The Aeolus satellite has been orbiting the planet at an altitude of 200 miles for five years, but now its fuel is nearly exhausted and gravity, bits of Earth’s atmosphere and solar activity are pulling it back down.
A defunct spacecraft the size of a small car is expected to fall to Earth within weeks, according to the European Space Agency.
ESA says its 1.3-ton Aeolus satellite is running out of fuel and falling about 0.6 miles (1 km) a day.
Although much of it will burn up in the atmosphere, some debris is expected to reach the planet’s surface — most likely in late July or early August.
In a first-of-its-kind maneuver, the space agency, of which the UK is a part, will use the remaining fuel in an attempt to safely guide the spacecraft to a remote part of the planet.
Tim Florer, head of ESA’s Space Debris Office, said: “This assisted re-entry attempt exceeds the safety rules for the mission, which was planned and designed in the late 1990s.
“Once ESA and industry partners determined that it might be possible to further reduce the already minimal risk to life or infrastructure, the wheels were set in motion.”
The Aeolus satellite in 2018. Photo: European Space AgencyAeolus orbits the planet at an altitude of 200 miles (320 km) for five years, measuring the wind in the atmosphere to improve weather forecasting.
But its fuel is almost spent – gravity and jets of the Earth’s atmosphere, as well as solar activity, are pulling the spacecraft down.
Once the satellite reaches an altitude of 174 miles (280 km), mission control in Germany will put it through a series of maneuvers over several days to bring it down to a 93-mile (150 km) orbit.
One final change in trajectory will put it on course to dive into the ocean, away from land.
ESA said in a blog post that it was impossible to give an exact time for the spacecraft’s re-entry.