2026A LDT Schedule

(Most column headers include added "mouse over" information.)
January 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Thu Jan-01 13.1 b b 98% 99% 18:24-00:28 00:28-06:32 0.0 / 6.1 0.0 / 6.1 0.5 0.5 tbd tbd BM OW
Fri Jan-02 14.1 b b 100% 100% 18:25-00:29 00:29-06:32 0.0 / 6.1 0.0 / 6.0 0.5 0.5 tbd tbd IN OW
Sat Jan-03 14.7 b b 99% 99% 18:26-00:29 00:29-06:32 0.0 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd IN BS
Sun Jan-04 13.7 b b 96% 95% 18:26-00:29 00:29-06:32 0.2 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd IN BS
Mon Jan-05 12.7 g b 90% 89% 18:27-00:29 00:29-06:33 1.4 / 6.0 0.0 / 6.1 0.5 0.5 tbd tbd CS BS
Tue Jan-06 11.7 g b 82% 81% 18:28-00:30 00:30-06:33 2.5 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd BM CS
Wed Jan-07 10.7 D b 73% 72% 18:29-00:31 00:31-06:33 3.5 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd BM CS
Thu Jan-08 9.7 D g 63% 62% 18:29-00:31 00:31-06:33 4.5 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd BM OW
Fri Jan-09 8.7 D g 53% 53% 18:30-00:31 00:31-06:33 5.5 / 6.0 0.0 / 6.0 0.5 0.5 tbd tbd IN OW
Sat Jan-10 7.7 D g 0% 43% 18:31-00:32 00:32-06:33 5.5 / 6.0 0.9 / 6.0 0.5 0.5 tbd tbd BS OW
Sun Jan-11 6.7 D D 0% 33% 18:32-00:33 00:33-06:33 5.5 / 6.0 1.9 / 6.0 0.5 0.5 tbd tbd IN BS
Mon Jan-12 5.7 D D 0% 24% 18:33-00:33 00:33-06:33 5.5 / 6.0 2.9 / 6.0 0.5 0.5 tbd tbd CS BS
Tue Jan-13 4.7 D D 0% 16% 18:34-00:32 00:32-06:32 5.5 / 6.0 3.9 / 6.0 0.5 0.5 tbd tbd BM CS
Wed Jan-14 3.7 D D 0% 10% 18:34-00:33 00:33-06:32 5.5 / 6.0 4.8 / 6.0 0.5 0.5 tbd tbd BM CS
Thu Jan-15 2.7 D D 0% 5% 18:35-00:34 00:34-06:32 5.5 / 6.0 5.5 / 6.0 0.5 0.5 tbd tbd BM OW
Fri Jan-16 1.7 D D 0% 0% 18:36-00:34 00:34-06:32 5.5 / 6.0 5.5 / 6.0 0.5 0.5 tbd tbd IN OW
Sat Jan-17 0.7 D D 0% 0% 18:37-00:34 00:34-06:32 5.5 / 6.0 5.5 / 6.0 0.5 0.5 tbd tbd IN OW
Sun Jan-18 0.3 D D 0% 0% 18:38-00:35 00:35-06:31 5.5 / 6.0 5.5 / 5.9 0.5 0.5 tbd tbd IN BS
Mon Jan-19 1.3 D D 0% 0% 18:39-00:35 00:35-06:31 5.4 / 5.9 5.5 / 5.9 0.5 0.5 tbd tbd CS BS
Tue Jan-20 2.3 D D 5% 0% 18:40-00:35 00:35-06:31 4.9 / 5.9 5.5 / 5.9 0.5 0.5 tbd tbd BM BS
Wed Jan-21 3.3 D D 11% 0% 18:41-00:36 00:36-06:31 3.9 / 5.9 5.4 / 5.9 0.5 0.5 tbd tbd BM CS
Thu Jan-22 4.3 D D 19% 0% 18:41-00:35 00:35-06:30 2.8 / 5.9 5.4 / 5.9 0.5 0.5 tbd tbd BM OW
Fri Jan-23 5.3 D D 28% 0% 18:42-00:36 00:36-06:30 1.7 / 5.9 5.4 / 5.9 0.5 0.5 tbd tbd IN OW
Sat Jan-24 6.3 g D 39% 0% 18:43-00:36 00:36-06:29 0.6 / 5.9 5.4 / 5.9 0.5 0.5 tbd tbd IN OW
Sun Jan-25 7.3 g D 50% 51% 18:44-00:36 00:36-06:29 0.0 / 5.9 4.9 / 5.9 0.5 0.5 tbd tbd IN BS
Mon Jan-26 8.3 g D 62% 63% 18:45-00:37 00:37-06:28 0.0 / 5.9 3.7 / 5.8 0.5 0.5 tbd tbd CS BS
Tue Jan-27 9.3 b g 73% 74% 18:46-00:36 00:36-06:28 0.0 / 5.8 2.5 / 5.9 0.5 0.5 tbd tbd CS BS
Wed Jan-28 10.3 b g 83% 84% 18:47-00:37 00:37-06:27 0.0 / 5.8 1.3 / 5.8 0.5 0.5 tbd tbd BM CS
Thu Jan-29 11.3 b b 91% 92% 18:48-00:37 00:37-06:27 0.0 / 5.8 0.2 / 5.8 0.5 0.5 tbd tbd BM OW
Fri Jan-30 12.3 b b 96% 97% 18:49-00:37 00:37-06:26 0.0 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd IN OW
Sat Jan-31 13.3 b b 99% 100% 18:50-00:38 00:38-06:26 0.0 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd IN OW

