Bob Moler's Ephemeris Blog

This is Bob Moler with Ephemeris for Thursday, February 29th, the Leap Day or intercalary day. Today the Sun will be up for 11 hours and 8 minutes, setting at 6:30, and it will rise tomorrow at 7:19. The Moon, 3 days before last quarter, will rise at 11:59 this evening.

Let’s look at the skies for the month of March. The Sun will pass the celestial equator as the promising season of spring will begin. Daylight hours in the Interlochen/Traverse City area and will increase from 11 hours and 11 minutes Tomorrow to 12 hours 45 minutes on the 31st. The altitude, or angle, of the Sun above the southern horizon at local noon will be 38 degrees tomorrow and will ascend to nearly 50 degrees on the 31st. Spring will start on the 19th at 11:07 p.m. Part of the fault for that early date is the switch to daylight saving time this early in the year a while back. The Gregorian calendar reform of 1582 will keep the vernal equinox from falling much further back. So spring will come a bit early this year, calendar-wise.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

March Evening Star Chart

The planets and stars are plotted for the 15th at 10 p.m. EDT in the evening and 6 a.m. for the morning chart. These are the chart times. Note that Traverse City is located approximately 45 minutes behind our time meridian. (An hour and 45 minutes behind our Daylight Saving Time meridian during EDT). To duplicate the star positions on a planisphere (rotating star finder) you may have to set it to 45 minutes or 1 hour 45 minutes earlier than your current time.

Note the chart times of 10 p.m. and 6 a.m. are for the 15th. For each week before the 15th, add ½ hour (28 minutes if you’re picky). For each week after the 15th, subtract ½ hour. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog.

March Morning Star Chart

For a list of constellation names to go with the abbreviations click here.

• Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star.
• The leaky bowl of the Big Dipper drips on Leo.
• Follow the arc of the handle of the Big Dipper to the star Arcturus, and
• Extend it as a spike to Spica.
• The Summer Triangle appears in red.

Twilight Limits, Nautical and Astronomical

			EST
	Morning	Twilight	Evening	Twilight	Dark	Night	Moon
Date	Astro.	Nautical	Nautical	Astro.	Start	End	Illum.
2024-03-01	5h43m	6h17m	19h37m	20h11m	20h11m	–	0.65
2024-03-02	5h41m	6h15m	19h38m	20h12m	20h12m	1h09m	0.55
2024-03-03	5h40m	6h13m	19h39m	20h13m	20h13m	2h20m	0.44
2024-03-04	5h38m	6h12m	19h41m	20h15m	20h15m	3h28m	0.34
2024-03-05	5h36m	6h10m	19h42m	20h16m	20h16m	4h30m	0.23
2024-03-06	5h34m	6h08m	19h43m	20h17m	20h17m	5h22m	0.14
2024-03-07	5h32m	6h06m	19h45m	20h19m	20h19m	5h32m	0.07
2024-03-08	5h30m	6h05m	19h46m	20h20m	20h20m	5h30m	0.02
2024-03-09	5h29m	6h03m	19h47m	20h21m	20h21m	5h29m	0.00
			EDT
2024-03-10	6h27m	7h01m	20h48m	21h23m	21h23m	6h27m	0.01
2024-03-11	6h25m	6h59m	20h50m	21h24m	21h45m	6h25m	0.05
2024-03-12	6h23m	6h57m	20h51m	21h25m	23h07m	6h23m	0.12
2024-03-13	6h21m	6h55m	20h52m	21h27m	–	6h21m	0.20
2024-03-14	6h19m	6h54m	20h54m	21h28m	0h29m	6h19m	0.30
2024-03-15	6h17m	6h52m	20h55m	21h30m	1h48m	6h17m	0.40
2024-03-16	6h15m	6h50m	20h56m	21h31m	3h02m	6h15m	0.51
2024-03-17	6h13m	6h48m	20h58m	21h32m	4h07m	6h13m	0.61
2024-03-18	6h11m	6h46m	20h59m	21h34m	5h00m	6h11m	0.70
2024-03-19	6h09m	6h44m	21h00m	21h35m	5h41m	6h09m	0.78
2024-03-20	6h07m	6h42m	21h02m	21h37m	–	–	0.86
2024-03-21	6h05m	6h40m	21h03m	21h38m	–	–	0.92
2024-03-22	6h03m	6h38m	21h04m	21h40m	–	–	0.96
2024-03-23	6h01m	6h36m	21h06m	21h41m	–	–	0.99
2024-03-24	5h59m	6h34m	21h07m	21h43m	–	–	1.00
2024-03-25	5h57m	6h32m	21h08m	21h44m	–	–	0.99
2024-03-26	5h55m	6h30m	21h10m	21h46m	–	–	0.97
2024-03-27	5h53m	6h28m	21h11m	21h47m	21h47m	22h51m	0.92
2024-03-28	5h50m	6h26m	21h13m	21h49m	21h49m	0h00m	0.86
2024-03-29	5h48m	6h24m	21h14m	21h50m	21h50m	–	0.79
2024-03-30	5h46m	6h22m	21h15m	21h52m	21h52m	1h10m	0.70
2024-03-31	5h44m	6h20m	21h17m	21h53m	21h53m	2h18m	0.60

