Archive
08/01/2017 – Ephemeris – A look at the busy month of August in astronomy
Ephemeris for Tuesday, August 1st. The Sun rises at 6:29. It’ll be up for 14 hours and 38 minutes, setting at 9:07. The Moon, 2 days past first quarter, will set at 2:21 tomorrow morning.
Let’s look ahead at the month of August in the skies. Daylight hours will decrease from 14 hours and 38 minutes today to 13 hours 16 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. The Perseid meteor shower will reach its peak on the evening of the 12th. However the bright waning gibbous moon will rise just after 11:30 for a very short dark sky viewing period. The big event this month will be the total solar eclipse that will be visible from all 50 of the United States and total for a narrow strip of land stretching from Oregon to South Carolina. That will occur on the afternoon of Monday the 21st.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
August Evening Star Chart
Star Chart for August 2017 (10 p.m. August 15, 2017). 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. (An hour 45 minutes behind our daylight saving time meridian. during EDT and 45 minutes behind our daylight standard time meridian. during EST). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes (Daylight Time) or 45 minutes (Standard Time) earlier than the current time if you are near your time meridian.
Note the chart times of 10 p.m. and 5 a.m. are for the 15th. For each week before the 15th add ½ hour. For each week after the 15th subtract ½ hour. The planet positions are updated each Wednesday on this blog.
August Morning Star Chart
Star Chart for August 2017 mornings based on 5 a.m. August 15th. Created using my LookingUp program. Click on image to enlarge.
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 Big Dipper drips on Leo
- Follow the arc of the handle of the Big Dipper to the star Arcturus,
- Then follow the Spike to Spica
- The Summer Triangle is in red
- PerR is the Perseid Meteor Shower radiant
Evening nautical twilight ends at 10:26 p.m. EDT on the 1st, decreasing to 9:30 p.m. EDT on the 31st.
Evening astronomical twilight ends at 11:15 p.m. EDT on the 1st, decreasing to 10:09 p.m. EDT on the 31st.
Morning astronomical twilight starts at 4:30 a.m. EDT on the 1st, and increasing to 5:24 a.m. EDT on the 31st.
Morning nautical twilight starts at 5:19 a.m. EDT on the 1st, and increasing to 6:03 a.m. EDT on the 31st.
NASA Calendar of Planetary Events
Date Time Event
Aug 01 Tu Venus: 38.4° W
02 We 1:55 pm Moon Apogee: 405000 km
03 Th 3:31 am Moon-Saturn: 3.8° S
04 Fr 2:17 pm Moon South Dec.: 19.4° S
07 Mo 2:11 pm Full Moon
07 Mo 2:22 pm Partial Lunar Eclipse (Not visible from here)
08 Tu 6:56 am Moon Descending Node
12 Sa 2:35 pm Perseid Shower: ZHR = 90
14 Mo 9:15 pm Last Quarter
16 We 2:39 am Moon-Aldebaran: 0.4° S
18 Fr 2:50 am Moon North Dec.: 19.4° N
18 Fr 9:14 am Moon Perigee: 366100 km
19 Sa 12:45 am Moon-Venus: 2.3° N
20 Su 3:15 am Moon-Beehive: 3.2° N
21 Mo 6:34 am Moon Ascending Node
21 Mo 2:26 pm Total Solar Eclipse
21 Mo 2:30 pm New Moon
25 Fr 9:00 am Moon-Jupiter: 3.7° S
26 Sa 4:32 pm Mercury Inferior Conj.
29 Tu 4:13 am First Quarter
30 We 7:25 am Moon Apogee: 404300 km
30 We 10:23 am Moon-Saturn: 3.9° S
31 Th 10:03 pm Moon South Dec.: 19.4° S
Sep 01 Fr Venus: 31.7° W
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.
