NASA's 600Kg Satellite Is Falling Back to Earth, Is There Any Danger?

A retired NASA satellite weighing around 600 kilograms is expected to re-enter Earth's atmosphere after nearly 14 years in orbit, raising questions about whether people on the ground should be concerned, according to Live Science. Experts say the risk to the public is extremely small, as most of the spacecraft will burn up before reaching the surface. 

What is Van Allen Probe A?

The spacecraft, called Van Allen Probe A, was launched by NASA in August 2012 along with its twin probe. The mission was designed to study the Van Allen radiation belts, zones of energetic charged particles trapped by Earth's magnetic field. 

These belts play a crucial role in protecting the planet from harmful radiation and solar particles. The probes helped scientists better understand "space weather" and how it can affect satellites, astronauts and communication systems on Earth. 

Although the mission was originally planned to last about two years, the spacecraft continued collecting valuable data for nearly seven years before both probes were shut down in 2019 after running out of fuel. 

Why is it crashing now?

According to Live Science, after the mission ended, Van Allen Probe A was left in orbit. Over time, the satellite's orbit gradually decayed due to atmospheric drag. Recent increases in solar activity caused Earth's upper atmosphere to expand slightly, which increased drag and pulled the satellite down faster than expected. 

According to The NYPost, scientists had initially predicted the spacecraft would remain in orbit until around 2034, but the stronger drag means it is returning to Earth several years earlier. 

Chances of injury are very low

NASA and tracking agencies say the spacecraft will largely disintegrate as it enters the atmosphere at high speed. Only a few small pieces made of stronger materials might survive the intense heat. According to NASA, the chance that debris could harm anyone is roughly 1 in 4,200, which experts describe as a very low risk. Another reason for the low danger is geography: about 71 per cent of Earth's surface is covered by oceans, meaning most surviving fragments would likely fall into water or remote areas. 

A common event in spaceflight

Falling satellites may sound dramatic, but re-entries of old spacecraft happen regularly. Most burn up harmlessly in the atmosphere, leaving little or no debris behind. For scientists, the end of Van Allen Probe A marks the final chapter of a mission that significantly improved understanding of Earth's radiation environment and helped make future space missions safer.