The structure of streamer blobs

Abstract

We have used Sun-Earth Connection Coronal and Heliospheric Investigation observations obtained from the STEREO A and B spacecraft to study complementary face-on and edge-on views of coronal streamers. The face-on views are analogous to what one might see looking down on a flat equatorial streamer belt at sunspot minimum, and show streamer blobs as diffuse arches gradually expanding outward from the Sun. With the passage of time, the legs of the arches fade, and the ejections appear as a series of azimuthal structures like ripples on a pond. The arched topology is similar to that obtained in face-on views of streamer disconnection events (including in/out pairs and streamer blowout mass ejections), and suggests that streamer blobs have the helical structure of magnetic flux ropes. © 2009. The American Astronomical Society.