URGENT: We will run out of 5-digit catalog numbers at 69999 not 99999, which is estimated to occur around 2026‑07‑12 (we're currently at 69024). At that point, newly cataloged objects will have 6-digit catalog numbers of 100000+ and GP data will not be available for them using the TLE format. CelesTrak developed new formats that removed this limitation (and finally fixed the Y2K problem) in May 2020 and immediately began providing GP data in those formats for software developers. The same limitations apply to the legacy fixed-field SATCAT. Follow @TSKelso on Bluesky for the latest updates, tutorials, and changes as we approach this transition. Spread the word! ‑ TS

SOCRATES Plus

Search Results

CelesTrak

Search parameters:

  • Name(s): Top 10 by Minimum Range
  • Order by Minimum Range
  • Return first 10 items


Data current as of 2026 May 09 18:34:14 UTC

Computation Interval: Start = 2026 May 09 19:00:00 UTC, Stop = 2026 May 16 19:00:00 UTC
Computation Threshold: 5.0 km
Considering: 15,384 Primaries, 31,125 Secondaries (146,485 Conjunctions)
14 SGP4 Propagation Errors
Computation run time: 11h 15m 46.382s

SOCRATES Format Documentation

See notes at bottom of page for data field descriptions

Data
&
Graphs
NORAD
Catalog
Number
Name [Ops Status] Days
Since
Epoch
TCA
(UTC)
Min
Range
(km)
Relative
Speed
(km/sec)
Max
Probability
Dilution
Threshold
(km)
GP Data 41948 CARTOSAT-2D [+] 1.909 2026-05-11 09:44:53.457 0.005 12.205
50 km All 52939 POEM [?] 2.328 9.640E-02 0.002
GP Data 58291 FALCONSAT-10 [+] 0.648 2026-05-10 03:51:47.874 0.013 10.238
50 km All 67837 STARLINK-36649 [+] 0.706 3.569E-01 0.004
GP Data 56103 STARLINK-6096 [+] 3.353 2026-05-12 20:25:23.458 0.018 8.509
50 km All 19210 COSMOS 1953 [?] 3.427 2.515E-01 0.005
GP Data 62459 SDX01 [+] 1.699 2026-05-11 05:25:47.268 0.020 0.000
50 km All 62460 SDX02 [+] 1.763 4.642E-03 0.011
GP Data 41394 COSMOS 2515 [+] 6.889 2026-05-16 09:17:31.872 0.021 14.205
50 km All 65381 STARLINK-35028 [+] 7.024 1.354E-01 0.010
GP Data 56453 STARLINK-5935 [+] 1.695 2026-05-10 17:44:48.372 0.024 15.009
50 km All 44621 VOLGA DEB [-] 1.411 8.325E-02 0.015
GP Data 56154 PIESAT B [+] 1.501 2026-05-10 22:24:39.444 0.028 0.000
50 km All 56155 PIESAT C [+] 1.435 5.588E-03 0.007
GP Data 60578 LEMUR-2-SQUIRRELCOMM [+] 3.322 2026-05-12 19:08:49.153 0.029 14.706
50 km All 52037 MINOTAUR 4 DEB [-] 3.686 2.066E-03 0.017
GP Data 61239 OBJECT B [+] 2.236 2026-05-11 18:59:07.586 0.030 8.124
50 km All 65534 STARLINK-35125 [+] 2.310 1.110E-01 0.008
GP Data 65283 STARLINK-35015 [+] 4.887 2026-05-14 07:12:50.720 0.030 4.458
50 km All 26546 MEGSAT-1 [-] 4.820 1.041E-01 0.008

10 records found

Data Fields:
  • Data: The GP Data button links to a page which provides the GP data used to generate the associated prediction.
  • NORAD Catalog Number: NORAD Catalog Numbers of the two conjuncting objects.
  • Name: SATCAT names of the two conjuncting objects. Operational status of each object is shown in brackets, using the standard CelesTrak SATCAT codes.
  • Days Since Epoch: The number of days from the epoch of the NORAD GP or SupGP (green) element set used to produce the prediction until the time of closest approach for the conjunction.
  • TCA (UTC): Time of closest approach.
  • Min Range (km): The distance between the two conjuncting objects at the time of closest approach.
  • Relative Speed (km/sec): Relative speed of the two conjuncting objects at the time of closest approach.
  • Max Probability: Given fixed spherical object radii and relative distance at the time of closest approach (TCA), the projected covariance ellipse is sized and oriented to produce the maximum probability. For these reports the ratio of major-to-minor axes of the projected covariance ellipse is set using radial, in-track, and cross-track values of 100 m, 300 m, 100 m, respectively. If the combined object radius is greater than the relative distance, the maximum probability will be one; such occurrences are not addressed here. For more details on the maximum probability method, see Dr. Sal Alfano's paper titled "Relating Position Uncertainty to Maximum Conjunction Probability".
  • Dilution Threshold (km): The standard deviation that produces the maximum probability defines the threshold of dilution. A smaller or larger standard deviation will produce a smaller probability. In the case of computing true probability with a smaller standard deviation, the data is of sufficient quality to associate low probability with low risk. For a larger standard deviation, this is not the case and the resulting true probability calculation becomes "diluted." If operating in this dilution region, the recommendation is to obtain better data and reassess the encounter. If time or resources do not permit, then the maximum probability should be used in place of the true probability.
  • SGP4 Propagation Errors: A list of objects which were not screened because their GP data shows they have already decayed (but haven't yet been reflected in the SATCAT) or will decay prior to the end of the computation interval.