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Ephemeris: 05/30/2025 – Ending orbit 50, looking ahead to the 1st month of orbit 51
This is Bob Moler with Ephemeris for Friday, May 30th, the last program of Ephemeris’ 50th orbit of the Sun. Today the Sun will be up for 15 hours and 18 minutes, setting at 9:19, and it will rise tomorrow at 6:00. The Moon, 3 days before first quarter, will set at 1:17 tomorrow morning.
Let’s take a look at June skies. There will be a lot of sunshine this month. The daylight hours will increase a bit from 15 hours and 21 minutes today to 15 hours and 34 minutes on the 21st, retreating back to 15 hours 31 minutes at month’s end. At this time of the year the sunset times for Ludington, Interlochen, Petoskey and Mackinaw City are very nearly the same. However, the sunrise times are at their most divergent. With Ludington’s sunrise being 14 minutes later than Mackinaw City’s. The altitude of the Sun above the southern horizon at local noon (1:44 pm in Interlochen) on the solstice, June 20th will be 68 and three-quarters degrees. Summer will start at 10:42 PM that night.
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
June Evening Star Chart
The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 4 a.m. 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 p.m. and 4 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, or 28 minutes. 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 for weekly positions.
June 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,
Twilight Limits, Nautical and Astronomical
| EDT | |||||||
| Morning | Twilight | Evening | Twilight | Dark | Night | Moon | |
| Date | Astro. | Nautical | Nautical | Astro. | Start | End | Illum. |
| 2025-06-01 | 3h39m | 4h38m | 22h47m | 23h46m | 1h45m | 3h39m | 0.41 |
| 2025-06-02 | 3h38m | 4h37m | 22h48m | 23h48m | 2h07m | 3h38m | 0.51 |
| 2025-06-03 | 3h37m | 4h37m | 22h49m | 23h49m | 2h26m | 3h37m | 0.60 |
| 2025-06-04 | 3h36m | 4h36m | 22h50m | 23h51m | 2h42m | 3h36m | 0.70 |
| 2025-06-05 | 3h35m | 4h35m | 22h51m | 23h52m | 2h58m | 3h35m | 0.78 |
| 2025-06-06 | 3h34m | 4h35m | 22h52m | 23h53m | 3h14m | 3h34m | 0.85 |
| 2025-06-07 | 3h33m | 4h34m | 22h53m | 23h55m | 3h33m | 3h33m | 0.91 |
| 2025-06-08 | 3h32m | 4h34m | 22h54m | 23h56m | – | – | 0.96 |
| 2025-06-09 | 3h31m | 4h33m | 22h55m | 23h57m | – | – | 0.99 |
| 2025-06-10 | 3h30m | 4h33m | 22h55m | 23h58m | – | – | 1.00 |
