US space agency NASA has announced a new mission geared towards probing the interstellar space and specifically interstellar clouds in a bid to garner greater understanding about how stars are formed.
The mission is called Colorado High-resolution Echelle Stellar Spectrograph or CHESS for short. CHESS is a sounding rocket payload that will fly on a Black Brant IX suborbital sounding rocket early in the morning of June 27, 2017. CHESS is a spectrograph, which provides information on how much of any given wavelength of light is present.
According to astronomers the interstellar space is filled with vast clouds of neutral atoms and molecules, as well as charged plasma particles called the interstellar medium. These clouds are believed to offer the raw material required for the formation of stars and galaxies. Astronomers believe that by studying these clouds, they will be able to garner further insights in the lifecycle of stars as well as galaxies.
CHESS will be observe Beta Scorpii, which is a hot, brightly shining star in the Scorpius constellation. As light from Beta Scorpii streams toward Earth, atoms and molecules including carbon, oxygen and hydrogen — block the light to varying degrees along the way. Scientists know which wavelengths are blocked by what, so by looking at how much light reaches the space around Earth, they can assess all sorts of details about the space it travelled through to get there. CHESS data provides observations such as which atoms and molecules are present in space, their temperatures and how fast they’re moving.
Using the data provided by CHESS, astronomers will evaluate how the interstellar cloud is structured, which can help them pinpoint where it stands in the process of star formation. It’s still not known exactly how long it takes for this material to be incorporated into new stars. But scientists know dense clouds can pave the way for the collapse at the very beginning of star formation.
The flight of a sounding rocket is a short one; CHESS will fly for about 16 minutes total. Just six-and-a-half of those minutes are spent making observations between 90 and 200 miles above the surface — observations that can only be made in space, above the atmosphere, which the far-ultraviolet light that CHESS observes can’t penetrate. After the flight, the payload parachutes to the ground, where it can be recovered for future flights.
This is the third flight for the CHESS payload in the past three years, and the mission’s most detailed survey yet. The scientists have used each to trial and improve the technology; the upcoming flight sports an upgraded diffraction grating, which reflects light and separates it into its different wavelengths.
By flying rapidly developing instruments on relatively inexpensive sounding rockets, scientists are not only able to acquire high-quality science data, but also test and mature their instruments toward possible spaceflight. According to France, the CHESS instrument serves as a spectrograph prototype for NASA’s LUVOIR concept.