Archive
08/01/2019 – Ephemeris – Previewing August skies
Ephemeris for Thursday, August 1st. Today the Sun will be up for 14 hours and 40 minutes, setting at 9:08, and it will rise tomorrow at 6:29. The Moon, 1 day past new, will set at 9:54 this evening.
Let’s look ahead at the month of August. Daylight hours will decrease from 14 hours and 40 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 horizon will decrease from 63 degrees today to just over 53 degrees on the 31st. Straits area listeners can subtract one 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 during the morning hours of the 13th, by then the Moon will be nearly full. On the nights between now and then when the moon has set these meteor numbers will be building to the peak. Jupiter and Saturn will be our easily visible evening planets.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
August Evening Star Chart

Star Chart for August 2019 (10 p.m. EDT August 15, 2019). Click on image to enlarge.Created using my LookingUp program. Click on image to enlarge.
The planets and stars are plotted for the 15th at 10 p.m. EDT in the evening and 5 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.
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. For planet positions on dates other than the 15th.
August Morning Star Chart

Star Chart for August mornings 2019 (5 a.m. EDT August 15, 2019). Click on image to enlarge. 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, 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 13th)
Twilight Limits, Nautical and Astronomical
| EDT | |||||||
| Traverse City |
Morning twilight | Evening twilight | Dark night | Moon | |||
| Date | Astro. | Nautical | Nautical | Astro. | Start | End | Illum. |
| 2019-08-01 | 4h30m | 5h18m | 22h27m | 23h16m | 23h16m | 4h30m | 0.01 |
| 2019-08-02 | 4h31m | 5h20m | 22h26m | 23h14m | 23h14m | 4h31m | 0.04 |
| 2019-08-03 | 4h33m | 5h21m | 22h24m | 23h12m | 23h12m | 4h33m | 0.11 |
| 2019-08-04 | 4h35m | 5h23m | 22h22m | 23h10m | 23h33m | 4h35m | 0.2 |
| 2019-08-05 | 4h37m | 5h24m | 22h21m | 23h07m | – | 4h37m | 0.3 |
| 2019-08-06 | 4h39m | 5h26m | 22h19m | 23h05m | 0h01m | 4h39m | 0.42 |
| 2019-08-07 | 4h41m | 5h27m | 22h17m | 23h03m | 0h30m | 4h41m | 0.53 |
| 2019-08-08 | 4h43m | 5h29m | 22h15m | 23h01m | 1h00m | 4h43m | 0.64 |
| 2019-08-09 | 4h45m | 5h30m | 22h14m | 22h59m | 1h33m | 4h45m | 0.74 |
| 2019-08-10 | 4h47m | 5h32m | 22h12m | 22h57m | 2h11m | 4h47m | 0.83 |
| 2019-08-11 | 4h49m | 5h33m | 22h10m | 22h54m | 2h54m | 4h49m | 0.9 |
| 2019-08-12 | 4h51m | 5h35m | 22h08m | 22h52m | 3h44m | 4h51m | 0.9 |
| 2019-08-13 | 4h52m | 5h36m | 22h06m | 22h50m | 4h38m | 4h52m | 0.95 |
| 2019-08-14 | 4h54m | 5h38m | 22h04m | 22h48m | – | – | 0.98 |
| 2019-08-15 | 4h56m | 5h39m | 22h03m | 22h46m | – | – | 1 |
| 2019-08-16 | 4h58m | 5h41m | 22h01m | 22h43m | – | – | 0.99 |
| 2019-08-17 | 5h00m | 5h42m | 21h59m | 22h41m | – | – | 0.97 |
| 2019-08-18 | 5h01m | 5h43m | 21h57m | 22h39m | – | – | 0.93 |
| 2019-08-19 | 5h03m | 5h45m | 21h55m | 22h37m | 22h37m | 22h53m | 0.87 |
| 2019-08-20 | 5h05m | 5h46m | 21h53m | 22h34m | 22h34m | 23h16m | 0.8 |
| 2019-08-21 | 5h07m | 5h48m | 21h51m | 22h32m | 22h32m | 23h41m | 0.72 |
| 2019-08-22 | 5h08m | 5h49m | 21h49m | 22h30m | 22h30m | – | 0.62 |
| 2019-08-23 | 5h10m | 5h51m | 21h47m | 22h28m | 22h28m | 0h10m | 0.52 |
| 2019-08-24 | 5h12m | 5h52m | 21h45m | 22h25m | 22h25m | 0h43m | 0.41 |
| 2019-08-25 | 5h14m | 5h54m | 21h43m | 22h23m | 22h23m | 1h23m | 0.3 |
| 2019-08-26 | 5h15m | 5h55m | 21h41m | 22h21m | 22h21m | 2h13m | 0.2 |
| 2019-08-27 | 5h17m | 5h56m | 21h39m | 22h19m | 22h19m | 3h13m | 0.11 |