February 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Sun Feb-01 14.3 b b 100% 100% 18:50-00:37 00:37-06:25 0.0 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd IN BS
Mon Feb-02 14.1 b b 98% 97% 18:51-00:38 00:38-06:24 0.0 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd CS BS
Tue Feb-03 13.1 b b 94% 93% 18:52-00:37 00:37-06:23 0.8 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd BM CS
Wed Feb-04 12.1 g b 87% 86% 18:53-00:38 00:38-06:23 1.9 / 5.8 0.0 / 5.8 0.5 0.5 tbd tbd BM CS
Thu Feb-05 11.1 g b 79% 79% 18:54-00:38 00:38-06:22 2.9 / 5.7 0.0 / 5.7 0.5 0.5 tbd tbd BM OW
Fri Feb-06 10.1 D g 70% 70% 18:55-00:39 00:39-06:21 3.9 / 5.7 0.0 / 5.7 0.5 0.5 tbd tbd IN OW
Sat Feb-07 9.1 D g 61% 61% 18:56-00:38 00:38-06:20 4.8 / 5.7 0.0 / 5.7 0.5 0.5 tbd tbd IN BS
Sun Feb-08 8.1 D g 0% 51% 18:57-00:39 00:39-06:20 5.2 / 5.7 0.6 / 5.7 0.5 0.5 tbd tbd IN BS
Mon Feb-09 7.1 D g 0% 41% 18:58-00:38 00:38-06:19 5.2 / 5.7 1.6 / 5.7 0.5 0.5 tbd tbd CS BS
Tue Feb-10 6.1 D D 0% 32% 18:59-00:38 00:38-06:18 5.2 / 5.7 2.6 / 5.7 0.5 0.5 tbd tbd BM CS
Wed Feb-11 5.1 D D 0% 23% 18:59-00:38 00:38-06:17 5.2 / 5.7 3.5 / 5.7 0.5 0.5 tbd tbd BM CS
Thu Feb-12 4.1 D D 0% 15% 19:00-00:38 00:38-06:16 5.1 / 5.6 4.3 / 5.6 0.5 0.5 tbd tbd BM OW
Fri Feb-13 3.1 D D 0% 9% 19:01-00:38 00:38-06:15 5.1 / 5.6 5.1 / 5.6 0.5 0.5 tbd tbd IN OW
Sat Feb-14 2.1 D D 0% 0% 19:02-00:38 00:38-06:14 5.1 / 5.6 5.1 / 5.6 0.5 0.5 tbd tbd BS OW
Sun Feb-15 1.1 D D 0% 0% 19:03-00:38 00:38-06:13 5.1 / 5.6 5.1 / 5.6 0.5 0.5 tbd tbd IN BS
Mon Feb-16 0.1 D D 0% 0% 19:04-00:38 00:38-06:12 5.1 / 5.6 5.1 / 5.6 0.5 0.5 tbd tbd CS BS
Tue Feb-17 0.9 D D 0% 0% 19:05-00:37 00:37-06:11 5.0 / 5.5 5.1 / 5.6 0.5 0.5 tbd tbd BM CS
Wed Feb-18 1.9 D D 3% 0% 19:06-00:38 00:38-06:10 5.0 / 5.5 5.1 / 5.5 0.5 0.5 tbd tbd BM CS
Thu Feb-19 2.9 D D 8% 0% 19:06-00:37 00:37-06:09 3.9 / 5.5 5.1 / 5.5 0.5 0.5 tbd tbd BM OW
Fri Feb-20 3.9 D D 15% 0% 19:07-00:38 00:38-06:08 2.8 / 5.5 5.0 / 5.5 0.5 0.5 tbd tbd IN OW
Sat Feb-21 4.9 D D 24% 0% 19:08-00:37 00:37-06:07 1.6 / 5.5 5.0 / 5.5 0.5 0.5 tbd tbd IN OW
Sun Feb-22 5.9 g D 35% 0% 19:09-00:38 00:38-06:06 0.5 / 5.5 5.0 / 5.5 0.5 0.5 tbd tbd IN BS
Mon Feb-23 6.9 g D 47% 47% 19:10-00:37 00:37-06:05 0.0 / 5.5 4.2 / 5.5 0.5 0.5 tbd tbd CS BS
Tue Feb-24 7.9 g D 58% 59% 19:11-00:37 00:37-06:03 0.0 / 5.4 3.0 / 5.4 0.5 0.5 tbd tbd BM BS
Wed Feb-25 8.9 g g 69% 71% 19:12-00:37 00:37-06:02 0.0 / 5.4 2.0 / 5.4 0.5 0.5 tbd tbd BM CS
Thu Feb-26 9.9 b g 79% 81% 19:12-00:37 00:37-06:01 0.0 / 5.4 1.1 / 5.4 0.5 0.5 tbd tbd BM OW
Fri Feb-27 10.9 b b 88% 89% 19:13-00:37 00:37-06:00 0.0 / 5.4 0.3 / 5.4 0.5 0.5 tbd tbd IN OW
Sat Feb-28 11.9 b b 94% 95% 19:14-00:36 00:36-05:59 0.0 / 5.4 0.0 / 5.4 0.5 0.5 tbd tbd IN OW

