This series of images (click for the full view!), taken by the Solar and Heliospheric Observatory satellite (SOHO) in August 2015, reveals a tremendous outburst of plasma and magnetic field from the Sun: a coronal mass ejection (CME). If you look closely, you’ll note that as the CME expands from the Sun’s surface, it passes in front of a dot highlighted in yellow. This dot marks the location of a distant background pulsar, PSR B0950+08. In a recent study led by Tim Howard (Southwest Research Institute), a team of scientists studied the change observed in the radio emission of this pulsar as the CME passed by in the foreground. The team used these observations to estimate the CME’s density and magnetic field — measurements that can tell us more about the nature of the magnetic field in the Sun’s corona and the solar wind.
You can check out the animation of this CME, also taken with SOHO’s LASCO instrument, below (the CME starts around 20 seconds in), or you can find out more from the original paper!
T. A. Howard et al 2016 ApJ 831 208. doi:10.3847/0004-637X/831/2/208