NASA’s InSight lander has ‘heard’ and recorded the vibrations of four space rocks as they slammed into Mars over the past two years.
Not only are these the first impacts detected by the spacecraft’s seismometer since InSight landed on the Red Planet in 2018, it also marks the first time that seismic and acoustic waves from an impact have been detected on Mars.
The US space agency has released a recording of one of the Martian meteoroid impacts, with a distinctive ‘bloop’ sound heard three times as the space rock enters the atmosphere, explodes into pieces and hits the surface.
The impacts ranged from 85 to 290 kilometers away from the stationary lander in a region of Mars called Elysium Planitia, a smooth plain just north of the planet’s equator.
The first of the four meteoroids – the term for space rocks before they hit Earth – made the most dramatic entry.
NASA’s InSight lander has ‘heard’ and detected the vibrations of four space rocks as they slammed into Mars over the past two years (pictured)
Not only are these the first impacts recorded by the spacecraft’s seismometer since InSight landed on the Red Planet in 2018, it also marks the first time that seismic and acoustic waves from an impact have been detected on Mars
EXPLAINED: THE DIFFERENCE BETWEEN AN ASTEROID, METEORITE AND OTHER SPACECRAFT
An asteroid is a large chunk of rock left over from collisions or the early solar system. Most are located between Mars and Jupiter in the Main Belt.
ONE comet is a rock covered in ice, methane and other compounds. Their orbits take them much further out of the solar system.
ONE meteor is what astronomers call a flash of light in the atmosphere when debris burns up.
This waste itself is known as a meteoroid. Most are so small that they evaporate in the atmosphere.
If any of this meteoroid reaches Earth, it is called a meteorite.
Meteors, meteoroids and meteorites usually originate from asteroids and comets.
For example, if the Earth passes through the tail of a comet, much of the debris burns up in the atmosphere, forming a meteor shower.
It entered the Red Planet’s atmosphere on September 5, 2021 and exploded in at least three fragments, each leaving a crater.
NASA’s Mars Reconnaissance Orbiter then flew over the estimated impact site to confirm the location.
It used its black-and-white context camera to reveal three dark spots on the surface.
After locating these spots, the orbiter’s team used the High-Resolution Imaging Science Experiment camera, or HiRISE, to get a close-up color image of the craters.
“After InSight’s three-year wait to detect an impact, these craters looked beautiful,” said Ingrid Daubar of Brown University, a co-author of a new research paper on the discovery and a specialist in Martian impacts.
After reviewing previous data, the researchers confirmed that three other impacts had occurred on May 27, 2020, February 18, 2021, and August 31, 2021.
Scientists have wondered why they haven’t detected more meteoroid impacts on Mars.
The Red Planet is adjacent to the Solar System’s main asteroid belt, which provides an ample supply of space rocks to scar the planet’s surface.
Since Mars’ atmosphere is only 1 percent as thick as Earth’s, many meteoroids pass through it without disintegrating.
InSight’s seismometer has already recorded over 1,300 Martian earthquakes.
Provided by France’s space agency, the Center National d’Études Spatiales, the instrument is so sensitive that it can detect seismic waves thousands of kilometers away.
But the September 5, 2021 event marks the first time an impact was confirmed as the cause of such waves.
InSight’s team suspects that other impacts may have been obscured by wind noise or by seasonal changes in the atmosphere.
But now that the distinctive seismic signature of an impact on Mars has been discovered, scientists expect to find more hiding within InSight’s nearly four years of data.
The US space agency has released a recording of one of the Martian meteoroid impacts, with a distinctive ‘bloop’ sound heard three times as the space rock enters the atmosphere, explodes into pieces and hits the surface
The impacts ranged from 85 to 290 kilometers away from the stationary lander in a region of Mars called Elysium Planitia, a smooth plain just north of the planet’s equator
Seismic data provide various clues that will help scientists better understand the Red Planet.
Most Mars earthquakes are caused by underground rocks cracking from heat and pressure. Studying how the resulting seismic waves change as they travel through different material gives scientists a way to study Mars’ crust, mantle and core.
The four meteoroid impacts confirmed so far have produced small earthquakes with a magnitude of no more than 2.0.
These smaller earthquakes give scientists only a glimpse of the Martian crust, while seismic signals from larger earthquakes, like the magnitude 5 event that occurred in May 2022, can also reveal details about the planet’s mantle and core.
But the impacts will be crucial in refining Mars’ timeline.
Seismic data provide various clues that will help scientists better understand the Red Planet
“Impacts are the clocks of the solar system,” said the paper’s lead author, Raphael Garcia of the Institut Supérieur de l’Aéronautique et de l’Espace in Toulouse, France.
‘We need to know the impact speed today to estimate the age of different surfaces.’
Scientists can approximate the age of a planet’s surface by counting its impact craters—the more they see, the older the surface.
InSight’s data, in combination with orbital images, can be used to reconstruct a meteoroid’s trajectory and the size of its shock wave.
Each meteoroid creates a shock wave when it hits the atmosphere and an explosion when it hits the ground. These events send sound waves through the atmosphere.
The bigger the explosion, the more this sound wave tilts the ground when it reaches InSight.
The lander’s seismometer is sensitive enough to measure how much the Earth tilts from such an event and in what direction.
“We’re learning more about the impact process itself,” Garcia said. “We can match different sizes of craters to specific seismic and acoustic waves now.”
The new article has been published in the journal Nature Geosciences.
WHAT ARE SOME OF THE KEY FEATURES OF MARS?
The Mars Curiosity rover was initially launched from Cape Canaveral, a US Air Force base in Florida, on November 26, 2011.
In late January 2018, the Curiosity team on Earth received abundant new images from the rover through a record-setting relay from Nasa’s Maven orbiter, surpassing a gigabit of data during a single relay session from Mars for the first time in history.
NASA’s Jet Propulsion Laboratory in Pasadena, Calif., released this image as a single panorama image that provides an overview of the rover’s path along the crater’s outer rim.
The image shows a number of key features that the rover discovers on its travels. This included:
– Darwin is an impact crater that is about 109 miles (176 km) in diameter.
– It was first discovered by an orbiting spacecraft
– Experts believe it may reveal the internal makeup and history of the plains on the floor of Gale Crater.
– It could also provide insight into past water flows and can provide evidence of whether water played a role in the layering of rocks in the region.
– This area is Curiosity’s landing site
– It was named after the late author Ray Bradbury, who wrote various books about Mars, including ‘The Martian Chronicles’.
– The cliffs at Yellowknife Bay record an ancient lake and stream deposits
– This area could have offered favorable conditions for microbial life.
– Rocks were exposed about 70 million years ago by the removal of overlying layers due to wind erosion
– The name of this dune field is a tribute to British military engineer Ralph Bagnold (1896 to 1990), who studied how winds move sand particles from dunes on Earth.
– These dunes are actively migrating. They are the first active dunes explored in situ on another planet
– Scientists hope it will help us understand modern winds and aeolian processes
– Experts believe that intense underground steam explosions created these ‘twin’ craters.
– The larger of the two craters was named Arima after a city on the island of Trinidad, and the smaller crater has been left unnamed.
– Both are more than 31 miles (50 km) across.
– The smaller crater has several staggered terraces between the upper edge of the crater wall and the floor
– Many nearby smaller impact craters indicate that there was water or ice underground on the planet in the past