Coverage started 2012 Oct 25
Updated 2012 Nov 9
On 2012 Oct 19, a notice went up on Space Track reporting the breakup of the Breeze-M rocket body used to unsuccessfully launch Telkom 3 and Express-MD2 on 2012 Aug 6:
JFCC SPACE is currently working to characterize the 16 October 2012 break up of a rocket body (Catalog # 38746) and assess the impact of the debris field to objects on orbit. We will continue to provide notification of potential conjunctions and update the Satellite Catalog via established processes.
Figure 1. Initial distribution of TLE orbits at time of first TLEs
The first TLEs for the breakup were released late on Oct 24, showing that the US Space Surveillance Network (SSN) was tracking at least 80 new pieces of debris. The availability of that data allowed some initial analysis to attempt to determine the time of breakup and to investigate possible causes and implications of the event.
As of 2012 Nov 9, there are now 111 pieces of debris from this event (including whatever is left of the original object) with 5 pieces having decayed from orbit.
Loading all of the TLE data into STK and knowing that the breakup occurred on Oct 16, it was possible to use the initial TLEs to find the time of breakup. While the uncertainty of propagating TLEs in a geosynchronous transfer orbit (GTO) backward 8 days would result in large in-track displacements (in other words, the TLEs wouldn't all come together at a point), it was possible to look for the time when most the debris was at the same altitude and the out-of-plane distance was a minimum (since these factors would have smaller uncertainties).
The result of that analysis was that the likely breakup time was around 1631 UTC on 2012 Oct 16. As it turns out, this was right at perigee for the Breeze-M rocket body, which was full of fuel due to its failure before completing its mission. With a perigee altitude of 268 km, it is likely that the cause of the breakup was an explosion was due to atmospheric heating. As of now, there is no data to suggest a close approach with any of the more than 16,000 objects tracked by the SSN at the time of the breakup.
Figure 2. Location of Breeze-M rocket body at likely breakup point
Independent confirmation of the time of breakup was provided by Robert D. Matson from Dr. Robert McNaught, an astronomer at the Siding Springs Observatory in Australia, who captured observations of some of the debris at 1743 UTC.
Figure 3a. Geometry of observations from Siding Springs Observtory
Dr. McNaught provided an animated GIF with three of the images taken of the debris cloud as it passed over Siding Springs Observatory. Each image is a 10-second exposure with 24 seconds between them. These images help give a real sense for the number of debris objects produced by this event.
Figure 3b. Images from Siding Springs Observtory of the passing debris cloud
A Gabbard plot of the debris shows that all of it has about the same perigee altitude but apogee altitudes ranging as high as 5,500 km. This means that the debris from this event will regularly cross the orbits of all satellites in low-Earth orbit (LEO).
Figure 4. Gabbard plot of breakup debrisCurrently, the debris is crossing the ISS orbit at almost right angles in its 50.2° inclination orbit. Unfortunately, the intersection of the two orbits occurs where the debris is at about the same altitude as the ISS (about 405–425 km altitude). Given that JFCC-Space has reported it "is currently tracking over 500 pieces of debris" [Spaceflight Now, "Rocket explosion raises worries over space debris"]—all in similar orbits—this could present an ongoing challenge for ISS operations.
Figure 5. Debris orbits relative to the International Space Station orbit
I will continue to update this page as new information becomes available. — TS
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