ILRS Mission Priorities as of February 4, 2020

22-Mar-2020
Michael Pearlman - ILRS Central Bureau

At the moment the ILRS network is faced with severe limitations in its tracking capacity. A number of stations have been closed and others have reductions in their operation periods. We need to make some changes in our tracking priorities to best accommodate the situation. Above all, however, is the safety of our personnel.

Considerations:

  • We need to stress the importance of the geodetic satellites since their data are the basis of the reference frame and since they are passive (no alternative tracking systems), we want to maintain continuity of their orbits (so we don't lose them);
  • Altimeter satellites can get by with a couple of passes each week from each station;

We ask the stations to adjust their operating schedules as possible using the following priorities:

  • Geodetic 1: LAGEOS 1 and 2, and LARES (Reference Frame)
  • Geodetic 2: Starlette, Stella, Larets, BE-C, Ajisai, Etalon 1 and 2 (avoid loss of contact)
  • Altimeter: Jason-3, ICESat (a couple of passes per week on each is sufficient)
  • Other LEO satellites: within the available tracking schedule; (one pass per satellite per shift is sufficient)
  • GNSS satellites within the available tracking schedule (try to sample each constellation)

Current high priority GNSS satellites:

  • BeiDou3-M2, 3-M3, 3-M9, and 3-M10
  • Galileo-102, -202, -209, -210
  • GLONASS-131, -134, -138, and -139

If time permits tracking of any additional GNSS satellites, selection of targets should be determined at the convenience of the station.Hopefully the need for this abbreviated schedule will not be required for very long.

If you have any questions, please contact Mike Pearlman.

The ILRS has ordered its tracking priority list according to satellite orbital parameters and special project needs.Tracking priorities have been ordered as follows:

  • Priorities decrease with:
    • increasing orbital altitude; and
    • increasing orbital inclination (at a given altitude).
  • Priority of some satellites may then be increased to intensify support for:
    • active missions (such as altimetry);
    • special campaigns (such as IGEX 98); or
    • post-launch intensive tracking phases; and
  • Some slight reordering may be done to give higher priority to missions with increased importance to the analysis community.

Stations may adjust priorities to accommodate local conditions such as system capabilities, weather, and special program interests.

The ILRS priority list includes several high priority GNSS satellites. All of the remaining GNSS satellites, included on the Current or Past/Other satellites lists, can be tracked by the stations on an as time available basis; selection of targets should be determined by the stations for data yield, but stations are asked to try to diversify among all three constellations because we need some data on all three.

Satellite sponsors request for tandem mission satellites be tracked on alternate passes.

Related Links:

Current Priority List


Priority Mission ILRS
Name		 COSPAR
ID		 SIC Sponsor Altitude
(km)		 Inclination
(degrees)		 Comments
1 GRACE-FO-1/2 gracefo1
gracefo2		 1804701
1804702		 0123
0124		 NASA JPL and the German Research Centre for Geosciences (GFZ) 500 89 1-month campaign
2 ICESat-2 icesat2 1807001 6873 NASA 496 92 Restricted tracking; authorization required
3 CryoSat-2 cryosat2 1001301 8006 ESA 450-720 92  
4 PAZ paz 1802001 2501 HISDESAT 514 97.44  
5 TanDEM-X tandemx 1003001 6202 Infoterra/ DLR/GFZ/CSR 514 98 Tandem with TerraSAR-X
6 TerraSAR-X terrasarx 0702601 6201 Infoterra/ DLR/GFZ/CSR 514 97.44 Tandem with TanDEM-X
7 SNET-4 snet4 1801409 6207 Technische Universität Berlin 600 97.6  
8 SNET-3 snet3 1801408 6206 Technische Universität Berlin 600 97.6  
9 SNET-2 snet2 1801407 6205 Technische Universität Berlin 600 97.6  
10 SNET-1 snet1 1801410 6204 Technische Universität Berlin 600 97.6  
11 TechnoSat technosat 1704205 6203 Technische Universität Berlin 600 97.6 - 97.9 degrees ±7.2 arcmin 3-month campaign
12 STSAT-2C stsat2c 1300301 3804 MEST, KAIST 300 - 1500 80  
13 Sentinel-3B sentinel3b 1803901 8011 ESA/EUMETSAT 814.5 98.65