| 2019-08-28 | 5h19m | 5h58m | 21h37m | 22h16m | 22h16m | 4h23m | 0.05 |
| 2019-08-29 | 5h20m | 5h59m | 21h35m | 22h14m | 22h14m | 5h20m | 0.01 |
| 2019-08-30 | 5h22m | 6h01m | 21h33m | 22h12m | 22h12m | 5h22m | 0 |
| 2019-08-31 | 5h24m | 6h02m | 21h31m | 22h10m | 22h10m | 5h24m | 0.03 |
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
Aug 1 Th Venus: 3.6° W 2 Fr 3:08 am Moon Perigee: 359400 km 7 We 1:31 pm First Quarter 9 Fr 6:53 pm Moon-Jupiter: 2.6° S 9 Fr 6:59 pm Mercury Elongation: 19° W 12 Mo 12:28 am Moon South Dec.: 22.4° S 12 Mo 6:05 am Moon-Saturn: 0° 12 Mo 10:45 am Moon Descending Node 12 Mo 12:29 pm Jupiter-Antares: 6.9° N 13 Tu 2:53 am Perseid Shower: ZHR = 90 14 We 1:44 am Venus Superior Conj. 15 Th 8:29 am Full Moon 17 Sa 12:24 am Mercury-Beehive: 1.2° S 17 Sa 6:50 am Moon Apogee: 406200 km 23 Fr 10:56 am Last Quarter 24 Sa 5:24 am Moon-Aldebaran: 2.5° S 26 Mo 1:53 pm Moon North Dec.: 22.5° N 26 Mo 9:50 pm Moon Ascending Node 28 We 7:31 am Moon-Beehive: 0.2° S 30 Fr 6:37 am New Moon 30 Fr 11:57 am Moon Perigee: 357200 km Sep 1 Su Venus: 5.2° E
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
LU Ephemeris of Sky Events for Interlochen/TC
August, 2019 Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Thu 1| 06:28a 09:08p 14:40 | 10:24p 05:12a | Set 09:54p 1%|
|Fri 2| 06:29a 09:07p 14:37 | 10:22p 05:14a | Set 10:31p 5%|
|Sat 3| 06:31a 09:06p 14:35 | 10:20p 05:15a | Set 11:03p 12%|
+------+-----------------------+----------------+-----------------------+
|Sun 4| 06:32a 09:04p 14:32 | 10:19p 05:17a | Set 11:33p 21%|
|Mon 5| 06:33a 09:03p 14:30 | 10:17p 05:18a | Set 12:01a 31%|
|Tue 6| 06:34a 09:02p 14:27 | 10:15p 05:20a | Set 12:29a 42%|
|Wed 7| 06:35a 09:00p 14:25 | 10:14p 05:21a |F Qtr Set 01:00a 53%|
|Thu 8| 06:36a 08:59p 14:22 | 10:12p 05:23a | Set 01:33a 64%|
|Fri 9| 06:37a 08:57p 14:20 | 10:10p 05:24a | Set 02:11a 73%|
|Sat 10| 06:39a 08:56p 14:17 | 10:08p 05:26a | Set 02:54a 82%|
+------+-----------------------+----------------+-----------------------+
|Sun 11| 06:40a 08:55p 14:14 | 10:06p 05:27a | Set 03:44a 89%|
|Mon 12| 06:41a 08:53p 14:12 | 10:05p 05:29a | Set 04:38a 94%|
|Tue 13| 06:42a 08:51p 14:09 | 10:03p 05:30a | Set 05:36a 98%|
|Wed 14| 06:43a 08:50p 14:06 | 10:01p 05:32a | Set 06:36a 100%|
|Thu 15| 06:44a 08:48p 14:03 | 09:59p 05:33a |Full Rise 09:17p 100%|
|Fri 16| 06:46a 08:47p 14:01 | 09:57p 05:35a | Rise 09:44p 98%|
|Sat 17| 06:47a 08:45p 13:58 | 09:55p 05:36a | Rise 10:08p 94%|
+------+-----------------------+----------------+-----------------------+
|Sun 18| 06:48a 08:44p 13:55 | 09:53p 05:38a | Rise 10:31p 89%|
|Mon 19| 06:49a 08:42p 13:52 | 09:51p 05:39a | Rise 10:53p 83%|
|Tue 20| 06:50a 08:40p 13:49 | 09:49p 05:41a | Rise 11:16p 75%|
|Wed 21| 06:51a 08:39p 13:47 | 09:47p 05:42a | Rise 11:41p 66%|
|Thu 22| 06:53a 08:37p 13:44 | 09:46p 05:44a | Rise 12:10a 56%|
|Fri 23| 06:54a 08:35p 13:41 | 09:44p 05:45a |L Qtr Rise 12:43a 46%|
|Sat 24| 06:55a 08:34p 13:38 | 09:42p 05:47a | Rise 01:24a 36%|
+------+-----------------------+----------------+-----------------------+
|Sun 25| 06:56a 08:32p 13:35 | 09:40p 05:48a | Rise 02:13a 26%|
|Mon 26| 06:57a 08:30p 13:32 | 09:38p 05:50a | Rise 03:13a 16%|
|Tue 27| 06:59a 08:28p 13:29 | 09:36p 05:51a | Rise 04:23a 9%|
|Wed 28| 07:00a 08:27p 13:26 | 09:34p 05:52a | Rise 05:40a 3%|
|Thu 29| 07:01a 08:25p 13:23 | 09:32p 05:54a | Rise 07:00a 0%|
|Fri 30| 07:02a 08:23p 13:20 | 09:30p 05:55a |New Set 08:59p 1%|
|Sat 31| 07:03a 08:21p 13:17 | 09:28p 05:57a | Set 09:31p 4%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset
Generated using my LookingUp for DOS program.