Archive

Posts Tagged ‘September 2023’

Ephemeris: 08/31/2023 – Looking ahead to September’s skies

August 31, 2023 Comments off

This is Ephemeris for Thursday, August 31st. Today the Sun will be up for 13 hours and 17 minutes, setting at 8:21, and it will rise tomorrow at 7:04. The Moon, 1 day past full, will rise at 9:02 this evening.

Let’s look at the skies of September which starts tomorrow. The Sun will be moving at its greatest speed in its retreat to the south. Daylight hours in the Interlochen/Traverse City area will drop from 13 hours and 14 minutes tomorrow to 11 hours 46 minutes on the 30th. The altitude of the Sun above the southern horizon at local noon will be 53 degrees tomorrow, and will descend to 42 degrees on the 30th. The Straits* area will see the Sun a degree lower. The season of summer is getting short, so enjoy it while you can. Summer ends and fall begins at 12:50 a.m. on the 23rd, the autumnal equinox. Venus is our brilliant Morning Star now, And on the 29th we’ll have the Harvest Moon, the nearest full moon to the autumnal equinox. There is a comet approaching the Sun in the first half of September, It will be described in an Ephemeris Extra later today.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

*For those not familiar with our area the Straits refer to the Straits of Mackinac (pronounced Mackinaw) that separate the Upper and Lower Peninsulas of Michigan.

Addendum

September Evening Star Chart

Star Chart for September 2023. Click or tap on the image to enlarge it. Created using my LookingUp program.

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, West 75° longitude. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.

September Morning Star Chart

Star Chart for September 2023 (6 am EDT, September 15, 2022). Click on the image to enlarge it. Created using my LookingUp program.

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.
  • Leaky dipper drips on Leo.
  • Follow the arc of the handle of the Big Dipper to the star Arcturus.
  • The Summer Triangle is in red.

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning Twilight Evening Twilight Dark Night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2023-09-01 5h26m 6h04m 21h29m 22h08m – – 0.93
2023-09-02 5h27m 6h05m 21h27m 22h05m – – 0.86
2023-09-03 5h29m 6h07m 21h25m 22h03m 22h03m 22h07m 0.78
2023-09-04 5h30m 6h08m 21h23m 22h01m 22h01m 22h33m 0.68
2023-09-05 5h32m 6h09m 21h21m 21h59m 21h59m 23h03m 0.57
2023-09-06 5h34m 6h11m 21h19m 21h56m 21h56m 23h41m 0.47
2023-09-07 5h35m 6h12m 21h17m 21h54m 21h54m – 0.37
2023-09-08 5h37m 6h13m 21h15m 21h52m 21h52m 0h27m 0.28
2023-09-09 5h38m 6h15m 21h13m 21h50m 21h50m 1h21m 0.20
2023-09-10 5h40m 6h16m 21h11m 21h48m 21h48m 2h22m 0.13
2023-09-11 5h41m 6h17m 21h09m 21h46m 21h46m 3h27m 0.07
2023-09-12 5h42m 6h19m 21h07m 21h43m 21h43m 4h32m 0.03
2023-09-13 5h44m 6h20m 21h05m 21h41m 21h41m 5h38m 0.01
2023-09-14 5h45m 6h21m 21h03m 21h39m 21h39m 5h45m 0.00
2023-09-15 5h47m 6h23m 21h01m 21h37m 21h37m 5h47m 0.01
2023-09-16 5h48m 6h24m 20h59m 21h35m 21h35m 5h48m 0.04
2023-09-17 5h50m 6h25m 20h57m 21h33m 21h33m 5h50m 0.09
2023-09-18 5h51m 6h27m 20h55m 21h31m 21h31m 5h51m 0.16
2023-09-19 5h52m 6h28m 20h53m 21h28m 21h39m 5h52m 0.24
2023-09-20 5h54m 6h29m 20h51m 21h26m 22h10m 5h54m 0.33
2023-09-21 5h55m 6h30m 20h49m 21h24m 22h52m 5h55m 0.44
2023-09-22 5h57m 6h32m 20h47m 21h22m 23h46m 5h57m 0.55
2023-09-23 5h58m 6h33m 20h45m 21h20m – 5h58m 0.66
2023-09-24 5h59m 6h34m 20h43m 21h18m 0h53m 5h59m 0.76
2023-09-25 6h01m 6h35m 20h41m 21h16m 2h11m 6h01m 0.85
2023-09-26 6h02m 6h37m 20h39m 21h14m 3h35m 6h02m 0.93
2023-09-27 6h03m 6h38m 20h37m 21h12m 4h59m 6h03m 0.98
2023-09-28 6h05m 6h39m 20h36m 21h10m – – 1.00
2023-09-29 6h06m 6h40m 20h34m 21h08m – – 0.99
2023-09-30 6h07m 6h42m 20h32m 21h06m – – 0.96

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/2018/09/27/.

