NASA landing The constancy of the rover next month will cause serious waves, some of which could help scientists better understand the structure of the Red Planet.
On February 18, it is planned to reach permanence, the central part of NASA’s $ 2.7 billion search mission, the Mars 2020 mission, which is located in Jezero Crater with a width of 28 miles (45 km). The epic landing will generate seismic signals that one of the rover’s cousins, NASA We lower the InSight Mars device, will try to detect from a distance of over 3200 kilometers, according to a new study.
If that happens, it will be a space flight first: No spacecraft has ever heard of such a landing on another planet in this way, said members of the InSight team.
The hypersensitive InSight seismometer has risen hundreds of hoses from the landing of the ship in November 2018 on a Martian plain known as Elysium Planitia. InSight members use these measurements to outline the interior of the Red Planet with unprecedented detail, the mission’s key goal.
However, such interpretive work can be complex.
“Unlike Earth, where you can find out for yourself when and where a [seismic] source happened, and of course how big it was, on Mars, we have a station and we are both trying to identify the mechanics of the source and the structure of the planet through which the waves propagate “, lead author of the study and member of the InSight team Ben Fernando, PhD student at Oxford University in England, told Space.com.
“The unraveling of these two from each other is not necessarily trivial,” he added. “In the simplest explanation, if you’ve been in a room and can’t see, it’s hard to tell if someone is talking very far away or quietly near you. And in addition, if you didn’t know what the shape of the room was , it would be even harder. “
Therefore, the landing of perseverance is a great opportunity for scientists from InSight – a chance to collect seismic data generated by the impact, the details of which are known in advance, Fernando and his colleagues write in the new study.
Mars 2020 will use the same entry, exit and landing strategy (EDL) as its predecessor, Mars rover Curiosity Mars, down safely in August 2012
Mars 2020 will strike Martian atmosphere difficult, to be significantly delayed by friction and then deploy a supersonic parachute to slow down further. About seven minutes after entering the atmosphere, a rocket sky crane will lower the Permanence to the floor of the Lake carefully with cables, then fly away to deliberately land a safe distance.
This last step will not generate seismic waves of significant force. But two other points during the EDL sequence are likely to produce relatively strong signals, according to Fernando and his team.
Such a signal will be triggered by a sound boom that will occur after Mars 2020 reaches within about 60 miles (100 km) of the Martian surface, an altitude at which the atmosphere is dense enough “for significant compression to occur.” , the researchers wrote in the new study.
Part of the energy from this boom – which will disappear when the spacecraft becomes subsonic, about three minutes before touching – will hit the surface of Mars and turn into seismic waves. But this signal will not be strong enough to be captured by InSight, which is about 3,445 miles (3,452 km) from Perseverance’s landing site, Fernando and his team estimate, citing the scattering effect of Martian winds as a key factor. .
The other signal will come through an actual surface impact – double blows, in fact. Shortly after Mars 2020 hits the atmosphere, the spacecraft will launch two “cruise mass balancing devices” (CMBDs) to change the center of its mass. CMBD, each weighing 170 lbs. (77 kilograms) will be dropped from a very high altitude, at an altitude of about 900 miles (1450 km), and will hit the ground at an approximate speed of 8,700 miles per hour (14,000 km / h), Fernando said.
Mars InSight in photos: NASA’s mission to explore the core of Mars
It is not clear how strong the seismic waves will be from the effects of CMBD; InSight has not yet found any confirmed effects on Mars, so forecasts are difficult. But Fernando and his team generated estimates based on data collected here on Earth and beyond. The moonand these figures suggest that InSight has a decent chance of measuring the waves.
“In the best realistic case (and assuming that the meteorological and noise spectra are the same for the same period a Martian year earlier), the required signal-to-noise ratio would be sufficient for positive detection in 40% of cases,” the researchers wrote. in a new study sent (but not yet accepted) by the journal Earth and Space Sciences. You can read free prepress from it here.
There is some luck associated with this relatively pink figure: CMBD-generated waves will arrive at the InSight location in the early evening on Elysium Planitia, the quietest part of the day, Fernando said.
Disclosure would be a big deal for InSight team members. They would know exactly how far and how fast the seismic waves traveled.
“If you know how fast they went, you can start to understand what the structures were through,” Fernando said.
Permanence will aim to document its own landing in an unprecedented way, among other things. Mars 2020 carries two microphones, one of which will experiment catch the dramatic sounds of EDL on February 18th. (The other is part of Perseverance’s SuperCam rock system.) So far, no spacecraft on Mars has successfully recorded the harsh sounds of the Red Planet.
Permanence is not the only spacecraft planned to land on Mars this year. Chinese The Tianwen-1 mission will arrive in orbit on February 10 and launch a landing and rover on the Red Planet about two months later, if all goes according to plan.
The InSight team would love to hear the landing of Tianwen-1, Fernando said. But details of the mission – in particular its exact landing time and location – are difficult to find, so “it is not possible to predict the detection of this signal” at the moment, the researchers wrote in the article.
The European-Russian program ExoMars launches a Lander Rover duet to Mars in 2022. InSight will almost certainly not be able to detect seismic signals from this landing sequence, given that the ExoMars duo will touch the other side of the planet from InSight, Fernando said.
SpaceX is looking forward to launching its next-generation Starship spacecraft to Mars soon. maybe in 2024said the company’s founder and CEO Elon Musk. If InSight lives long enough, it may be able to document the touch of one or more of these 165-meter-high (50-meter) stainless steel spacecraft.
“It’s not out of the question,” Fernando said. “It just depends on where they decide to land.”
Mike Wall is the author of “Out there“(Grand Central Publishing, 2018; illustrated by Carl Tate), a book on the search for extraterrestrial life. Follow it on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.