Updated February 21, 2024 at 4:55 PM ET
A dead European Space Agency (ESA) satellite called European Remote Sensing 2 (ERS-2) came crashing to Earth on Wednesday.
Thankfully, it stayed true to the one-in-a-billion odds and didn't land on anyone's head, but rather, reentered the atmosphere over the Pacific Ocean at about 12:17 p.m. ET.
"No damage to property has been reported," the ESA said on its website.
The satellite was launched in 1995, retired in 2011, and has been gradually making its way back to Earth since then.
On Tuesday the ESA predicted that the defunct satellite would reenter the Earth's atmosphere at 11:32 a.m. ET on Wednesday, give or take 4 1/2 hours.
That uncertainty was due primarily to the influence of unpredictable solar activity, which affects the density of the Earth's atmosphere and therefore the drag experienced by the satellite.
The space agency expected the satellite to break into pieces at about 50 miles above the Earth's surface with the vast majority burning up in the atmosphere. Officials also predicted that some fragments would make it to Earth and fall into the ocean.
On Wednesday morning, expert astronomer Jonathan McDowell posted on Twitter that the satellite reentry was on a track from Alaska to the Pacific.
Soon afterward, the ESA confirmed that it was over the North Pacific Ocean between Alaska and Hawaii and next that it re-entered the Earth's atmosphere over the Pacific.
And, last but not least, the official report.
— ESA Operations (@esaoperations) February 21, 2024
Goodnight everyone. Goodnight ERS-2.https://t.co/IHGEMFQ7Ze#ERS2reentry
The backstory
"The odds of a piece of satellite falling on someone's head is estimated at one in a billion," ESA space debris system engineer Benjamin Bastida Virgili said during a press briefing last week, according to Phys.org.
Henri Laur from the ESA Earth observation mission said the largest fragment that could reach the ground would weigh about 115 pounds, the website reported. The mass of the whole satellite is roughly 5,000 pounds.
Over its 16-year life, the ERS-2 collected information on climate change and the Earth's atmosphere. Along with its older sister satellite ERS-1, it used: "an imaging synthetic aperture radar, a radar altimeter and other powerful sensors to measure ocean-surface temperature and winds at sea," the ESA said. The ERS-2 also carried another sensor to measure atmospheric ozone.
The space agency said the two satellites gathered information on "diminishing polar ice, changing land surfaces, sea-level rise, warming oceans and atmospheric chemistry."
The ESA decommissioned ERS-2 in 2011 and maneuvered it from an orbit of about 490 miles down to 360 miles above the Earth. It ran out of fuel and out of batteries.
The goal was to bring it down gradually and prevent it from adding to the big problem of orbital space junk. About 500,000 marble-sized objects are in orbit and there are more than 100 million objects 1mm or smaller, according to NASA. Another 25,000 objects are bigger than 10cm.
Most of the debris comes from satellite explosions and collisions. And when objects hit each other, they can create even smaller pieces of debris. The average impact speed is usually 22,000 mph, meaning even tiny objects can be dangerous.
The ESA says that on average, an object of similar mass to the ERS-2 reenters the Earth's atmosphere every one to two weeks.
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