Star's magnetic fields to be studied

NASA to launch SUMI sun mission An experimental instrument will be launched on a sounding rocket Thursday to study magnetic fields on the sun, US space officials said. NASA said the Solar Ultraviolet Magnetograph Investigation will study the sun's chromosphere A thin layer of solar atmosphere sandwiched between the visible surface, photosphere and its atmosphere, the corona.
"What's novel with this instrument is that it observes ultraviolet light, when all the others look at infrared or visible light," Jonathan Cirtain, a solar scientist at NASA's Marshall Space Flight Center in Huntsville, Ala., said Monday in a release. "Those wavelengths of light correspond to the lowest levels in the sun's atmosphere, but SUMI will look at locations higher in the chromosphere."
NASA said understanding the structure of the magnetic fields in this region will help scientists understand how the corona is heated and how the solar wind is formed. It is also an area believed to be where flare accelerated particles originate, so understanding the processes at play in the transition region can help with models to predict such eruptions on the sun.
SUMI will launch from White Sands Missile Range in New Mexico on a Black Brant rocket. The flight will last about eight minutes.
The instrument has flown once before, in July 2010, but experienced a much higher G-force than expected, which broke screws holding the main mirror in place so it could not gather accurate data. The team has now reinforced the mirror, NASA said.