Mikkel Christensen
A retired NASA spacecraft could soon make an uncontrolled return to Earth years earlier than scientists once predicted.
A retired NASA spacecraft could soon make an uncontrolled return to Earth years earlier than scientists once predicted. Most of the vehicle is expected to burn up during its descent, though some fragments may survive reentry.
According to AOL citing NASA statements, the spacecraft — Van Allen Probe A — weighs about 600 kilograms and could enter Earth’s atmosphere within a roughly 24-hour window around the predicted reentry time.
Mission studying Earth’s radiation environment
NASA launched the Van Allen probes in 2012 to study regions of energetic particles surrounding Earth.
These areas, known as the Van Allen radiation belts, are zones of charged particles trapped by the planet’s magnetic field.
They act as a protective layer that helps shield Earth from harmful solar radiation and other high-energy particles from space.
The twin spacecraft gathered data for years before the mission ended in 2019 when they ran out of fuel.
Solar activity changed the timeline
When the mission concluded, NASA expected the spacecraft to remain in orbit until roughly 2034.
However, increased solar activity during the current solar cycle expanded Earth’s upper atmosphere, creating additional drag on objects orbiting the planet. That effect gradually slowed the spacecraft and pulled it closer to Earth.
According to AOL citing NASA statements, the stronger-than-expected solar activity accelerated the spacecraft’s descent and moved the reentry date forward by several years.
Low but measurable risk
Most of the spacecraft is expected to disintegrate as it plunges through the atmosphere. Still, some components could survive the intense heat of reentry.
NASA estimates the chance of debris injuring a person at roughly 1 in 4,200, which experts say is still a relatively small risk.
Growing concern about orbital debris
The mission planners intentionally allowed the spacecraft to eventually fall back to Earth rather than leaving it indefinitely in orbit, where it could collide with other satellites.
Space debris has become a growing concern as the number of satellites and rocket launches increases. Thousands of inactive spacecraft, rocket stages and fragments already orbit the planet.
Experts say managing how satellites are disposed of at the end of their missions is becoming increasingly important as space activity expands.
Source: AOL
