>What is it?
>The STEREO space weather beacon telemetry mode is a very low rate, highly compressed data stream broadcast by the spacecraft 24 hours per day. These data are used for space weather forecasting.
>The images above are shown in the order of the relative positions of the three viewpoints (post-solar-conjunction), Ahead, Earth, and Behind. For the Heliospheric Imager (HI) images below, the order is reversed to reflect the fact that the HI Ahead telescopes look to the right of the Sun, and those on Behind look to the left. Also, the HI images are not rotated to put solar north up.
the HI Ahead telescopes look to the right of the Sun