NASA’s Mars Sample Return mission has a shaky future

This article originally appeared on The conversation.

A crucial NASA mission in the search for life beyond Earth, Mars sample return, is in trouble. Are the budget has ballooned from $5 billion to more than $11 billion, and the sample return date could move from the end of this decade to 2040.

The mission would be the first to attempt to return rock samples from Mars to Earth so scientists can analyze them for signs of past life.

NASA Administrator Bill Nelson said during a press conference on April 15, 2024 that the mission as currently conceived is too expensive and too slow. NASA gave private companies a month to submit proposals to bring back the samples in a faster and cheaper way.

Like a astronomer who studies cosmology and wrote a book about it early missions to Mars, I’ve seen the sample return saga play out. Mars is the closest and best place to look for life beyond Earth, and if this ambitious NASA mission were to unravel, scientists would lose their chance to learn much more about the red planet.

The habitability of Mars

The first NASA missions When he reached the surface of Mars in 1976, he found the planet to be an icy desert, uninhabitable without a thick atmosphere to protect life from the sun’s ultraviolet radiation. But studies conducted over the past decade suggest this could be the case much warmer and wetter several billion years ago.

The Curiosity And Perseverance rovers have each shown that the planet’s early environment was suitable for microbial life.

They found the chemical building blocks of life and signs of surface water in the distant past. Curiosity, which landed on Mars in 2012, is still active; his twin brother, Perseverance, which landed on Mars in 2021will play a crucial role in the sample return mission.

Why astronomers want Mars samples

The first time NASA looked for life in a rock on Mars was in 1996. Scientists claimed they had discovered microscopic fossils of bacteria in the Martian meteorite ALH84001. This meteorite is a piece of Mars that landed in Antarctica 13,000 years ago and was found in 1984. Scientists disagreed about whether the meteorite had actually once housed biology, and Today, most scientists agree that there is not enough evidence to say that the rock contains fossils.

A few hundred Martian meteorites have been found on Earth over the past 40 years. They are free samples that fell to Earth, so while it may seem intuitive to study them, scientists can’t say where these Martian meteorites came from. Moreover, they were thrown from the planet’s surface by impacts, and those violent events could easily have destroyed or altered subtle evidence of life in the rocks.

There is no substitute for it return samples from a region known to have been hospitable to life in the past. As a result, the agency is faced with a price tag of $700 million per ounce, making these samples the best most expensive material ever collected.

A compelling and complex mission

Returning Martian rocks to Earth is the most challenging mission NASA has ever undertaken, and the first phase has already begun.

The perseverance has been mustered more than twenty rock and soil samples, by depositing them at the bottom of the Jezero crater, an area that was likely once flooded and could have harbored life. The rover places the samples in containers the size of test tubes. Once the rover has filled all the sample tubes, it will collect them and take them to where NASA is Lander for collecting samples Will land. The Sample Retrieval Lander contains a rocket to get the samples into orbit around Mars.

The European Space Agency has one Earth Return orbiter, which will rendezvous with the rocket in orbit and capture the basketball-sized sample container. The samples are then automatically placed in a biocontainment system and transferred to an Earth Entry Capsule, which is part of the Earth Return Orbiter. After the long journey home, the access capsule will parachute to the Earth’s surface.

The complex choreography of this mission, involving a rover, a lander, a rocket, an orbiter and the coordination of two space agencies, is unprecedented. It’s the culprit behind the rising budget and long timeline.

Returning samples is worth a lot of money

Mars Sample Return has blown a hole in NASA’s budget, jeopardizing other missions that need funding.

The NASA center behind the mission, the Jet propulsion laboratory, just laid off more than 500 employees. It’s likely that Mars Sample Return’s budget was partly to blame for the layoffs, but it also came down to the Jet Propulsion Laboratory being overcrowded with planetary missions and suffering. cuts.

The past year has been one independent review board report and a report from the NASA Office of Inspector General increased deep concerns about the feasibility of the sample return mission. These reports described the mission design as overly complex and noted issues such as inflation, supply chain problems, and unrealistic cost and schedule estimates.

NASA is too feeling the heat of Congress. For the 2024 budget year, the Senate committee has cut NASA’s planetary science budget by more than half a billion dollars. If NASA cannot keep costs under control, the mission could even be canceled.

Think outside the box

Faced with these challenges, NASA has put out a call for innovative designs from private industry, with the aim of reducing mission costs and complexity. Proposals must be submitted by May 17, which is an extremely tight schedule for such a challenging design effort. And it will be difficult for private companies to improve on the plan that experts from the Jet Propulsion Laboratory had to draw up for more than a decade.

An important potential player in this situation is the commercial spaceflight company SpaceX. NASA already is partnership with SpaceX about America’s return to the moon. For the Artemis III missionFor the first time in more than fifty years, SpaceX will attempt to land humans on the moon.

However, the massive Starship rocket that SpaceX will use for Artemis has only had three test flights and needs much more development before NASA will entrust it with a human payload.

Basically one Spaceship rocket could return a large load of Martian rocks in a single two-year mission and at a much lower cost. But Starship comes up with great risks and uncertainties. It’s not clear if that rocket can return the samples Perseverance has already collected.

Starship uses a launch pad, and would need to be refueled for the return journey. But there is no launch pad or gas station at Jezero Crater. Starship is designed to carry people, but if astronauts go to Mars to collect the samples, SpaceX needs a Starship rocket that even bigger than the one who tested it so far.

Sending astronauts also comes with additional risks and costs, and a strategy that involves using humans could be more complicated than NASA’s current plan.

With all these pressures and constraints, NASA has chosen to see if the private sector can come up with a winning solution. We’ll know the answer next month.

Disclosure: Chris Impey receives funding from the National Science Foundation and the Howard Hughes Medical Institute.