Space Surveillance Telescope

The Space Surveillance Telescope (SST) is a military telescope for detecting, tracking and cataloguing satellites, near-Earth objects and space debris.

SST achieved first light in 2011 at the White Sands Missile Range, New Mexico, United States. In 2017, SST was dismantled and moved to the Harold E. Holt Naval Communication Station, Exmouth, Western Australia. From there it will observe the Southern Celestial Hemisphere and collect data for the US Space Surveillance Network. SST achieved first light in Australia on March 5, 2020. SST entered initial operational capability on October 4th, 2022 and is operated by the Royal Australian Air Force, 1 Remote Sensor Unit under the command and control (C2) of the U.S. Space Force.

Purpose

SST enables the military to better track and identify objects and threats in space including space debris, as well as predict and avoid potential collisions. Whether it is space traffic management or the protection of critical space-based capabilities, SST will improve the ability to maintain real-time awareness of the space domain to facilitate the broader needs of both the U.S. and Australia. The discovery and tracking of space debris is noted as a growing problem in the 21st century. One problem is that among the 20-30 thousand large objects in orbit that are tracked, and an estimated 100 million debris as small as paint flecks, it is difficult to find objects that are harder to track than the big objects, but big enough to be harder to shield against if they collide with a space asset. Even paint flecks are known to cause damage because of the extreme speeds at which objects travel in orbit. In other words, there are objects too big to easily shield against, but too small to track. Another concern is the Kessler syndrome, a chain reaction of collisions, creating far more space debris dangerous for working satellites. Another concern are near-Earth asteroids, and the SST can detect these objects as part of its mission.

Design

The SST was sponsored by DARPA and designed by the Massachusetts Institute of Technology Lincoln Laboratory.

SST has a 3.5 meter (138″) aperture mirror. Two noted design features include a Mersenne-Schmidt type optics and curved CCD. The large curved focal surface array sensors are considered to be an innovative design. It encompasses improvements in detection sensitivity, has short focal length, wide field of view, and improvements in step-and-settle abilities. DARPA Privacy and Security notice #2
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SST detects, tracks, and can discern small, obscure objects, in deep space with a "wide field of view system". It is a single telescope with the dual abilities. First the telescope is sensitive enough to allow for detection, also, of small, dimly lit objects (low reflectivity). Second it is capable of quickly searching the visible sky. This combination is a difficult achievement in a single telescope design.

It is a Mersenne-Schmidt design with an F/1.0 aperture and a 3.5 meter primary mirror. It uses an array of charge-coupled device (CCD) sensors, arranged on a curved focal plane array. The SST mount uses an advanced servo-control technology, that makes it one of the quickest and most agile telescopes of its size. It has a field of view of 6 square degrees and can scan the visible sky in 6 clear nights down to apparent magnitude 20.5. These features allow the system to conduct multiple searches throughout the night, including the entire geostationary belt within its field.

As a telescope system, it can give precise locations of discovered objects, extrapolate the course of the object, and indicate the objects stability.

The SST is notable in the number of observations it makes and is currently listed by the Minor Planet Center as the world record holder for making the most observations in a single year. In 2015 it made a record 6.97 million observations, significantly more than any other telescope, including Pan-STARRS which is currently in second place, having recorded 5.25 million observations in its best year so far (2014).

See also

*United States Space Surveillance Network
* List of largest optical reflecting telescopes
*Space debris
* Near-earth objects
*Satellites
*Asteroid impact prediction

References

Notes

External links

Asteroid Detection with the Space Surveillance Telescope

{{United States Missile Defense

Optical telescopes
United States Space Surveillance Network
Military equipment introduced in the 2010s