March 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Sun Mar-01 12.9 b b 98% 99% 19:15-00:36 00:36-05:57 0.0 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd IN BS
Mon Mar-02 13.9 b b 100% 100% 19:16-00:36 00:36-05:56 0.0 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd CS BS
Tue Mar-03 14.8 b b 99% 99% 19:17-00:36 00:36-05:55 0.0 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd CS BS
Wed Mar-04 13.8 b b 97% 96% 19:18-00:35 00:35-05:54 0.2 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd BM CS
Thu Mar-05 12.8 g b 92% 91% 19:18-00:36 00:36-05:52 1.2 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd BM OW
Fri Mar-06 11.8 g b 85% 85% 19:19-00:35 00:35-05:51 2.2 / 5.3 0.0 / 5.3 0.5 0.5 tbd tbd IN OW
Sat Mar-07 10.8 D b 78% 77% 19:20-00:35 00:35-05:50 3.2 / 5.2 0.0 / 5.2 0.5 0.5 tbd tbd IN OW
Sun Mar-08 9.8 D g 69% 69% 19:21-00:34 00:34-05:48 4.2 / 5.2 0.0 / 5.2 0.5 0.5 tbd tbd IN BS
Mon Mar-09 8.8 D g 0% 59% 19:22-00:34 00:34-05:47 4.7 / 5.2 0.5 / 5.2 0.5 0.5 tbd tbd CS BS
Tue Mar-10 7.8 D g 0% 50% 19:23-00:34 00:34-05:46 4.7 / 5.2 1.4 / 5.2 0.5 0.5 tbd tbd BM CS
Wed Mar-11 6.8 D D 0% 40% 19:23-00:34 00:34-05:44 4.7 / 5.2 2.3 / 5.2 0.5 0.5 tbd tbd BM CS
Thu Mar-12 5.8 D D 0% 30% 19:24-00:34 00:34-05:43 4.7 / 5.2 3.0 / 5.2 0.5 0.5 tbd tbd BM OW
Fri Mar-13 4.8 D D 0% 22% 19:25-00:33 00:33-05:42 4.7 / 5.1 3.7 / 5.2 0.5 0.5 tbd tbd IN OW
Sat Mar-14 3.8 D D 0% 14% 19:26-00:33 00:33-05:40 4.6 / 5.1 4.3 / 5.1 0.5 0.5 tbd tbd IN BS
Sun Mar-15 2.8 D D 0% 7% 19:27-00:32 00:32-05:39 4.6 / 5.1 4.6 / 5.1 0.5 0.5 tbd tbd IN BS
Mon Mar-16 1.8 D D 0% 0% 19:28-00:33 00:33-05:37 4.6 / 5.1 4.6 / 5.1 0.5 0.5 tbd tbd CS BS
Tue Mar-17 0.8 D D 0% 0% 19:28-00:32 00:32-05:36 4.6 / 5.1 4.6 / 5.1 0.5 0.5 tbd tbd BM CS
Wed Mar-18 0.2 D D 0% 0% 19:29-00:32 00:32-05:35 4.5 / 5.0 4.6 / 5.0 0.5 0.5 tbd tbd BM CS
Thu Mar-19 1.2 D D 1% 0% 19:30-00:31 00:31-05:33 4.5 / 5.0 4.5 / 5.0 0.5 0.5 tbd tbd BM OW
Fri Mar-20 2.2 D D 5% 0% 19:31-00:31 00:31-05:32 3.8 / 5.0 4.5 / 5.0 0.5 0.5 tbd tbd IN OW
Sat Mar-21 3.2 D D 12% 0% 19:32-00:31 00:31-05:30 2.5 / 5.0 4.5 / 5.0 0.5 0.5 tbd tbd BS OW
Sun Mar-22 4.2 D D 22% 0% 19:33-00:31 00:31-05:29 1.3 / 5.0 4.5 / 5.0 0.5 0.5 tbd tbd IN BS
Mon Mar-23 5.2 g D 32% 0% 19:33-00:31 00:31-05:27 0.1 / 5.0 4.5 / 4.9 0.5 0.5 tbd tbd CS BS
Tue Mar-24 6.2 g D 44% 44% 19:34-00:30 00:30-05:26 0.0 / 4.9 3.5 / 4.9 0.5 0.5 tbd tbd BM CS
Wed Mar-25 7.2 g D 55% 56% 19:35-00:30 00:30-05:25 0.0 / 4.9 2.5 / 4.9 0.5 0.5 tbd tbd BM CS
Thu Mar-26 8.2 g g 66% 67% 19:36-00:29 00:29-05:23 0.0 / 4.9 1.7 / 4.9 0.5 0.5 tbd tbd BM OW
Fri Mar-27 9.2 b g 76% 78% 19:37-00:30 00:30-05:22 0.0 / 4.9 1.0 / 4.9 0.5 0.5 tbd tbd IN OW
Sat Mar-28 10.2 b g 85% 86% 19:38-00:29 00:29-05:20 0.0 / 4.8 0.4 / 4.8 0.5 0.5 tbd tbd IN OW
Sun Mar-29 11.2 b b 92% 93% 19:38-00:29 00:29-05:19 0.0 / 4.8 0.0 / 4.8 0.5 0.5 tbd tbd IN BS
Mon Mar-30 12.2 b b 97% 97% 19:39-00:28 00:28-05:17 0.0 / 4.8 0.0 / 4.8 0.5 0.5 tbd tbd CS BS
Tue Mar-31 13.2 b b 99% 100% 19:40-00:28 00:28-05:16 0.0 / 4.8 0.0 / 4.8 0.5 0.5 tbd tbd BM BS

