Methane, a powerful greenhouse gas, is thought to be responsible for more than a quarter of global warming experienced to date. Controlling it is such an urgent priority that President Joe Biden recently hosted a “Methane Summit” at the White House.

Most of the problem stems from just a few kinds of places: natural gas wells and pipelines, cattle feedlots, coal mines, rice paddies, and landfills. But occasionally, the scientists who hunt for large methane releases find them in surprising spots. Such was the case on June 4, when a plume of the gas was detected at the sprawling ranch in West Texas where billionaire Jeff Bezos tests space rockets.

It turns out that Bezos’s space company, Blue Origin LLC, routinely emits the stuff because it’s developing a rocket that runs on liquefied natural gas, which is almost pure methane. The June release was detected by an instrument on board the International Space Station, which happened to be zooming past that day. The nonprofit group Carbon Mapper analyzed the readings and estimated the gas was escaping at about 1.5 metric tons per hour. There’s no indication of how long it lasted.

“We frequently transfer LNG from our suppliers into storage tanks at our engine test stands. Everything operated normally,” said Sara Blask, a spokeswoman for Blue Origin, in an email. “There were no issues or reporting thresholds exceeded.” She declined to comment on how much gas was released. The state air regulator, the Texas Commission on Environmental Quality, doesn’t impose limits on methane emissions or require disclosure of releases.

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An air permit application filed with the TCEQ in January 2020 said the company expected to routinely dump LNG into the air to the tune of 3.4 million cubic feet a year, which would work out to more than 60 tons of methane. It’s unclear from state documents if those numbers reflect current operations, and Blask declined to clarify. She also didn’t comment on why the test site’s flare was not used to burn the gas, a step that would greatly reduce the climate impact.

Of course, Blue Origin’s emissions pale in comparison with those from its suppliers in the natural gas industry. Wells and pipelines in the Permian Basin, a huge oilfield near the rocket site, are thought to give off some 2.7 million tons of methane a year. And Blue Origin is not unique in developing methane-powered rocket engines; so are rivals including SpaceX.

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Methane is just a small part of the space industry’s overall impact on the climate — and that impact is not well understood. Exhaust particles emitted high above the earth can have an “umbrella” effect, preventing sunlight from reaching the ground, said Martin Ross, an atmospheric scientist at the nonprofit Aerospace Corp. Because of uncertainty around that and other aspects of space flight, scientists aren’t sure whether the industry causes net heating or cooling in the lower atmosphere, he said.

The question may get more attention in the coming years. Estimated to be worth $447 billion, the space industry could reach $1 trillion by 2030, according to estimates from McKinsey and the World Economic Forum. “The amount of emissions right now isn’t that great to be a significant contributor to the total of human impact on climate,” Ross said, but “we think there is going to be a lot of growth.”

Ironically, one of the growth drivers for the commercial space sector is launching satellites for environmental monitoring of pollutants, including methane.

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Bezos has argued that humans must colonize space because the Earth’s resources are finite. In a 2019 speech at Blue Origin, he envisioned a future in which dirty industrial activity took place off-world and that our home was “zoned for residential and light industry.” As he tweeted in 2018, “We go to space to save the Earth.”

The days of permanent space colonies are still a ways off. In the meantime, many of Blue Origin’s flights have ferried wealthy tourists on brief jaunts into space, including, in 2021, Bezos himself.

--With assistance from Loren Grush and Aaron Clark.