Restricted tracking; authorization required
14 Sentinel-3A sentinel3a 1601101 8010 ESA/EUMETSAT 814.5 98.65

Restricted tracking; authorization required
15 Swarm-A/C swarma
swarmc		 1306702
1306703		 8007
8009		 ESA 460
530		 88.35
88.95		  
16 Swarm-B swarmb 1306701 8008 ESA 460 88.35  
17 KOMPSAT-5 kompsat5 1304201 3803 KARI 550 96.7  
18 SARAL saral 1300901 3201 CNES and ISRO 814 98.55  
19 HY-2B hy2b 1808101 2208 China 971 98.55  
20 HY-2A hy2a 1104301 2201 China 971 99.35  
21 Jason-3 jason3 1600201 4379 NASA, CNES, Eumetsat, NOAA 1,336 66.0  
22 Geo-IK-2 geoik2 1603401 5561 JSC ISS 943.5 - 973.5 99.47  
23 Larets larets 0304206 5557 IPIE 691 98.204  
24 Starlette starlette 7501001 1134 CNES 815-1,100 49.8  
25 Stella stella 9306102 0643 CNES 815 98.6  
26 LARES lares 1200601 5987 ASI 1,450 69.5  
27 LAGEOS-2 lageos2 9207002 5986 ASI/NASA 5,625 52.6  
28 LAGEOS-1 lageos1 7603901 1155 NASA 5,850 109.8  
29 Etalon-1 etalon1 8900103 0525 Russia 19,100 65.3  
30 Etalon-2 etalon2 8903903 4146 Russia 19,100 65.2  
31 Ajisai ajisai 8606101 1500 JAXA 1,485 50  
32 GLONASS-131 glonass131 1301901 9131 Russia 19,140 65  
33 Galileo-102 galileo102 1106002 7102 ESA 23,220 56  
34 BeiDou-3M2 beidou3m2 1706902 2014 China Satellite Navigation Engineering Center 21,500 55  
35 GLONASS-134 glonass134 1407501 9134 Russia 19,140 65  
36 Galileo-202 galileo202 1405002 7202 ESA 23,220 56  
37 BeiDou-3M3 beidou3m3 1801802 2015 China Satellite Navigation Engineering Center 21,500 55  
38 GLONASS-138 glonass138 1805301 9138 Russia 19,140 65  
39 Galileo-209 galileo209 1507901 7209 ESA 23,220 56  
40 BeiDou-3M9 beidou3m9 1802901 2019 China Satellite Navigation Engineering Center 21,500 55  
41 GLONASS-139 glonass139 1808601 9139 Russia 19,140 65  
42 Galileo-210 galileo210 1603002 7210 ESA 23,220 56  
43 BeiDou-3M10 beidou3m10 1802902 2020 China Satellite Navigation Engineering Center 21,500 55  
44 IRNSS-1B irnss1b 1401701 3302 ISRO 42,293 31  
45 QZS-3 qzs3 1704801 1583 Cabinet Office, Government of Japan 36,000 0  
46 QZS-2 qzs2 1702801 1582 Cabinet Office, Government of Japan 32,000-40,000 km 45  
47 QZS-4 qzs4 1706201 1584 Cabinet Office, Government of Japan 32,000-40,000 km 45  
48 IRNSS-1I irnss1i 1803501 3309 ISRO 35,786 29  
49 IRNSS-1F irnss1f 1601501 3306 ISRO 35,786 29  
50 IRNSS-1E irnss1e 1600301 3305 ISRO 35,786 29  
51 IRNSS-1D irnss1d 1501801 3304 ISRO 42,293 30.5  
52 IRNSS-1C irnss1c 1406101 3303 ISRO 42,293 5  
53 QZS-1 qzs1 1004501 1581 Cabinet Office, Government of Japan 32,000-40,000 45  
54 Beacon-C beaconc 6503201 0317 NASA 950-1300 41  

Lunar Tracking Priorities

Priority Retroreflector Array ILRS
Name		 COSPAR
ID		 SIC Sponsor Altitude(km)
1 Apollo15 apollo15 0000103 N/A NASA 356,400
2 Apollo11 apollo11 0000100 N/A NASA 356,400
3 Apollo14 apollo14 0000102 N/A NASA 356,400
4 Luna21 luna21 0000101 N/A Russian Federation 356,400
5 Luna17 luna17 0000104 N/A Russian Federation 356,400