600-pound satellite plummets toward Earth, may hit humans

Not a plane, bird or frog, it’s a 600-pound satellite hurtling toward Earth — and it’s set to make its crash landing tomorrow.

NASA reported on Monday that the retired Reuven Ramaty High Energy Solar Spectroscopic Imager spacecraft, otherwise known as RHESSI, will reenter Earth’s atmosphere on Wednesday after over two decades in orbit.

While most of the satellite is expected to burn up during its descent, some parts have a chance of surviving the fiery return.

“The risk of harm coming to anyone on Earth is low — approximately 1 in 2,467,” the agency said in a statement.

First launched into its low Earth orbit in 2002, RHESSI has observed solar flares and coronal mass ejections that have aided scientists’ investigation into the physics of the sun’s energy bursts.

Using its imaging spectrometer, RHESSI recorded 100,000 X-ray events, according to the agency, as well as gamma-ray images. It marked the first time gamma-ray and high-energy X-ray images of solar flares had been captured.

NASA announced Monday that the satellite would be returning to Earth this week.

RHESSI spacecraft image
After more than two decades in orbit, the RHESSI spacecraft is scheduled to reenter Earth’s atmosphere on Wednesday.
NASA/Goddard Space

Until its decommissioning in 2018 due to “communications difficulties,” the spacecraft also aided the discoveries relating to the sun’s shape and “terrestrial gamma-ray flashes,” which are bursts that occur over lightning storms on Earth.

At 660 pounds, RHESSI is a relatively lightweight satellite compared to the others that have launched into or returned from orbit.

In January, NASA announced a 38-year-old satellite weighing 5,600 pounds would be returning to Earth, following the multiple instances of Chinese rocket debris that reentered the atmosphere in 2022.

RHESSI spacecraft
After launching in 2002, the spacecraft captured X-ray and gamma-ray images of the sun until 2018 when it was decommissioned.

RHESSI satellite
“The risk of harm coming to anyone on Earth is low — approximately 1 in 2,467,” NASA said of the 660-pound satellite.
NASA/Goddard Space

NASA estimated in 2021 that some 27,000 pieces of space junk are floating in orbit — not including the potentially disruptive and destructive debris that remains “too small to be tracked.”

Traveling at an incredibly high velocity, the danger of space junk is reserved mostly for spacecraft in orbit, as there have been no confirmed injuries or deaths as a result of free-falling space debris.

According to NASA, the higher the orbital debris is, the longer it will take to tumble back to Earth. It takes “several years” for debris to return at altitudes of 373 miles (600 kilometers) or less, but centuries for “orbital decay” to occur at 497 miles (800 kilometers).

At 621 miles (1,000 kilometers), “orbital debris will normally continue circling the Earth for a thousand years or more.”