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This is the latest long-term schedule. Observations have been sorted into one-week intervals, taking into account solar, time, roll, and other constraints. It is our intent to follow this schedule. However, targets which are not constrained may well be moved forward or back in time to fill requirements of the short-term schedules. Targets of opportunity and any instrument or spacecraft anomalies may also cause observing times of targets to shift. This long-term schedule is our present estimate of future order of observations. Please be aware of the uncertainties.
Also notice that targets have been allotted to one-week intervals to fill only about half of real-time. This figure is significantly less than Chandra's available observing time. To achieve fully scheduled weeks, and to increase Chandra's efficiency we must allow the short-term scheduler some flexibility in target choice. This is done by reserving a pool of unconstrained targets with broad viewing windows, These targets are listed at the end of the long-term schedule, and may be scheduled at any time during the cycle to fill undersubscribed weeks.
The long-term schedule page has links to our database entries of the requested observing parameters as well as to images of the target fields of view. Observers are encouraged to review these entries and notify the Chandra Director's Office of any perceived problems. Observers may be contacted about a month prior to the detailed scheduling of their targets for final confirmation of the observing parameters. Note that the images accompanying the target pages assume a roll angle appropriate for the middle of the week to which the target has been assigned in the long-term schedule. This approximation, made for initial review purposes only, may not always respect accepted roll constraints. This will be corrected in the final scheduling process, which may also result in different guide stars than those shown in the optical image. Also, those targets allocated to the pool may be moved multiple times; the roll angles for their images are thus unlikely to correspond to the final orientation. Updates will be issued at the time of rescheduling.
If simultaneous observations with other instruments are a vital part of your program and if they were part of your peer-reviewed proposal, a time-constraint should be already applied to your target. Barring malfunctions, it will be honored. After a proposal has been reviewed and accepted, the addition of constraints, or changes in object, position or exposure time will not be honored. If you have added coordinated observations later or if only a secondary part of the science, we cannot perturb the normal scheduling to give you a definite time.
NOTE: In the text of the long-term schedule, pool targets are marked with a "P", Cool Catalog Targets (CCTs) are marked with "C", and roll and pitch angles given are for the start and end of each observation's assigned one-week interval.
Click here for a list of changes from the last LTS.
Click here for table header definitions.
Segment: 33 limit: 4.68d, used 4.38d = 93.59% 29-Sep-2025 00h to 06-Oct-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 291763 29531 Vega 2.0 279.237 38.786 269.2 275.3 94.6 91.4 HRC-I - - NONE Kashyap CAL 26 0 Y N N Y N N N N rpete 10/04/24 26200474 291764 29532 Vega 2.0 279.237 38.786 269.2 275.3 94.6 91.4 HRC-S - - NONE Kashyap CAL 26 0 Y N N Y N N N N rpete 10/04/24 26200474 291765 29533 Vega 1.0 279.237 38.786 269.2 275.3 94.6 91.4 HRC-S - - NONE Kashyap CAL 26 0 Y N N Y N N N N rpete 10/04/24 26200474 402491 28037 SMC 2857 19.5 14.417 -71.988 9.6 3.0 105.5 103.0 ACIS-S 4 2 NONE Ludwig GO 25 2 N N N N N N N N swolk 10/30/23 25400397 402528 29746 AT2025ulz 15.0 237.976 30.902 293.4 300.6 60.1 57.0 ACIS-S 4 2 NONE O'Connor TOO 26 0 