Issue 124

3 Jul: As noted in the 23 June Flash, Russia launched an Cosmos 2589 (64467) from Plesetsk on an Angara-5 rocket equipped with a Briz-M upper-stage on 19 June. The launch placed Cosmos 2589 into a highly eccentric orbit with the apogee (the point furthest from the Earth) going well beyond the 35,786km altitude used by Geosynchronous satellites (GEO) and the perigee (the point closest to the Earth) less than 35,786km. On 26 June the 18 Space Defense Squadron (this is the team of superstars that puts together the space catalog) noted that Cosmos 2589 released a sub-satellite (Object D, 64527) on ~26 June. Both satellites have since maneuvered and remain in their unusual highly eccentric orbits.

– Timeline

• 19-26 Jun: Cosmos 2589 maintains a 51,109 x 20,270km orbit with an inclination of 1.1°.
  • Object D has yet to be detected.
  • Jim Shell noted: “Cosmos 2589 (is) in a very interesting orbit…the orbit is such that GEO is transited twice a day with each transit of GEO altitude occurring some some 1.25° further to the east with each orbit.” Watch COMSPOC Video.
• 27Jun – 28 Jun: Both Cosmos 2589 and Object D maneuver.
  • Cosmos 2589 increased both its perigee and apogee over 100km. These maneuvers decreased the orbit’s 1.25° eastward progression to ~0.2° west.
  • Object D increased its overall average altitude over 100km. However, Russia increased the apogee by over 200km while limiting the perigee increase to <15km. As a result of these maneuvers Object D now consistently crosses the GEO belt at ~62.0°E & 147.7°E for each orbit.
  • The distances between Cosmos 2589 and Object D range from ~1,100km to ~2,400km.
• 29 Jun – 3 Jul: No detected maneuvers from either satellite.

– Context

• While this is the first instance of Russia launching into this type of orbit from Plesetsk, Russia has used similar highly eccentric orbits previously. Specifically, Express-103 (45985) and Express-AMU7 (50001).
  • Per Bart Hendrickx: “Express-103 and Express-AMU7 moved from very similar super-synchronous transfer orbits to GEO in 2020/2021 and 2021/2022 (see “Orbital Focus” website). For Express-103 this took about six months and for Express-AM7 about three months. As is to be expected, there was a gradual increase in perigee and a gradual decrease in apogee. One exception was an apogee raising burn by Express-AM7 on or before January 6, 2022.”

– Cosmos 2589 is of particular interest due to its potential GEO inspector mission. As noted in the 22 June Flash, excellent research from the aforementioned Bart Hendrickx links Cosmos 2589 with the CNIIHM Insitute which has, in-turn, been linked to Russian inspection/anti-satellite programs.

– As of 5 July it remains unclear if Russia intends to follow a similar maneuver sequence with either Cosmos 2589 or Object D. The maneuvers on 27-29 June did reduce the orbits’ eccentricity while increasing perigee values, however they also increased the apogee…opposite of what is necessary to bring the spacecraft into GEO.

• Other GEO inspector satellites, such as the US GSSAP vehicles and China’s SY-12 01/02, SJ-17, SJ-23, and TJS-3, operate in or near the GEO belt and raise or lower their average altitudes to drift east or west respectively making minor orbital adjustments as their near their intended collection objects of interest to optimize lighting conditions or collect on the desired face of the target satellite.

• It is theoretically possible for Russia to conduct GEO inspection missions from Cosmos 2589 and Object D’s current orbits.
• Per Jim Shell: “Relative velocities at GEO crossing are on the order of ~1.2 km/s…At 1.2 km/s relative rates and picking a range of 50 km and assuming a bus-fixed imaging payload the required slew rate is ~1.4 deg/s — well within the bounds of a reasonable capability. Now let’s consider a bit of Rayleigh resolution criteria….considering a central wavelength of 550 nm, we are looking at a ~12 cm imaging resolution capability given a 25 cm aperture.”
• For anyone interested in more of the details regarding non-RPO satellite imaging Jim wrote a paper for the AMOS conference which you should check out.
• While theoretically possible, operating from the highly eccentric orbit brings significant operational constraints. If Russia intended to conduct some persistent collect either Cosmos 2589 or the sub-satellite would need to plane match with the object of interest, which would come at a high fuel cost.
  • Nathan Parrott & Saber Astro’s Threat Assessment dashboard modelled both an intercept and rendezvous between Cosmos 2589 and Intelsat 39 (44476), a typical Geostationary communications satellite. An intercept (think fly-by) would require ~ 56 m/s of fuel while a rendezvous (with 1° inclination change) would require a whopping 1,150 m/s.
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Editor’s Note: Not to be Captain Obvious, but we need to wait to see what happens in the coming weeks. I anticipate Russia will eventually maneuver Cosmos 2589 and Obj D into GEO but have yet to maneuver in any conclusive way. Should they desire, Russia can conduct imagery collection operations from the current orbit, however RPO with GEO objects will require prohibitive fuel expense. Another possibility is the two satellites may test inspection operations on one another (Russia did this in LEO with their Nivelir tests.) Cosmos 2589 and Object D are currently co-planar (or nearly so) and their orbits are situated to remain over the Eastern Hemisphere and in site of Russian ground control sites. Time will tell. Thank you to Nathan Parrott and Jim Shell for their collaboration and contributions!