April 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Wed Apr-01 14.2 b b 100% 100% 19:41-00:28 00:28-05:14 0.0 / 4.8 0.0 / 4.8 0.5 0.5 tbd tbd BM CS
Thu Apr-02 14.1 b b 99% 98% 19:42-00:27 00:27-05:13 0.0 / 4.8 0.0 / 4.8 0.5 0.5 tbd tbd BM OW
Fri Apr-03 13.1 b b 95% 95% 19:43-00:27 00:27-05:11 0.6 / 4.7 0.0 / 4.7 0.5 0.5 tbd tbd IN OW
Sat Apr-04 12.1 g b 90% 90% 19:44-00:27 00:27-05:10 1.6 / 4.7 0.0 / 4.7 0.5 0.5 tbd tbd IN OW
Sun Apr-05 11.1 g b 84% 83% 19:45-00:27 00:27-05:08 2.6 / 4.7 0.0 / 4.7 0.5 0.5 tbd tbd IN BS
Mon Apr-06 10.1 D b 76% 76% 19:45-00:26 00:26-05:07 3.5 / 4.7 0.0 / 4.7 0.5 0.5 tbd tbd CS BS
Tue Apr-07 9.1 D g 0% 67% 19:46-00:26 00:26-05:06 4.2 / 4.7 0.2 / 4.7 0.5 0.5 tbd tbd CS BS
Wed Apr-08 8.1 D g 0% 58% 19:47-00:25 00:25-05:04 4.1 / 4.6 1.1 / 4.7 0.5 0.5 tbd tbd BM CS
Thu Apr-09 7.1 D g 0% 48% 19:48-00:26 00:26-05:03 4.1 / 4.6 1.8 / 4.6 0.5 0.5 tbd tbd BM OW
Fri Apr-10 6.1 D D 0% 38% 19:49-00:25 00:25-05:01 4.1 / 4.6 2.4 / 4.6 0.5 0.5 tbd tbd IN OW
Sat Apr-11 5.1 D D 0% 28% 19:50-00:25 00:25-05:00 4.1 / 4.6 2.9 / 4.6 0.5 0.5 tbd tbd IN OW
Sun Apr-12 4.2 D D 0% 19% 19:51-00:24 00:24-04:58 4.0 / 4.5 3.4 / 4.6 0.5 0.5 tbd tbd IN BS
Mon Apr-13 3.1 D D 0% 11% 19:52-00:25 00:25-04:57 4.0 / 4.5 3.9 / 4.5 0.5 0.5 tbd tbd CS BS
Tue Apr-14 2.1 D D 0% 5% 19:53-00:24 00:24-04:56 4.0 / 4.5 4.0 / 4.5 0.5 0.5 tbd tbd BM CS
Wed Apr-15 1.1 D D 0% 0% 19:54-00:24 00:24-04:54 4.0 / 4.5 4.0 / 4.5 0.5 0.5 tbd tbd BM CS
Thu Apr-16 0.2 D D 0% 0% 19:55-00:23 00:23-04:53 3.9 / 4.5 4.0 / 4.5 0.5 0.5 tbd tbd BM OW
Fri Apr-17 0.8 D D 0% 0% 19:56-00:24 00:24-04:51 3.9 / 4.5 3.9 / 4.5 0.5 0.5 tbd tbd IN OW
Sat Apr-18 1.8 D D 4% 0% 19:56-00:23 00:23-04:50 3.5 / 4.5 3.9 / 4.5 0.5 0.5 tbd tbd IN BS
Sun Apr-19 2.8 D D 10% 0% 19:57-00:23 00:23-04:49 2.2 / 4.4 3.9 / 4.4 0.5 0.5 tbd tbd IN BS
Mon Apr-20 3.8 D D 19% 0% 19:58-00:23 00:23-04:47 1.1 / 4.4 3.9 / 4.4 0.5 0.5 tbd tbd CS BS
Tue Apr-21 4.8 g D 29% 0% 19:59-00:23 00:23-04:46 0.0 / 4.4 3.9 / 4.4 0.5 0.5 tbd tbd BM CS
Wed Apr-22 5.8 g D 40% 41% 20:00-00:22 00:22-04:45 0.0 / 4.4 3.0 / 4.4 0.5 0.5 tbd tbd BM CS
Thu Apr-23 6.8 g D 52% 52% 20:01-00:22 00:22-04:43 0.0 / 4.3 2.3 / 4.3 0.5 0.5 tbd tbd BM OW
Fri Apr-24 7.8 g g 63% 63% 20:02-00:22 00:22-04:42 0.0 / 4.3 1.7 / 4.3 0.5 0.5 tbd tbd IN OW
Sat Apr-25 8.8 b g 73% 74% 20:03-00:22 00:22-04:41 0.0 / 4.3 1.2 / 4.3 0.5 0.5 tbd tbd BS OW
Sun Apr-26 9.8 b g 81% 82% 20:04-00:21 00:21-04:39 0.0 / 4.3 0.7 / 4.3 0.5 0.5 tbd tbd IN BS
Mon Apr-27 10.8 b b 89% 90% 20:05-00:22 00:22-04:38 0.0 / 4.3 0.3 / 4.3 0.5 0.5 tbd tbd CS BS
Tue Apr-28 11.8 b b 94% 95% 20:06-00:21 00:21-04:37 0.0 / 4.2 0.0 / 4.3 0.5 0.5 tbd tbd BM CS
Wed Apr-29 12.8 b b 98% 98% 20:07-00:22 00:22-04:35 0.0 / 4.2 0.0 / 4.2 0.5 0.5 tbd tbd BM CS
Thu Apr-30 13.8 b b 100% 100% 20:08-00:21 00:21-04:34 0.0 / 4.2 0.0 / 4.2 0.5 0.5 tbd tbd BM OW

