{"id":12519,"date":"2020-04-20T19:02:52","date_gmt":"2020-04-20T11:02:52","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/nasa-narrows-design-for-rocket-to-launch-samples-off-of-mars\/"},"modified":"2020-04-20T19:02:52","modified_gmt":"2020-04-20T11:02:52","slug":"nasa-narrows-design-for-rocket-to-launch-samples-off-of-mars","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/nasa-narrows-design-for-rocket-to-launch-samples-off-of-mars\/","title":{"rendered":"NASA narrows design for rocket to launch samples off of Mars"},"content":{"rendered":"
\"\"
This illustration shows a concept of how the NASA Mars Ascent Vehicle, carrying tubes containing rock and soil samples, could be launched from the surface of Mars in one step of the Mars sample return mission. Credit: NASA\/JPL-Catlech<\/figcaption><\/figure>\n

After years of studies, test-firings and a survey of U.S. industry in preparation for launch of a Mars Sample Return mission in 2026, NASA has settled on a solid-fueled design for a miniature rocket with a first-of-its-kind purpose: Launching a payload from Mars for a trip back to Earth.<\/p>\n

The small launcher is called a Mars Ascent Vehicle, or MAV. The MAV will play a key role in the Mars Sample Return mission being developed by NASA and the European Space Agency.<\/p>\n

The first element of the Mars Sample Return mission is NASA\u2019s Perseverance rover scheduled to depart Earth in mid-July. Perseverance will collect core samples from Martian rocks and store them in tubes for retrieval by a future rover that could launch as soon as 2026.<\/p>\n

With two launches from Earth scheduled for 2026, NASA and ESA will send to Mars a stationary landing platform with the MAV, a mobile robot to fetch soil samples collected by NASA\u2019s Perseverance rover, and an Earth Return Orbiter to bring the specimens back home.<\/p>\n

The U.S.-built Sample Retrieval Lander will target a landing zone near Perseverance and deploy a European fetch rover to pick up the already-sealed sample tubes and deposit them back at the lander. The tubes will then be robotically transferred into the payload module on top of the Mars Ascent Vehicle, which will launch the samples into orbit around Mars.<\/p>\n

ESA\u2019s Earth Return Orbiter, fitted with NASA-supplied hardware to capture and contain the Mars samples, will rendezvous with the specimens in orbit around Mars and contain the alien soil in a return capsule to prevent contamination. Then the spacecraft will depart Mars and head for Earth, deploying the sample-carrying re-entry container to plunge into the atmosphere and crash-land the Utah desert in 2031.<\/p>\n

\u201cWe\u2019re actively working on humanity\u2019s first round trip to another planet,\u201d said Jim Watzin, director of NASA\u2019s Mars Exploration Program.<\/p>\n

With estimated cost of $7 billion, the multi-part mission is ambitious, but NASA officials argue it is achievable.<\/p>\n

\u201cWhen you look at the building blocks for the architecture, they\u2019re all, for the most part, either very similar to the things we\u2019ve done before, or at most an extension,\u201d Watzin said in an interview last week with Spaceflight Now. \u201cThe protection of the samples, the containment of the samples, that\u2019s new territory.\u201d<\/p>\n

Scientists want to protect the samples not only from contamination caused by terrestrial spores and organic materials from Earth. They\u2019re also focused on ensuring material from Mars does not endanger the Earth ecosystem, a concept known as backward planetary protection.<\/p>\n

\u201cWe\u2019ve invested for five years now in developing the concepts \u2026 and feel pretty comfortable that we have an angle on it,\u201d he said.<\/p>\n

\u201cWe\u2019re trying to keep this as simple as possible,\u201d Watzin said. \u201cThis is by no means a simple task. It is complex -\u2026 but you can keep it as simple as possible.\u201d<\/p>\n

One of the untried mission elements required for the Mars Sample Return program is the rocket that will boost the rock specimens off of the Red Planet.<\/p>\n

