By Pierre Brisson.
They will leave between July 14 and August 5 and will arrive some 7 to 9 months later in the vicinity of Mars.
Dangerous missions
This time the missions are from the United States, China and the United Arab Emirates (with a Japanese launcher). The member countries of ESA (European Space Agency) have unfortunately declared forfeit.
Not all of them have the same chances of success, that is to say of putting into orbit around Mars and especially of landing on its surface. Of the three missions, only the American and the Chinese have the objective of landing; and for the Chinese this landing, if successful, will be a first.
In reality, only the United States has demonstrated its ability to launch into orbit as well as to descend to the surface, that is to say to successfully carry out the difficult succession of maneuvers of the “EDL” (” Entry, Descent, Landing ”).
This is why the statistics on past experiences which claim to prove the low chances of successfully landing on Mars without referring to the country of the launcher or the date of the launch, do not make any sense. And they have all the less if we take into account the whole series of attempts.
All countries of the world combined, there have been 54 launches for Mars since 1960, including 11 flyby and “gravitational assistance” (simple overflights and overflights to go farther than Mars), 25 for orbits and 18 for landings.
The Americans have made 23 launches, they have failed five times but the last time was a long time ago, in 1999, with Mars Polar Lander; and of the five, they have failed to land once (the same Mars Polar Lander). There has been no further failure since that date (10 successful serial launches).
On the other hand, the Russians carried out 22 launches, they failed 19 times and succeeded only three operations including one flyby, only one orbit (for the ESA MarsExpress mission, using their Soyuz launcher) and no landing.
The Europeans have succeeded, alone (with their Ariane 5G + launcher), only one operation, the putting into orbit of the first part of the ExoMars mission (Trace Gas Orbiter) in 2016 while the landing part (Schiaparelli) failed. As mentioned above, the other operation, Mars Express, was carried out with a Russian launcher.
Japan tried and failed once, India tried and succeeded once (Mangalyaan orbit).
Finally, we cannot count in the same statistics the attempts of the 1960s and those of today. Technologies have evolved and the Americans have learned very quickly to do what they could not do for the good reason that they had not tried (the American launch will take place this time again (as for the MSL mission carrying Curiosity in November 2011) with an Atlas 5-541 rocket).
All 2020 missions have not the same scientific potential.
Different missions, different capacities
The United Arab Emirates, with the “Hope Mars Mission”, must send from July 14, a “technological demonstrator”. They want to show that they are capable of participating in a mission to go to the orbit of Mars and deploy scientific instruments there. It is “simply” to send, place and use an orbiter (satellite); no question of trying to descend to the ground for a first mission.
Officially Hope (or al-Amal, “Hope”) will study the atmosphere and the climate on the ground with two spectrometers, one operating in the infrared to measure the variability of the thermosphere and the losses of different gases, the other in the ultraviolet to study , in the medium and low atmosphere, temperatures, water vapor and variations in dust content.
The Japanese Launcher, Mitsubishi’s H-IIA, is a reliable launcher that has propelled many missions, including some into deep space. The operation, scientifically minor, therefore has a good chance of success.
China is in the same register of the demonstration of capacity. She wants to launch an orbiter and a lander “Mars Global Remote Sensing Orbiter and Small Rover”, mission now known as “Tianwen-1” which can be translated as “search for celestial truth” (“Huoxing-1” or “HX -1 ”during the development phase). It is also a first since so far this country has only launched to the Moon.
Beyond the engineering and political demonstration, the object will be the search for past or present traces of life and the“Assessment of the planet’s surface and environment”, rather vague expression which announces a work of study of the atmosphere, the magnetic field and geological cartography (a high resolution camera will be on board).
Of course the vector will be Chinese, a “Long March 5” rocket (or “Changzheng 5” or “CZ-5”); heavy launcher with a low track-record; two failures followed by two successes over four attempts, the placement of a satellite in a geostationary orbit and then another satellite in low Earth orbit. The mass to descend to the surface of Mars is equal to a quarter of the mass of Curiosity or of the new Perseverance rover.
Success or failure will be verified on several levels. Successful launch into deep space would be a confirmation of the reliability of CZ-5, which would already be good; succeeding in orbiting around Mars would be less difficult; Achieving a smooth payload on Mars would be an extraordinary performance. The scientific object is secondary.
The American mission: the most useful?
After the withdrawal of Europeans from ESA (for fear of not mastering EDL and of poor coordination with the Roscosmos Russians), the most serious and by far the most useful mission on the scientific level, is the American mission.