S N N N N N N N waaron 08/22/25 26400095 402528 31902 AT2025ulz 17.0 237.976 30.902 293.4 300.6 60.1 57.0 ACIS-S 4 2 NONE O'Connor TOO 26 0 S N N N N N N N approval not required 26400095 402528 31903 AT2025ulz 18.0 237.976 30.902 293.4 300.6 60.1 57.0 ACIS-S 4 2 NONE O'Connor TOO 26 0 S N N N N N N N approval not required 26400095 503518 30116 SNR 1987A 30.0 83.867 -69.270 78.6 71.7 91.8 91.5 ACIS-S 6 2 HETG Park GO 26 0 Y Y N N N N N N nss 07/24/25 26500018 590775 29599 Cas A 2.0 350.858 58.815 197.0 205.0 122.4 123.9 ACIS-I 2 0 NONE Bogdan CAL 26 0 G N N N N N N Y abogdan 10/23/24 26500467 590776 29600 Cas A 2.0 350.858 58.815 197.0 205.0 122.4 123.9 ACIS-I 2 0 NONE Bogdan CAL 26 0 G N N N N N N Y abogdan 10/23/24 26500467 590777 29601 Cas A 2.0 350.858 58.815 197.0 205.0 122.4 123.9 ACIS-I 2 0 NONE Bogdan CAL 26 0 G N N N N N N Y abogdan 10/23/24 26500467 590778 29602 Cas A 2.0 350.858 58.815 197.0 205.0 122.4 123.9 ACIS-S 2 0 NONE Bogdan CAL 26 0 G N N N N N N Y abogdan 10/23/24 26500467 590779 29603 Cas A 2.0 350.858 58.815 197.0 205.0 122.4 123.9 ACIS-S 2 0 NONE Bogdan CAL 26 0 G N N N N N N Y abogdan 10/23/24 26500467 601591 28097 UM 351 12.0 24.594 1.901 88.6 76.3 160.6 166.6 ACIS-S 5 3 NONE Irwin GO 25 1 N N N N N N N N jeanconn 12/18/23 25620199 601591 31900 UM 351 13.0 24.594 1.901 88.6 76.3 160.6 166.6 ACIS-S 5 3 NONE Irwin GO 25 0 N N N N N N N N approval not required 25620199 601669 29859 WLM 10.0 0.492 -15.461 345.0 331.1 161.7 156.8 ACIS-I 6 2 NONE Lazzarini GO 26 0 N N N N N N N N waaron 11/21/24 26620010 601669 31904 WLM 12.0 0.492 -15.461 345.0 331.1 161.7 156.8 ACIS-I 6 2 NONE Lazzarini GO 26 0 N N N N N N N N approval not required 26620010 601669 31905 WLM 13.0 0.492 -15.461 345.0 331.1 161.7 156.8 ACIS-I 6 2 NONE Lazzarini GO 26 0 N N N N N N N N approval not required 26620010 601669 31906 WLM 12.0 0.492 -15.461 345.0 331.1 161.7 156.8 ACIS-I 6 2 NONE Lazzarini GO 26 0 N N N N N N N N approval not required 26620010 601669 31910 WLM 10.0 0.492 -15.461 345.0 331.1 161.7 156.8 ACIS-I 6 2 NONE Lazzarini GO 26 0 N N N N N N N N approval not required 26620010 601714 30851 II Zw 40 13.0 88.928 3.392 88.1 85.6 96.4 102.8 ACIS-I 4 0 NONE Oskinova GO 26 0 N N N N N N P N waaron 03/17/25 27620014 601714 31907 II Zw 40 35.0 88.928 3.392 88.1 85.6 96.4 102.8 ACIS-I 4 0 NONE Oskinova GO 26 0 N N N N N N P N approval not required 27620014 601714 31908 II Zw 40 28.0 88.928 3.392 88.1 85.6 96.4 102.8 ACIS-I 4 0 NONE Oskinova GO 26 0 N N N N N N P N approval not required 27620014 601714 31909 II Zw 40 24.0 88.928 3.392 88.1 85.6 96.4 102.8 ACIS-I 4 0 NONE Oskinova GO 26 0 N N N N N N P N approval not required 27620014 705496 C 31898 SDSSJ011132.32+13351 15.0 17.885 13.589 130.9 143.2 163.1 169.4 ACIS-S 2 0 NONE Civano CCT 26 0 N N N N N N N N CCT - approved 20701058 705497 C 31899 S82X-1094 15.0 16.940 1.260 84.9 55.2 168.2 173.4 ACIS-I 4 0 NONE Cappelluti CCT 26 0 N N N N N N N N CCT - approved 20701050 802116 28670 NGC410 13.0 17.745 33.152 156.5 167.0 147.0 151.3 ACIS-S 4 1 NONE O'Sullivan GO 25 0 N N N N N N N N bradw 10/16/23 25800020 802116 31901 NGC410 15.0 17.745 33.152 156.5 167.0 147.0 151.3 ACIS-S 4 1 NONE O'Sullivan GO 25 0 N N N N N N N N approval not required 25800020 901864 28136 IGR J17598-2236 5.0 269.950 -22.600 270.1 270.2 84.3 77.4 ACIS-S 2 0 NONE Chakraborty GO 25 0 N N N N N N N N dj 10/27/23 25910434 901886 30542 CMZ Molecular Cloud 20.0 266.550 -28.889 267.8 267.1 81.3 74.5 ACIS-I 4 0 NONE Vikhlinin GTO 26 0 N N N N N N N N dj 08/25/25 26910495 Segment: 34 limit: 4.68d, used 4.03d = 86.11% 06-Oct-2025 00h to 13-Oct-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503454 28051 PSR J2229+6114 40.0 337.272 61.236 219.5 227.4 118.2 118.6 ACIS-I 4 0 NONE Halpern GO 25 0 N N N N N N N N jeanconn 11/27/23 25500048 503557 29842 PSR J2017+3625 30.0 304.483 36.419 260.1 