When it launches in 2024, the Space Weather Follow-On (SWFO-L1), will be NOAA's first satellite observatory dedicated exclusively to operational space weather. It will be equipped with instruments that sample the solar wind, provide imagery of coronal mass ejections, and monitor other extreme activity from the Sun in finer detail than before.
SWFO-L1, which will orbit at the Lagrange Point 1 (L-1)—roughly one million miles from Earth toward the Sun—will continue and improve upon the observational monitoring service of NOAA’s Deep Space Climate Observatory (DSCOVR) launched in 2015 and the joint European Space Agency-NASA Solar and Heliophysics Observatory mission launched in 1995, both of which are in extended service.
"Without timely and accurate warnings, space weather events can disrupt nearly every major public infrastructure system, including power grids, telecommunications, aviation and countless GPS-reliant technologies," said Elsayed Talaat, who manages NOAA's space weather mission and is the director of the Office of Projects, Planning and Analysis at NOAA's Satellite and Information Service, which is responsible for the development of the SWFO program.
Forecasters at NOAA's Space Weather Prediction Center (SWPC) in Boulder, Colo., anticipate significant forecast improvements using a suite of five instruments onboard SWFO-L1:
The Solar Wind Plasma Sensor, being built by Southwest Research Institute (SwRI), and the Magnetometer, being built by SwRI and University of New Hampshire in Durham, will succeed and extend DSCOVR's critical measurements that drive our predictions of geomagnetic storms.
The Supra Thermal Ion Sensor, being built by the University of California, will help refine predictions of the timing and strength of storms and improve radiation storm forecasts, with longer lead times.
SWFO will also fly the Naval Research Laboratory’s Compact Coronagraph that will provide long-lead warnings of extreme solar storms. The European Space Agency (ESA) will contribute an X-ray Flux Monitor, counting X-ray photons coming from the Sun to help classify solar flares.
SWFO-L1 will be a relatively small satellite that will launch as a secondary payload with NASA’s Interstellar Mapping and Acceleration Probe (IMAP) heliophysics science mission. SWFO-L1 will add to NOAA’s contingent of space weather satellites, which includes:
- DSCOVR, launched in 2015 as the nation’s first operational observatory in deep space, it is America’s primary warning system for solar magnetic storms and solar wind data. DSCOVR monitors solar wind and magnetic fields at L-1 and also hosts NASA instruments that look at the Earth.
- COSMIC-2, a fleet of six small satellites launched in 2019 that monitors the ionosphere for any harmful effects of solar storms.
- GOES-16 and -17, advanced geostationary satellites, which in addition to being NOAA’s primary weather satellites, also carry instruments that monitor the Sun and locally observe energetic particles and magnetic field—crucial information used in space-weather alerts and warnings.
SWPC’s Doug Biesecker said: “Another improved feature of SWFO-L1 is in its overall craftsmanship. The spacecraft will be built to withstand extreme space weather conditions, allowing for constant monitoring of the Sun. Previous satellite missions were hampered by the harsh space environment.”
NASA is NOAA’s SWFO-L1's flight system procurement agent and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is the lead for SWFO-L1's instrument and spacecraft acquisitions.