Archive
Ephemeris: 08/01/2023 – Looking ahead to August skies
This is Ephemeris for Tuesday, August 1st. Today the Sun will be up for 14 hours and 39 minutes, setting at 9:08, and it will rise tomorrow at 6:29. The Moon, at full today, will rise at 9:44 this evening.
Let’s look ahead at the month of August in the skies. Daylight hours will decrease from 14 hours and 39 minutes today to 13 hours 17 minutes on the 31st. The altitude of the Sun at local noon, that is degrees of angle above the southern horizon, will decrease from 63 degrees today to just over 53 degrees on the 31st. Straits area listeners can subtract one more degree from those angles. Local noon, when the Sun is due south, is about 1:43 p.m. The Perseid meteor shower will reach its peak on the morning of the13th. The Moon will not interfere until it rises at 3:39 am, but then it’s only a waning crescent. A few Perseid meteors can be seen even now, nearly two weeks before the peak. They will seem to come from the northeastern part of the sky.
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.
Addendum
August Evening Star Chart
The planets and stars are plotted for the 15th at 10 pm EDT in the evening and 5 am. 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.
Note the chart times 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. The planet positions are updated each Wednesday on this blog. See them for planet positions on dates other than the 15th.
August 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.
- Leaky dipper drips on Leo.
- Follow the arc of the handle of the Big Dipper to the star Arcturus, and
- Extend like a spike to Spica.
- The Summer Triangle is in red.
- PerR is the radiant of the Perseid meteor shower (Peaks on the morning of the 13th)
