Bob Moler's Ephemeris Blog

This is Ephemeris for Tuesday, July 1st. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:32, and it will rise tomorrow at 6:01. The Moon, 1 day before first quarter, will set at 1:02 tomorrow morning.

Let’s 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 today 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 it 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 5:59 PM Thursday. That’s called aphelion where the Sun will be almost 94.5 million miles (152 million kilometers) away, making summer the longest season.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

July Evening Star Chart

The planets and stars are plotted for the 15th at 11 PM EDT in the evening and 4:30 AM on the 16th for the morning chart. These are the chart times. Note that Interlochen/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 of 11 PM and 4:30 AM are for the 15th & 16th respectively. For each week before these dates, add ½ hour (28 minutes if you’re picky). For each week after the 15th, subtract ½ hour, or 28 minutes. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than mid-month, check the Wednesday planet posts on this blog for weekly positions.

July 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.
• DAqR is the radiant of the South Delta Aquariid meteor shower (Peaks on the afternoon of the 27th)

Twilight Limits, Nautical and Astronomical

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

Jul  1  Tu            Venus: 43.4° W
     2  We   1:39 PM  Mercury-Beehive: 1.3° S
     2  We   3:30 PM  First Quarter
     3  Th   5:39 PM  Moon-Spica: 0.9° N
     3  Th   5:59 PM  Aphelion: 1.0166 AU
     3  Th  11:59 PM  Mercury Elongation: 25.9° East
     4  Fr  11:44 AM  Venus-Pleiades: 6.6° S
     4  Fr  10:28 PM  Moon Apogee: 404600 km
     7  Mo   1:37 PM  Moon-Antares: 0.4° N
     9  We   2:03 AM  Moon South Dec.: 28.4° S
    10  Th   4:37 PM  Full Moon
    13  Su   4:29 AM  Venus-Aldebaran: 3.1° N
    15  Tu   6:42 AM  Moon Ascending Node
    16  We   6:19 AM  Moon-Saturn: 3.9° S
    17  Th   8:38 PM  Last Quarter
    20  Su   6:27 AM  Moon-Pleiades: 0.8° S
    20  Su   9:52 AM  Moon Perigee: 368000 km
    22  Tu   5:43 AM  Moon North Dec.: 28.5° N
    23  We  12:20 AM  Moon-Jupiter: 5° S
    24  Th   3:11 PM  New Moon
    26  Sa   3:44 PM  Moon-Regulus: 1.4° S
    27  Su  11:53 PM  Delta Aquariid Meteor Shower: ZHR = 20
    28  Mo   4:30 AM  Moon Descending Node
    28  Mo   3:45 PM  Moon-Mars: 1.4° N
    31  Th   1:45 AM  Moon-Spica: 1.1° N
    31  Th   7:35 PM  Mercury Inferior Conjunction
Aug  1  Fr            Venus: 38° W

All event times are given for UTC-4:00 Eastern Daylight Saving Time thereafter.

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.

Note that the site is now kept up for archival purposes. Fred Espenak retired from NASA several years ago and has his own site, AstroPixels, which contain the same information: http://astropixels.com/almanac/almanac.html. However, it uses standard time all year.

Fred passed away a month ago, on June 1, 2025. RIP.

Sun and Moon Rising and Setting Events

LU              Ephemeris of Sky Events for Interlochen/TC
July 2025    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Tue  1| 06:01a  09:32p  15:30 | 10:57p  04:35a |      Set  01:02a   42%|
|Wed  2| 06:01a  09:31p  15:29 | 10:56p  04:36a |F Qtr Set  01:18a   52%|
|Thu  3| 06:02a  09:31p  15:29 | 10:56p  04:37a |      Set  01:36a   61%|
|Fri  4| 06:03a  09:31p  15:28 | 10:55p  04:38a |      Set  01:56a   70%|
|Sat  5| 06:03a  09:30p  15:27 | 10:55p  04:39a |      Set  02:20a   78%|
+------+-----------------------+----------------+-----------------------+
|Sun  6| 06:04a  09:30p  15:26 | 10:54p  04:40a |      Set  02:51a   86%|
|Mon  7| 06:05a  09:30p  15:24 | 10:53p  04:41a |      Set  03:30a   92%|
|Tue  8| 06:05a  09:29p  15:23 | 10:53p  04:42a |      Set  04:20a   96%|
|Wed  9| 06:06a  09:29p  15:22 | 10:52p  04:43a |      Set  05:21a   99%|
|Thu 10| 06:07a  09:28p  15:21 | 10:51p  04:44a |Full  Rise 09:58p  100%|
|Fri 11| 06:08a  09:28p  15:19 | 10:50p  04:45a |      Rise 10:32p   98%|
|Sat 12| 06:09a  09:27p  15:18 | 10:49p  04:46a |      Rise 10:59p   95%|
+------+-----------------------+----------------+-----------------------+
|Sun 13| 06:10a  09:26p  15:16 | 10:48p  04:47a |      Rise 11:22p   89%|
|Mon 14| 06:10a  09:26p  15:15 | 10:47p  04:48a |      Rise 11:42p   82%|
|Tue 15| 06:11a  09:25p  15:13 | 10:46p  04:50a |      Rise 12:01a   72%|
|Wed 16| 06:12a  09:24p  15:11 | 10:45p  04:51a |      Rise 12:20a   62%|
|Thu 17| 06:13a  09:23p  15:10 | 10:44p  04:52a |L Qtr Rise 12:42a   50%|
|Fri 18| 06:14a  09:23p  15:08 | 10:43p  04:53a |      Rise 01:07a   39%|
|Sat 19| 06:15a  09:22p  15:06 | 10:42p  04:55a |      Rise 01:40a   28%|
+------+-----------------------+----------------+-----------------------+
|Sun 20| 06:16a  09:21p  15:04 | 10:40p  04:56a |      Rise 02:23a   18%|
|Mon 21| 06:17a  09:20p  15:02 | 10:39p  04:57a |      Rise 03:18a   10%|
|Tue 22| 06:18a  09:19p  15:00 | 10:38p  04:59a |      Rise 04:27a    4%|
|Wed 23| 06:19a  09:18p  14:58 | 10:36p  05:00a |      Rise 05:43a    1%|
|Thu 24| 06:20a  09:17p  14:56 | 10:35p  05:02a |New   Set  09:41p    0%|
|Fri 25| 06:21a  09:16p  14:54 | 10:34p  05:03a |      Set  10:09p    2%|
|Sat 26| 06:22a  09:15p  14:52 | 10:32p  05:04a |      Set  10:31p    6%|
+------+-----------------------+----------------+-----------------------+
|Sun 27| 06:23a  09:14p  14:50 | 10:31p  05:06a |      Set  10:49p   11%|
|Mon 28| 06:24a  09:12p  14:48 | 10:29p  05:07a |      Set  11:06p   18%|
|Tue 29| 06:26a  09:11p  14:45 | 10:28p  05:09a |      Set  11:23p   27%|
|Wed 30| 06:27a  09:10p  14:43 | 10:26p  05:10a |      Set  11:40p   36%|
|Thu 31| 06:28a  09:09p  14:41 | 10:24p  05:12a |      Set  11:59p   45%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

Generated using my LookingUp for DOS app.