NASA's Probe Van Allen A falling back to Earth

The Van Allen Probe A, a NASA spacecraft weighing about 600 kilograms, is falling back toward Earth. Although the exact time and location of the re-entry remain uncertain, experts say the characteristics of its orbit rule out the possibility that the impact could occur in Italy.

According to specialists from the NASA, some fragments of the spacecraft could survive the passage through the atmosphere and reach the ground, but the risk of damage is estimated at about 1 in 4,200, CE Report quotes ANSA.

“From a practical point of view, the re-entry of this probe does not pose a risk to either Italy or Europe because it has a very low orbital inclination, meaning it could only fall along the equatorial belt,” Luciano Anselmo, a space dynamics expert and research associate at the National Research Council of Italy’s Institute of Information Science and Technologies 'A. Faedo', told ANSA.

The probe was launched in August 2012 together with its twin spacecraft, Van Allen Probe B, to study the Van Allen radiation belts surrounding Earth, from which the probes take their name.

Both spacecraft were placed in a highly elliptical orbit, meaning their trajectory took them more than 20,000 kilometers away from Earth before descending to just a few hundred kilometers above the planet, along a plane close to the equator.

“Very few satellites use this type of orbit, and in this case it was necessary to study the Van Allen belts, which are energetic particles surrounding our planet,” Anselmo added.

This trajectory makes it very difficult to predict the exact re-entry location. Current estimates suggest the spacecraft could re-enter around 00:45 tonight, with an uncertainty window of up to 24 hours.

“In fact, it may have already re-entered,” Anselmo said, adding that confirming the exact moment will be difficult because there are few instruments along the equator capable of detecting the event.

It is very likely that the probe will fall into the ocean or remote areas, but there remains a small risk that debris could land in populated regions and cause damage.