NASA Spacecraft Record New and Larger Meteor Strikes on Mars
2022-11-02
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1Two NASA spacecraft have recorded the biggest meteor strikes and impact craters on Mars than ever before.
2One of the spacecraft is on Mars' surface.
3The other is orbiting the planet.
4The impacts last year produced seismic waves that travelled thousands of kilometers across Mars.
5These are the first seismic waves scientists have ever found near the surface of another planet.
6The hits produced craters nearly 150 meters wide, scientists reported Thursday in the journal Science.
7The larger of the two strikes threw out large pieces of ice.
8That information may help researchers find ways future astronauts can use Mars' natural resources.
9The Insight lander measured the seismic waves, while the Mars Reconnaissance Orbiter provided pictures of the craters.
10Liliya Posiolova of Malin Space Science Systems in San Diego is one of the study investigators.
11She said scientists were lucky to be able match the seismic waves with pictures of the impact craters.
12Mars' atmosphere is thin.
13On Earth, the thick atmosphere stops most space rocks from reaching the ground.
14Instead, the rocks break apart and burn in the atmosphere.
15InSight is close to the end of its operation.
16Its power equipment is covered in dust from storms on Mars and failing.
17InSight landed on Mars in 2018 and has since recorded more than 1,300 marsquakes.
18A marsquake is similar to an earthquake.
19Bruce Banerdt of NASA's Jet Propulsion Laboratory, the lander's chief scientist who took part in the studies, estimated the lander had between four to eight more weeks before power runs out.
20The space rocks were between 5 meters and 12 meters wide, said Posiolova.
21The larger of the two struck last December about 3,500 kilometers from InSight, creating a crater about 21 meters deep.
22The Orbiter's cameras showed material thrown as far as 40 kilometers from the impact.
23They also showed white spots of ice around the crater, the most frozen water observed at such low latitudes, Posiolova said.
24Posiolova found the crater earlier this year after taking extra pictures of the region from orbit.
25The crater was missing from earlier photos.
26After looking at older photos, the scientist dated the impact to late December.
27She also remembered a large seismic event recorded by InSight around that time.
28With help from the Insight team, Posiolova connected the new hole to the strike.
29Scientists also learned that the lander and orbiter both recorded an earlier meteoroid strike.
30It was more than double the distance of the December one and a little smaller.
31"Everybody was just shocked and amazed," Posiolova remembered.
32The seismic readings from the two impacts point to a denser Martian layer of ground beyond InSight's location.
33Doyeon Kim of ETH Zurich's Institute of Geophysics in Switzerland, was part of the research.
34He said scientists still have much to learn about the deeper structure of Mars.
35Outside scientists said future landers from Europe and China will carry even more advanced equipment to detect seismic waves.
36I'm Andrew Smith.
1Two NASA spacecraft have recorded the biggest meteor strikes and impact craters on Mars than ever before. 2One of the spacecraft is on Mars' surface. The other is orbiting the planet. 3The impacts last year produced seismic waves that travelled thousands of kilometers across Mars. These are the first seismic waves scientists have ever found near the surface of another planet. The hits produced craters nearly 150 meters wide, scientists reported Thursday in the journal Science. 4The larger of the two strikes threw out large pieces of ice. That information may help researchers find ways future astronauts can use Mars' natural resources. 5The Insight lander measured the seismic waves, while the Mars Reconnaissance Orbiter provided pictures of the craters. 6Liliya Posiolova of Malin Space Science Systems in San Diego is one of the study investigators. She said scientists were lucky to be able match the seismic waves with pictures of the impact craters. 7Mars' atmosphere is thin. On Earth, the thick atmosphere stops most space rocks from reaching the ground. Instead, the rocks break apart and burn in the atmosphere. 8InSight is close to the end of its operation. Its power equipment is covered in dust from storms on Mars and failing. InSight landed on Mars in 2018 and has since recorded more than 1,300 marsquakes. A marsquake is similar to an earthquake. 9Bruce Banerdt of NASA's Jet Propulsion Laboratory, the lander's chief scientist who took part in the studies, estimated the lander had between four to eight more weeks before power runs out. 10The space rocks were between 5 meters and 12 meters wide, said Posiolova. The larger of the two struck last December about 3,500 kilometers from InSight, creating a crater about 21 meters deep. The Orbiter's cameras showed material thrown as far as 40 kilometers from the impact. They also showed white spots of ice around the crater, the most frozen water observed at such low latitudes, Posiolova said. 11Posiolova found the crater earlier this year after taking extra pictures of the region from orbit. The crater was missing from earlier photos. After looking at older photos, the scientist dated the impact to late December. She also remembered a large seismic event recorded by InSight around that time. With help from the Insight team, Posiolova connected the new hole to the strike. 12Scientists also learned that the lander and orbiter both recorded an earlier meteoroid strike. It was more than double the distance of the December one and a little smaller. 13"Everybody was just shocked and amazed," Posiolova remembered. 14The seismic readings from the two impacts point to a denser Martian layer of ground beyond InSight's location. 15Doyeon Kim of ETH Zurich's Institute of Geophysics in Switzerland, was part of the research. He said scientists still have much to learn about the deeper structure of Mars. 16Outside scientists said future landers from Europe and China will carry even more advanced equipment to detect seismic waves. 17I'm Andrew Smith. 18Marcia Dunn wrote this story for the Associated Press. Andrew Smith adapted it for VOA Learning English. 19______________________________________________________________________ 20Words in This Story 21meteor -n. A piece of rock that flies into a planet from space 22impact -n. the sudden, often strong effect of something or the physical area where an object has struck another object 23crater -n. a hole in the ground created by the impact of an object such as a meteor or a bomb 24seismic -adj. referring to vibrations or shaking of a planet's surface in events such as earthquakes, volcanic eruptions, or explosions 25latitude -n. the distance of a location from a planet's equator 26amaze -v. to fill with sudden surprise, to astonish 27_______________________________________________________________________ 28We want to hear from you. 29We have a new comment system. Here is how it works: 30Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.