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2019/09/27/

NASA Calendar of Planetary Events

     Date   Time EST  Event
Mar  1  Fr            Venus: 24.3° W
     3  Su   3:16 am  Moon-Antares:  .4° S
     3  Su  10:24 am  Last Quarter
     4  Mo   9:03 pm  Moon South Dec.: 28.5° S
     7  Th  11:59 pm  Moon-Mars: 3.5° N
     8  Fr  12:01 pm  Moon-Venus: 3.2° N
            Time EDT
    10  Su   2:06 am  Moon Perigee: 356900 km
    10  Su   4:00 am  New Moon
    11  Mo   9:18 pm  Moon Ascending Node
    13  We   9:01 pm  Moon-Jupiter: 3.6° S
    14  Th  10:54 pm  Moon-Pleiades:  .4° N
    17  Su  12:11 am  First Quarter
    17  Su   6:31 am  Neptune Conjunction
    17  Su  10:45 am  Moon North Dec.: 28.5° N
    19  Tu   2:44 am  Moon-Pollux: 1.6° N
    19  Tu  11:07 pm  Vernal Equinox
    20  We   4:03 am  Moon-Beehive: 3.8° S
    21  Th   6:06 pm  Venus-Saturn:  .3° N
    23  Sa  11:44 am  Moon Apogee: 406300 km
    24  Su   5:59 pm  Mercury Elongation: 18.7° E
    25  Mo   3:00 am  Full Moon
    25  Mo   3:13 am  Penumbral Lunar Eclipse
    26  Tu  12:07 am  Moon Descending Node
    26  Tu   3:40 pm  Moon-Spica: 1.6° S
    30  Sa  10:24 am  Moon-Antares:  .3° S
Apr  1  Mo    Venus: 16.8° W

All event times are given for UTC-5:00: Eastern Standard Time before the 10th or UTC-4:00 Daylight Saving Time thereafter.

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

If you go to the above site you can print out a list like the above for the entire year or calendar pages for your time zone.

Note that the site is now kept up for archival purposes. Fred Espenak retired from NASA several years ago and has his own site, AstroPixels, which contain the same information: http://astropixels.com/almanac/almanac.html.