May 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Fri May-01 14.5 b b 100% 99% 20:09-00:21 00:21-04:33 0.0 / 4.2 0.0 / 4.2 0.5 0.5 tbd tbd IN OW
Sat May-02 13.5 b b 98% 97% 20:10-00:21 00:21-04:32 0.0 / 4.2 0.0 / 4.2 0.5 0.5 tbd tbd IN OW
Sun May-03 12.5 g b 94% 94% 20:11-00:21 00:21-04:31 0.9 / 4.2 0.0 / 4.2 0.5 0.5 tbd tbd IN BS
Mon May-04 11.5 g b 89% 88% 20:12-00:21 00:21-04:29 1.8 / 4.2 0.0 / 4.1 0.5 0.5 tbd tbd CS BS
Tue May-05 10.5 D b 82% 81% 20:13-00:20 00:20-04:28 2.6 / 4.1 0.0 / 4.1 0.5 0.5 tbd tbd BM BS
Wed May-06 9.5 D b 74% 74% 20:14-00:21 00:21-04:27 3.3 / 4.1 0.0 / 4.1 0.5 0.5 tbd tbd BM CS
Thu May-07 8.5 D g 0% 65% 20:15-00:20 00:20-04:26 3.5 / 4.1 0.4 / 4.1 0.5 0.5 tbd tbd BM OW
Fri May-08 7.5 D g 0% 55% 20:16-00:21 00:21-04:25 3.5 / 4.1 1.0 / 4.1 0.5 0.5 tbd tbd IN OW
Sat May-09 6.5 D g 0% 45% 20:17-00:20 00:20-04:24 3.5 / 4.0 1.5 / 4.1 0.5 0.5 tbd tbd IN OW
Sun May-10 5.5 D D 0% 34% 20:18-00:20 00:20-04:23 3.5 / 4.0 1.9 / 4.0 0.5 0.5 tbd tbd IN BS
Mon May-11 4.5 D D 0% 25% 20:19-00:21 00:21-04:22 3.4 / 4.0 2.4 / 4.0 0.5 0.5 tbd tbd CS BS
Tue May-12 3.5 D D 0% 16% 20:20-00:20 00:20-04:21 3.4 / 4.0 2.8 / 4.0 0.5 0.5 tbd tbd CS BS
Wed May-13 2.5 D D 0% 8% 20:21-00:21 00:21-04:20 3.4 / 4.0 3.3 / 4.0 0.5 0.5 tbd tbd BM CS
Thu May-14 1.5 D D 0% 3% 20:22-00:20 00:20-04:19 3.4 / 4.0 3.4 / 4.0 0.5 0.5 tbd tbd BM OW
Fri May-15 0.5 D D 0% 0% 20:23-00:20 00:20-04:18 3.4 / 4.0 3.4 / 4.0 0.5 0.5 tbd tbd IN OW
Sat May-16 0.5 D D 0% 0% 20:24-00:21 00:21-04:17 3.4 / 4.0 3.4 / 3.9 0.5 0.5 tbd tbd IN OW
Sun May-17 1.5 D D 3% 0% 20:25-00:20 00:20-04:16 3.3 / 3.9 3.3 / 3.9 0.5 0.5 tbd tbd IN BS
Mon May-18 2.5 D D 8% 0% 20:26-00:20 00:20-04:15 2.2 / 3.9 3.3 / 3.9 0.5 0.5 tbd tbd CS BS
Tue May-19 3.5 D D 16% 0% 20:26-00:21 00:21-04:15 1.3 / 3.9 3.3 / 3.9 0.5 0.5 tbd tbd BM CS
Wed May-20 4.5 D D 26% 0% 20:27-00:20 00:20-04:14 0.5 / 3.9 3.3 / 3.9 0.5 0.5 tbd tbd BM CS
Thu May-21 5.5 g D 37% 37% 20:28-00:21 00:21-04:13 0.0 / 3.9 3.1 / 3.9 0.5 0.5 tbd tbd BM OW
Fri May-22 6.5 g D 48% 48% 20:29-00:21 00:21-04:12 0.0 / 3.9 2.6 / 3.9 0.5 0.5 tbd tbd IN OW
Sat May-23 7.5 g D 58% 59% 20:30-00:21 00:21-04:12 0.0 / 3.9 2.1 / 3.9 0.5 0.5 tbd tbd IN BS
Sun May-24 8.5 g g 68% 69% 20:31-00:21 00:21-04:11 0.0 / 3.8 1.7 / 3.8 0.5 0.5 tbd tbd IN BS
Mon May-25 9.5 b g 77% 78% 20:32-00:22 00:22-04:10 0.0 / 3.8 1.2 / 3.8 0.5 0.5 tbd tbd CS BS
Tue May-26 10.5 b g 85% 86% 20:33-00:21 00:21-04:10 0.0 / 3.8 0.8 / 3.8 0.5 0.5 tbd tbd BM CS
Wed May-27 11.5 b g 91% 92% 20:33-00:21 00:21-04:09 0.0 / 3.8 0.3 / 3.8 0.5 0.5 tbd tbd BM CS
Thu May-28 12.5 b b 96% 96% 20:34-00:22 00:22-04:08 0.0 / 3.8 0.0 / 3.8 0.5 0.5 tbd tbd BM OW
Fri May-29 13.5 b b 99% 99% 20:35-00:22 00:22-04:08 0.0 / 3.8 0.0 / 3.8 0.5 0.5 tbd tbd IN OW
Sat May-30 14.5 b b 100% 100% 20:36-00:22 00:22-04:07 0.0 / 3.8 0.0 / 3.8 0.5 0.5 tbd tbd BS OW
Sun May-31 13.9 b b 99% 99% 20:37-00:21 00:21-04:07 0.0 / 3.7 0.0 / 3.8 0.5 0.5 tbd tbd IN BS

