Archive
06/29/2018 – Ephemeris – Previewing July skies
Ephemeris for Friday, June 29th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:32, and it will rise tomorrow at 6:00. The Moon, 1 day past full, will rise at 10:38 this evening.
Lets preview July’s skies. The Sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 30 minutes Sunday to 14 hours 41 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the Sun at local noon, when the Sun is due south will decrease from 68 degrees today to 63 degrees at month’s end. The Sun will be a degree lower in the Straits area. Despite the warmth, the Earth will reach its greatest distance from the Sun on Friday the 6th. The planets visible this month in the evening are Venus, Jupiter, Saturn and later, Mars.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
July Evening Star Chart

Star Chart for July 2018 (11 p.m. EDT July 15, 2018). Created using my LookingUp program. Click on image to enlarge.
The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 4:30 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). 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 of 11 p.m. and 4:30 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. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog.
July Morning Star Chart

Star Chart for July 2018 mornings based on 4:30 a.m. July 15th. Created using my LookingUp program. Click on image to enlarge.
For a list of constellation names to go with the abbreviations click here.
Star chart annotations
- 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 and
- Continue with a spike to Spica.
- The Summer Triangle is in red.
- DAqR – Delta Aquariid meteor shower radiant
Twilight
Evening nautical twilight ends at 11:00 p.m. EDT on the 1st, decreasing to 10:28 p.m. EDT on the 31st.
Evening astronomical twilight ends at 12:03 a.m. EDT on the 1st, decreasing to 11:28 a.m. EDT on the 31st.
Morning astronomical twilight starts at 3:38 a.m. EDT on the 1st, and increasing to 4:28 a.m. EDT on the 31st.
Morning nautical twilight starts at 4:41 a.m. EDT on the 1st, and increasing to 5:17 a.m. EDT on the 31st.
NASA Calendar of Planetary Events
Date Time Event
Jul 01 Su Venus: 40.7° E
04 We 1:39 am Mercury-Beehive: 0.6° S
06 Fr 3:51 am Last Quarter
06 Fr 11:59 am Aphelion: 1.0167 AU
09 Mo 7:36 pm Venus-Regulus: 1° N
10 Tu 5:30 am Moon-Aldebaran: 1.1° S
12 Th 12:59 am Mercury Elongation: 26.4° E
12 Th 8:01 am Moon North Dec.: 20.8° N
12 Th 10:48 pm New Moon
12 Th 11:01 pm Partial Solar Eclipse (S Australia)
13 Fr 4:28 am Moon Perigee: 357400 km
13 Fr 10:50 pm Moon Ascending Node
14 Sa 6:04 pm Moon-Mercury: 2.2° S
15 Su 12:14 pm Moon-Regulus: 1.7° S
15 Su 11:31 pm Moon-Venus: 1.6° S
19 Th 3:52 pm First Quarter
20 Fr 7:57 pm Moon-Jupiter: 4.8° S
25 We 2:10 am Moon-Saturn: 2.2° S
25 We 4:55 pm Moon South Dec.: 20.8° S
27 Fr 1:31 am Mars Opposition
27 Fr 1:44 am Moon Apogee: 406200 km
27 Fr 4:21 pm Full Moon
27 Fr 4:22 pm Total Lunar Eclipse (S.America, Europe, Africa, Asia)
27 Fr 6:40 pm Moon Descending Node
28 Sa 4:50 pm Delta Aquarid Shower: ZHR = 20
31 Tu 3:51 am Mars closest to the Earth 57.59 mkm
Aug 01 We Venus: 45.1° E
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
July, 2018 Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun 1| 06:01a 09:32p 15:30 | 10:57p 04:35a | Rise 11:49p 88%|
|Mon 2| 06:01a 09:31p 15:30 | 10:56p 04:36a | Rise 12:19a 81%|
|Tue 3| 06:02a 09:31p 15:29 | 10:56p 04:37a | Rise 12:47a 72%|
|Wed 4| 06:02a 09:31p 15:28 | 10:56p 04:37a | Rise 01:13a 63%|
|Thu 5| 06:03a 09:30p 15:27 | 10:55p 04:38a | Rise 01:39a 53%|
|Fri 6| 06:04a 09:30p 15:26 | 10:54p 04:39a |L Qtr Rise 02:06a 43%|
|Sat 7| 06:04a 09:30p 15:25 | 10:54p 04:40a | Rise 02:36a 33%|
+------+-----------------------+----------------+-----------------------+
|Sun 8| 06:05a 09:29p 15:24 | 10:53p 04:41a | Rise 03:10a 23%|
|Mon 9| 06:06a 09:29p 15:22 | 10:52p 04:42a | Rise 03:50a 14%|
|Tue 10| 06:07a 09:28p 15:21 | 10:51p 04:43a | Rise 04:38a 7%|
|Wed 11| 06:08a 09:28p 15:20 | 10:51p 04:44a | Rise 05:36a 2%|
|Thu 12| 06:08a 09:27p 15:18 | 10:50p 04:46a |New Set 09:09p 0%|
|Fri 13| 06:09a 09:26p 15:17 | 10:49p 04:47a | Set 10:04p 1%|
|Sat 14| 06:10a 09:26p 15:15 | 10:48p 04:48a | Set 10:50p 5%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 06:11a 09:25p 15:14 | 10:47p 04:49a | Set 11:29p 12%|
|Mon 16| 06:12a 09:24p 15:12 | 10:46p 04:50a | Set 12:02a 21%|
|Tue 17| 06:13a 09:24p 15:10 | 10:44p 04:52a | Set 12:32a 31%|
|Wed 18| 06:14a 09:23p 15:08 | 10:43p 04:53a | Set 01:01a 41%|
|Thu 19| 06:15a 09:22p 15:07 | 10:42p 04:54a |F Qtr Set 01:29a 52%|
|Fri 20| 06:16a 09:21p 15:05 | 10:41p 04:56a | Set 01:57a 62%|
|Sat 21| 06:17a 09:20p 15:03 | 10:40p 04:57a | Set 02:28a 72%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 06:18a 09:19p 15:01 | 10:38p 04:58a | Set 03:03a 80%|
|Mon 23| 06:19a 09:18p 14:59 | 10:37p 05:00a | Set 03:41a 87%|
|Tue 24| 06:20a 09:17p 14:57 | 10:36p 05:01a | Set 04:25a 93%|
|Wed 25| 06:21a 09:16p 14:55 | 10:34p 05:03a | Set 05:13a 97%|
|Thu 26| 06:22a 09:15p 14:53 | 10:33p 05:04a | Set 06:06a 99%|
|Fri 27| 06:23a 09:14p 14:50 | 10:31p 05:05a |Full Rise 09:16p 100%|
|Sat 28| 06:24a 09:13p 14:48 | 10:30p 05:07a | Rise 09:51p 99%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 06:25a 09:12p 14:46 | 10:28p 05:08a | Rise 10:23p 96%|
|Mon 30| 06:26a 09:10p 14:44 | 10:27p 05:10a | Rise 10:51p 91%|
|Tue 31| 06:27a 09:09p 14:41 | 10:25p 05:11a | Rise 11:17p 85%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset
Ephemeris of Sky Events is created with my DOS version LookingUp program.