266.4 111.4 107.8 ACIS-I 4 0 NONE Romani GO 26 0 N N N N N N N N jeanconn 10/17/24 26500294 503584 30493 1E 161348-5055.1 30.0 244.401 -51.040 242.5 238.1 63.5 57.8 ACIS-S 2 0 NONE Garmire GTO 26 0 S N N Y N Y N Y jeanconn 11/07/24 26500496 601635 29640 NGC1546 55.0 63.652 -56.061 54.7 47.5 105.6 106.0 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601640 30153 NGC2566 30.0 124.690 -25.499 95.6 90.2 67.0 71.7 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 704981 H 28605 Abell 370 30.0 39.960 -1.586 76.8 66.9 150.8 156.2 ACIS-I 4 0 NONE Bogdan GO 25 0 N N N N N N N N abogdan 09/13/23 25700214 704981 H 28626 Abell 370 30.0 39.960 -1.586 76.8 66.9 150.8 156.2 ACIS-I 4 0 NONE Bogdan GO 25 0 N N N N N N N N abogdan 09/13/23 25700214 705255 P 29967 SDSS J015634.87-0110 19.9 29.144 -1.184 70.5 51.4 161.3 165.8 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N malgosia 11/19/24 26700222 705276 29988 NGC 3516 36.0 166.698 72.569 25.2 31.3 79.2 82.7 ACIS-S 2 0 HETG Miller GO 26 0 N N N N N N N N hermanm 04/30/25 26700317 802135 28320 PSZ2G302.85-88.63 6.0 12.862 -28.498 2.4 351.4 146.5 143.5 ACIS-I 5 1 NONE McDonald GO 25 0 N N N N N N N N bradw 09/08/23 25800174 802153 28723 ACT-CL_J0034.4+0225 34.5 8.608 2.426 311.6 299.5 176.1 169.3 ACIS-S 5 1 NONE Hughes GO 25 0 N N N N N N N N bradw 11/02/23 25800453 901878 29904 IGR J07141+0146 5.0 108.547 1.744 84.8 82.3 83.2 89.7 ACIS-I 4 0 NONE Chakraborty GO 26 1 N N N N N N N N dj 12/03/24 26910413 Segment: 35 limit: 5.18d, used 4.46d = 86.10% 13-Oct-2025 00h to 20-Oct-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 201810 30088 TV Cassiopeia 30.0 4.828 59.139 196.5 205.1 127.5 128.9 ACIS-S 6 2 HETG Yang GO 26 0 N N N N N N N N nss 02/21/25 26200417 201814 30515 WR 11 20.0 122.383 -47.337 95.4 88.8 74.6 77.2 ACIS-S 6 2 HETG Gunderson GTO 26 0 S N Y N N Y P N nss 01/05/25 26200484 201815 30516 WR 11 20.0 122.383 -47.337 95.4 88.8 74.6 77.2 ACIS-S 6 2 HETG Gunderson GTO 26 0 S N Y N N Y P N nss 01/05/25 26200484 201816 30517 WR 11 20.0 122.383 -47.337 95.4 88.8 74.6 77.2 ACIS-S 6 2 HETG Gunderson GTO 26 0 S N Y N N Y P N nss 01/05/25 26200484 291766 29534 Vega 1.0 279.237 38.786 281.4 287.5 88.0 84.8 HRC-S - - NONE Kashyap CAL 26 0 Y N N Y N N N N rpete 10/04/24 26200474 291767 29535 Vega 1.0 279.237 38.786 281.4 287.5 88.0 84.8 HRC-S - - NONE Kashyap CAL 26 0 Y N N Y N N N N rpete 10/04/24 26200474 402588 30533 Cygnus X-2 30.0 326.172 38.321 250.5 257.8 124.3 121.0 ACIS-S 2 0 HETG Psaradaki GTO 26 0 N N N N N N N N approval not required 26400494 503551 30729 PSR J1418-6058 16.0 214.678 -60.968 200.4 192.9 54.8 51.3 ACIS-I 4 0 NONE Romani GO 26 2 N N N N N N N N jeanconn 03/14/25 26500294 503559 29844 PSR J1957+5033 29.0 299.410 50.556 266.0 272.8 103.1 101.0 ACIS-I 4 0 NONE Romani GO 26 0 N N N N N N N N jeanconn 10/17/24 26500308 601666 30184 IC5273 30.0 344.861 -37.703 318.5 313.9 125.1 119.4 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601667 29672 NGC7456 22.0 345.543 -39.569 320.1 315.3 124.1 118.5 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601686 29876 Mrk 247 18.0 198.652 54.798 359.2 6.3 62.4 65.2 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 705254 29966 SDSS J014137.22-0914 23.8 25.404 -9.244 23.9 2.8 161.6 160.5 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N malgosia 11/19/24 26700222 705257 29969 SDSS J005855.46+0100 23.4 14.731 1.005 334.1 313.9 172.6 166.6 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N malgosia 11/19/24 26700222 705305 30235 [vD2023]1 30.0 40.440 -8.351 55.1 40.9 152.5 155.6 ACIS-I 4 0 NONE Tremblay GO 26 0 N N N N N N N N bradw 11/07/24 26700422 705306 30018 PS16dtm 20.0 29.520 -0.873 53.3 24.3 165.7 167.8 ACIS-S 2 0 NONE Blanchard GO 26 0 Y N N N N N N N bradw 10/10/24 26700454 802205 30410 MACS J0018.5+1626 30.0 4.639 16.443 237.5 254.6 164.3 159.7 ACIS-I 