WASHINGTON, July 7 — 260. That is the number of Starlink satellites SpaceX intentionally deorbited and burned up in Earth’s atmosphere over a six-month period from January to June 2024. The bottom line: Each of those satellites weighs roughly 2,700 pounds — about 1,225 kilograms.
Vaporizing that much hardware in the upper atmosphere is raising questions among environmental scientists about what exactly is being left behind. SpaceX, the aerospace company founded by Elon Musk, operates the Starlink constellation, which as of 2024 consisted of over 5,500 satellites in low Earth orbit.
The controlled reentry of aging satellites is part of the company’s end-of-life disposal plan, designed to reduce orbital debris. Company statements and tracking data confirm the 260 deorbits in that six-month window. But the environmental cost of that disposal method is drawing scrutiny.
When satellites reenter and burn up, they release aluminum oxides and other metals into the upper atmosphere. A 2023 study by researchers at the University of Southern California estimated that reentering satellites could increase atmospheric aluminum levels by up to 650% over natural background levels.
The Federal Communications Commission is currently weighing a proposal to exempt certain satellite constellations from environmental review under the National Environmental Policy Act. The FCC has argued that the cumulative environmental impact of these reentries is minimal. Environmental groups see it differently.
The Union of Concerned Scientists has urged the FCC to require full environmental impact statements before approving large satellite constellations.
By the numbers
The sheer scale of the Starlink fleet makes the disposal math worth watching. With over 5,500 satellites already in orbit and more launches planned, the number of deorbits will only grow as older satellites reach the end of their operational lives. Each satellite, at roughly 2,700 pounds, carries its own mass of metals and materials that end up vaporized in the atmosphere.
The 260 deorbits in the first half of 2024 represent a snapshot. The USC study’s 650% figure for potential aluminum increase provides a benchmark.
Natural background levels of aluminum in the upper atmosphere come primarily from micrometeorites and tiny dust particles from space. Satellite reentries could dwarf that natural input.
The regulatory picture
The FCC’s consideration of exempting satellite constellations from NEPA review is the key regulatory development to watch. NEPA requires federal agencies to assess the environmental effects of their actions before making decisions. An exemption would streamline approvals for companies like SpaceX but would bypass the kind of environmental impact statement that environmental groups are demanding.
The Union of Concerned Scientists has been vocal on this point. The group argues that the cumulative effect of thousands of satellite reentries warrants a full environmental review, not a blanket exemption.
The FCC has not yet made a final decision on the proposal.
What to watch next
The Starlink constellation continues to grow. As of 2024, it had already surpassed 5,500 satellites in low Earth orbit. Each new satellite launched will eventually need to be deorbited, adding to the atmospheric load.
The FCC’s decision on the NEPA exemption proposal will be a milestone. If the agency grants the exemption, satellite operators will face fewer environmental hurdles.
If it denies the exemption or requires environmental impact statements, the regulatory path for large constellations could become more complicated. Scientists are also likely to continue studying the atmospheric effects. The USC study from 2023 provides an early estimate, but more data will be needed to understand the long-term consequences of vaporizing thousands of tons of satellite hardware in the upper atmosphere.
For now, the numbers are clear: 260 satellites, each weighing 2,700 pounds, burned up in six months. The question is what that means for the atmosphere — and whether regulators will ask for the full environmental picture before the next wave of deorbits begins.
