What happened

New orbital data have produced sharply different outcomes for the two Rassvet-3 spacecraft identified earlier in October as approaching re-entry.

Rassvet-3 No. 23, NORAD 100089, had fallen to roughly 221 km by 20 October after spending about three months without sustained orbit raising. Public tracking subsequently showed a clear reversal. The spacecraft began climbing around 20-21 October and, after a gap in published catalogue elements, reappeared on 29 October in an approximately 291 by 300 km orbit, with an average altitude near 296 km. The independent Rassvet tracker findrassvet.ru calculated that this represented an average rise of at least about 8.6 km per day across the data gap.

Rassvet-3 No. 17, NORAD 100083, followed the opposite trajectory. It continued descending rapidly through late October after never establishing sustained orbit raising. On 29 October the independent tracker placed it around 174 km and expected imminent re-entry. Ukrainian reporting citing orbital monitoring said the spacecraft re-entered and burned up in the atmosphere on 30 October.

The development updates LAT-RU-RAS-0020, which recorded both No. 17 and No. 23 as decaying below roughly 260 km and facing possible late-October or early-November re-entry. The forecast proved correct for No. 17 but not for No. 23, whose renewed manoeuvring materially changed its trajectory.

Evidence and limitations

Confidence: High that No. 23 resumed orbit raising. Public orbital elements for NORAD 100089 on 29 October show a 291 by 300 km orbit, independently confirming that it had climbed substantially from the approximately 221 km minimum reported around 20 October. The abrupt reversal is consistent with active propulsion rather than passive orbital evolution.

The exact sequence of No. 23’s manoeuvres cannot be reconstructed from public data because catalogue elements were unavailable for part of the climb. Its recovery to approximately 296 km also does not establish that it will reach the approximately 508 km intermediate orbit occupied by most of the production constellation, or that all spacecraft systems are functioning normally.

Confidence is moderate to high that No. 17 re-entered on 30 October. Multiple reports describe the spacecraft as having left orbit after its rapid terminal decay, and the trajectory immediately beforehand was consistent with imminent atmospheric entry. At publication, however, a precise independently published re-entry epoch and location were not available in the sources reviewed. The record therefore does not assign a specific time or geographic re-entry point.

Assessment

The divergent outcomes are important because they show that low altitude did not necessarily imply an irreversible spacecraft failure. No. 23 appears to have retained or recovered sufficient propulsion capability to arrest a decay that had brought it close to atmospheric loss. That materially corrects the earlier expectation that both low-flying July spacecraft were likely to re-enter within weeks.

No. 17 nevertheless becomes the second serial Rassvet-3 spacecraft reported lost after failing to raise its orbit, following No. 4 from the March batch, which re-entered in June. The loss provides another observed reliability data point for the production constellation, although two failures are insufficient to establish a broader failure rate for the spacecraft design.

No. 23’s recovery is arguably the more technically informative event. If it continues climbing, it would demonstrate that at least one spacecraft can resume substantial orbit raising after spending months at unusually low altitude. Continued tracking will show whether the recovery is sustained and whether No. 23 ultimately joins the main Rassvet orbital group.

Why it matters

The episode demonstrates why Rassvet deployment should be assessed from continuing orbital observations rather than one-time altitude snapshots or projected re-entry dates. Electric-propulsion orbit raising can evolve over long periods, and a spacecraft apparently close to loss can change status if manoeuvring resumes.

For constellation accounting, No. 17 should now be treated as a reported loss, while No. 23 should no longer be treated as an imminent re-entry candidate. The remaining questions are whether No. 23 continues toward the approximately 508 km group and whether the programme discloses any explanation for the very different behaviour of the two spacecraft.

Sources