NASA and the European Space Agency (ESA) have been cooking up a way to get some of Mars back to Earth, so that samples can be analyzed in detail — just like the rocks the astronauts brought back during the Apollo missions, which gave us a deeper understanding of our Moon.
The Perseverance rover already on Mars has been seeking promising areas to investigate that might provide evidence of ancient past life, with the help of the Ingenuity helicopter drone. Recently, the two worked together to drive the rover to an old river delta, expected to be a prime location where such samples could be found.
The rover has been drilling and saving rock and dirt samples in onboard storage tubes. The difficulty is that getting them back to Earth requires another major undertaking.
Returning the Samples
Termed the “Sample Return Mission,” the two space agencies have been discussing for months how best to bring the samples back, and have now refined an approach. Given that Perseverance has been so good at the job it was given, the NASA/ESA team has decided that the rover should be used for the return mission in 2030 when things would be in operation on Mars. (We’re not sure if the warranty sticker on Perseverance will still be valid in 2030, but if past performance is an indication, all the rovers have significantly outlived their initial design lives.)
Its partner Ingenuity has graduated from proving it can fly in the thin Martian air to actually scouting routes for the large rover. Because Ingenuity has proven reliable and capable of traveling significant distances, NASA and ESA have decided that two new helicopter drones will become part of the return mission. They will be based on the successful Ingenuity design, but will be fitted with wheels, one on each of the four landing legs, to enable movement on the ground.
They will also be fitted with a device which is capable of picking up and carrying a sample tube. Since the prototype drone helicopter was designed to be as light as possible, this infers a substantial increase in lift capacity will be required. The original mission included a sample-collection rover, but this task will now be assigned to Perseverance, with the two sample-carrying helicopters acting as backup, if needed.
An earlier concept had the rover dropping sample canisters behind it as it progressed around the surface for subsequent pick up. This concept appears to have been shelved for the moment. Keeping the canisters onboard the rover throughout perhaps simplifies transfer to the return lander.
The Mars Ascent Vehicle would then carry the samples into orbit, to a waiting Earth Return Obiter, where the samples would be transferred to a return system for onward transit and atmospheric re-entry to Earth. Some of these details are a little sketchy, but there sure are a lot of moving (autonomous, robotic?) parts. This, of course, means a lot of opportunities for something to go wrong. No doubt continuing refinement of the mission will reduce the risks. The Jet Propulsion Lab (JPL) and AeroVironment designed and built Ingenuity — they may face some challenges developing the successor helicopter drones.
Meanwhile, Here on Earth…
Drones led the news Aug. 1, when President Biden announced the killing of Ayman al-Zawahiri in Kabul, Afghanistan. Al-Zawahiri topped the U.S. 9/11 wanted list, and his removal was all about the offensive use of drones. Presumably fired from a General Atomics Reaper variant drone at quite some altitude, two Hellfire AGM-114R9X “knife bomb”missiles took out al-Zawahiri as he stood alone on the balcony of a home in Kabul.
This means that video/infrared from high altitude was sufficiently clear to determine that the man was alone on the balcony, presumably confirming information on the ground that his family was elsewhere. So long-distance, high-level authorization was then granted to fire on him in a foreign country now run by the Taliban.
To minimize inadvertent casualties, the Hellfire R9X missile was used, which lacks explosive armaments. The weapon is a nasty piece of work, weighing ~100 lb with an inert payload, and fitted with six long knives that deploy before impact. This missile has previously been used in perhaps 11 other instances to take out terrorist individuals and minimize collateral damage.
This is another instance of how the U.S. use of military drones has become less devastating, but is still very deadly to the specific target.
To Sum Up
We’ve taken a quick glimpse at how NASA and ESA are planning more drones for the surface of Mars, and a much more aggressive use of drones here on Earth.
