Talk:Collision avoidance (spacecraft)

Collision avoidance manoeuvre merge
I merged the Collision avoidance manoeuvre article into this one. If anyone disagrees please discuss why here. Aalox (talk) 11:54, 7 April 2010 (UTC)

Please describe the mathematics of COLA
COLA requires application of interesting mathematics. The covariance matrix associated with a satellite's orbit state is used to construct a three-dimensional error ellipsoid. The extent to which their ellipsoids intersect or overlap gives a conceptual indication of the probability that two orbiting objects will collide (but that's not the whole story -- even if a large ellipsoid completely envelops a smaller one, there's not necessarily a 100% probability of collision). The article really needs to delve into this stuff! 71.219.204.88 (talk) 14:05, 27 August 2013 (UTC)

Description of COLA (for US) 2011
""LIMITING FUTURE COLLISION RISK TO SPACECRAFT

LAUNCH COLLISION AVOIDANCE

Launch collision avoidance (COLA) is the process of actively screening for potential collisions between a launch vehicle and known, tracked, on-orbit objects from liftoff through the end of the launch phase and subsequently taking action to avoid any unacceptable conjunctions. Range safety COLA applies to crewed or crewable space objects, and mission assurance COLA applies to uncrewed objects.

COLA is performed by the Launch Services Program (LSP) at Kennedy Space Center. COLA is not required by LSP; it is performed at the request of the customer. GSFC has requested COLA for all of its missions for the primary purpose of protecting orbiting assets, not the satellite being launched. USAF instructions mandate the operational implementation of launch conjunction assessment and collision avoidance at AF-controlled ranges, and avoidance of crewed conjunctions is mandatory for safety.

LSP obtains launch COLA support from The Aerospace Corporation, which uses a probability-based tool called “Collision Vision” that has extensive heritage on NASA, USAF, and National Reconnaissance Office launches. The use of the tool requires a trajectory ephemeris and covariance at key trajectory event milestones from the contractor. The launch COLA analysis is performed for all separated bodies up through 100 minutes after separation.

Due to the large uncertainties in the launch dispersions (deviations from a planned trajectory), the COLA methodology cannot be reasonably used except for a few orbits after launch.

Finding: The large uncertainties in the launch dispersions (deviations from a planned trajectory) that yield a probability of collision of less than 10^–5 translate to a very low return on investment in launch collision avoidance (COLA), and funds could probably be used more effectively in some other area of debris mitigation. However, in the event of a collision during launch, the political realities of potentially having done nothing probably mean that the use of COLA needs to continue, especially for crewed launches."" Limiting Future Collision Risk to Spacecraft: An Assessment of NASA's Meteoroid and Orbital Debris Programs (2011), chapter 9 - raises the question - what does COLA cost ? - Rod57 (talk) 13:39, 25 July 2020 (UTC)