By Dreams of exploring the cosmos have crashed up against the harsh reality of budget cuts in the United States. Congressional approval of the 2024 federal budget earlier this year left NASA with roughly half a billion dollars less than the agency had in 2023 — and Mars science has taken the biggest hit.
Engineers are scrambling to figure out how a long-planned mission to bring samples back from the Red Planet might still be accomplished. Probes intended for other planets and moons are delayed, and the venerable Chandra X-ray Observatory, which launched in 1999 and has transformed our view of energetic phenomena in the universe, is potentially on the chopping block.
Until now, NASA had been on its longest streak of regular budget increases in history, says Casey Dreier, chief of space policy at The Planetary Society in Pasadena, Calif. Between 2014 and 2023, funding had increased more than 3 percent on average compared with the previous year.
“That makes it easy to take on new projects,” Dreier says. “There’s room to grow. Everybody can win. And that has ended.”
NASA’s 2024 budget comes to $24.875 billion, a 2 percent cut relative to last year and 8.5 percent less than the requested funding. That’s the biggest discrepancy between requested and appropriated funding for the agency since 1992.
The budget’s approval immediately left it up to NASA administrators to figure out how to adapt and cover the $509 million gap.
“We know we are definitely in an imperfect environment, and we acknowledge this is a very challenging time,” Nicola Fox, NASA’s associate administrator for science, said in March during a public town hall. But, she vowed, NASA “will use every single penny to do great science.”
The Mars Sample Return mission faces the biggest cuts
NASA’s Mars Sample Return mission had intended to bring rock and soil samples to Earth from the Red Planet by 2033. But even before these budget cuts, questions emerged about whether the ambitious program, prioritized in 2022 as part of planetary scientists’ decadal survey, could meet its goals on deadline and at a reasonable cost (SN: 4/20/22). The budget cuts now mean the mission is on hold as NASA tries to determine if it can be done at all.
The Perseverance rover, currently roaming Mars’ Jezero crater, is the first step of sample return. Since arriving on Mars in 2021, the rover has been filling small tubes with material from specific locations, with the goal of eventually gathering 38 samples in total (SN: 2/17/21). The rocks and soil could answer fundamental questions about the formation of the inner solar system and the history of water on Mars, and perhaps reveal signs of past life on the planet.
Yet bringing these samples back from such a great distance is among the most complex mission proposals ever put forward, requiring a vehicle that could launch from the Martian surface and a way to transfer the samples to a second rocket in space to prevent possible contamination of our home planet. The decadal survey estimated the mission cost at between $5 billion and $7 billion total. NASA had hoped to spend around $950 million on it this year.
But two independent review boards pegged the overall expense for sample return much higher, potentially topping $11 billion — unacceptable to NASA administrators. In response to the approved budget, 2024 funding for the program was reduced by $630 million, essentially covering the full amount of the cost cutting that NASA needed to do and allowing for some other programs to have modest budget increases.
“Mars Sample Return took it on the chin for the entire agency,” Dreier says. The amount taken from this program, part of the planetary science division, “basically saved every other science division.”
NASA proposes spending just $300 million on the sample return mission this year and $200 million next year, which is just enough to string the program along as its future is figured out. And though it’s still unclear how much money NASA will receive next year, the 2025 budget requested by the Biden administration has been pared back.
The Jet Propulsion Laboratory in Pasadena, largely responsible for designing and building the components of sample return, “lost hundreds of millions of dollars functionally overnight,” Dreier says. Uncertainty over the budget had already prompted the center to announce it would dismiss 530 employees, or 8 percent of its staff, in February. “I’m positive you will see further layoffs at JPL and probably other NASA centers that were involved in Mars Sample Return,” Dreier says.
Meanwhile, NASA has put out a solicitation asking other NASA centers and engineers in the industry to propose innovative ways to bring back at least some of the samples at a lower cost. It may mean choosing which of the originally planned cache of samples — 24 of which have been collected so far — are most valuable.
Missions to other planets are delayed
Yet that doesn’t mean other missions are in the clear. A dedicated orbiter to explore the ice giant Uranus — the 2022 decadal survey’s second priority after the Mars sample return — has seen its timeline pushed back. Because ice giants are among the most common types of exoplanets being discovered around other stars, researchers are keen to understand those in our own solar system. But the researchers tasked with planning the effort “won’t even start thinking about that mission until 2028 at the earliest,” Dreier says.
DaVinci and Veritas, two missions to explore Venus, are also being delayed, and there’s now more uncertainty about which, if any, other probes on the drawing board — those intending to bring back samples from a comet or fly through the plumes of Saturn’s moon Enceladus — will go forward.
All this will mean less near-term research on the formation and dynamics of planets and their moons. “We forget how little we’ve explored the solar system we live in,” Dreier says. Scientists are crying out to explore it, he adds, and that’s all being pushed back.
Other missions, such as Europa Clipper, which is set to launch to the frozen moon of Jupiter in November, didn’t face cuts. Future probes including Dragonfly, heading to explore Saturn’s moon Titan, and the space-based Near-Earth Object Surveyor, which will scan for potentially hazardous asteroids, are still receiving the money they need.
While not strictly a scientific mission, NASA’s Artemis program, which aims to land humans on the moon again in the coming decade, saw a small funding increase for 2024. “Artemis was one of the few programs that more or less held its own,” says Marcia Smith, a space policy analyst and editor of the site SpacePolicyOnline.com.
The first Artemis test, an uncrewed swing around the moon, successfully completed its journey in 2022 (SN: 12/12/22). Future missions would assess how astronauts adapt to space exploration and return new rock samples from the moon — including from the lunar south pole, where some of the satellite’s oldest rocks are found.
While Smith expects that future Artemis missions might see delays, she thinks there’s enough momentum to ensure they’ll take off at some point. There’s a broad coalition in Congress who believe it to be important for staying ahead of China, which also aims to land people on the moon in the coming years.
Other NASA divisions’ budgets are flat
NASA’s planetary science division is suffering more from the cuts than the Earth science, biological and physical sciences, and heliophysics divisions, which are facing flat funding for the most part. A smaller than requested bump for NASA’s astrophysics division is adding scrutiny to some of its projects.
The budget for this year and expectations for next year have prompted NASA to conduct a review of its existing flagship telescopes, the Chandra X-ray Observatory and the Hubble Space Telescope, to see if either can be wound down. Both were launched as part of the first generation of Great Observatories in the 1990s and early 2000s, and they’ve already seen their companions, the Compton Gamma Ray Observatory and Spitzer Space Telescope, shut off.
Few expect that the famous Hubble will be shelved. Chandra’s future is less certain. Launched 25 years ago, the X-ray observatory has been delivering unparalleled imagery of the high-energy universe for decades, providing data on gorging black holes in the centers of galaxies, neutron star collisions, and gas and dust in the intergalactic medium. Its operational costs are on the order of $70 million per year. Yet NASA needs to free up funds for future observatories such as the Nancy Grace Roman Space Telescope, an infrared telescope scheduled to launch in 2027, and the Laser Interferometer Space Antenna, or LISA, a space-based gravitational wave detector that the agency is developing in partnership with the European Space Agency. The Roman telescope will hunt for exoplanets and study the nature of dark energy, while LISA will scan for merging black holes in galactic centers.
Though many scientists say Chandra is healthy enough to continue producing wonderful research, its aging infrastructure has officials eyeing its end. NASA administrator Bill Nelson stated in a congressional hearing that “Chandra has given us so many gifts,” but “it’s time for new missions.”
Answers on the telescope’s fate are expected in the near future, though it’s unclear exactly when.