4 0 NONE Sayers GO 26 0 N N N N N N N N bradw 11/12/24 26800149 802210 30028 SPT-CLJ0421-4845 20.0 65.321 -48.761 50.9 43.6 110.0 110.9 ACIS-I 4 0 NONE Floyd GO 26 0 N N N N N N N Y bradw 11/10/24 26800279 Segment: 36 limit: 4.68d, used 4.09d = 87.39% 20-Oct-2025 00h to 27-Oct-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 201810 30086 TV Cassiopeia 30.0 4.828 59.139 205.1 214.1 128.9 129.6 ACIS-S 6 2 HETG Yang GO 26 0 N N N N N N N N nss 02/21/25 26200417 201817 30518 WR 11 20.0 122.383 -47.337 88.8 82.2 77.2 79.9 ACIS-S 6 2 HETG Gunderson GTO 26 0 S N Y N N Y P N nss 01/05/25 26200484 201818 30519 WR 11 20.0 122.383 -47.337 88.8 82.2 77.2 79.9 ACIS-S 6 2 HETG Gunderson GTO 26 0 S N Y N N Y P N nss 01/05/25 26200484 503554 31002 PSR J1813-1246 13.0 273.349 -12.767 275.9 277.5 67.4 60.5 ACIS-I 4 0 NONE Romani GO 26 0 N N N N N N N N approval not required 26500294 601635 30147 NGC1546 30.0 63.652 -56.061 40.4 33.1 106.2 106.1 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601643 29648 NGC3137 49.0 152.281 -29.064 100.1 93.6 52.2 56.8 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601672 29862 AM0126-525 40.0 22.105 -52.636 357.4 350.3 117.1 114.2 ACIS-S 4 2 NONE Fruscione GO 26 0 N N N N N N N N waaron 12/07/24 26620058 705305 30233 [vD2023]1 30.0 40.440 -8.351 40.9 23.8 155.6 157.0 ACIS-I 4 0 NONE Tremblay GO 26 0 N N N N N N N N bradw 11/07/24 26700422 705305 30236 [vD2023]1 30.0 40.440 -8.351 40.9 23.8 155.6 157.0 ACIS-I 4 0 NONE Tremblay GO 26 0 N N N N N N N N bradw 11/07/24 26700422 802205 30411 MACS J0018.5+1626 30.0 4.639 16.443 254.6 265.2 159.7 154.1 ACIS-I 4 0 NONE Sayers GO 26 0 N N N N N N N N bradw 11/12/24 26800149 802237 30538 1RXS J021649.0+70355 30.0 34.204 70.598 169.0 176.5 119.3 122.1 ACIS-I 4 0 NONE Tumer GTO 26 0 N N N N N N N N bradw 11/18/24 26800482 802237 30539 1RXS J021649.0+70355 30.0 34.204 70.598 169.0 176.5 119.3 122.1 ACIS-I 4 0 NONE Tumer GTO 26 0 N N N N N N N N bradw 11/18/24 26800482 Segment: 37 limit: 4.84d, used 4.19d = 86.57% 27-Oct-2025 00h to 03-Nov-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402575 29793 IC 10 X-1 30.0 5.121 59.281 213.7 222.8 129.5 129.5 ACIS-S 6 4 NONE Laycock GO 26 0 N N Y N N N N N not approved 26400357 402597 30505 Vela X-1 15.0 135.529 -40.555 89.4 83.2 70.9 74.7 ACIS-S 5 2 HETG Huenemoerder GTO 26 0 N N Y N N N N N hermanm 12/02/24 26400492 503531 30122 Cassiopeia A 30.0 350.871 58.820 230.3 238.8 125.0 124.1 ACIS-S 2 0 NONE Yamada GO 26 0 N N N N N N N N jeanconn 11/15/24 26500140 503560 29845 PSR J2055+2539 30.0 313.954 25.666 276.3 281.1 106.9 101.7 ACIS-I 4 0 NONE Romani GO 26 0 N N N N N N N N jeanconn 10/17/24 26500308 601634 30146 IC1954 30.0 52.881 -51.905 23.1 15.5 112.7 111.9 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601639 29644 NGC2283 28.0 101.471 -18.212 71.3 66.3 104.1 109.2 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601646 29651 NGC3596 36.0 168.776 14.787 58.9 60.7 50.1 57.0 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601683 29873 SDSS J023749.52-0925 23.0 39.456 -9.432 20.6 3.4 156.4 155.6 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 705264 29976 SDSS J130557.09+3250 22.7 196.489 32.837 19.5 26.7 47.6 52.0 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N malgosia 11/19/24 26700222 705305 30229 [vD2023]1 30.0 40.440 -8.351 23.8 6.0 157.0 156.6 ACIS-I 4 0 NONE Tremblay GO 26 0 N N N N N N N N bradw 11/07/24 26700422 705305 30230 [vD2023]1 30.0 40.440 -8.351 23.8 6.0 157.0 156.6 ACIS-I 4 0 NONE Tremblay GO 26 0 N N N N N N N N bradw 11/07/24 26700422 802200 30370 Perseus cluster E 30.0 50.060 41.509 144.7 155.0 146.8 151.4 ACIS-I 5 1 NONE Fabian CLP 25 0 N N N N N N N Y bradw 11/14/24 25808977 802201 30378 Abell 795 26.3 141.022 14.173 72.2 72.1 74.5 81.5 ACIS-S 4 2 NONE UBERTOSI GO 26 0 N N N N N N N N bradw 10/29/24 26800045 Segment: 38 