Considerations of a Solar Mass Ejection Imager in Low-Earth Orbit

Lecture Notes in Physics 399, 322−328, 1992

Considerations of a Solar Mass Ejection Imager in Low-Earth Orbit

B.V. Jackson
Center for Astrophysics and Space Sciences
University of California San Diego, La Jolla, CA

D.F. Webb
Institute for Space Research, Boston College, MA

R.C. Altrock
Phillips Laboratory/PHS, National Solar Observatory/Sacramento Peak, NOAO, Sunspot, NM

R. Gold
Applied Physics Laboratory, Johns Hopkins University, Laurel, MD

Abstract

We are designing an imager capable of observing the Thomson scattering signal from transient, diffuse features in the heliosphere. The imager is expected to trace these features, which include coronal mass ejections, co-rotating structures and shock waves, to elongations greater than 90° from the Sun from a spacecraft in an ~800 km Earth orbit. The predecessor of this instrument was the zodiacal-light photometer experiment on the HELIOS spacecraft which demonstrated the capability of remotely imaging transient heliospheric structures. The HELIOS photometers have shown it possible to image mass ejections, co-rotating structures and the density enhancements behind shock waves. The second-generation imager we are designing, would have far higher spatial resolution enabling us to make a more complete description of these features from the Sun to 1 AU. In addition, an imager at Earth could allow up to three days warning of the arrival of a solar mass ejection.