June 2026 - LDT
DoW Date Moon days Dark Code Max moon Illum Time Range (MST) No moon/ night hrs Frac night Prog ID Principal Remote Instrument Requested Filters/Gratings TO Intended LMI Filter Setup Intended DeVeny Grating
Mon Jun-01 12.9 b b 97% 96% 20:37-00:22 00:22-04:07 0.1 / 3.8 0.0 / 3.8 0.5 0.5 tbd tbd CS BS
Tue Jun-02 11.9 g b 92% 92% 20:38-00:23 00:23-04:06 0.8 / 3.8 0.0 / 3.7 0.5 0.5 tbd tbd BM CS
Wed Jun-03 10.9 g b 87% 86% 20:39-00:22 00:22-04:06 1.4 / 3.7 0.0 / 3.7 0.5 0.5 tbd tbd BM CS
Thu Jun-04 9.9 D b 79% 79% 20:40-00:22 00:22-04:05 2.0 / 3.7 0.0 / 3.7 0.5 0.5 tbd tbd BM OW
Fri Jun-05 8.9 D g 71% 70% 20:40-00:22 00:22-04:05 2.5 / 3.7 0.0 / 3.7 0.5 0.5 tbd tbd IN OW
Sat Jun-06 7.9 D g 61% 61% 20:41-00:23 00:23-04:05 3.0 / 3.7 0.0 / 3.7 0.5 0.5 tbd tbd IN OW
Sun Jun-07 6.9 D g 0% 51% 20:41-00:23 00:23-04:05 3.0 / 3.7 0.3 / 3.7 0.5 0.5 tbd tbd IN BS
Mon Jun-08 5.9 D g 0% 40% 20:42-00:24 00:24-04:04 3.0 / 3.7 0.8 / 3.7 0.5 0.5 tbd tbd CS BS
Tue Jun-09 4.9 D D 0% 29% 20:43-00:24 00:24-04:04 3.0 / 3.7 1.2 / 3.7 0.5 0.5 tbd tbd BM BS
Wed Jun-10 3.9 D D 0% 19% 20:43-00:24 00:24-04:04 3.0 / 3.7 1.7 / 3.7 0.5 0.5 tbd tbd BM CS
Thu Jun-11 2.9 D D 0% 11% 20:44-00:23 00:23-04:04 3.0 / 3.6 2.4 / 3.7 0.5 0.5 tbd tbd BM OW
Fri Jun-12 1.9 D D 0% 4% 20:44-00:24 00:24-04:04 3.0 / 3.7 3.0 / 3.7 0.5 0.5 tbd tbd IN OW
Sat Jun-13 0.9 D D 0% 0% 20:45-00:24 00:24-04:04 3.0 / 3.6 3.0 / 3.7 0.5 0.5 tbd tbd IN OW
Sun Jun-14 0.1 D D 0% 0% 20:45-00:24 00:24-04:04 3.0 / 3.6 3.0 / 3.7 0.5 0.5 tbd tbd IN BS
Mon Jun-15 1.1 D D 2% 0% 20:46-00:25 00:25-04:04 3.0 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd CS BS
Tue Jun-16 2.1 D D 6% 0% 20:46-00:25 00:25-04:04 2.7 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd CS BS
Wed Jun-17 3.1 D D 13% 0% 20:46-00:25 00:25-04:04 2.0 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd BM CS
Thu Jun-18 4.1 D D 22% 0% 20:47-00:26 00:26-04:04 1.4 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd BM OW
Fri Jun-19 5.1 D D 32% 0% 20:47-00:26 00:26-04:04 0.9 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd IN OW
Sat Jun-20 6.1 g D 43% 0% 20:47-00:26 00:26-04:05 0.5 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd IN OW
Sun Jun-21 7.1 g D 54% 0% 20:47-00:26 00:26-04:05 0.1 / 3.6 3.0 / 3.6 0.5 0.5 tbd tbd IN BS
Mon Jun-22 8.1 g D 64% 64% 20:47-00:27 00:27-04:05 0.0 / 3.7 2.6 / 3.6 0.5 0.5 tbd tbd CS BS
Tue Jun-23 9.1 b D 73% 73% 20:48-00:27 00:27-04:05 0.0 / 3.6 2.2 / 3.6 0.5 0.5 tbd tbd BM CS
Wed Jun-24 10.1 b g 81% 81% 20:48-00:27 00:27-04:06 0.0 / 3.6 1.7 / 3.6 0.5 0.5 tbd tbd BM CS
Thu Jun-25 11.1 b g 88% 88% 20:48-00:27 00:27-04:06 0.0 / 3.6 1.2 / 3.6 0.5 0.5 tbd tbd BM OW
Fri Jun-26 12.1 b g 93% 94% 20:48-00:27 00:27-04:06 0.0 / 3.6 0.5 / 3.6 0.5 0.5 tbd tbd IN OW
Sat Jun-27 13.1 b b 97% 97% 20:48-00:27 00:27-04:07 0.0 / 3.6 0.0 / 3.7 0.5 0.5 tbd tbd IN BS
Sun Jun-28 14.1 b b 99% 99% 20:48-00:27 00:27-04:07 0.0 / 3.6 0.0 / 3.7 0.5 0.5 tbd tbd IN BS
Mon Jun-29 14.1 b b 100% 100% 20:48-00:27 00:27-04:08 0.0 / 3.6 0.0 / 3.7 0.5 0.5 tbd tbd CS BS
Tue Jun-30 13.1 b b 99% 98% 20:48-00:28 00:28-04:08 0.0 / 3.7 0.0 / 3.7 0.5 0.5 tbd tbd BM CS

