Using data from the STEREO spacecraft, researchers at Southwest Research Institute and the National Solar Observatory have released a video of a coronal mass ejection in 2008 swallowing up the Earth.
“The movie sent chills down my spine,” says Craig DeForest of SWRI. “It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live. I felt very small.”
Complex effects appear as the solar wind, traveling at up to a million miles per hour, shifts and changes on its three-day journey to Earth, guided by the magnetic field lines that spiral out from the Sun’s surface.
These include the solar wind piling up at the leading edge of a CME, voids in the interior, long thread-like structures, and rear cusps. Quiet periods show a magnetic disconnection phenomenon called a plasmoid, ‘puffs’ that correlate with in-situ density fluctuations, and V-shaped structures centered on the current sheet — a heliospheric structure in which the polarity of the Sun’s magnetic field changes from north to south.
“For 30 years, we have been trying to understand basic anatomy of CMEs and magnetic clouds, and how they correspond to their source structures in the solar corona,” says Dr Tim Howard of SwRI.
“By tracking these features through the image data we can establish what parts of a space weather storm came from which parts of the solar corona, and why.”
The team used a combination of image processing techniques to generate the images and extract the faint signals from the far brighter foreground and background.
Small ‘blobs’ of solar wind tracked by the team were more than 10 billion times fainter than the surface of the full moon, for example, and 10 thousand times fainter than the starfield behind them.
The video’s here.