The European Space Agency (ESA) and NASA today announced their preliminary selections for the instruments that will fly aboard ESA's forthcoming Solar Orbiter satellite, which will orbit the sun closer than ever before.
The satellite, sometimes known as SOLO, will keep tabs on the sun and the space weather it creates from a cozy position next to our star—inside the orbit of Mercury and less than one-fourth the distance from Earth to the sun. (By comparison, NASA and ESA's currently operating Solar and Heliospheric Observatory, or SOHO, is positioned much farther out—roughly 99 percent of the way from the sun to Earth.) SOLO will also provide a rare glimpse of the polar regions of the sun.
Space weather is not as remote a concern as it sounds—it can affect communications satellites as well as disrupt power lines and degrade pipelines here on Earth. As we reported last week, a massive solar belch called a coronal mass ejection (CME) knocked out power to millions in Canada in 1989.
Among the instruments selected for further development: a heliospheric imager to track CMEs much like the one that blasted Earth 20 years ago, and an ion spectrograph to monitor other energetic particles ejected from the sun.
After launch, which may take place as early as 2015, SOLO will spend 3.4 years cruising to its destination before settling into a 150-day elliptical orbit around the sun.
Artist's conception of SOLO courtesy ESA