For Scientists: The Long-Term Plan

This is the current Long-Term Plan (LTP) for IXPE. The Science Advisory Team requested that transient targets be added when and if they become bright. At such time, the LTP will be adjusted, attempting to minimize the impact on the overall plan; however, nothing is guaranteed. The current LTP can accommodate the addition of approximately a half-dozen transients. Should there be a lack of transients in the coming year, additional time and/or targets will be added to the plan.

IXPE is telemetry limited for bright sources and this requires that observations be handled slightly differently from the way most X-ray missions operate. If IXPE is observing a bright source that could potentially fill on-board storage, we shall divide the observation into multiple segments.


SG: This is a segment number. If it is zero, then the observation has not been segmented.

Name: This is a common name for the target.

Start: The Year-Month-Day the observation will begin. The observations ends just before the next target begins.

buffer: This is an estimate as to how much data will stll be on the spacecraft when the observation ends in MB. The on-board storage can hold just over 5500 MB and when planning we keep this number below 4000 MB.

SG Name Start buffer
2Her X-12022-02-22 2873.4
24U 0142+612022-02-24 2266.3
1Sgr A complex2022-02-27 704.1
2Crab2022-03-07 3921.0
0Mrk 5012022-03-08 3655.5
2Sgr A complex2022-03-10 754.3
04U 1626-672022-03-23 201.2
0Mrk 5012022-03-26 0.0
0GS 1826-2382022-03-28 89.9
0S5 0716+7142022-03-31 0.0
1Vela Pulsar2022-04-05 0.0
0Vela X-12022-04-15 2876.7
2Vela Pulsar2022-04-21 792.7
0Cyg X-22022-05-01 2581.1
01ES 1959+6502022-05-03 2560.6
0Mrk 4212022-05-04 3134.0
0BL Lac2022-05-06 1479.7
1MCG-5-23-162022-05-14 1261.9
0Cyg X-12022-05-15 3668.0
2MCG-5-23-162022-05-21 1706.6
03C 454.32022-05-30 1270.7
03C 2732022-06-01 832.6
0Mrk 4212022-06-04 1410.9
01ES 1959+6502022-06-06 1390.9
0Mrk 4212022-06-06 1971.9
03C 2732022-06-08 1533.9
03C 2792022-06-11 1096.4
03C 454.32022-06-13 659.1
01ES 1959+6502022-06-15 638.0
03C 2792022-06-16 200.5
0Tycho2022-06-18 0.0
0Cen A2022-07-05 0.0
0Mrk 5012022-07-07 0.0
0GX 301-22022-07-09 0.0
0Circinus galax2022-07-14 0.0
0SN 10062022-07-27 0.0
0X Persei2022-08-16 0.0
0MSH15-522022-08-21 0.0
01RXS J170849.02022-09-17 0.0
0GX9+92022-10-07 0.0
0GRS 1915+1052022-10-09 0.0


ToOs will cause planned times to shift around. Plan only covers time up to the end of Sep.

Currently the plan does not include observations of J0211+1051, IC 4329A and 1ES 0229+200. These will be added as the year progresses.

An attempt will be made to start Cyg X-1 on May 15, to facilitate coordinated observations with XL-Calibur.

+ NASA Privacy, Security, Notices | Last Updated: March 08, 2022 | Author/Curator: Mitzi Adams, mitzi.adams @