NASA’s rover Perseverance (“March 2020” during the development phase) is in my opinion relatively less attractive than its ex-competitor Rosalind Franklin from ESA. It is the continuation of Curiosity and aims to also search for traces of past life (Curiosity was trying to find out if Mars had been habitable, which is not the same thing), to prepare a future return of samples and prepare for the coming of man to Mars.
It includes seven instruments which, for several of them, are improvements of those which equip Curiosity today.
The Mastcam-Z is a panoramic and stereoscopic camera with a strong zoom capacity. It will be the eyes of the rover and it will have a role to play in the mineralogical identification.
MEDA (Mars Environmental Dynamics Analyzer) is a set of sensors that will give all the information on the weather (including the dust content of the atmosphere and the size of the particles).
MOXIE (Mars Oxygen ISRU Experiment) is an instrument which must test the possibility of producing oxygen from carbon dioxide in the Martian atmosphere (one of the recommendations made by Robert Zubrin in the 1990s).
PIXL (Planetary Instrument for X-Ray Lithochemistry) is an X-ray fluorescence spectrometer with a high resolution imager to determine the composition of surface rocks. The goal is to allow a finer chemical analysis than previously.
RIMFAX (Radar Imager for Mars’ Subsurface Experiment) is a radar which must make it possible to determine the geological structure of the ground on the scale of the centimeter (up to a depth of ten meters).
SHERLOC (Scanning Habitable Environments with Raman & Luminescence of Organics & Chemicals) is a spectrometer which must determine mineralogy on a small scale and detect organic compounds.
SuperCam is a kind of improved ChemCam (embedded on Curiosity). The instrument can remotely detect the presence of organic compounds in the regolith or the rocks.
In addition to these instruments, the American rover will have, like its predecessor, a robotic arm with a drill capable of taking samples which will either be analyzed on site, or preserved in a “cache” while awaiting a return mission from samples in the late 20’s or early 30’s (it’s far away and it’s really frustrating!).
The samples will remain very shallow (the planned drill is unfortunately not that of Rosalind Franklin which could have gone up to two meters deep, that is to say under the irradiated area with doses such that life is very improbable !).
Finally, the mission will land a small helicopter to test the possibility of using this type of vehicle in future explorations. It is interesting because it is true that close Martian exploration suffers from having to be carried out exclusively with a rover which rolls on a ground by definition not prepared for the circulation of wheeled vehicles.
We have seen that Spirit died from having entered quicksand and that the wheels of Curiosity were very quickly damaged which prevented him from making a lot of interesting observations. It is impossible to observe / analyze an interesting site even a few meters away if it is inaccessible to the rover and out of range of your ChemCam. That said, this first helicopter, named “Ingenuity”, will only have a very limited range and will only carry one camera. Hope he can fly!
Other ongoing missions
These missions will be added to those that are still in progress. First the ESA orbiters, ExoMars-TGO, “in great shape” (end of mission planned for 2022), and Mars Express which will continue its observations until the end of 2020; then the NASA orbiters, MRO, the Mars-Reconnaissance-Orbiter launched in August 2005, with its HiRISE camera which always gives us photos of extraordinary precision (resolution up to 0.3 meters per pixel) and which has extended, the old 2001-March-Odyssey which has enough energy to operate until 2025 and MAVEN which has completed its mission but still communicates, without forgetting, in orbit, the demonstrator Mangalyiaan from India, and on the ground the Curiosity rover on the ground as well as the InSight probe which continues to do seismography. MRO, Mars Odyssey, MAVEN and MarsExpress will serve as relays for new rovers for telecommunications to Earth.
The exploration of Mars therefore continues. After the withdrawal of the Europeans, the search for life is now carried by the Americans alone. We can hope for exciting new information and in any case a better knowledge of this planet, the most similar to Earth and the only one on which we can consider going physically with today’s technologies and where I hope we will end up going one day not too far away.
The slow progression that NASA undertook towards this objective (2040s?) Could be, fortunately, accelerated by Elon Musk who wants to lead a first inhabited expedition in 2024 (but if this date was postponed to 2026, it would not be too much serious). Hopefully he will be able to finalize his SuperHeavy launcher and his Starship ship and that the proponents of planetary protection will not put a stick on his wheels by preventing his takeoff or rather his landing on Mars!
China is looming in the shadows. Its capabilities are still far behind that of the Americans but the deposit on Mars soil of a working rover would greatly improve their credibility.
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