Amid a flood of news accompanying the 50th anniversary of the first moon landing, and continuing hype about humanity returning to the lunar surface and pushing on to Mars, a former deputy administrator of the U.S. National Aeronautics and Space Administration (NASA) says the agency should focus its attention closer to home.

“NASA was not created to do something again,” writes Lori Garver, the agency’s deputy between 2009 and 2013, in a Washington Post opinion piece. “It was created to push the limits of human understanding —to help the nation solve big, impossible problems that require advances in science and technology.”

And today, she adds, the impossible problem “is not the moon. And it’s not Mars. It’s our home planet, and NASA can once again be of service for the betterment of all.”

When the U.S. launched its quest for the moon more than half a century ago, devoting 4% of its total budget to NASA in 1965, its eye on the stars was driven by its decidedly earthly concern about the Soviet Union getting ahead in the space race, Garver recalls. Since then, successive White House administrations—Trump’s is the fifth—have proclaimed a target date to go farther. But each instance turned out to be “a decree without a value proposition that has never inspired broad public support nor come close to coming true.”

Now, while “NASA remains one the most revered and valuable brands in the world,” she adds, “the public doesn’t understand the purpose of spending massive amounts of money to send a few astronauts to the moon or Mars,” when robots could perform the scientific aspects of those missions for pennies on a dollar. She notes that 63% of the Americans who responded to a recent Pew Research Center study said monitoring key parts of Earth’s climate system should be NASA’s highest priority.

“The public is right about this,” Garver states. “Climate change—not Russia, much less China—is today’s existential threat. Data from NASA satellites show that future generations here on Earth will suffer from food and water shortages, increased disease, and conflict over diminished resources.” In response, extending the agency’s existing missions and developing new sensors and satellites “would increase the cadence of new, more precise measurements and contribute to critical, higher-fidelity climate models.”

The agency “could also move beyond measurement and into action—focusing on solutions for communities at the front lines of drought, flooding, and heat extremes,” she continues. “It could develop and disseminate standardized applications that provide actionable information to populations that are the most vulnerable. NASA could create a Climate Corps—modeled after the Peace Corps—in which scientists and engineers spend two years in local communities understanding the unique challenges they face, training local populations, and connecting them with the data and science needed to support smart, local decision-making.”

The massive data processing effort behind that work “would require an Apollo-scale change—but could be accomplished within [NASA’s] existing mandate and by shifting funding priorities.” And Garver notes the 1958 National Aeronautics and Space Act already mandates a “comprehensive program of research, technology, and monitoring to understand and maintain the integrity of the Earth’s atmosphere,” working in cooperation with international scientists, engineers, and organizations.

Against that combination of need and opportunity, “Apollo’s legacy should not be more meaningless new goals and arbitrary deadlines,” she concludes. “Let’s not repeat the past. Let’s try to save our future. Besides, humanity’s intrinsic need to explore is driven by our need to survive.”