Updated on 2026/10/15

OPERATION LOG OF THE SATELLITE SYSTEM

Ordered by UT-Date of Occurrence (new to old).

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2026-07-16 15:27 - 2026-07-17 08:28
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Comment:

- Data missing occurred during the observation of OBSID 203155010 (4U1323-62). This occurred on July 17th during recovery from the data recorder anomaly.
- This issue affect on data quality: the change in Resolve's absolute timing accuracy and the data loss in the following periods (all in TT):
- Resolve Timing accuracy:
2026-07-16T15:34:04 - 2026-07-16T17:05:13
2026-07-16T17:12:56 - 2026-07-16T19:50:00
2026-07-16T20:01:44 - 2026-07-16T21:16:49
2026-07-17T00:04:44 - 2026-07-17T01:30:25
2026-07-17T01:43:04 - 2026-07-17T03:11:21
2026-07-17T03:24:04 - 2026-07-17T06:14:25
2026-07-17T06:21:52 - 2026-07-17T06:22:17
2026-07-17T06:23:52 - 2026-07-17T08:26:41
- Resolve data loss:
2026-07-17T02:29:55 - 2026-07-17T08:27:56
- Xtend data loss:
2026-07-16T15:27:03 - 2026-07-16T17:06:12
2026-07-16T17:09:46 - 2026-07-16T23:46:31
2026-07-17T00:05:45 - 2026-07-17T08:28:02

Observation(s) related to this note:

- 203155010 / 4U1323-62

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2025/8/10 16:45:55 - 2025/8/13 01:07:47
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Comment:

- The GPS signal receiver onboard the satellite unexpectedly rebooted at around 2025-8-10 16:46 during the observation of OBSID 201044010 (IC4329A), and the XRISM clock system was forced to operate in GPS unsynchronized mode that utilizes the quartz clock. During the observation of OBSID 201047010 (ELIAS29), the clock system recovered synchronization to GPS following a recovery operation at approximately 2025-8-10 01:08.
- During GPS unsynchronized mode, error in the absolute time keeps the mission requirement (see Shidatsu et al., 2025, JATIS, 11, 042012).
- Events that are detected during the transition from GPS synchronized to unsynchronized modes are not assigned any time values due to their classification as "bad status".

Observation(s) related to this note:

- 201044010 / IC4329A
- 201047010 / ELIAS29


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2025/03/17 09:49 - 11:44
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Comment:

- Data missing occurred during the observation of OBSID 201052010 (RADIO_ARC). This occurred due to unfavorable weather which caused all data recorder playback operations to be canceled on March 16th, as well as constraints on the data recorder operations the following day. This issue has no effect on data quality except for the data lost in the following periods.
- Resolve: 2025-03-17 10:06:52 - 2025-03-17 10:45:55
- Xtend: 2025-03-17 09:49:11 - 2025-03-17 10:02:43 and 2025-03-17 10:07:07 - 2025-03-17 11:43:48

Observation(s) related to this note:

- 201052010 / RADIO_ARC


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2024-11-16 21:25:00
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Comment:

- The definition of the SAA region has been revised to increase the observation efficiency.
The same definition has been applied to all observations in the screening criteria of the data processes both for Resolve and Xtend, in which the the CALDB version is updated from 20240822 to 20241115.
 
Observation(s) related to this note:
 
- 201049010 / ABELL1413
- All observations to date after the above one.