034, nicknamed the Black Beauty, led to the creation of a new class of meteorite when it was discovered in 2011 in the Sahara Desert.
NWA 7034’s weighs approximately 11 ounces (320 grams).
After more than a year of intensive research, a team of American scientists found in 2013 that the meteorite formed 2.1 billion years ago.
This was the beginning of the most recent geological period on Mars, known as the Amazon.
Previous NASA studies have also found that the Black Beauty contains about ten times more water than other Martian meteorites.
NWA 7034 is made of cemented fragments of basalt, a rock that is formed by rapidly cooled lava.
The fragments are mainly feldspar and pyroxene, most likely from volcanic activity.
The chemistry of this unusual meteorite coincides with that of the Martian crust, measured by NASA’s Mars Exploration Rovers and the Mars Odyssey Orbiter.
Researchers theorize that the large amount of water contained in NWA 7034 may have originated from the interaction of rocks with the water present in the crust of Mars.
The meteorite also has a different mixture of oxygen isotopes than has been found in other Martian meteorites, which may be the result of interaction with the Martian atmosphere.