A 5,000-pound dead satellite resembling a spaceship from Star Wars is hurtling towards Earth, but don’t worry—experts say situations like this happen “every week or two.”
Launched in 1995 by the European Space Agency from Kourou, French Guiana, the European Remote Sensing 2 (ERS-2) array spent over a decade-and-a-half observing the planet’s topography and weather events, including natural disasters in remote, hard-to-document regions. Alongside its sibling, ERS-1, the pair were considered the “most sophisticated Earth observation spacecraft” ever developed at the time of their deployment.
— ESA Operations (@esaoperations) February 19, 2024
In July 2011, however, the ESA decided to retire its “nominally” functioning ERS-2 and begin a scheduled deorbiting process. The satellite underwent 66 maneuvers over the ensuing month, using up its remaining fuel to descend from an altitude from roughly 487-miles to 356-miles above the Earth’s surface. Since then, ERS-2’s orbit has slowly decayed to its current point—caught in the planet’s gravitational pull, and picking up speed as it falls into the atmosphere.
On Sunday, the ESA posted grainy, black-and-white images to X taken last month by the Australian commercial imaging company, HEO, which show ERS-2 (then about 150-miles high) spiraling downwards during its final journey. From the camera’s vantage, the satellite certainly looks a lot like an incoming TIE Fighter from Star Wars.
But no need to evade Imperial scrutiny—or even fiery orbital debris, for that matter. ERS-2 is currently falling at a rate of over 6.2 miles per day, a speed expected to accelerate as atmospheric drag takes an even greater hold. As of February 20, ERS-2 has around 120-or-so miles left to go, and will start breaking up and bursting into flames once about 50 miles high. Most, if not all, of the subsequent detritus will then immolate to harmless dust and ash, posing an extremely low damage risk for anything or anyone below it.
[Related: Some space junk just got smacked by more space junk, complicating cleanup.]
The ESA estimates ERS-2 will burn away around 3:53PM EST on Wednesday, although trackers offer as much as a 7-hour window on either side to account for “unpredictable solar activity” that could influence its descent speed. As to where in the world the satellite will fall apart—well, that part is a little more difficult to predict at the moment, although more accurate geolocation estimates are expected over the next day.
Deorbiting satellites is vital to ensuring enough room is kept for the thousands upon thousands of other human-made objects orbiting Earth. Increasingly crowded skies is a major concern for space agencies, private companies, and watchdog groups—an issue that isn’t likely to diminish anytime soon. Back in October, for example, a space junk cleanup mission proved more complicated when another piece of debris smacked into the satellite targeted for decommissioning. In the meantime, regulators like the FCC are fining companies for failing to do their part in accounting for their dead satellites.
After all, while a single satellite burning up during deorbit isn’t cause for concern—a “Kessler cascade” most certainly is.
Source : Popular Science