Based on preliminary design constraints, the Mars Ascent Vehicle can be no taller than 9.2 feet (2.8 meters) and no wider than 1.9 feet (57 centimeters). Its total liftoff mass must not exceed 881 pounds (400 kilograms).<\/p>\n

Martian gravity is just 38 percent that of Earth, meaning a rocket designed to launch a payload into orbit can be much smaller on Mars. And the MAV only has to deliver some 30 to 35 pounds (14 to 16 kilograms) of payload into orbit around Mars.<\/p>\n

The requirements stack up to create MAV concept that is tiny by launch vehicle standards, but it\u2019s just enough to do the job, according to NASA engineers.<\/p>\n

\"\"
This diagram illustrates one concept for a two-stage, solid-fueled Mars Ascent Vehicle. Credit: NASA\/MSFC<\/figcaption><\/figure>\n

Engineers at NASA\u2019s Marshall Space Flight Center in Huntsville, Alabama, have determined a two-stage, solid-fueled rocket is the best choice for the Mars Ascent Vehicle.<\/p>\n

NASA previously looked at using a single-stage hybrid propulsion system for the MAV, which would have burned a solid wax-based fuel in combination a liquid oxidizer. That made sense, Watzin said, because engineers were concerned the effects of a \u201ccold soak\u201d \u2014 or prolonged exposure to cold temperatures \u2014 on solid propellant grains.<\/p>\n

NASA worked with two hybrid propulsion providers to perform test-firings of hybrid rockets, but agency officials decided in the last few months to go with a two-stage Mars Ascent Vehicle powered by solid rocket motors.<\/p>\n

Officials selected Jezero Crater, home to an ancient dried-up river delta, as the landing site for the Perseverance rover, the centerpiece of NASA\u2019s Mars 2020 mission. That makes Jezero Crater the landing site and launch site for Sample Retrieval Lander and the MAV.<\/p>\n

\u201cWhen the landing site was picked for Mars 2020 as Jezero Crater, then the thermal regime that we had to be able to tolerate warmed up significantly, several tens of degrees centigrade warmer,\u201d Watzin said in a recent interview with Spaceflight Now. \u201cSo that brought us back into the trade space of also being able to look at solid rocket motors.\u201d<\/p>\n

Results from ground testing also showed a single-stage hybrid propulsion system was not quite ready to use in the Mars Ascent Vehicle.<\/p>\n

\u201cThe test program, the technology program, on the hybrids identified the fact that they still had some work to do in terms of being able to re-light the motors which we needed for the second burn to achieve orbit, and the strategies for providing the right oxidation, the right ignition characteristics that we needed,\u201d Watzin said. \u201cSo it was becoming more and more complex and apparent to be less and less mature than what we thought it was.<\/p>\n

\u201cMeanwhile, solid rocket motors are very much a known and established entity,\u201d Watzin said. \u201cThe technologies are well understood. So the advantages disappeared. We made a selection to go with something that we know and understand, that was not necessarily going to have a big challenge with the new, revised temperature limits that we\u2019re going to face.\u201d<\/p>\n

The MAV will launch in mid-2026 with the U.S.-built Sample Retrieval Lander and the European fetch rover. Under current mission plans, the rocket won\u2019t be fired until mid-2029 to begin the return trip to Earth.<\/p>\n

Watzin said NASA doesn\u2019t see the long-term storage of the solid-fueled MAV as one of the sample return program\u2019s biggest challenges.<\/p>\n

\u201cWe think there\u2019s a lot of analogy to what we do here on Earth,\u201d he told Spaceflight Now. \u201cThere\u2019s maybe a more direct analogy to missiles in some respects. A lot of missiles are built and stored for years, if not decades, before they\u2019re called into service to operate. So we know how to safely store motors. That\u2019s been done many, many times in both defense and aerospace science research and flight applications.<\/p>\n

\u201cAll our vehicles these days fly autonomously,\u201d Watzin said. \u201cWe\u2019ve been flying around Mars enough that we have a pretty good understanding of the gravity there. So we don\u2019t see that as a big challenge here.\u201d<\/p>\n