The mission is named for George Carruthers, an engineer and solar physicist who developed an ultraviolet camera placed on the Moon by the Apollo 16 astronauts in 1972. This camera captured the first view of the geocorona, a term coined by Carruthers himself.
The 531-pound (241-kilogram) Carruthers observatory was built by BAE Systems, with instruments provided by the University of California Berkeley’s Space Sciences Lab.
There’s a lot for scientists to learn from the Carruthers mission, because they know little about the exosphere or geocorona.
“We actually don’t know exactly how big it is,” said Lara Waldrop, the mission’s principal investigator from the University of Illinois Urbana-Champaign. “We don’t know whether it’s spherical or oval, how much it changes over time or even the density of its constituent hydrogen atoms.”
What scientists do know is that the exosphere plays an important role in shaping how solar storms affect the Earth. The exosphere is also the path by which the Earth is (very) slowly losing atomic hydrogen from water vapor lofted high into the atmosphere. “This process is extremely slow at Earth, and I’m talking billions of years. It is certainly nothing to worry about,” Waldrop ensures.
This image illustrates the location of the Sun-Earth L1 Lagrange point, where IMAP, Carruthers, and SWFO-L1 will operate.
Credit:
NOAA
The final spacecraft aboard Wednesday’s launch is the world’s first operational satellite dedicated to monitoring space weather. This $692 million mission is called the Space Weather Follow On-L1, or SWFO-L1, and serves as an “early warning beacon” for the potentially devastating effects of geomagnetic storms, said Irene Parker, deputy assistant administrator for systems at NOAA’s National Environmental Satellite, Data, and Information Service.
NOAA’s previous satellites peer down at Earth from low-Earth orbit or geosynchronous orbit, gathering data for numerical weather models and tracking the real-time movement of hurricanes and severe storms. Until now, NOAA has relied upon a hodgepodge of research satellites to monitor the solar wind upstream from Earth. SWFO-L1, also built by BAE Systems, is the first mission designed from the start for real-time, around-the-clock solar wind observations.