Space industry pollution above could have serious consequences for the environment below

Damage to the ozone layer could raise the risk of skin cancer, cataracts and immune disorders, says science reporter Shannon Hall.

As the space industry grows, more stuff is being left behind in our atmosphere by space vehicles. Last year, over 2,600 objects, including rockets and satellites, were launched into space, according to Our World in Data, a research publication.

When a spacecraft is launched, it leaves behind a stream of pollutants, many of which end up in Earth’s stratosphere. This exhaust as well as the debris left behind is contributing to what scientists call space pollution. And there’s a real concern that this superterrestrial pollution could have an impact on Earth’s environment.

Freelance science journalist Shannon Hall recently wrote about space pollution for The New York Times. “Marketplace” host Kai Ryssdal spoke with Hall about her piece, starting their conversation with a question about what’s being done to regulate the industry. Below is an edited transcript of the interview.

Shannon Hall: We are doing very little. So at the moment, nobody regulates the atmosphere. The Environmental Protection Agency, the Federal Communications Commission and the Federal Aviation Administration do not assess the environmental impacts of rocket launches on our atmosphere.

Kai Ryssdal: So, let me actually get that straight. SpaceX or Blue Origin or NASA or whoever launches rockets — SpaceX, specifically willy nilly, right, because it’s a booming business — there’s nobody who’s keeping an eye on the emissions from those rockets?

Hall: Not with respect to the atmosphere.

Ryssdal: And that that’s not great.

Hall: No, it is not great. And scientists are really concerned about how that could impact our environment.

Ryssdal: Say more about that, because it cannot possibly be good for the environment.

Hall: So scientists are concerned that rocket exhaust will collect in the atmosphere. Many scientists compare this pollution to that from a volcanic eruption. When Mount Pinatubo erupted in 1991, it belched enough sulfur dioxide gas into the atmosphere to heat the stratosphere. And scientists are concerned that the black carbon or soot released from current rockets will act much like those volcanic particles. Now, the stratosphere is home to the ozone layer, which protects us from the sun’s harmful radiation. So that means that as these launches skyrocket, they could actually raise the risk of skin cancer, cataracts and immune disorders, all because they have damaged the ozone layer.

Ryssdal: We do have some data on what the emissions are, right? I mean, you describe at the beginning of this piece a NASA pilot and scientist flying through the plume of a SpaceX rocket.

Hall: Yeah, so we do have several initial studies. One study, for example, found that the soot from rockets is nearly 500 times as efficient at heating the atmosphere as soot released from sources like airplanes. The study that you referenced actually has to do with the opposite side of the equation. So not only do these companies have to launch satellites into orbit via rockets, but those satellites also fall back to the Earth. Many satellites have a lifetime of five to 15 years. And at that point, they’re actually designed to fall back to the Earth and disintegrate in the atmosphere. But that leaves a stream of pollutants in their wake. And we have already seen those pollutants embedded within roughly 10% of the most common particles in the stratosphere.

Ryssdal: You point out that the scientists who are expressing legitimate concern about this do not want to strangle the space economy. And you point to things like Starlink, which is Elon Musk’s company that delivers internet to underserved areas and a bunch of other stuff, but that’s a whole other podcast. They’re aware of the business opportunity that space is, right?

Hall: Oh, absolutely. And there are huge benefits from the satellites. I mean, consider a natural disaster. Communication satellites could provide data to hospitals and local businesses, helping keep everything afloat so that disaster survivors could get the help they need. That’s huge.

Ryssdal: Are people actually working on the challenges that you lay out in this piece?

Hall: Yes. And I think it’s important to note that scientists don’t want to stop the booming space economy, but they want to take a beat. They want to do the research, which is what they’re working on now, to know how many rocket launches will be too many, so that we don’t find ourselves in a position where we have already caused harm to the environment and it’s too late.