Google’s plan to put data centers in the sky faces thousands of (little) problems: space junk

Satellite breakups and satellite antibody tests have created an alarming amount of debris, a crisis now exacerbated by the rapid expansion of commercial constellations like SpaceX’s Starlink. The Starlink network includes more than 7,500 satellites, which provide global high-speed Internet.

The US Space Force is tracking more than 40,000 objects larger than a softball using ground-based radar and optical telescopes. However, this number represents less than 1% of the lethal objects in orbit. The majority are too small for these telescopes to reliably identify and track them.

In November 2025, three Chinese astronauts aboard the Tiangong space station had to delay their return to Earth because their capsule collided with a piece of space debris. Back in 2018, a similar incident on the International Space Station challenged US-Russian relations, with Russian media speculating that a NASA astronaut may have deliberately sabotaged the station.

The orbital envelope targeted by Google’s project — a sun-synchronous orbit about 400 miles (650 kilometers) above Earth — is a prime location for uninterrupted solar energy. In this orbit, the spacecraft’s solar arrays will always be in direct sunlight, where they can generate electricity to power the onboard AI payload. But for this reason, sun-synchronous orbit is also the busiest highway in low-Earth orbit, and objects in this orbit are the most likely to collide with other satellites or debris.

As new objects arrive and existing ones disintegrate, LEO could approach Kessler Syndrome. In this theory, once the number of objects in low-Earth orbit exceeds a critical threshold, collisions between objects generate a cascade of new debris. Eventually, this series of collisions may render certain orbits completely unusable.

Implications of Project Suncatcher

Project Suncatcher proposes a constellation of satellites carrying large solar panels. They will fly in a radius of just one kilometre, with each node less than 200 meters apart from each other. To put that in perspective, imagine a racetrack roughly the size of Daytona International Raceway, with 81 cars racing at 17,500 mph — while separated by gaps about the distance you need to brake safely on the highway.

This ultra-dense configuration is necessary for satellites to transmit data to each other. The constellation divides complex AI workloads across all 81 of its modules, enabling it to “think” and process data simultaneously as one massive, distributed brain. Google is teaming up with a space company to launch two prototype satellites by early 2027 to validate the hardware.

But in the vacuum of space, flying in formation is a constant battle against physics. While the atmosphere in low Earth orbit is incredibly thin, it is not empty. The scattered air molecules create an orbital drag force on the satellites. This force pushes against the spacecraft, slowing it down and forcing it to descend in altitude. Satellites with larger areas have greater problems with drag, as they can act like a sail catching the wind.

To add to this complexity, streams of particles and magnetic fields from the Sun — known as space weather — can cause the density of air molecules in low Earth orbit to fluctuate in unpredictable ways. These fluctuations directly affect orbital drag.

When the distance between satellites is less than 200 metres, the margin of error evaporates. A single collision can not only destroy one satellite, but send it flying to its neighbors, setting off a cascade that can wipe out the entire group and randomly scatter millions of new pieces of debris into an orbit that has already become a minefield.

The importance of active avoidance

To prevent collisions and cascades, satellite companies can adopt Leave No Trace, which means designing satellites that don’t splinter, spew debris, or endanger their neighbors and can be safely removed from orbit. For a dense and complex constellation like Suncatcher, meeting this standard would require equipping satellites with “feedback” that detects and moves autonomously through the debris field. The current design of the Suncatcher does not include these active avoidance capabilities.

In the first six months of 2025 alone, SpaceX’s Starlink constellation performed an astonishing 144,404 collision avoidance maneuvers to dodge debris and other spacecraft. Likewise, Suncatcher will likely encounter debris larger than a grain of sand every five seconds.

Today’s object-tracking infrastructure is generally limited to debris larger than a softball, leaving millions of smaller pieces of debris virtually invisible to satellite operators. Future constellations will need an on-board detection system that can effectively detect these small threats and maneuver the satellite autonomously in real time.

Equipping the Suncatcher with active collision avoidance capabilities would be an engineering feat. Because of the tight spacing, the constellation will need to respond as a single entity. The satellites would need to realign their positions in unison, similar to a synchronized flock of birds. Each satellite will need to respond to the slightest shift from its neighbor.

Pay rent for the orbit

However, technological solutions can only go so far. In September 2022, the Federal Communications Commission established a rule requiring satellite operators to remove their spacecraft from orbit within five years of mission completion. This usually involves a controlled deorbit maneuver. Operators must now reserve enough fuel to power the thrusters at the end of the mission to lower the satellite’s altitude, until atmospheric drag takes over and the spacecraft burns up in the atmosphere.

However, the rule does not address debris already in space, nor any future debris resulting from accidents or accidents. To address these issues, some policymakers have proposed imposing a use tax to remove space debris.

A usage tax or orbital user fee would tax satellite operators based on the orbital pressure imposed by their constellation, much as larger or heavier vehicles pay higher fees to use public roads. These funds will fund active debris removal missions, which capture and remove the most dangerous pieces of waste.

Avoiding collisions is a temporary technical solution, not a long-term solution to the space debris problem. While some companies are eyeing space as a new home for data centers, and others continue to send constellations of satellites into orbit, new policies and active debris removal programs can help keep low-Earth orbit open for business.

Mojtaba Akhwan-Tafti, associate research scientist, University of Michigan

This article is republished from The Conversation under a Creative Commons license. Read the original article.