limit: 5.10d, used 4.08d = 80.00% 03-Nov-2025 00h to 10-Nov-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 291762 29530 HZ43 2.0 199.090 29.098 25.0 31.7 47.7 52.5 HRC-I - - LETG Kashyap CAL 26 0 Y N N Y N N N N kashyap 04/14/25 26200472 291769 29537 HZ43 20.0 199.090 29.098 25.0 31.7 47.7 52.5 HRC-S - - LETG Kashyap CAL 26 0 Y N N N N N N N kashyap 04/14/25 26200475 300558 30099 VV Pup 30.0 123.778 -19.055 74.5 70.2 89.0 94.5 ACIS-S 6 2 HETG Rodriguez GO 26 0 N N N N N N N N nss 03/26/25 26300401 503540 29825 SN 1986J 15.0 35.631 42.332 184.9 200.2 152.5 153.5 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236 601631 30141 NGC0685 28.2 26.928 -52.762 348.5 341.9 111.6 108.5 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601644 29649 NGC3239 23.0 156.270 17.164 65.9 66.7 68.8 75.7 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601645 29650 NGC3511 34.0 165.849 -23.087 89.7 84.6 49.7 55.4 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601666 29671 IC5273 47.0 344.861 -37.703 305.9 302.3 107.5 101.4 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601684 29874 SDSS J131603.91+2922 23.0 199.016 29.382 25.0 31.6 48.0 52.7 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 705214 29926 SDSS J022226.11-0857 24.8 35.609 -8.950 354.4 340.5 156.0 152.4 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N kashyap 03/11/25 26700090 802196 30315 Perseus cluster 30.0 49.951 41.512 155.2 168.5 151.5 155.2 ACIS-I 5 1 NONE Fabian CLP 25 0 N N N N N N N Y bradw 11/14/24 25808977 802211 30029 SPT-CLJ0446-4606 25.0 71.732 -46.101 35.3 27.8 111.8 112.3 ACIS-I 4 0 NONE Floyd GO 26 0 N N N N N N N Y bradw 11/10/24 26800279 802230 30488 PSZ2G144.99-24.64 50.0 37.189 34.027 182.3 204.1 160.9 161.7 ACIS-I 4 0 NONE Rajpurohit GTO 26 0 N N N N N N N N bradw 11/01/24 26800498 Segment: 39 limit: 4.77d, used 4.14d = 86.79% 10-Nov-2025 00h to 17-Nov-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 601634 29639 IC1954 52.0 52.881 -51.905 8.2 0.8 110.7 109.2 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601647 30161 NGC3626 30.0 170.016 18.357 60.0 61.8 64.6 71.4 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601647 30162 NGC3626 30.0 170.016 18.357 60.0 61.8 64.6 71.4 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601706 30496 NGC 1140 34.0 43.640 -10.029 357.3 344.0 152.9 149.9 ACIS-S 2 0 NONE Monson GTO 26 0 N N N N N N N N waaron 11/18/24 26620493 705017 31488 NGC 4579 19.0 189.432 11.818 51.2 54.3 45.4 52.1 ACIS-S 6 2 HETG Shi GO 25 0 N N N N N N N N approval not required 25700279 705224 29936 NGC 1358 30.0 53.415 -5.090 20.6 3.1 156.3 155.9 ACIS-S 5 1 NONE Marchesi GO 26 0 S N N N N Y Y N kashyap 03/31/25 26700102 705273 29985 MCG-5-23-16 32.0 146.917 -30.949 80.9 75.9 71.2 76.4 ACIS-S 1 0 HETG Miller GO 26 0 N N N N N N N N hermanm 04/30/25 26700317 705279 30224 NGC 4051 20.0 180.790 44.531 43.9 48.8 73.5 78.8 ACIS-S 2 0 HETG Miller GO 26 0 N N N N N N N N hermanm 04/30/25 26700317 802196 29631 Perseus cluster 50.0 49.951 41.512 168.5 185.2 155.2 157.3 ACIS-I 5 1 NONE Fabian CLP 25 0 N N N N N N N Y bradw 11/14/24 25808977 802196 30301 Perseus cluster 30.0 49.951 41.512 168.5 185.2 155.2 157.3 ACIS-I 5 1 NONE Fabian CLP 25 0 N N N N N N N Y bradw 11/14/24 25808977 802201 30377 Abell 795 30.0 141.022 14.173 72.0 71.8 88.5 95.5 ACIS-S 4 2 NONE UBERTOSI GO 26 0 N N N N N N N N bradw 10/29/24 26800045 Segment: 40 limit: 5.01d, used 1.00d = 19.96% 17-Nov-2025 00h to 24-Nov-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503497 30105 PSR J1101-6101 30.0 165.438 -61.028 101.1 93.6 62.3 64.5 ACIS-I 4 0 NONE Kargaltsev GO 26 0 Y N N N N N N N approval not required 25500121 601705 29895 VV 114 17.0 16.947 -17.507 314.9 310.6 129.8 123.7 HRC-I - - NONE Kuczek GO 26 0 N N N N N N N N kashyap 07/06/25 26620288 705242 29954 WISE J121857.42+1035 27.1 184.739 