O céu cai sobre nossas cabeças, literalmente (The Washington Post)

 Tudo o que o chefe gaulês, Abraracourcix, da série de Goscinny e Uderzzo das afenturas de Asterix e Obelix, mais temia: que le ciel nous tombe sur la tête.
Pois ele está caindo, e seus efeitos podem ser perigosos, se não catastróficos, dependendo do objeto, satélites cuja vida útil já se esgotou.

Why space debris matters for Trump’s agenda
The Washington Post, July 15, 2026

The Neil Gehrels Swift Observatory, nearly 22 years into what was only meant to be a two-year mission, is falling out of orbit. Without intervention, it will come crashing back to Earth.

The situation could have been ripped from a sci-fi screenplay — and so could the solution NASA devised: launching a three-armed spacecraft to intercept the falling observatory, which carries NASA telescopes, and push it, over the course of about a month, into a higher orbit. It’s a relatively novel strategy — it’s only been done once before, by China four years ago — and one NASA may be forced to use more and more frequently in the coming years.

“Every satellite lower in orbit, a couple hundred miles up or so, 400 miles or so, eventually they’re all going to come down, it’s just a matter of how long,” said John Crassidis, a professor of aerospace engineering at the University at Buffalo and former NASA scientist.

What to do about the increasing number of satellites and many random debris floating around Earth is taking on increased importance under President Donald Trump, who has made ensuring “a future of American dominance in space” a cornerstone of his agenda.

As of 2024, NASA estimated there were more than 45,000 human-made objects orbiting Earth, around 14,500 of which are active satellites. Some of these satellites have boosters built in, so when their missions are completed they can be pushed into a high enough orbit that they’ll never fall back to Earth. But much of the random debris one finds floating in space — old satellites, rocket stages and other parts of spacecraft, things astronauts discard, intentionally and not — do not.

Atmospheric drag can cause objects in a low orbit to lose speed and fall out of orbit. Usually, they then burn up in Earth’s atmosphere, though occasionally pieces make their way to land, or, more frequently, sea. The Earth is 71 percent water, and humans inhabit a fraction of the terra firma, so falling space debris is most likely to land somewhere humans aren’t. But that’s not always the case, like in 2024, when debris from the ISS damaged a Florida family’s home, or 2025, when debris from a SpaceX launch landed in a Polish village.

The amount of space debris has increased sharply in recent years, much of it because of commercial satellites and space programs, raising the likelihood of space debris reaching Earth. The risk to humans is still very, very small. The risk to space missions and satellite activity is not.

Even small bits of debris can damage communications or GPS satellites, and active satellites are having to dodge space debris more and more. Elon Musk’s Starlink satellites had to maneuver around debris 144,000 times in the first half of 2025 alone. These maneuvers cause fuel to be used up more quickly, effectively shortening their lifespans, and cause gaps or errors in data collection in systems that do things like provide early warnings of natural disasters.

These collisions are even more dangerous for manned space travel.

The International Space Station already has to routinely re-route to avoid collisions with space debris. NASA has called off at least one spacewalk because of the dangers posed by debris to astronauts. Launch windows, spacecraft trajectories and the satellite data that make mission planning possible are all affected by the growing cloud of space debris. Manned missions are a key part of Trump’s space efforts — with his desire to see man return to the moon and go to Mars — but the space that astronauts will travel to is radically more crowded than when Apollo 11 made it to the moon in 1969.

“We’ve got to get the astronauts through that debris field if we want to go to the moon or Mars,” Crassidis said. “So we’re putting our astronauts in harm’s way too.”

Sen. John Hickenlooper (D-Colorado) has led the most significant legislative effort to address the Earth’s orbital dumpster, introducing the bipartisan Orbital Sustainability (ORBITS) Act in the last few sessions of Congress. It passed the Senate unanimously in 2022 and 2023, only to get shelved in the House. It passed out of committee again this year, and Hickenlooper recently introduced the act as an amendment to the National Defense Authorization Act (NDAA).

The bill, in its most recent form, would direct NASA to publish a list of the debris that poses the greatest risk to spacecraft in orbit and develop technology to repurpose or remove space debris from orbit.

“Earth orbits are turning into a junkyard. Space junk and debris pose a real risk to American satellites and jeopardize future space exploration,” Hickenlooper said in a statement to The Washington Post. “Every day we wait is another day that debris piles up.”

Scientists are doing their best to come up with ways to deal with the debris, exploring everything from nets to scoop it up to harpoons to impale it and move it away. At the moment, moving debris either via built-in boosters or another spacecraft is the most reliable method. But some plans show promise, like one to create a giant oven in space that can cook the debris and turn it into fuel.

Even the most promising of these plans are likely still decades out from practical use. But as Crassidis notes: “Today’s science fiction is tomorrow’s reality.”