Jonathan's Space Pages

Space Object Reentries

Catalog of Space Object Reentries


In this catalog I assess and categorize each reentry of a historical artificial space objects (payloads, rocket bodies, ejected parts but not fragmentation debris) to compare with present disposal standards.

Statistical summary table [NOTE CAVEATS IN CODES.HTML!]

In the table below, rather than estimating casualty risk, we regard reentries of objects with masses greater than a threshold mass M0 as problematic.

For this edition of the table, M0 has been set to 5000 kg. Note that less massive objects, depending on design, may also pose a significant casualty risk.

Explanation of columns for this table

Updated: 2025 Jul 16 1950:57

ReentryStats
CodeDescClauseStar DisposedStar ActivePL DisposedPL ActiveRBPartsTotal freePL Att DispPL Att AcTotal
Disposal consistent with US ODMSP
D-SODown/SO Targeteda1 0 0 2 0 484 18 504 0 0 504
D-DODown/Deorbiteda1 0 0 378 0 702 2019 3099 0 0 3099
D-LANDDown/Landeda1/f 0 0 2093 0 1 0 2094 0 0 2094
D-LEO25Down/LEO Reentry <25yr, Low mass M<M0b 1202 0 3831 0 3392 6266 13489 285 0 13774
D-NL25Down/LEO-crossing <25yr, Low mass M<M0b 0 0 214 0 647 586 1447 2 0 1449
U-LEO25Up/LEO <25yr expected,Low mass M<M0b 18 7969 1473 1269 110 32 2884 9 0 2893
U-NL25Up/LEO-crossing <25yr expected, Low mass M<M0b 0 0 1 0 17 12 30 2 0 32
U-MEO-EMEO Graveyard (ell.)c.I 0 0 23 6 211 107 347 4 0 351
U-MEO-CMEO Graveyard (circ)c.II 0 0 203 95 121 57 476 7 0 483
U-GGYDGEO Graveyardd 0 0 9 588 59 11 667 2 0 669
D-LUNDown/LunarL 0 0 84 0 7 64 155 0 0 155
U-HELHeliocentrica2 0 0 251 40 225 316 832 8 0 840
Subtotal GSubtotal good disposal- 1220 7969 8562 1998 5976 9488 26024 319 0 26343
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Other disposal
D-LEO25MDown/LEO Reentry <25yr, Massive M>M0- 0 0 38 0 106 0 144 3 0 147
D-NL25MDown/LEO-crossing <25yr, Massive M>M0- 0 0 0 0 8 0 8 0 0 8
U-LEO25MUp/LEO <25yr expected, Massive M>M0- 0 0 4 0 4 0 8 0 0 8
D-LEODown/LEO Reentry >25yr- 0 0 49 0 50 85 184 0 0 184
D-NLDown/LEO-crossing Reentry >25yr- 0 0 27 0 45 66 138 1 0 139
U-LEO+Up/LEO >25yr exceeded- 0 0 1311 0 647 505 2463 14 0 2477
U-LEOUp/LEO >25yr expected- 0 0 854 506 222 339 1921 10 0 1931
U-NL+Up/LEO-crossing >25yr exceeded- 0 0 25 0 23 109 157 2 0 159
U-NLUp/LEO-crossing >25yr expected- 0 0 6 0 7 76 89 0 0 89
U-DESTDestroyed- 0 0 9 0 4 3 16 0 0 16
U-GTOCrosses LEO and GEO- 0 0 125 51 365 140 681 3 0 684
U-XMEOViolates MEO rule- 0 0 46 35 5 3 89 0 0 89
U-XGEOCrosses GEO- 0 0 40 0 122 43 205 1 0 206
U-GEOIn GEO- 0 0 733 0 136 118 987 0 0 987
U-CISLCislunar- 0 0 20 7 0 5 32 0 0 32
Subtotal BSubtotal bad disposal- 0 0 3287 599 1744 1492 7122 34 0 7156
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Note: "Good disposal" means good from the point of view of risk for in-orbit debris collisions; can still be very "bad" from the point of view of ground casualty list for massive reentries.

Further caveats on the following items from US ODMSP Section 4-1:

Note: The ESA standard (ESSB-ST-U-007, 2023) and the ISO standard (ISO-24113, 2023) have generally similar requirements to the US standard, although the ISO standard restricts the GEO protected zone to inclinations of less than 15 degrees, and the ESA standard could use some improvements in clarity.