| 2025-06-11 | 3h30m | 4h33m | 22h56m | 23h59m | – | – | 0.99 |
| 2025-06-12 | 3h29m | 4h32m | 22h57m | 0h00m | – | – | 0.96 |
| 2025-06-13 | 3h29m | 4h32m | 22h58m | 0h01m | – | – | 0.92 |
| 2025-06-14 | 3h28m | 4h32m | 22h58m | 0h02m | – | – | 0.85 |
| 2025-06-15 | 3h28m | 4h32m | 22h59m | 0h03m | 0h03m | 0h30m | 0.77 |
| 2025-06-16 | 3h28m | 4h32m | 22h59m | 0h03m | 0h03m | 0h55m | 0.68 |
| 2025-06-17 | 3h28m | 4h32m | 23h00m | 0h04m | 0h04m | 1h17m | 0.57 |
| 2025-06-18 | 3h28m | 4h32m | 23h00m | 0h04m | 0h04m | 1h36m | 0.46 |
| 2025-06-19 | 3h28m | 4h32m | 23h00m | 0h05m | 0h05m | 1h56m | 0.34 |
| 2025-06-20 | 3h28m | 4h32m | 23h00m | 0h05m | 0h05m | 2h16m | 0.24 |
| 2025-06-21 | 3h28m | 4h32m | 23h01m | 0h05m | 0h05m | 2h39m | 0.14 |
| 2025-06-22 | 3h28m | 4h33m | 23h01m | 0h05m | 0h05m | 3h07m | 0.07 |
| 2025-06-23 | 3h29m | 4h33m | 23h01m | 0h05m | 0h05m | 3h29m | 0.02 |
| 2025-06-24 | 3h29m | 4h33m | 23h01m | 0h05m | 0h05m | 3h29m | 0.00 |
| 2025-06-25 | 3h30m | 4h34m | 23h01m | 0h05m | 0h05m | 3h30m | 0.01 |
| 2025-06-26 | 3h30m | 4h34m | 23h01m | 0h05m | 0h05m | 3h30m | 0.04 |
| 2025-06-27 | 3h31m | 4h35m | 23h01m | 0h05m | 0h05m | 3h31m | 0.10 |
| 2025-06-28 | 3h32m | 4h35m | 23h01m | 0h04m | 0h04m | 3h32m | 0.17 |
| 2025-06-29 | 3h33m | 4h36m | 23h00m | 0h04m | 0h09m | 3h33m | 0.26 |
| 2025-06-30 | 3h34m | 4h37m | 23h00m | 0h03m | 0h29m | 3h34m | 0.35 |
The twilight calendar was generated using Cartes du Ciel (Sky Charts), with some modifications. 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
Jun 1 Su Venus: 45.9° W
1 Su 5:49 AM Moon-Mars: 1.5° S
1 Su 9:30 PM Moon-Regulus: 1.9° S
2 Mo 11:41 PM First Quarter
3 Tu 9:33 PM Moon Descending Node
6 Fr 10:15 AM Moon-Spica: 0.6° N
7 Sa 6:42 AM Moon Apogee: 405600 km
10 Tu 6:25 AM Moon-Antares: 0.3° N
11 We 3:44 AM Full Moon
11 We 7:54 PM Moon South Dec.: 28.4° S
16 Mo 10:05 PM Mars-Regulus: 0.7° N
18 We 5:41 AM Moon Ascending Node
18 We 3:19 PM Last Quarter
18 We 11:47 PM Moon-Saturn: 3.4° S
20 Fr 10:42 PM Summer Solstice
21 Sa 3:51 PM Mercury-Pollux: 5° S
22 Su 10:59 PM Moon-Pleiades: 0.6° S
23 Mo 12:43 AM Moon Perigee: 363200 km
24 Tu 11:06 AM Jupiter Conjunction
24 Tu 9:43 PM Moon North Dec.: 28.4° N
25 We 6:31 AM New Moon
27 Fr 2:02 AM Moon-Mercury: 2.9° S
27 Fr 1:42 PM Moon-Beehive: 2.1° S
29 Su 6:26 AM Moon-Regulus: 1.6° S
29 Su 9:05 PM Moon-Mars: 0.2° S
30 Mo 11:46 PM Moon Descending Node
Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html.
