This visualization shows the dataset from STEREO-A processed to enhance the visibility of the coronal mass ejection (CME) in entry #3846. The data are combined from the SECCHI instrument, which includes an ultraviolet image of the Sun (EUVI), two coronographs (COR-1 & COR-2), and the wide-angle Heliospheric Imagers (HI-1 & HI-2).
Because the enhancement process for the CME involves computing differences from a number of sequential HI-1 and HI-2 images, the Earth (left side) and Venus (middle) are masked and oversized icons are installed to mark their position. The dark shape on the left of the field of view is created by an occulting tab that was installed to (occasionally) hide the bright Earth in the view.
The little cross markers label three other planets in the view of STEREO. Uranus is almost invisible in the scale of this imagery, but is visible in full-resolution datasets.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 126.96.36.199.0