XMM-Newton On Board Time Wrap-Around Events

 

The table below contains all past CDMU Clock Events (either resets or wrap-around) as well as the next predicted wrap-around.

The current wrap-around period is: 16777408.8 secs (194 days, 04 hours, 23 minutes and 28 seconds), based on a drift factor (secs/count) of: 1.00001149178

The drift factor is not constant and has to be periodically re-evaluated; therefore, the prediction is within a few seconds of the real event (the table will be updated with the correct value after the event, and a new prediction will be made).

A CDMU reset brings the clock counts down to 0. In case of such an event, it will be reported in the table and a new wrap-around prediction will be determined. The reported times for CDMU resets indicate the time when the clocks resumed (although the CDMU problem had occurred earlier).

After a CDMU reset or a wrap-around the Instruments' clocks and the CDMU have to re-synchronized. This is either a manual Procedure or it automatically occurs at Instrument switch-on. The table indicates when the clocks re-sync took place for each event (and the potential impact associated with the delay between on-board clock re-start and Instruments' clocks re-sync).

Please view this PDF File for details on the 2000's resets.

Instruments' Clock Events
No Date & Time Rev Type Impact
44 2020-08-08T07:51:33Z 3784 Predicted wrap-around No science to be scheduled around this time.
Clocks re-sync to be done via manual procedure.
43 2020-01-27T03:28:04Z 3687 Wrap-around Obs 0841481601 affected.
42 2019-07-16T23:04:22Z 3590 Wrap-around Slew observation.
Observation 0841680701 and 0841680601 affected.
41 2019-01-03T18:40:55Z 3492 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
40 2018-06-23T14:17:22Z 3395 Wrap-around Obs 9339500002 skipped.
39 2017-12-11T09:53:47Z 3298 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
38 2017-05-31T05:30:22Z 3200 Wrap-around Obs 9320000005 skipped.
37 2016-11-18T01:06:54Z 3103 Wrap-around Observation 0782530201 affected.
36 2016-05-07T20:43:24Z 3006 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
35 2015-10-26T16:20:01Z 2908 Wrap-around Obs 9290800004 skipped.
34 2015-04-15T11:56:37Z 2811 Wrap-around Obs 0761020101 affected.
33 2014-10-03T07:33:16Z 2713 Reset Obs 0611182401 affected.
32 2014-09-13T19:47:27Z 2704 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
31 2014-03-03T15:24:08Z 2606 Reset Obs 0740830201 affected.
30 2013-10-15T03:29:03Z 2536 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
29 2013-04-03T23:05:44Z 2439 Wrap-around Clocks re-sync via manual procedure.
One slew exposure skipped.
28 2012-09-21T18:42:28Z 2342 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
27 2012-03-11T14:18:41Z 2244 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
26 2011-08-30T09:55:59Z 2147 Wrap-around Obs 0674670101 affected.
25 2011-02-17T05:32:47Z 2049 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
24 2010-08-07T01:09:09Z 1952 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
23 2010-01-24T20:46:32Z 1855 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
22 2009-07-14T16:23:28Z 1757 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
21 2009-01-01T12:00:25Z 1660 Wrap-around Clocks re-sync via manual procedure.
Observation start delayed untill end of re-sync.
20 2008-06-21T07:37:28Z 1563 Wrap-around Clocks re-sync via manual procedure.
Observation start delayed untill end of re-sync.
19 2007-12-10T03:14:32Z 1465 Wrap-around Clocks re-sync via manual procedure.
One EPIC slew observation skipped.
18 2007-05-29T22:51:39Z 1368 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
17 2006-11-16T18:28:47Z 1271 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
16 2006-05-06T14:06:11Z 1173 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
15 2005-10-24T09:43:12Z 1076 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
14 2005-04-13T05:20:32Z 0978 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
13 2004-10-01T00:58:00Z 0881 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
12 2004-03-20T20:35:20Z 0784 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
11 2003-09-08T16:12:49Z 0686 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
10 2003-02-26T11:50:21Z 0589 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
9 2002-08-16T07:27:59Z 0492 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
8 2002-02-03T03:05:40Z 0394 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
7 2001-07-23T22:43:26Z 0298 Wrap-around No operations (ARTEMIS support).
Clocks re-sync at Instrument switch-on on rev 299 (no impact).
6 2001-01-10T18:21:20Z 0200 Wrap-around Idle period.
Clocks re-sync via manual procedure (no impact).
5 2000-06-30T13:59:22Z 0102 Reset CDMU anomaly occurred on Obs 0099020301 (rev 102). Clocks re-sync for OM, EPIC-MOS1 and EPIC-MOS2 performed before re-sumption of science operations in rev 0103.
Clocks re-sync for RGS1, RGS2 and EPIC-PN had problems and was not effective until end of rev 0104. The following observations have, therefore, timing problems for RGS1/2 and EPIC-PN:
  0103 0109970101
  0103 0111020101
  0103 0111020201
  0104 0111130201
  0104 0112650501
  0104 0127110201
  0104 0127120101
  0104 0127160101
4 2000-06-17T16:07:37Z 0096 Reset CDMU anomaly occurred on Obs 0006810101 (rev 96). Obs 0126700801 partially affected. Clocks re-sync effective before resumption of this obs.
3 2000-03-17T15:13:35Z 0050 Reset CDMU anomaly. No obs for rev 50 was performed. Clocks re-sync via manual procedure before start of rev 51 (no impact).
2 2000-03-16T07:38:20Z 0049 Reset CDMU anomaly occurred on Obs 0094810301. No more obs in rev 49 was performed. No clocks re-sync (but see next entry).
1 1999-12-10T08:54:55Z 0000 Reset (Launch) None (nominal reset at Launch)