Note: Half-night handover times are calculated for local astronomical midnight.

Note: Nominal night duration is from Nautical Twilight (12deg) to Nautical Twilight.

Program ID codes: L=Lowell, B=BU, G=UT/KASI(IGRINS), M=UMd/GSFC, N=NAU, T=UToledo, W=Weizmann, X=External, Y=Yale, E=Engineering

Dark code (D=dark, g=gray, b=bright) methodology: At a time resolution of 1 minute, calculate the fractional illumination of the moon for the allocated time (ignoring time during astronomical/nautical/civil twilights & setting to zero for when the moon is below the horizon). Determine the dark code from the mean value of this metric where D=dark for <={0}, g=gray for <={1}, and b=bright for >0.7.

Remote: If entry is "Remote Requested", then remote observing request is pending and not yet approved. If entry is "Remote" then remote request is approved. If entry is blank, or is "On-Site", then observers are expected to be on-site at LDT.

Bolded red items are Time Critical Observations, during which ToO interrupts will not be accepted.

Italicized gray items are engineering optional interrupts (EOI) for brief testing. Principal will be notified before the start of the prior night if any of this time will be used for a quick engineering test.

2026A Approved Target of Opportunity (ToO) Programs
Program ID Principal ToO Type Time Allocated (hours) Time Remaining (hours) Requested Instrument & Filters/Grating
Totals 0.00 0.00

On nights when the DeVeny is not in use, it should be left in the following configuration in order to be ready for ToO programs:

	Grating: DV2 (300 lines / mm, 4000A blaze)
	Grating tilt: 22.28
	Collimator Focus: 11.25 mm
	Slit Width: 1.5" (0.23 mm)
	Rear Filter Wheel: Clear
	Front Filter Wheel: Clear

Targets of Opportunity (ToO) requests: 1) will only be accepted for approved ToO programs. 2) will not be accepted during any Time Critical Observation (TCO). 3) May be requested during engineering time (programs designated ENN), but will be accepted, delayed, or rejected at the discretion of the Principal or Lead Engineer for that engineering time. Click here to link to LDT policies regarding ToO programs.

