NASA and SpaceX are filling the Earth with space junk

The first launch of the European space rocket Ariane 6 was almost successful: on July 9, it launched the payload into orbit. But the second stage was unable to produce a braking impulse for a controlled descent from orbit and will now remain space debris. If the topic of space debris is already familiar, then the issues of its falling on our heads are underestimated by the manufacturers of rocket and space systems.

Alexander Baulin, leading manager of MTS Digital and a space fan, explains why the problem has only appeared now and what threat it poses to us.

What's happening?

Fragments of unburned spacecraft are increasingly being found in the United States. The apogee was a fragment of space debris from the ISS that broke through the roof of a house in Florida on March 8, 2024. Naturally, the agency did not plan to bombard earthlings, but expected the container with batteries to completely burn up in the atmosphere. Now the owner of the house has filed official request to NASA for compensation for damages.

The problem seems to be becoming widespread: spacecraft are more often sent into space, and then some of them return back – spent stages of launch vehicles, satellites, their fragments, etc.

In 2023, 223 starts took place – the largest number of launches launch vehicles in history, according to the Space Foundation. This year expected new record. United Launch Alliance and Arianespace will join SpaceX, which regularly launches, with new rockets, China and Russia are not slowing down, and a number of startups are planning launches. Let us recall that in 2025, the first launch of two rockets at once is expected: Firefly and Northrop Grumman, which I talked about earlier.

Often, dozens of devices are launched into space, primarily SpaceX's Starlink communications satellites. There are already more than 6,000 of them in orbit, and twice as many are planned. Similar projects are planned by Amazon – the Kuiper project – and Chinese companies, and, on a more modest scale, by other countries.

As a result, in a few years there will be several tens of thousands of devices in orbit. Their service life is about five years (possibly a little more), and after the end of their work, American companies are obliged to take them out of orbit. This seems like a better solution than leaving the devices in orbit as space debris. But let's do the math: it turns out that several satellites will enter the atmosphere every day. If the burnout is incomplete, tens and hundreds of fragments of space debris will fall to Earth.

Ideally, a satellite or spent stage of a launch vehicle is deorbited in such a way that it falls in a non-navigable part of the ocean, where there are no islands or ships. There, possible fragments will not cause harm to anyone. But this is expensive, since additional engineering equipment of spacecraft, additional fuel reserves for maneuvers, etc. are needed. In some cases, spacecraft and especially their fragments do not have fuel and engines, and therefore the ability to maneuver. They enter the Earth's atmosphere randomly.

Engineers from the Aerospace Corporation emphasize the need for additional study of the behavior of space debris during deorbit. This will allow a better understanding of the process of uncontrolled entry into the atmosphere of all types of space objects.

“Our main task now is to better understand the whole process and prepare for the use of new materials and approaches that are rapidly emerging.”” said Marlon Sorge, executive director of the Aerospace Corporation's Center for Research.

As a result, situations arise that are quite dangerous for humans. Above, I already mentioned a fragment of a battery container that was dropped from the ISS: in March 2024, its part broke through roof of a Florida home. In May of this year, a 90-pound chunk from the SpaceX Dragon fell to a glamping resort in North Carolina. And the owner of the house in the neighboring town found Another fragment from the same Dragon mission: in fact, only part of the SpaceX ship is reusable.

In May, another piece of the Dragon capsule, weighing more than 40 kilograms, was found on a farm in the Canadian province of Saskatchewan. NASA and SpaceX later determined that the debris fell in February. Space junk has also been found on the surface of the Earth in previous years: last year, Dragon debris fell in Colorado, and in 2022, a farmer in Australia found parts of the Dragon capsule on his land.

Equation with several unknowns

The problem of space debris is relatively new, not only because of the mass of launches, but also because of the use of new materials. Composite materials are increasingly used in rockets and satellites. Engineers are still studying how composites behave in extreme conditions during re-entry, where they are subjected to heating up to several thousand degrees and pressures that can destroy a spacecraft.

Greg Henning, a spokesman for the Aerospace Corporation, explains that it’s not just the materials of a composite that are important, but how they’re assembled together. Each manufacturer may use its own assembly methods, which results in unique material characteristics. Even if two composites are made from the same base materials (such as carbon fiber and epoxy), their final properties may differ depending on how they’re woven together.

“Does the craft tumble as it falls? Or does it enter the atmosphere in a stable configuration? There are a lot of factors that influence what happens during reentry,” says Greg Henning. “That makes it much more difficult to determine whether something like this will burn up completely.”

If the device tumbles or rotates, its surface experiences uneven resistance, which can lead to high loads and an increased probability of failure. In this case, it is difficult to predict the behavior of the device.

The aforementioned debris from several Dragon spacecraft is the remains of a “trunk,” an unpressurized cargo bay mounted behind the crew capsule. At the end of each mission, the Dragon capsule jettisons the unused trunk before beginning its deorbit maneuver and preparing to land in the ocean via parachute.

Crew Dragon diagram in frontal and lateral projections: A The crew capsule is a sealed compartment; B Crew capsule – service compartment; C “Trunk” is a non-hermetic cargo compartment. — 1 Heat shield – 2 SuperDraco Engine Nozzles (4 × 2) — 3 Solar panels – 4 Draco Engine Nozzles (4 × 3) — 5 Nose cone protecting the docking adapter – 6 Pilot chute hatch – 7 Crew evacuation hatch – 8 Hatch for 4 main parachutes – 9 Casing of pipes and cables connecting the crew capsule and the cargo compartment (for power supply and thermal control) – 10 Radiators – eleven Connector for connection to the launch complex – 12 Flaps for flight stabilization when the emergency rescue system is activated – 13 Portholes.

The baggage remains in orbit for several weeks or months, gradually descending. The entry into the atmosphere is uncontrolled, and the exact time of return can only be predicted with an error of several hours, even on the day of the event itself. This means that even an approximate location of the fall is extremely difficult to indicate.

SpaceX and NASA did not expect any of the Dragon's trunk to fall to Earth. “When the Dragon spacecraft's trunk was initially designed, an assessment was made of the destruction of the reentry trunk. The conclusion was that it would burn up completely,” it is said in a NASA statement.

Other countries have also seen large spacecraft fragments fall, especially China. But the biggest concern is still the communications satellites, because there are so many of them. Meanwhile, SpaceX is planning to launch a larger version of the Starlink satellites. Engineers will have a long way to go to study the problem, because no one on Earth wants a “garbage fall” of spacecraft fragments.