Sun and Moon Rising and Setting Events

LU              Ephemeris of Sky Events for Interlochen/TC
March, 2024    Local time zone: EST
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Fri  1| 07:19a  06:31p  11:11 | 07:34p  06:16a |      Rise 01:09a   66%|
|Sat  2| 07:17a  06:32p  11:15 | 07:35p  06:14a |      Rise 02:19a   57%|
+------+-----------------------+----------------+-----------------------+
|Sun  3| 07:15a  06:34p  11:18 | 07:37p  06:12a |L Qtr Rise 03:28a   46%|
|Mon  4| 07:14a  06:35p  11:21 | 07:38p  06:11a |      Rise 04:30a   36%|
|Tue  5| 07:12a  06:36p  11:24 | 07:39p  06:09a |      Rise 05:22a   26%|
|Wed  6| 07:10a  06:37p  11:27 | 07:41p  06:07a |      Rise 06:03a   16%|
|Thu  7| 07:08a  06:39p  11:30 | 07:42p  06:05a |      Rise 06:35a    8%|
|Fri  8| 07:06a  06:40p  11:33 | 07:43p  06:04a |      Rise 07:01a    3%|
|Sat  9| 07:05a  06:41p  11:36 | 07:44p  06:02a |      Rise 07:24a    0%|
+------+-----------------------+----------------+-----------------------+
| EDT  |      Time Change      |                |                       |
|Sun 10| 08:03a  07:43p  11:39 | 08:46p  07:00a |New   Set  08:22p    1%|
|Mon 11| 08:01a  07:44p  11:43 | 08:47p  06:58a |      Set  09:44p    4%|
|Tue 12| 07:59a  07:45p  11:46 | 08:48p  06:56a |      Set  11:07p   10%|
|Wed 13| 07:57a  07:47p  11:49 | 08:50p  06:54a |      Set  12:28a   18%|
|Thu 14| 07:55a  07:48p  11:52 | 08:51p  06:53a |      Set  01:47a   28%|
|Fri 15| 07:54a  07:49p  11:55 | 08:52p  06:51a |      Set  03:01a   38%|
|Sat 16| 07:52a  07:50p  11:58 | 08:54p  06:49a |      Set  04:06a   48%|
+------+-----------------------+----------------+-----------------------+
|Sun 17| 07:50a  07:52p  12:01 | 08:55p  06:47a |F Qtr Set  04:59a   58%|
|Mon 18| 07:48a  07:53p  12:04 | 08:56p  06:45a |      Set  05:41a   68%|
|Tue 19| 07:46a  07:54p  12:08 | 08:58p  06:43a |      Set  06:13a   77%|
|Wed 20| 07:44a  07:56p  12:11 | 08:59p  06:41a |      Set  06:38a   84%|
|Thu 21| 07:43a  07:57p  12:14 | 09:00p  06:39a |      Set  06:59a   91%|
|Fri 22| 07:41a  07:58p  12:17 | 09:02p  06:37a |      Set  07:16a   95%|
|Sat 23| 07:39a  07:59p  12:20 | 09:03p  06:35a |      Set  07:32a   98%|
+------+-----------------------+----------------+-----------------------+
|Sun 24| 07:37a  08:01p  12:23 | 09:04p  06:33a |      Set  07:48a  100%|
|Mon 25| 07:35a  08:02p  12:26 | 09:06p  06:31a |Full  Rise 08:39p  100%|
|Tue 26| 07:33a  08:03p  12:29 | 09:07p  06:29a |      Rise 09:44p   97%|
|Wed 27| 07:31a  08:04p  12:33 | 09:09p  06:27a |      Rise 10:50p   93%|
|Thu 28| 07:30a  08:06p  12:36 | 09:10p  06:25a |      Rise 11:59p   88%|
|Fri 29| 07:28a  08:07p  12:39 | 09:11p  06:23a |      Rise 01:09a   80%|
|Sat 30| 07:26a  08:08p  12:42 | 09:13p  06:21a |      Rise 02:18a   72%|
+------+-----------------------+----------------+-----------------------+
|Sun 31| 07:24a  08:09p  12:45 | 09:14p  06:19a |      Rise 03:21a   62%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset

Created using my LookingUp for DOS output as text.