A Surprisingly Quiet Sun
Submitted by chandra on Fri, 2010-08-06 11:11In my last entry I described that particles coming out of the Sun -- especially what we call "soft" protons -- can damage the CCDs that we use on-board Chandra to detect X-rays. Because of this, we use a complicated network of on-board, space-based and ground-based monitors to ensure that the ACIS detector doesn't see too many of these protons. When the Sun was active, we often shut down the detector so that no damage would occur. Due to the solar cycle hitting a down phase, called "solar minimum," we haven't had to shutdown the detectors since 2006.