You read that right: a satellite hit Earth on Wednesday, February 21. The dead European satellite entered the atmosphere at 12:15 EST over the Pacific Ocean between Alaska and Hawaii.
The 5,057-pound now-defunct satellite was named the European Remote Sensing (ERS-2) satellite. ERS-2 was in space for 16 years and made a “natural” reentry back into the atmosphere. The satellite was originally launched on April 21, 1995, by the European Space Agency (ESA). With ERS-1, ERS-2 provided vital information on the Earth’s land surfaces, ocean temperatures, ozone layer, and polar ice extent. This helped to observe natural disasters such as flooding and earthquakes in remote areas. Many of the advancements in satellites were due to the information collected by ERS-2.
ESA used the last of the fuel in ERS-2 and then emptied its batteries. By lowering the satellites from 785 kilometers to 573 kilometers, the risk of collision with other satellites and space debris was low. Thus, ERS-2 was uncontrollable during reentry and completely dependent on atmospheric drag, making it a “natural” reentry. The ESA was closely monitoring the satellite to ensure that the landing would not be harmful to civilian populations. As soon as ERS-2 was 50 miles from the Earth’s surface, the satellite disintegrated into fragments. According to the ESA, it is possible that fragments from the satellite reached the surface, but the pieces were not toxic and likely fell into the ocean.
The ESA decided to deorbit the satellite in 2011. They executed 66 deorbiting maneuvers in July and August before concluding the objective on September 11. This assisted in burning fuel and set the satellite to hit Earth 16 years later. The unpredictability of solar activity made it difficult for scientists to accurately estimate exactly when the satellite would hit Earth. The solar activity changes the atmosphere’s density, which affects how much the atmosphere tugs on the satellite. Originally, scientists believed ERS-2 would enter the atmosphere at 10:49 EST. However, it ended up orbiting the planet for an hour.
While this phenomenon was alarming to most due to the disconcerting headlines of satellites hitting Earth, multiple objects this size reenter the atmosphere every year. According to the ESA, the chances of an individual being harmed by space debris every year are less than 1 in 100 billion, which is nearly 1.5 million times lower than the risk of being killed in an accident in any household. It was confirmed by the ESA that no civilians were harmed during the reentry. Because the ERS-2 is well-known among the scientific community, the reentry was highly publicized.
This reentry was only one of the initiatives undertaken by the ESA. The ESA’s mission is to ensure the long-term sustainability of space activities. One of the newest initiatives is the Clean Space initiative, which encourages the advancements of new technologies for more sustainable space missions. The initiative also aims to collaborate with European nations, reducing the overall debris left by the Earth. With space initiatives becoming increasingly innovative, we can hope to uncover more mysteries surrounding space.
