Dead, 5,000-pound satellite is falling to Earth today. Will any debris survive the fiery reentry?

Update for Feb. 21: This post was updated on Feb. 21 to indicate the latest reentry time predictions from ESA.

A European Space Agency spacecraft is making an uncontrolled nosedive into Earth’s atmosphere – with elements of the 2.3-ton spent satellite likely to survive the plunge into purgatory.

The exact time and place above Earth that the radar-scanning ESA European Remote Sensing (ERS-2) augers in is unknown, but a new prediction of the spacecraft’s demise has been issued.

Using the most recent data, ESA’s Space Debris Office predicted as of 6:30 a.m. EST (1130 GMT) on Wednesday (Feb. 21) that the reentry of ESA’s ERS-2 satellite will take place at 12:05 p.m. EST (1541 GMT) on Wednesday (Feb. 21).

a large H-shaped satellite in orbit

Artist’s illustration of ESA’s ERS-2 satellite in Earth orbit. The spacecraft is expected to fall back to Earth on Feb. 21.
(Image credit: ESA)

The uncertainty in this prediction is now just (+/- 1.44 hours), according to an ESA statement.

“This uncertainty is due primarily to the influence of unpredictable solar activity, which affects the density of Earth’s atmosphere and therefore the drag experienced by the satellite,” ESA adds.

a graph resembling a cone on its side, with the large end facing the left side

The latest graph showing how the predicted time of reentry has changed over the last month and a half. As we approach the reentry, the uncertainty in the prediction decreases. (Image credit: ESA/ESOC)

Leftovers

As for the ERS-2 re-entry itself, there’s likely to be post-re-entry spacecraft leftovers.

“It is likely that some parts survive the re-entry, as on average between 10 and 20 percent of the mass for large objects does,” says Simona-Elena Nichiteanu, a media relations officer in the communication department at the European Space Operations Centre (ESOC). ESOC serves as the main mission control center for ESA in Darmstadt, Germany.

a graph showing a line that sinks rapidly as it approaches the right side

The latest graph showing how the altitude of the ERS-2 satellite has changed over the last month, and how it is expected to change in the future. (Image credit: ESA/ESOC)

Component survival

As for the ERS-2 component survival to Earth’s surface, Nichiteanu told Space.com that the biggest and heaviest fragments that might survive reentry into the atmosphere are the 4 tanks (heaviest), the 3 internal panels supporting instruments (largest cross section) and the Synthetic Aperture Radar (SAR) antenna structure (largest fragment assuming it does not fragment at all).

a painting of a satellite with two square blue solar arrays at the bottom, and four skinnier, longer ligher blue arrays at the top. its body is rectangular. it floats before the black of space and above a slice of deserted Earth.

ERS-2 artwork. (Image credit: European Space Agency)

A vast majority of ERS-2 will “burn up” in the atmosphere, ESA experts explain. Furthermore, given that the Earth is largely ocean water-rich, chances are for splash down of any remaining spacecraft components.

Orbital debris regulation

The fall of ERS-2 can be viewed both as a calling card from space and a wake-up call.

“While the ESA should be lauded for its efforts to de-orbit the ERS-2, it should be unsurprising that a 2.3-ton satellite launched into Earth orbit without any enforceable orbital debris regulation will then return to Earth’s atmosphere as orbital debris in an explosive uncontrolled reentry,” said Michael Runnels, an assistant professor of business law at California State University, Los Angeles.

“Indeed, these events highlight the continuing need for enforceable orbital debris regulation to support the sustainable exploration and scientific investigation of outer space,” Runnels said.

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