Operations Staff (Position) email at lowell.edu:
    Timothy Ellsworth-Bowers (SuppAst) TB; tbowers@
    Jose Fernandez (LDTNtOpsMgr) JF; jfernandez@
    Robert Gallagher (Safety) RG; rgallagher@
    Hayden Green (Safety) HG; hgreen@
    Daniel Hiel (Safety) DH; dhiel@
    Kyler Kuehn (DirTech) KK; kkuehn@
    Vladimir Lee (Safety) VL; vlee@
    Stephen Levine (Ast/TelSci/DirEd) SL; sel@
    Beck Maier (TelOp) BM; emaier@
    Ishara Nisley (TelOp) IN; inisley@
    Observer (Observer) OBS;
    Ben Shafransky (TelOp) BS; bshafransky@
    Cecilia Siqueiros (TelOp) CS; csiqueiros@
    Visitor (Visitor) VST;
    Olivia Weiss (TelOp) OW; oweiss@

Summary of dates on which approved programs are scheduled (note some dates are partial nights):
tbd                    2026-01-01, 2026-01-02, 2026-01-03, 2026-01-04, 2026-01-05, 2026-01-06
                       2026-01-07, 2026-01-08, 2026-01-09, 2026-01-10, 2026-01-11, 2026-01-12
                       2026-01-13, 2026-01-14, 2026-01-15, 2026-01-16, 2026-01-17, 2026-01-18
                       2026-01-19, 2026-01-20, 2026-01-21, 2026-01-22, 2026-01-23, 2026-01-24
                       2026-01-25, 2026-01-26, 2026-01-27, 2026-01-28, 2026-01-29, 2026-01-30
                       2026-01-31, 2026-02-01, 2026-02-02, 2026-02-03, 2026-02-04, 2026-02-05
                       2026-02-06, 2026-02-07, 2026-02-08, 2026-02-09, 2026-02-10, 2026-02-11
                       2026-02-12, 2026-02-13, 2026-02-14, 2026-02-15, 2026-02-16, 2026-02-17
                       2026-02-18, 2026-02-19, 2026-02-20, 2026-02-21, 2026-02-22, 2026-02-23
                       2026-02-24, 2026-02-25, 2026-02-26, 2026-02-27, 2026-02-28, 2026-03-01
                       2026-03-02, 2026-03-03, 2026-03-04, 2026-03-05, 2026-03-06, 2026-03-07
                       2026-03-08, 2026-03-09, 2026-03-10, 2026-03-11, 2026-03-12, 2026-03-13
                       2026-03-14, 2026-03-15, 2026-03-16, 2026-03-17, 2026-03-18, 2026-03-19
                       2026-03-20, 2026-03-21, 2026-03-22, 2026-03-23, 2026-03-24, 2026-03-25
                       2026-03-26, 2026-03-27, 2026-03-28, 2026-03-29, 2026-03-30, 2026-03-31
                       2026-04-01, 2026-04-02, 2026-04-03, 2026-04-04, 2026-04-05, 2026-04-06
                       2026-04-07, 2026-04-08, 2026-04-09, 2026-04-10, 2026-04-11, 2026-04-12
                       2026-04-13, 2026-04-14, 2026-04-15, 2026-04-16, 2026-04-17, 2026-04-18
                       2026-04-19, 2026-04-20, 2026-04-21, 2026-04-22, 2026-04-23, 2026-04-24
                       2026-04-25, 2026-04-26, 2026-04-27, 2026-04-28, 2026-04-29, 2026-04-30
                       2026-05-01, 2026-05-02, 2026-05-03, 2026-05-04, 2026-05-05, 2026-05-06
                       2026-05-07, 2026-05-08, 2026-05-09, 2026-05-10, 2026-05-11, 2026-05-12
                       2026-05-13, 2026-05-14, 2026-05-15, 2026-05-16, 2026-05-17, 2026-05-18
                       2026-05-19, 2026-05-20, 2026-05-21, 2026-05-22, 2026-05-23, 2026-05-24
                       2026-05-25, 2026-05-26, 2026-05-27, 2026-05-28, 2026-05-29, 2026-05-30
                       2026-05-31, 2026-06-01, 2026-06-02, 2026-06-03, 2026-06-04, 2026-06-05
                       2026-06-06, 2026-06-07, 2026-06-08, 2026-06-09, 2026-06-10, 2026-06-11
                       2026-06-12, 2026-06-13, 2026-06-14, 2026-06-15, 2026-06-16, 2026-06-17
                       2026-06-18, 2026-06-19, 2026-06-20, 2026-06-21, 2026-06-22, 2026-06-23
                       2026-06-24, 2026-06-25, 2026-06-26, 2026-06-27, 2026-06-28, 2026-06-29
                       2026-06-30


ID  PI Name            Title
tbd

Latest as of 2025-10-30T18:49:27.526908 UTC