MOUNTAIN VIEW, Calif. — NASA has selected a spacecraft to study the sun’s corona and a cluster of smallsats to monitor turbulence in the solar wind as its next Explorer-class heliophysics missions.
NASA announced Feb. 10 it selected the Multi-slit Solar Explorer (MUSE) and HelioSwarm as its next two heliophysics Medium-Class Explorer, or MIDEX, missions. The two came from a set of five proposals NASA awarded study contracts for in August 2020 to refine their mission designs.
MUSE will operate in Earth orbit, observing the sun at extreme ultraviolet wavelengths to better understand the mechanisms that heat the corona, the tenuous upper atmosphere of the sun, to temperatures in excess of one million degrees Celsius. MUSE will also be able to observe solar flares and coronal mass ejections that contribute to the corona’s high temperature.
“MUSE has two unique and novel telescopes onboard that will allow us to capture images and diagnose the properties of the gases in the hot solar atmosphere at much higher resolution and up to 100 times faster than possible before,” said Bart DePontieu, principal investigator of MUSE at the Lockheed Martin Advanced Technology Center, in a statement. The center, which has operated other space science missions, will manage MUSE.
HelioSwarm will feature a “hub” spacecraft and eight smaller spacecraft deployed from it. Together, they will measure fluctuations in the magnetic field and motions of the solar wind known as solar wind turbulence.
“Turbulence in space helps keep the universe hot, but we know very little about how it works. Many space scientists have waited decades for this mission,” said Harlan Spence of the University of New Hampshire, principal investigator for HelioSwarm, in a NASA video. “I’m also excited about HelioSwarm because of its novel implementation: a swarm of nine HelioSwarm spacecraft, dancing around each other as they orbit, producing shapes and separations needed to reveal space turbulence for the first time.”
HelioSwarm will be managed by NASA’s Ames Research Center and has a projected cost of $250 million. MUSE has a projected cost of $192 million. NASA set a cost cap of $250 million, excluding launch, in the heliophysics MIDEX announcement of opportunity in 2019.
NASA did not announce when either HelioSwarm or MUSE will launch. In the announcement of opportunity, NASA said that the winning missions had to be ready for launch by February 2026.