Sun and Moon Rising and Setting Events
LU Ephemeris of Sky Events for Interlochen/Traverse City, MI
June, 2025 Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun 1| 06:00a 09:21p 15:21 | 10:45p 04:37a | Set 02:07a 38%|
|Mon 2| 05:59a 09:22p 15:22 | 10:46p 04:36a |F Qtr Set 02:25a 48%|
|Tue 3| 05:59a 09:23p 15:23 | 10:47p 04:35a | Set 02:41a 58%|
|Wed 4| 05:58a 09:23p 15:25 | 10:48p 04:34a | Set 02:57a 68%|
|Thu 5| 05:58a 09:24p 15:26 | 10:49p 04:34a | Set 03:14a 76%|
|Fri 6| 05:58a 09:25p 15:27 | 10:50p 04:33a | Set 03:32a 84%|
|Sat 7| 05:57a 09:26p 15:28 | 10:51p 04:33a | Set 03:53a 90%|
+------+-----------------------+----------------+-----------------------+
|Sun 8| 05:57a 09:26p 15:29 | 10:51p 04:32a | Set 04:20a 95%|
|Mon 9| 05:57a 09:27p 15:30 | 10:52p 04:32a | Set 04:53a 98%|
|Tue 10| 05:57a 09:27p 15:30 | 10:53p 04:31a | Set 05:36a 100%|
|Wed 11| 05:56a 09:28p 15:31 | 10:54p 04:31a |Full Rise 10:31p 99%|
|Thu 12| 05:56a 09:29p 15:32 | 10:54p 04:31a | Rise 11:20p 97%|
|Fri 13| 05:56a 09:29p 15:32 | 10:55p 04:30a | Rise 11:59p 93%|
|Sat 14| 05:56a 09:29p 15:33 | 10:55p 04:30a | Rise 12:30a 87%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 05:56a 09:30p 15:33 | 10:56p 04:30a | Rise 12:55a 79%|
|Mon 16| 05:56a 09:30p 15:34 | 10:56p 04:30a | Rise 01:17a 69%|
|Tue 17| 05:56a 09:31p 15:34 | 10:57p 04:30a | Rise 01:36a 59%|
|Wed 18| 05:56a 09:31p 15:34 | 10:57p 04:30a |L Qtr Rise 01:55a 48%|
|Thu 19| 05:56a 09:31p 15:34 | 10:58p 04:30a | Rise 02:15a 37%|
|Fri 20| 05:57a 09:31p 15:34 | 10:58p 04:30a | Rise 02:38a 26%|
|Sat 21| 05:57a 09:32p 15:34 | 10:58p 04:30a | Rise 03:07a 16%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 05:57a 09:32p 15:34 | 10:58p 04:31a | Rise 03:44a 9%|
|Mon 23| 05:57a 09:32p 15:34 | 10:58p 04:31a | Rise 04:33a 3%|
|Tue 24| 05:58a 09:32p 15:34 | 10:58p 04:31a | Rise 05:36a 0%|
|Wed 25| 05:58a 09:32p 15:34 | 10:58p 04:32a |New Set 10:28p 1%|
|Thu 26| 05:58a 09:32p 15:33 | 10:58p 04:32a | Set 11:12p 3%|
|Fri 27| 05:59a 09:32p 15:33 | 10:58p 04:33a | Set 11:44p 8%|
|Sat 28| 05:59a 09:32p 15:32 | 10:58p 04:33a | Set 12:08a 15%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 06:00a 09:32p 15:32 | 10:57p 04:34a | Set 12:28a 24%|
|Mon 30| 06:00a 09:32p 15:31 | 10:57p 04:35a | Set 12:46a 33%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise
Generated using my LookingUp for DOS app.
Ephemeris: 05/29/2025 – Finding the celestial dragon
This is Ephemeris for Thursday, May 29th. Today the Sun will be up for 15 hours and 17 minutes, setting at 9:19, and it will rise tomorrow at 6:01. The Moon, 3 days past new, will set at 12:40 tomorrow morning.
High in the northern sky at 11 p.m. lies the twisted constellation of Draco the dragon. This dragon is more like the snakelike dragon of the Chinese New Year parades than the dinosaur-like dragon of European legend. I find it better to start at the tail of Draco, to trace him out in the stars. Draco’s tail ends between the Big and Little Dippers high in the north-northwest. The Dragon is seen in a line of stars that extends parallel to the handle of the Big Dipper before curving around the bowl of the Little Dipper then bends back down to the level of Polaris in the north-northeast before turning toward the east. The head of Draco is an odd box of stars near the bright star Vega, in the east. Though not made up of very bright stars, Draco has an easy shape to trace.
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
Ephemeris: 05/28/2025 – Our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, May 28th. Today the Sun will be up for 15 hours and 15 minutes, setting at 9:18, and it will rise tomorrow at 6:01. The Moon, 2 days past new, will set at 11:50 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 10 PM this evening two naked eye planets will be out. Jupiter, is now low in the west-northwestern sky Underneath the waxing crescent Moon. The fading Mars, with its distinctive reddish hue, is in the west-southwest, at that time. It’s slowly approaching the bright star Regulus in Leo the lion, which it will pass on June 16th. By 5 AM Venus will be seen very low in the east, as the Morning Star, with Saturn to the right and a bit above it. Venus will require a low eastern horizon then. But it will rise and be visible until close to 5:45. For those with telescopes, Saturn’s rings are now opening up again, and will for the next 7 years.