NASA Calendar of Planetary Events

Date         Time     Event
Sep  1  Fr            Venus: 27.4° W
     3  Su   3:44 am  Moon Ascending Node
     4  Mo   3:44 pm  Moon-Jupiter: 3.4° S
     5  Tu   3:25 pm  Moon-Pleiades: 1.3° N
     6  We   7:03 am  Mercury Inferior Conj.
     6  We   6:21 pm  Last Quarter
     8  Fr   9:18 am  Moon North Dec.: 28.2° N
     9  Sa  11:32 pm  Moon-Pollux: 1.7° N
    12  Tu  11:42 am  Moon Apogee: 406,300 km
    14  Th   9:40 pm  New Moon
    17  Su  11:12 am  Moon-Spica: 2.6° S
    17  Su   3:18 pm  Moon Descending Node
    19  Tu            Venus greatest brilliancy
    19  Tu   5:54 am  Neptune Opposition
    21  Th   3:50 am  Moon-Antares:  0.9° S
    22  Fr   8:59 am  Mercury Elongation: 17.9° W
                      Favorable greatest elongation for
                      the Northern Hemisphere.
    22  Fr   3:32 pm  First Quarter
    22  Fr  11:42 pm  Moon South Dec.: 28.3° S
    23  Sa   2:50 am  Autumnal Equinox
    26  Tu   9:25 pm  Moon-Saturn: 2.6° N
    27  We   9:05 pm  Moon Perigee: 359,900 km
    29  Fr   5:57 am  Full Harvest Moon
    30  Sa  12:49 pm  Moon Ascending Node
Oct  1  Su            Venus: 44.2° W

All event times are given for UTC-4 hr: Eastern Daylight Saving Time.

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.

Sun and Moon Rising and Setting Events

                Ephemeris of Sky Events for Interlochen/TC
September 2023    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Fri  1| 07:04a  08:19p  13:14 | 09:26p  05:58a |      Rise 09:24p   94%|
|Sat  2| 07:06a  08:18p  13:11 | 09:24p  05:59a |      Rise 09:45p   88%|
+------+-----------------------+----------------+-----------------------+
|Sun  3| 07:07a  08:16p  13:08 | 09:21p  06:01a |      Rise 10:07p   79%|
|Mon  4| 07:08a  08:14p  13:05 | 09:19p  06:02a |      Rise 10:32p   70%|
|Tue  5| 07:09a  08:12p  13:02 | 09:17p  06:03a |      Rise 11:03p   60%|
|Wed  6| 07:10a  08:10p  12:59 | 09:15p  06:05a |L Qtr Rise 11:40p   49%|
|Thu  7| 07:12a  08:08p  12:56 | 09:13p  06:06a |      Rise 12:26a   39%|
|Fri  8| 07:13a  08:06p  12:53 | 09:11p  06:08a |      Rise 01:20a   30%|
|Sat  9| 07:14a  08:05p  12:50 | 09:09p  06:09a |      Rise 02:21a   22%|
+------+-----------------------+----------------+-----------------------+
|Sun 10| 07:15a  08:03p  12:47 | 09:07p  06:10a |      Rise 03:26a   14%|
|Mon 11| 07:16a  08:01p  12:44 | 09:05p  06:12a |      Rise 04:32a    8%|
|Tue 12| 07:17a  07:59p  12:41 | 09:03p  06:13a |      Rise 05:37a    4%|
|Wed 13| 07:19a  07:57p  12:38 | 09:01p  06:14a |      Rise 06:41a    1%|
|Thu 14| 07:20a  07:55p  12:35 | 08:59p  06:15a |New   Set  08:04p    0%|
|Fri 15| 07:21a  07:53p  12:32 | 08:57p  06:17a |      Set  08:20p    1%|
|Sat 16| 07:22a  07:51p  12:29 | 08:55p  06:18a |      Set  08:36p    3%|
+------+-----------------------+----------------+-----------------------+
|Sun 17| 07:23a  07:50p  12:26 | 08:53p  06:19a |      Set  08:54p    8%|
|Mon 18| 07:24a  07:48p  12:23 | 08:51p  06:21a |      Set  09:14p   14%|
|Tue 19| 07:26a  07:46p  12:20 | 08:49p  06:22a |      Set  09:39p   22%|
|Wed 20| 07:27a  07:44p  12:17 | 08:47p  06:23a |      Set  10:10p   31%|
|Thu 21| 07:28a  07:42p  12:13 | 08:45p  06:24a |      Set  10:51p   41%|
|Fri 22| 07:29a  07:40p  12:10 | 08:43p  06:26a |F Qtr Set  11:45p   52%|
|Sat 23| 07:30a  07:38p  12:07 | 08:41p  06:27a |      Set  12:52a   63%|
+------+-----------------------+----------------+-----------------------+
|Sun 24| 07:32a  07:36p  12:04 | 08:39p  06:28a |      Set  02:11a   74%|
|Mon 25| 07:33a  07:34p  12:01 | 08:38p  06:30a |      Set  03:34a   84%|
|Tue 26| 07:34a  07:33p  11:58 | 08:36p  06:31a |      Set  04:59a   91%|
|Wed 27| 07:35a  07:31p  11:55 | 08:34p  06:32a |      Set  06:22a   97%|
|Thu 28| 07:36a  07:29p  11:52 | 08:32p  06:33a |      Set  07:43a  100%|
|Fri 29| 07:38a  07:27p  11:49 | 08:30p  06:35a |Full  Rise 07:45p   99%|
|Sat 30| 07:39a  07:25p  11:46 | 08:28p  06:36a |      Rise 08:07p   96%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset

Generated using my LookingUp for DOS program.

Categories: Ephemeris Program, Month preview, Observing Tags: