SOCRATES

Top 10 Conjunctions
by Maximum Probability

Data current as of 2009 Jan 07 02:00 UTC

Computation Interval: Start = 2009 Jan 07 00:00:00.000, Stop = 2009 Jan 14 00:00:00.000
Computation Threshold: 5.0 km
Considering: 2,937 Primaries, 11,758 Secondaries (11,710 Conjunctions)

See notes at bottom of page for data field descriptions

 
Action NORAD
Catalog
Number		 Name Days
Since
Epoch		 Max
Probability		 Dilution
Threshold
(km)		 Min
Range
(km)		 Relative
Velocity
(km/sec)
Start
(UTC)		 TCA
(UTC)		 Stop
(UTC)
33399 SOYUZ-TMA 13 1.426 1.000E+00 0.000 0.000 0.000
33443 PROGRESS-M 1M 1.426 2009 Jan 07 00:00:00.000 2009 Jan 07 00:00:00.000 2009 Jan 14 00:00:00.000
15986 COSMOS 1677 1.326 1.556E-02 0.023 0.033 14.321
31803 FENGYUN 1C DEB 29.235 2009 Jan 07 20:45:42.865 2009 Jan 07 20:45:43.214 2009 Jan 07 20:45:43.564
27450 IRIDIUM 97 5.150 7.677E-03 0.029 0.041 14.825
30392 FENGYUN 1C DEB 5.270 2009 Jan 11 17:33:44.466 2009 Jan 11 17:33:44.803 2009 Jan 11 17:33:45.140
24950 IRIDIUM 31 2.052 2.146E-03 0.077 0.109 14.634
12792 SL-8 R/B 2.304 2009 Jan 08 11:47:46.582 2009 Jan 08 11:47:46.924 2009 Jan 08 11:47:47.265
09903 METEOR 1-27 5.668 1.200E-03 0.085 0.120 13.335
30628 FENGYUN 1C DEB 5.546 2009 Jan 11 14:29:25.008 2009 Jan 11 14:29:25.383 2009 Jan 11 14:29:25.758
Action NORAD
Catalog
Number		 Name Days
Since
Epoch		 Max
Probability		 Dilution
Threshold
(km)		 Min
Range
(km)		 Relative
Velocity
(km/sec)
Start
(UTC)		 TCA
(UTC)		 Stop
(UTC)
05104 ISIS 2 1.332 1.068E-03 0.503 0.712 13.920
21107 COSMOS 2132 1.963 2009 Jan 07 20:28:31.459 2009 Jan 07 20:28:31.815 2009 Jan 07 20:28:32.170
23465 FAISAT 6.340 1.049E-03 0.039 0.056 2.361
31555 FENGYUN 1C DEB 9.782 2009 Jan 13 00:31:21.932 2009 Jan 13 00:31:24.050 2009 Jan 13 00:31:26.168
11962 METEOR 2-6 4.662 1.002E-03 0.093 0.131 14.831
30905 FENGYUN 1C DEB 19.966 2009 Jan 10 16:55:55.081 2009 Jan 10 16:55:55.418 2009 Jan 10 16:55:55.755
16969 NOAA 10 1.630 4.375E-04 0.111 0.157 2.289
29084 DMSP 5D-2 F11 DEB 2.688 2009 Jan 07 22:20:07.966 2009 Jan 07 22:20:10.149 2009 Jan 07 22:20:12.332
10967 SEASAT 1 4.802 3.827E-04 0.334 0.473 14.886
06966 SL-8 R/B 5.224 2009 Jan 11 02:12:32.654 2009 Jan 11 02:12:32.988 2009 Jan 11 02:12:33.323
 
Data Fields:
  • Action: The Analysis button links to a page which provides a capability to build an interactive 3-D STK/CAT (Conjunction Analysis Tools) scenario detailing the conjunction.
  • NORAD Catalog Number: NORAD Catalog Numbers of the two conjuncting objects.
  • Name: Common names of the two conjuncting objects.
  • Days Since Epoch: The number of days from the epoch of the NORAD two-line element set used to produce the prediction until the time of closest approach for the conjunction.
  • 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 to one (AR=1, no orientation is necessary). If the combined object radius is greater than the relative distance, the maximum probability will be one; such occurrences are not addressed here.
  • 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.
  • Min Range (km): The distance between the two conjuncting objects at the time of closest approach.
  • Start (UTC): Time when the two conjuncting objects come within the computation threshold from each other.
  • TCA (UTC): Time of closest approach.
  • Stop (UTC): Time when the two conjuncting objects move beyond the computation threshold from each other.
  • Relative Velocity (km/sec): Relative velocity of the two conjuncting objects at the time of closest approach.
TLE Data Space Data
Current
Archives
Documentation 		GPS
EOP
Space Weather
SATCAT Columns
Boxscore Software
SOCRATES
Dr. T.S. Kelso [TS.Kelso@celestrak.com]
Last updated: 2009 January 7 04:01:27 UTC
Accessed 45,575 times since 2000 December 16
Current system time: 2009 January 7 04:48:42 UTC