Collision damages Chinese satellite?
August 18, 2021
By Chris Forrester
On August 14th, astrophysicist and satellite tracker Jonathan McDowell, who’s based at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, Tweeted that a small piece of a Russian rocket (officially Object 48078, 1996051Q) had hit a Chinese satellite (Yunhai 1-02) which was damaged on impact.
The Russian Zenit-2 rocket launched back in September 1996 and eight pieces of the rocket have been tracked for years by the US Space Force’s 18th Space Control Squadron (18SPCS).
McDowell says that Object 48078 is likely to be a fragment measuring some 10-50 centimetres across. “I conclude that [the Space Control Squadron] probably only spotted it in the data after it collided with something, and that’s why there’s only one set of orbital data. So, the collision probably happened shortly after the epoch of the orbit. What did it hit?” McDowell wrote in his follow-up Tweet.
“The obvious candidate is Yunhai-1-02, which broke up on Mar 18 for unknown reasons. It will be interesting to compare the orbits of the objects around then. A quick analysis of the [position and velocity] show that Yunhai 1-02 (44547) and debris object 1996-051Q (48078) passed within 1 km of each other at 07.41 UTC Mar 18, exactly when 18SPCS reports Yunhai broke up,” said McDowell.
Yunhai 1-02 somehow carried on despite the incident which happened some 780 kms in space. Amateur space-watchers have detected signals from the satellite although it is far from certain whether the impact affected its core mission or capability.