NASA was always supposed to look close to home as well as out to the stars. In 1958 the U.S. Congress chartered the agency to focus on “phenomena in the atmosphere and space.” Through Earth-observing satellites, nasa has vastly improved weather forecasting and natural disaster prediction and relief. It may have even helped to save the world when, in the 1980s, it showed that a dangerous hole in the planet's protective ozone layer was growing.* The data spurred the international community to ban ozone-destroying chlorofluorocarbon chemicals.

This year congressional Republicans seem to have decided they have had too much of a good thing and have moved to decrease nasa's Earth science budget. They have been egged on by Senator Ted Cruz of Texas, who has big ambitions—he announced his run for president this year—but little respect for science. Cruz, chair of the Senate Subcommittee on Space, Science, and Competitiveness, said in a hearing that Earth science was not part of the agency's “core mission” to space and, indeed, that it was not “hard science” at all. But this choice between our planet and others is a false one.

In June the House of Representatives, led by Republicans, passed a budget of $18.5 billion (which is what the White House had requested) but reshuffled where the money was to be spent. It slashed Earth science funding by $260 million and added extra money for planetary science that the agency did not ask for. For example, nasa requested $30 million for a robotic mission to Jupiter's icy moon, Europa, but the House gave it $140 million. The Senate Appropriations Committee, also pushed by the Republican majority, approved a version of nasa's budget that reduced total funding by $239 million. At press time, Congress needed to reconcile these competing bills.

Several Republicans, such as Cruz and Representative John Culberson of Texas, claim that funds used by the agency for gazing down at Earth would be better spent examining other worlds. The cuts, many say, actually pare back years of Earth science largesse from the Obama administration that underfunded other agency initiatives.

This argument is misleading. The current administration did increase nasa's Earth science budget but only to redress a nearly 40 percent cut such science suffered between 2001 and 2006, during the George W. Bush administration. Then, as now, actions were driven in large part by antiscientific opposition to evidence that global warming has a human trigger.

Another agency, the National Oceanic and Atmospheric Administration, also has eyes on Earth. But neither Republicans nor Democrats in Congress have supported noaa with much fervor. For instance, in 2012 Democratic Senator Barbara Mikulski of Maryland tried to move several noaa satellites to nasa. And in the Obama administration's 2016 budget, noaa requested $30 million for a study of ocean acidification, which is driven by climate change. The House granted $8.4 million, cut noaa's total budget by about 5 percent and gave nasa's Europa project that $110-million boost. “Don't tell me that there isn't money available,” fumed Democratic Representative Sam Farr of California during a House debate. “It is just the priority where you give it. Are you going to save this planet or put all the money into the moon of Jupiter?”

NASA researchers have successfully placed rovers on Mars and tracked the depletion of groundwater that is exacerbating the current drought in the American West. Of all federal agencies, this one is best positioned to study the heavens and the major environmental changes that affect our lives on Earth. Political extremists need to back off from their budgetary meddling and let the agency do both its jobs. The clock is ticking: the new fiscal year starts in October.

*Editor's Note (11/4/15): This sentence from the print article was edited after posting to clarify the original, which could have been read to state that NASA discovered the ozone hole.