Twilight Limits, Nautical and Astronomical
| EDT | |||||||
| Morning | Twilight | Evening | Twilight | Dark | Night | Moon | |
| Date | Astro. | Nautical | Nautical | Astro. | Start | End | Illum. |
| 2023-08-01 | 4h30m | 5h19m | 22h27m | 23h16m | – | – | 1.00 |
| 2023-08-02 | 4h32m | 5h20m | 22h26m | 23h14m | – | – | 0.97 |
| 2023-08-03 | 4h34m | 5h22m | 22h24m | 23h12m | – | – | 0.91 |
| 2023-08-04 | 4h36m | 5h23m | 22h22m | 23h09m | – | – | 0.83 |
| 2023-08-05 | 4h38m | 5h25m | 22h21m | 23h07m | 23h07m | 23h23m | 0.74 |
| 2023-08-06 | 4h40m | 5h26m | 22h19m | 23h05m | 23h05m | 23h43m | 0.63 |
| 2023-08-07 | 4h42m | 5h28m | 22h17m | 23h03m | 23h03m | – | 0.52 |
| 2023-08-08 | 4h44m | 5h29m | 22h15m | 23h01m | 23h01m | 0h06m | 0.42 |
| 2023-08-09 | 4h46m | 5h31m | 22h14m | 22h59m | 22h59m | 0h32m | 0.32 |
| 2023-08-10 | 4h47m | 5h32m | 22h12m | 22h57m | 22h57m | 1h04m | 0.23 |
| 2023-08-11 | 4h49m | 5h34m | 22h10m | 22h54m | 22h54m | 1h44m | 0.15 |
| 2023-08-12 | 4h51m | 5h35m | 22h08m | 22h52m | 22h52m | 2h32m | 0.09 |
| 2023-08-13 | 4h53m | 5h37m | 22h06m | 22h50m | 22h50m | 3h28m | 0.04 |
| 2023-08-14 | 4h55m | 5h38m | 22h05m | 22h48m | 22h48m | 4h31m | 0.01 |
| 2023-08-15 | 4h57m | 5h40m | 22h03m | 22h46m | 22h46m | 4h57m | 0.00 |
| 2023-08-16 | 4h58m | 5h41m | 22h01m | 22h43m | 22h43m | 4h58m | 0.01 |
| 2023-08-17 | 5h00m | 5h43m | 21h59m | 22h41m | 22h41m | 5h00m | 0.03 |
| 2023-08-18 | 5h02m | 5h44m | 21h57m | 22h39m | 22h39m | 5h02m | 0.07 |
| 2023-08-19 | 5h04m | 5h45m | 21h55m | 22h37m | 22h37m | 5h04m | 0.13 |
| 2023-08-20 | 5h06m | 5h47m | 21h53m | 22h34m | 22h34m | 5h06m | 0.20 |
| 2023-08-21 | 5h07m | 5h48m | 21h51m | 22h32m | 22h49m | 5h07m | 0.28 |
| 2023-08-22 | 5h09m | 5h50m | 21h49m | 22h30m | 23h10m | 5h09m | 0.38 |
| 2023-08-23 | 5h11m | 5h51m | 21h47m | 22h28m | 23h37m | 5h11m | 0.48 |
| 2023-08-24 | 5h13m | 5h53m | 21h45m | 22h25m | – | 5h13m | 0.59 |
| 2023-08-25 | 5h14m | 5h54m | 21h43m | 22h23m | 0h12m | 5h14m | 0.69 |
| 2023-08-26 | 5h16m | 5h56m | 21h41m | 22h21m | 0h58m | 5h16m | 0.79 |
| 2023-08-27 | 5h18m | 5h57m | 21h39m | 22h19m | 2h00m | 5h18m | 0.88 |
| 2023-08-28 | 5h19m | 5h58m | 21h37m | 22h17m | 3h15m | 5h19m | 0.95 |
| 2023-08-29 | 5h21m | 6h00m | 21h35m | 22h14m | 4h39m | 5h21m | 0.99 |
| 2023-08-30 | 5h22m | 6h01m | 21h33m | 22h12m | – | – | 1.00 |
| 2023-08-31 | 5h24m | 6h03m | 21h31m | 22h10m | – | – | 0.98 |
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
Aug 1 Tu Venus: 18.7° E
1 Tu 2:31 pm Full Sturgeon Moon
2 We 1:52 am Moon Perigee: 357,300 km
3 Th 6:21 am Moon-Saturn: 2.4° N
6 Su 10:46 pm Moon Ascending Node
8 Tu 5:41 am Moon-Jupiter: 3° S
8 Tu 6:28 am Last Quarter
9 We 8:16 am Moon-Pleiades: 1.6° N
9 We 9:59 pm Mercury Elongation: 27.4° E
12 Sa 3:39 am Moon North Dec.: 28° N
13 Su 3:02 am Mercury-Mars: 4.7° N
13 Su 3:29 am Perseid Meteor Shower: ZHR = 90
13 Su 7:10 am Venus Inferior Conj.
13 Su 5:36 pm Moon-Pollux: 1.9° N
16 We 5:38 am New Moon
16 We 7:55 am Moon Apogee: 406,600 km
18 Fr 7:06 pm Moon-Mars: 2.4° S
21 Mo 5:28 am Moon-Spica: 2.8° S
21 Mo 12:23 pm Moon Descending Node
24 Th 5:57 am First Quarter
24 Th 9:30 pm Moon-Antares: 1.1° S
26 Sa 4:22 pm Moon South Dec.: 28.1° S
27 Su 3:52 am Saturn Opposition
30 We 11:51 am Moon Perigee: 357,200 km
30 We 2:03 pm Moon-Saturn: 2.4° N
30 We 9:35 pm Full Blue Moon
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
LU Ephemeris of Sky Events for Interlochen/TC
August 2023 Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Tue 1| 06:28a 09:08p 14:39 | 11:12p 04:24a |Full Rise 09:44p 100%|
|Wed 2| 06:29a 09:07p 14:37 | 11:10p 04:26a | Rise 10:15p 98%|
|Thu 3| 06:31a 09:06p 14:35 | 11:08p 04:28a | Rise 10:40p 92%|
|Fri 4| 06:32a 09:04p 14:32 | 11:06p 04:30a | Rise 11:02p 85%|
|Sat 5| 06:33a 09:03p 14:30 | 11:04p 04:31a | Rise 11:22p 76%|
+------+-----------------------+----------------+-----------------------+
|Sun 6| 06:34a 09:02p 14:27 | 11:01p 04:33a | Rise 11:43p 65%|
|Mon 7| 06:35a 09:00p 14:25 | 10:59p 04:35a | Rise 12:06a 55%|
|Tue 8| 06:36a 08:59p 14:22 | 10:57p 04:37a |L Qtr Rise 12:32a 44%|
|Wed 9| 06:37a 08:57p 14:19 | 10:55p 04:39a | Rise 01:04a 34%|
|Thu 10| 06:39a 08:56p 14:17 | 10:53p 04:41a | Rise 01:43a 25%|
|Fri 11| 06:40a 08:54p 14:14 | 10:51p 04:43a | Rise 02:32a 17%|
|Sat 12| 06:41a 08:53p 14:12 | 10:48p 04:45a | Rise 03:28a 10%|
+------+-----------------------+----------------+-----------------------+
|Sun 13| 06:42a 08:51p 14:09 | 10:46p 04:47a | Rise 04:30a 5%|
|Mon 14| 06:43a 08:50p 14:06 | 10:44p 04:48a | Rise 05:35a 2%|
|Tue 15| 06:44a 08:48p 14:03 | 10:42p 04:50a | Rise 06:41a 0%|
|Wed 16| 06:46a 08:47p 14:01 | 10:40p 04:52a |New Set 09:21p 0%|
|Thu 17| 06:47a 08:45p 13:58 | 10:37p 04:54a | Set 09:40p 2%|
|Fri 18| 06:48a 08:44p 13:55 | 10:35p 04:56a | Set 09:57p 6%|
|Sat 19| 06:49a 08:42p 13:52 | 10:33p 04:57a | Set 10:13p 11%|
+------+-----------------------+----------------+-----------------------+
|Sun 20| 06:50a 08:40p 13:49 | 10:31p 04:59a | Set 10:30p 18%|
|Mon 21| 06:52a 08:39p 13:47 | 10:28p 05:01a | Set 10:48p 26%|
|Tue 22| 06:53a 08:37p 13:44 | 10:26p 05:03a | Set 11:09p 36%|
|Wed 23| 06:54a 08:35p 13:41 | 10:24p 05:05a | Set 11:36p 46%|
|Thu 24| 06:55a 08:33p 13:38 | 10:22p 05:06a |F Qtr Set 12:11a 56%|
|Fri 25| 06:56a 08:32p 13:35 | 10:19p 05:08a | Set 12:57a 67%|
|Sat 26| 06:57a 08:30p 13:32 | 10:17p 05:10a | Set 01:59a 77%|
+------+-----------------------+----------------+-----------------------+
|Sun 27| 06:59a 08:28p 13:29 | 10:15p 05:11a | Set 03:14a 86%|
|Mon 28| 07:00a 08:26p 13:26 | 10:13p 05:13a | Set 04:38a 93%|
|Tue 29| 07:01a 08:25p 13:23 | 10:10p 05:15a | Set 06:05a 98%|
|Wed 30| 07:02a 08:23p 13:20 | 10:08p 05:16a |Full Rise 08:39p 100%|
|Thu 31| 07:03a 08:21p 13:17 | 10:06p 05:18a | Rise 09:02p 99%|
+-----------------------------------------------------------------------+
* Astronomical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset
Generated using my LookingUp for DOS program.
Bob Moler's Ephemeris Blog 