5,000-pound satellite expected to fall somewhere on Earth this week

The European Space Agency announced that its decommissioned Earth-observing ERS-2 satellite is anticipated to return to the atmosphere and disintegrate on Wednesday morning.

At least, it is expected to disintegrate. Some parts of the 5,000-pound spacecraft could hit the ground. 

Not to worry, though. The experts say the likelihood of being hit by space debris is less than 1 in 100 billion annually, a figure substantially lower than everyday risks such as household accidents.

In collaboration with an international surveillance network, the ESA’s Space Debris Office has been diligently tracking the satellite’s descent. Forecasts suggest that ERS-2 will reenter at approximately 3:53 p.m. ET on Wednesday. However, there is a 7.5-hour window of uncertainty due to variable factors such as solar activity.

Experts have emphasized that predicting the final reentry location and time is challenging due to the satellite’s “natural” uncontrolled descent. Fluctuations in solar activity, which influence the density of the Earth’s atmosphere and its gravitational pull on the satellite, add layers of complexity to the prediction models. With the sun approaching the peak of its 11-year cycle, these effects have become more pronounced.

At 5,057 pounds post-fuel depletion, the ERS-2 satellite is not lightweight, but it’s comparable in size to other space debris entering Earth’s atmosphere with some regularity. 

Once the satellite descends to about 50 miles above the surface, it is expected to break apart, with most pieces incinerating. Authorities assure that any surviving fragments pose no chemical dangers and will likely end up in the oceans.

During its operational years, the innovative ERS-2 worked in tandem with its predecessor, ERS-1, recording crucial observations on global environmental changes.

The mission focused on monitoring polar ice, marine environments, and terrestrial landscapes. It also played a pivotal role in disaster management, assessing the impact of floods and earthquakes in isolated regions. The legacy of ERS-2 lives on through the continued application of its data.