10.598 57.9 59.9 55.2 62.1 ACIS-S 3 0 NONE Pfeifle GO 26 0 Y N N N N N N N malgosia 10/28/24 26700211 802216 30034 ACT-CL J2317.7-3648 12.0 349.433 -36.812 301.8 298.2 98.8 92.7 ACIS-S 3 0 NONE Flores GO 26 0 N N N N N N N N bradw 10/10/24 26800300 Segment: 41 limit: 5.02d, used 0.69d = 13.75% 24-Nov-2025 00h to 01-Dec-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402596 30504 Vela X-1 15.0 135.529 -40.555 65.7 59.9 86.7 90.9 ACIS-S 5 2 HETG Huenemoerder GTO 26 0 N N Y N N N N N hermanm 12/02/24 26400492 503579 30543 SN 2012au 15.0 193.717 -10.247 71.3 70.3 45.1 52.1 HRC-I - - NONE Patnaude GTO 26 0 N N N N N N N N kashyap 12/17/24 26500499 705225 29937 NGC 1358 30.0 53.415 -5.090 347.2 334.4 153.8 150.1 ACIS-S 5 1 NONE Marchesi GO 26 0 S N N N N Y Y N kashyap 03/31/25 26700102 Segment: 42 limit: 4.84d, used 1.60d = 33.06% 01-Dec-2025 00h to 08-Dec-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 201574 26967 XI BOO 5.0 222.848 19.100 31.0 37.9 47.1 52.0 HRC-I - - NONE Ayres GO 26 0 S N N N N Y N N kashyap 10/15/22 24200057 201820 30521 zeta Tau 50.0 84.411 21.143 84.6 78.5 163.7 170.7 ACIS-S 6 2 HETG Gunderson GTO 26 0 N N Y N N N N N nss 06/12/25 26200483 402584 30050 EXO 0748-676 30.0 117.140 -67.752 46.0 38.9 83.2 84.2 ACIS-S 3 1 NONE Homan TOO 26 0 S N N N N Y N N malgosia 05/01/25 26400303 503503 28359 GW170817 30.0 197.450 -23.381 81.9 78.7 45.4 52.1 ACIS-S 5 3 NONE Troja GO 26 1 Y N N N N N N N jeanconn 11/27/23 25510368 705244 29956 SDSS J101756.75+3448 22.3 154.487 34.814 73.1 76.1 104.1 110.6 ACIS-S 2 0 NONE Pfeifle GO 26 0 N N N N N N N N malgosia 10/28/24 26700211 Segment: 43 limit: 5.20d, used 0.47d = 9.04% 08-Dec-2025 00h to 15-Dec-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503503 30111 GW170817 30.0 197.450 -23.381 78.7 76.0 52.1 58.9 ACIS-S 5 3 NONE Troja GO 26 0 Y N N N N N N N approval not required 25510368 705283 29995 ASASSN-14ko 10.0 81.326 -46.006 6.8 359.2 111.0 110.7 ACIS-S 4 0 NONE Auchettl GO 26 0 Y N N N N Y N N malgosia 04/07/25 26700325 Segment: 44 limit: 4.90d, used 0.52d = 10.61% 15-Dec-2025 00h to 22-Dec-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402591 30499 Vela X-1 15.0 135.529 -40.555 48.3 42.3 99.2 103.2 ACIS-S 5 2 HETG Huenemoerder GTO 26 0 N N Y N N N N N hermanm 12/02/24 26400492 503503 30115 GW170817 30.0 197.450 -23.381 76.0 73.7 58.9 65.7 ACIS-S 5 3 NONE Troja GO 26 0 Y N N N N N N N approval not required 25510368 Segment: 45 limit: 4.86d, used 1.19d = 24.49% 22-Dec-2025 00h to 29-Dec-2025 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402598 30506 Vela X-1 15.0 135.529 -40.555 42.3 36.1 103.2 107.1 ACIS-S 5 2 HETG Huenemoerder GTO 26 0 N N Y N N N N N hermanm 12/02/24 26400492 503541 29826 SN 1986J 15.0 35.631 42.332 265.0 270.2 131.6 125.7 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236 601652 29657 NGC4536 34.0 188.613 2.188 66.0 66.7 82.9 90.0 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 705284 29996 ASASSN-14ko 40.0 81.326 -46.006 351.6 344.1 110.1 109.1 ACIS-S 4 0 NONE Auchettl GO 26 0 S N N N N Y N N malgosia 04/07/25 26700325 Segment: 46 limit: 5.28d, used 1.63d = 30.87% 29-Dec-2025 00h to 05-Jan-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 601652 30169 NGC4536 30.0 188.613 2.188 66.7 67.4 90.0 97.1 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 705226 29938 NGC 1358 30.0 53.415 -5.090 305.2 300.9 128.3 122.1 ACIS-S 5 1 NONE Marchesi GO 26 0 S N N N N Y Y N kashyap 03/31/25 26700102 705287 29999 2MASX J01110461-4558 50.0 17.769 -45.979 293.3 287.8 80.0 75.4 ACIS-S 4 0 NONE Lin GO 26 0 S N N N N Y N N malgosia 03/31/25 26700329 705287 30226 2MASX J01110461-4558 30.0 17.769 -45.979 293.3 287.8 80.0 75.4 ACIS-S 4 0 NONE Lin GO 26 0 S N N N N Y N N malgosia 03/31/25 26700329 Segment: 47 limit: 4.89d, used 0.70d = 14.31% 05-Jan-2026 00h to 12-Jan-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503548 