The European satellite ERS-2, which completed its Earth observation mission 13 years ago, should burn up almost entirely in the atmosphere on Wednesday, apparently without risk for Earthlings, according to the latest forecasts from the European Space Agency (ESA).
The fallout operation on our planet, quite rare at ESA, began in 2011 to prevent an accidental destruction of this object in orbit from dispersing debris dangerous to active satellites and the International Space Station (ISS).
ESA's European Space Operations Center (ESOC) forecasts the final re-entry of the satellite into the lower layers of the atmosphere for Wednesday at 11:14 GMT, with an uncertainty margin of plus or minus 15 hours.
This margin, which was still more or less 48 hours a week ago, is explained by the fact that the machine falls naturally, by the force of gravity alone, and not in a directed manner.
It thus crosses upper layers of the atmosphere which more or less slow down its descent, and also make it difficult to predict where some of its debris could fall.
Most of the 2.3 tonnes of ERS-2 is expected to burn up when it reaches the lower layers of the atmosphere on Wednesday, at an altitude of around 80 km.
“It is estimated that the largest fragment of the satellite that can reach the ground is 52 kg
,” Henri Laur, from the Earth Observation Directorate at ESA, declared last week.
The chance of one of these debris hitting a person on the ground is less than one in a hundred billion, according to the ESA blog dedicated to the mission.
In other words, the risk for a human is 65,000 lower than that of being struck by lightning.
ERS-2, a pioneering Earth observation satellite
On average, an object with a mass similar to ERS-2 ends its days in the atmosphere once every one or two weeks, according to the ESA.
Monitoring of the satellite during its last days in space is carried out by ESOC, with European, German and American institutional partners.
A pioneer satellite in Earth observation, ERS-2 was launched in 1995 and placed at an altitude of nearly 800 km.
In 2011, at the end of its mission, the ESA brought it back down to around 500 km, so that it then descended naturally and gradually towards Earth in just 13 years.
Instead of the 100 to 200 years it would have taken if it had remained at its initial altitude.
Deprived of its internal energy (fuel, batteries, etc.), it presented significant risks of exploding and creating debris.
In July 2023, the European satellite Aeolus returned to Earth in a controlled manner, from an orbit (300 km) lower than that of ERS-2.
Debris from the machine fell into the Atlantic Ocean.
A “zero debris” charter
ESA launched a
“zero debris”
charter in 2023 for space missions designed from 2030.
“More than 100 organizations, including Airbus, Thales Alenia Space, Safran, have announced their intention to sign the charter
,” indicated last week Quentin Verspieren, coordinator of the space security program at ESA.
Waste from used satellites, rocket parts and collision debris has accumulated since the beginning of the space age.
A problem that has accelerated in recent decades.
According to ESA estimates, there are around a million pieces of satellite or rocket debris larger than a centimeter in orbit, large enough to
“disable a spacecraft”
in the event of an impact.