August Rising and Setting Events
LU Ephemeris of Sky Events for Interlochen/TC August, 2017 Local time zone: EDT +-----------------------------------------------------------------------+ | DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM | | | RISE SET HOURS | END START |PHASE SET** TIME FRACTN| +=======================================================================+ |Tue 1| 06:29a 09:08p 14:38 | 10:23p 05:13a | Set 02:21a 72%| |Wed 2| 06:30a 09:06p 14:36 | 10:21p 05:15a | Set 03:00a 80%| |Thu 3| 06:31a 09:05p 14:34 | 10:20p 05:16a | Set 03:43a 87%| |Fri 4| 06:32a 09:04p 14:31 | 10:18p 05:18a | Set 04:32a 93%| |Sat 5| 06:33a 09:02p 14:29 | 10:16p 05:19a | Set 05:26a 97%| +------+-----------------------+----------------+-----------------------+ |Sun 6| 06:34a 09:01p 14:26 | 10:15p 05:21a | Set 06:24a 99%| |Mon 7| 06:36a 09:00p 14:23 | 10:13p 05:22a |Full Rise 09:01p 100%| |Tue 8| 06:37a 08:58p 14:21 | 10:11p 05:24a | Rise 09:35p 98%| |Wed 9| 06:38a 08:57p 14:18 | 10:09p 05:25a | Rise 10:06p 95%| |Thu 10| 06:39a 08:55p 14:16 | 10:07p 05:27a | Rise 10:36p 89%| |Fri 11| 06:40a 08:54p 14:13 | 10:06p 05:28a | Rise 11:06p 81%| |Sat 12| 06:41a 08:52p 14:10 | 10:04p 05:30a | Rise 11:36p 72%| +------+-----------------------+----------------+-----------------------+ |Sun 13| 06:43a 08:51p 14:08 | 10:02p 05:31a | Rise 12:09a 62%| |Mon 14| 06:44a 08:49p 14:05 | 10:00p 05:33a |L Qtr Rise 12:46a 51%| |Tue 15| 06:45a 08:48p 14:02 | 09:58p 05:34a | Rise 01:28a 39%| |Wed 16| 06:46a 08:46p 13:59 | 09:56p 05:36a | Rise 02:16a 28%| |Thu 17| 06:47a 08:44p 13:57 | 09:54p 05:37a | Rise 03:13a 18%| |Fri 18| 06:49a 08:43p 13:54 | 09:52p 05:39a | Rise 04:16a 10%| |Sat 19| 06:50a 08:41p 13:51 | 09:50p 05:40a | Rise 05:24a 4%| +------+-----------------------+----------------+-----------------------+ |Sun 20| 06:51a 08:39p 13:48 | 09:48p 05:42a | Rise 06:35a 1%| |Mon 21| 06:52a 08:38p 13:45 | 09:47p 05:43a |New Set 08:44p 0%| |Tue 22| 06:53a 08:36p 13:42 | 09:45p 05:44a | Set 09:18p 2%| |Wed 23| 06:54a 08:34p 13:39 | 09:43p 05:46a | Set 09:49p 6%| |Thu 24| 06:56a 08:33p 13:37 | 09:41p 05:47a | Set 10:18p 12%| |Fri 25| 06:57a 08:31p 13:34 | 09:39p 05:49a | Set 10:46p 20%| |Sat 26| 06:58a 08:29p 13:31 | 09:37p 05:50a | Set 11:15p 28%| +------+-----------------------+----------------+-----------------------+ |Sun 27| 06:59a 08:27p 13:28 | 09:35p 05:52a | Set 11:46p 37%| |Mon 28| 07:00a 08:26p 13:25 | 09:33p 05:53a | Set 12:19a 47%| |Tue 29| 07:01a 08:24p 13:22 | 09:31p 05:54a |F Qtr Set 12:56a 56%| |Wed 30| 07:03a 08:22p 13:19 | 09:29p 05:56a | Set 01:38a 65%| |Thu 31| 07:04a 08:20p 13:16 | 09:27p 05:57a | Set 02:24a 74%| +-----------------------------------------------------------------------+ * Nautical Twilight ** Moonrise or moonset, whichever occurs between sunset and sunrise
