NASA: Spacecraft reenters atmosphere on Wednesday; no one will be harmed 1 in 2,467

 

The decommissioned NASA Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) spacecraft is scheduled to reenter the Earth's atmosphere in April, about 21 years after launch. RHESSI studied solar flares and coronal mass ejections from its low-Earth orbit from 2002 to 2018, assisting scientists in understanding the underlying physics of how such strong bursts of energy are formed. 

The Department of Defense anticipated the 660-pound spacecraft would reenter the atmosphere at around 9:30 p.m. EDT on Wednesday, April 19, with an uncertainty of +/- 16 hours as of Monday, April 17. NASA and the Defense Department will continue to track reentry and provide updates. 

NASA anticipates that the majority of the spacecraft will burn up as it travels through the atmosphere, but some components will survive reentry. The likelihood of someone on Earth being harmed is low - about 1 in 2,467. 

The spacecraft took off on an Orbital Sciences Corporation Pegasus XL rocket with the objective of imaging the high-energy electrons that convey a major portion of the energy released in solar flares. It accomplished this using only one device, an image spectrometer that captured X-rays and gamma rays from the Sun. Prior to RHESSI, no gamma-ray or high-energy X-ray photographs of solar flares have been obtained. 

RHESSI data gave critical information regarding solar flares and their related coronal mass ejections. Within minutes, these explosions release the energy equivalent of billions of megatons of TNT into the solar atmosphere, causing disruptions in electrical systems on Earth. Understanding them has proven difficult. 

RHESSI captured almost 100,000 X-ray events during its mission, allowing scientists to analyze the energetic particles in solar flares. The imager assisted researchers in determining the frequency, location, and movement of the particles, which allowed them to establish where the particles were being accelerated. 

RHESSI has documented the vast variety in solar flare size throughout the years, from microscopic nanoflares to giant superflares tens of thousands of times larger and more explosive. RHESSI also improved measurements of the Sun's structure and demonstrated that terrestrial gamma-ray flashes - bursts of gamma rays emitted from high in Earth's atmosphere above lightning storms - are more common than previously assumed. 

NASA terminated RHESSI after 16 years of service due to communication issues with the satellite. NASA Small Explorers mission RHESSI was managed and controlled by NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

By Covenant