A satellite known as ERS-2, weighing as much as an adult male rhinoceros, is expected to reenter Earth’s atmosphere this week, according to the European Space Agency (ESA). The latest estimates suggest that the reentry could occur on Wednesday, although there is a window of about 15 hours earlier or later than the projected time. The ESA emphasizes that due to the nature of the return, it is impossible to predict the exact timing and location of the satellite’s entry into the atmosphere.
ERS-2’s return is classified as “natural” because its batteries have been depleted, and its communication antenna and onboard electronics have been switched off. This renders it impossible to control the satellite’s motion from the ground during its descent. The decision to deplete ERS-2’s fuel was made in 2011 to reduce the risk of a catastrophic explosion that could generate significant space debris.
Despite the satellite’s sizable mass, the ESA assures that most of it will burn up upon reentry, with any remaining fragments likely to fall into the ocean. Importantly, none of these fragments are expected to contain toxic or radioactive materials. The ESA also emphasizes that the risk of injury from space debris is extremely low, with the annual probability of such an event being less than 1 in 100 billion, which is significantly lower than the risk of being struck by lightning.
Launched on April 21, 1995, ERS-2 served as an Earth observation spacecraft, gathering data on various aspects of the planet’s surface, including land surfaces, oceans, and polar caps. The satellite also played a crucial role in monitoring natural disasters such as severe flooding and earthquakes. However, its mission came to an end in 2011 when the ESA initiated the deorbiting process to safely dispose of the satellite.
The deorbiting process involves using the remaining fuel to lower the satellite’s average altitude, ensuring that it would naturally reenter Earth’s atmosphere within a predetermined timeframe, in this case, within 15 years. By deorbiting ERS-2, the ESA aims to prevent collisions in orbit and minimize the creation of additional space debris, contributing to the long-term sustainability of space activities.