29833 SN2025sei 50.0 267.248 25.496 21.6 30.2 51.3 53.5 ACIS-S 2 0 NONE Chornock TOO 26 0 S N N N N Y N N malgosia 08/12/25 26500247 705285 29997 ASASSN-14ko 10.0 81.326 -46.006 336.7 329.4 107.9 106.3 ACIS-S 4 0 NONE Auchettl GO 26 0 S N N N N Y N N malgosia 04/07/25 26700325 Segment: 49 limit: 5.29d, used 0.35d = 6.62% 19-Jan-2026 00h to 26-Jan-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503497 30107 PSR J1101-6101 30.0 165.438 -61.028 41.3 35.3 90.9 94.6 ACIS-I 4 0 NONE Kargaltsev GO 26 0 Y N N N N N N N approval not required 25500121 Segment: 51 limit: 4.83d, used 0.16d = 3.31% 02-Feb-2026 00h to 09-Feb-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 705286 29998 ASASSN-14ko 14.0 81.326 -46.006 308.3 301.5 100.4 98.1 ACIS-S 4 0 NONE Auchettl GO 26 0 S N N N N Y N N malgosia 04/07/25 26700325 Segment: 52 limit: 5.25d, used 0.81d = 15.43% 09-Feb-2026 00h to 16-Feb-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402579 29797 Cir X-1 55.0 230.171 -57.167 80.1 75.7 78.6 84.2 ACIS-S 4 0 HETG Schulz GO 26 0 N N Y N N N N N nss 06/12/25 26400427 503542 29827 SN 1986J 15.0 35.631 42.332 292.1 295.3 88.2 81.9 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236 Segment: 58 limit: 5.14d, used 0.17d = 3.31% 23-Mar-2026 00h to 30-Mar-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503543 29828 SN 1986J 15.0 35.631 42.332 314.6 320.2 51.5 45.9 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236 Segment: 63 limit: 5.28d, used 0.64d = 12.12% 27-Apr-2026 00h to 04-May-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 201568 26961 WR 25 55.0 161.043 -59.720 296.5 288.8 119.9 118.7 ACIS-S 6 2 HETG Huenemoerder GO 26 0 N N Y N N N N N nss 10/17/22 24200045 Segment: 71 limit: 4.93d, used 0.17d = 3.45% 22-Jun-2026 00h to 29-Jun-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503544 29829 SN 1986J 15.0 35.631 42.332 85.0 90.0 48.6 54.1 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236 Segment: 79 limit: 4.72d, used 0.17d = 3.60% 17-Aug-2026 00h to 24-Aug-2026 00h (UT) seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 503545 29830 SN 1986J 15.0 35.631 42.332 113.8 116.9 95.3 101.3 ACIS-S 4 2 NONE Dwarkadas GO 26 0 S N N N N Y N N jeanconn 11/01/24 26500236seq# obs name time RA dec Roll Range Pitch Range SI R O grat observer Type AO OR# TC RC PC UC PU SC Mlt CRem Approved Proposal# ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 402541 P 29759 1eRASS J112950.4+354 2.2 172.460 35.784 0.0 0.0 0.0 0.0 ACIS-S 3 0 NONE Zhao GO 26 0 N N N N N N N N swolk 10/16/24 26400131 402542 P 29760 1eRASS J120806.9+291 1.9 182.029 29.286 0.0 0.0 0.0 0.0 ACIS-S 3 0 NONE Zhao GO 26 1 N N N N N N N N swolk 10/16/24 26400131 503552 P 29837 PSR J1459-6053 30.0 224.876 -60.889 0.0 0.0 0.0 0.0 ACIS-I 4 0 NONE Romani GO 26 0 N N N N N N N N jeanconn 10/17/24 26500294 601641 P 30156 NGC2775 30.0 137.584 7.038 0.0 0.0 0.0 0.0 ACIS-S 5 1 NONE Mathur CLP 25 0 N N N N N N N N bradw 11/18/24 25628968 601657 P 29662 NGC4689 32.0 191.940 13.763 0.0 0.0 0.0 0.0 ACIS-S 4 0 NONE Mathur CLP 25 0 N N N N N N N N bradw 12/22/24 25628968 601671 P 29861 AM0322-374 25.0 50.978 -37.510 0.0 0.0 0.0 0.0 ACIS-S 4 2 NONE Fruscione GO 26 0 N N N N N N N N waaron 12/07/24 26620058 601691 P 29881 SDSS J122558.56+0428 23.0 186.494 4.474 0.0 0.0 0.0 0.0 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 601692 P 29882 SDSS J125354.49+2624 27.0 193.477 26.410 0.0 0.0 0.0 0.0 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 601693 P 29883 SDSS J152322.13+1241 28.0 230.842 12.693 0.0 0.0 0.0 0.0 ACIS-S 4 2 NONE Lehmer GO 26 0 N N N N N N N N waaron 10/16/24 26620185 601698 P 29888 NGVS J124352.48+1125 20.0 190.968 11.426 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Dage GO 26 0 N N N N N N N N waaron 10/25/24 26620188 601699 P 29889 NGVS J122636.42+1255 20.0 