Description
A retired NASA satellite will crash into Earth in the next few days, almost 21 years after it was launched. The spacecraft weighs around 300 kg and most of it is expected to burn up during its re-entry into the atmosphere. The US military predicts that the RHESSI (Reuven Ramaty High Energy Solar Spectroscopic Imager) satellite, which was used to study the Sun, would return to Earth around 9:30 p.m. EDT Wednesday (7:00 a.m. Thursday), with an uncertainty of +/- 4 pm "NASA and the Department of Defense will continue to monitor re-entry," a NASA statement said. Most of the spacecraft should burn up as it passes through the atmosphere, although some components should survive re-entry. "The risk of harm to anyone on Earth is low, about 1 in 2,467," NASA said.
After more than 16 years of successful operation since its inception in 2002, RHESSI was decommissioned on August 16, 2018. The detectors were not turned back on after the sixth anneal due to communication problems, according to the space agency.
RHESSI studied solar flares and coronal mass ejections from low-Earth orbit from 2002 to 2018, helping scientists understand the underlying physics of how these strong bursts of energy form. (ALSO READ: NASA Satellite Captures 'Smiling Sun.' Learn the Science Behind It)
The RHESSI data provided crucial information about solar flares and the coronal mass ejections that accompany them. During its mission, RHESSI captured nearly 100,000 X-ray events, allowing scientists to analyze energetic particles from solar flares.
RHESSI has documented the enormous variety in the size of solar flares over the years, from microscopic nanoflares to colossal superflares tens of thousands of times larger and more explosive, the US space agency said.
RHESSI has achieved non-flare results, including improving measurements of the Sun's structure and demonstrating that gamma-ray bursts generated from the top of Earth's atmosphere above thunderstorms are more common than previously thought.
