Revised May 19, 2020
- Simulations of the Rubin Observatory Legacy Survey of Space and Time (LSST) observing cadence and the full 42,000 SpaceX satellite constellation show that as many as 30% of all LSST images would contain at least one satellite trail.
- Nearly every LSST image taken during twilight would be affected by at least one satellite trail.
- Measurements of the brightness of the current LEO satellites indicate that trails would cause residual artifacts in the reduced data, if no mitigations are made.
- SpaceX is on track to darken their Starlink satellites to 7th mag, which would enable removal of artifacts in LSST images.
- The bright main satellite trail would still be present, potentially creating systematics at low surface brightness. This is a challenge for science data analysis, adding significant effort.
The Vera C. Rubin Observatory science community is concerned about the increasing deployment of communications satellite constellations which, if unchecked, could jeopardize the discoveries anticipated from Rubin Observatory when science operations begin in 2022. Because Rubin Observatory is uniquely impacted by these satellite constellations, its science team is taking an active role in pursuing mitigation strategies to reduce the impact of the satellites on Rubin Observatory science.
The Vera C. Rubin Observatory is nearing completion, and its Legacy Survey of Space and Time (LSST) will soon offer an unprecedented, detailed view of the changing sky. Starting in late 2022, Rubin Observatory will employ the 8.4-meter Simonyi Survey Telescope and the 3200 megapixel LSST Camera to capture about 1,000 images of the sky, every night, for ten years. Each image will cover a 9.6 square degree field of view, or about 40 times the area of the full Moon. Because of the telescope's large light-collecting area, each nominal 30-second exposure will reveal distant objects that are about 20 million times fainter than those visible with the unaided eye. This large combination of light-collecting area and field of view on the sky is unprecedented in the history of optical astronomy.
LSST survey images will contain data for about 20 billion galaxies and a similar number of stars, and will be used for investigations ranging from cosmological studies of the Universe to searches for potentially dangerous Earth-impacting asteroids. However, the revolutionary discoveries anticipated from the Rubin Observatory LSST could be significantly degraded by the fast deployment of Low Earth Orbiting (LEO) communications satellite constellations.