186.652 12.920 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Dage GO 26 0 N N N N N N N N waaron 10/25/24 26620188 705200 P 29912 SDSS J162501.98+4309 30.0 246.258 43.159 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Li GO 26 0 N N N N N N N N kashyap 09/23/25 26700041 705220 P 29932 SDSS J155007.62+2728 18.8 237.533 27.471 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N kashyap 03/11/25 26700090 705221 P 29933 SDSS J134234.31+1913 6.0 205.643 19.227 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Foord GO 26 0 N N N N N N N N kashyap 03/11/25 26700090 705232 P 30212 8C 1435+638 23.4 219.191 63.611 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Ighina GO 26 0 N N N N N N N N malgosia 10/11/24 26700199 705247 P 29959 2MASS J09270013+1900 16.0 141.750 19.008 0.0 0.0 0.0 0.0 ACIS-S 3 0 NONE Pfeifle GO 26 0 N N N N N N N N malgosia 11/19/24 26700211 705250 P 29962 AKARI-IRC-V1 J175700 30.0 269.251 59.133 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Chen GO 26 0 N N N N N N N N malgosia 03/24/25 26700215 705270 P 29982 IIZW083 27.0 306.733 -2.278 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE CAGLAR GO 26 0 N N N N N N N N malgosia 03/24/25 26700302 705299 P 30011 GAMA2258819 18.0 30.874 -9.491 0.0 0.0 0.0 0.0 ACIS-S 2 0 NONE Reines GO 26 0 N N N N N N N N malgosia 02/10/25 26700402 Pool Targets
seq# obsid target SI grat observer old LTS bin new LTS bin ------------------------------------------------------------------------------------------------ 601672 29862 AM0126-525 ACIS-S NONE Fruscione 13-Oct-2025 --> 20-Oct-2025 402588 30533 Cygnus X-2 ACIS-S HETG Psaradaki 20-Oct-2025 --> 13-Oct-2025 705496 C 31898 SDSSJ011132.32+13351 ACIS-S NONE Civano (not in lts) --> 29-Sep-2025 705497 C 31899 S82X-1094 ACIS-I NONE Cappelluti (not in lts) --> 29-Sep-2025 601591 31900 UM 351 ACIS-S NONE Irwin (not in lts) --> 29-Sep-2025 802116 31901 NGC410 ACIS-S NONE O'Sullivan (not in lts) --> 29-Sep-2025 402528 31902 AT2025ulz ACIS-S NONE O'Connor (not in lts) --> 29-Sep-2025 402528 31903 AT2025ulz ACIS-S NONE O'Connor (not in lts) --> 29-Sep-2025 601669 31904 WLM ACIS-I NONE Lazzarini (not in lts) --> 29-Sep-2025 601669 31905 WLM ACIS-I NONE Lazzarini (not in lts) --> 29-Sep-2025 601669 31906 WLM ACIS-I NONE Lazzarini (not in lts) --> 29-Sep-2025 601714 31907 II Zw 40 ACIS-I NONE Oskinova (not in lts) --> 29-Sep-2025 601714 31908 II Zw 40 ACIS-I NONE Oskinova (not in lts) --> 29-Sep-2025 601714 31909 II Zw 40 ACIS-I NONE Oskinova (not in lts) --> 29-Sep-2025 601669 31910 WLM ACIS-I NONE Lazzarini (not in lts) --> 29-Sep-2025 LTS changes
| Column | Definition |
|---|---|
seq# | Sequence number |
obs | Observation ID |
name | Target name |
time | Approved time (ksec.) |
RA | Right ascension (deg., J2000) |
dec | Declination (deg., J2000) |
Roll range | Roll angles at start and end of two-week bin |
Pitch range | Pitch angles at start and end of two-week bin |
SI | Science Instrument |
R | Requested chip count (ACIS only) |
O | Optional chip count (ACIS only) |
grat | Grating |
observer | Observer |
Type | Observation type (GO, GTO, TOO, DDT, CAL) |
AO | Cycle (announcement of opportunity) number |
OR# | Number of times displaced from a previous short-term schedule |
TC | Time constraint |
RC | Roll constraint |
PC | Phase constraint |
UC | Uninterrupt constraint |
PU | Pointing update constraint |
SC | Split interval constraint |
Mlt | Multiple telescopes (coordination constraint) |
CRem | Constraint in remarks |
Approved | Flight approval status |
Proposal # | Proposal number |
Possible constraint flags are (Y)es, (P)reference, (N)o. Time constraints may have (S)eries flags for monitoring observations, (G)roup flags for grouped observations, or (R)esponse window flags for TOOs and DDTs.
Last modified: 09/24/25
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