Large rock impact on Mars reveals craters and surface features

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Mars has many craters. Now it has two new ones — cut by rocks that crashed into the planet late last year.

Mars will be good. It is not a natural disaster. There is no sign that the earth is new Affected by asteroids. The solar system is full of junk. Mars has a weak atmosphere, and when a meteorite flies through space, it is unlikely to burn up before it hits the surface.

But what has scientists buzzing — NASA has scheduled a news conference Thursday to highlight the discovery, described in two. Papers Published Crater-forming impacts have been documented by two NASA spacecraft, an orbiter and a lander – in the journal Science. It was a nifty demonstration of combining scientific resources, one providing an eye on impact phenomena and the other providing an ear.

The result is an extraordinary array of data about the Martian interior that is of great interest to planetary scientists who want to understand why this rocky world, hot and humid 4 billion years ago, turned into a cold desert with no apparent sign of life.

It was also an event for the record books: According to Philippe Loughnonet, lead author of one of the newly published papers, a massive crater-forming impact on one of the Solar System’s rocky inner planets has been documented in real time.

The largest of the new craters is about 150 yards across and 21 yards deep, and formed so violently that it threw rocks 40 kilometers (nearly 25 miles) from the impact, according to Lilia Poziolova, a senior scientist at the Mall’s Space Science Systems. , which operates two cameras at NASA Mars Reconnaissance Orbiter.

Orbiter often sees the results of smaller impacts, leaving a feature a few yards in diameter. But in February, scientists in Posiolova’s team saw the largest crater detected by the orbiter. In fact, it was so large that it almost went unnoticed.

“It’s a big, big feature. You’re trained to see the little features. With your eye, you’re looking for blemishes,” Posiolova said.

The crater was discovered on February 11, but scientists knew they had other daily images of the Martian surface, and they went back in time to find when the crater appeared.

Posiolova recalled that NASA had another spacecraft on Mars Inside LanderStationed on the surface for four years to monitor seismic activity, it detected a major shock on Christmas Eve. Suddenly everything lined up. The first appearance of the crater in images taken from orbit coincided with a seismic signal recorded by a surface instrument.

Seismic data can then be analyzed in the context of distance to impact. This helped refine current models of the Martian interior, Lognonné said.

The larger of the two craters may have been caused by an object five to 12 yards in diameter, Posiolova said. He said that such an object in Earth’s atmosphere would burn up if it hit our planet.

The origin of the meteorites is unknown, but they likely came from the asteroid belt between Mars and Jupiter, he said.

“These impacts are huge, but we can continue to sleep well on Earth,” Lognonné said. “Our atmosphere protects us.”

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