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
Ephemeris: 05/27/2025 – The many faces of the Big Dipper
This is Ephemeris for Tuesday, May 27th. Today the Sun will be up for 15 hours and 13 minutes, setting at 9:17, and it will rise tomorrow at 6:02. The Moon, 1 day past new, will set at 10:44 this evening.
The Big Dipper is overhead, actually north of overhead this evening when it gets dark for us in Michigan, it’s seven stars shining brightly. The Big Dipper is not an actual constellation, recognized internationally. It’s part, the hind part, of Ursa Major, the great bear. The Big Dipper is an asterism or informal constellation. It is a distinctly North American constellation. For fugitive slaves, fleeing the southern states in the days before the Civil War, the Drinking Gourd, as they called it, showed the direction north to freedom. In England the dipper stars become the Plough (plow), or Charles’ Wain (Charlemagne’s Wagon). In France, known for culinary delights it is the saucepan, or the cleaver. Many cultures saw what was familiar to them in these seven bright stars.
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
Ephemeris: 05/26/2025 – About globular star clusters
This is Ephemeris for Memorial Day, Monday, May 26th. Today the Sun will be up for 15 hours and 12 minutes, setting at 9:16, and it will rise tomorrow at 6:03. The Moon is new today, and won’t be visible.
The constellation Hercules, out in the evening sky now, contains the brightest globular star cluster in the northern sky. A globular star cluster, about 25 thousand light years away. It’s an ancient assemblage of hundreds of thousands to millions of stars in a big ball. About 150 of these star clusters, that we know of, exist in the Milky Way. They form a spherical distribution around the Milky Way concentrated towards the center. The ages of these clusters runs to over 10 billion years. It is thought that they formed first out of the gas of the Milky Way and so did not participate in the collapse of the gas into the disk of the Milky Way we know today from which later stars were formed. We see them in other galaxies.
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
Ephemeris: 05/23/2025 – M13, The Great Hercules Star Cluster
This is Ephemeris for Friday, May 23rd. Today the Sun will be up for 15 hours and 6 minutes, setting at 9:13, and it will rise tomorrow at 6:05. The Moon, halfway from last quarter to new, will rise at 4:13 tomorrow morning.
The constellation Hercules the hero can be found between the bright stars Vega which is fairly low in the east northeast and Arcturus high in the southeast. It’s about 1/3 of the way from Vega to Arcturus. His most distinctive feature is the keystone a box of four stars wider at the top than the bottom. Along the western edge of the keystone can be seen, sometimes with the naked eye, but better with binoculars as a small spot about 1/3 of the way down from the top star to the bottom star. It looks like a fuzzy spot. In telescopes smaller than 8 inch diameter, at least with my eyes, it stays fuzzy, but in larger telescopes it begins to crystallize out into a myriad of stars. It is the Great Hercules Globular Star Cluster. Number 13 on late 18th century astronomer Charles Messier’s catalog of fuzzy objects that weren’t the comets he was looking for. We know it as Messier 13, or M13.
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
Ephemeris: 05/22/2025 – Finding Hercules among the spring stars
This is Bob Moler with Ephemeris for Thursday, May 22nd. Today the Sun will be up for 15 hours and 5 minutes, setting at 9:12, and it will rise tomorrow at 6:06. The Moon, 2 days past last quarter, will rise at 3:51 tomorrow morning.
In the eastern sky at 11 PM about a third of the way along the line from the bright star Vega in the east northeast and Arcturus high in the southeast is the constellation of Hercules the hero. It’s kind of hard to spot, although it’s one distinctive feature is the box of four stars called the Keystone of Hercules which means it’s wider at the top than at the bottom. That is his body. He’s upside down in the sky according to how they draw the picture of Hercules. Most of his stars are reasonably dim. This is the great hero of Greek myth. While in the winter sky the bright and splashy constellation of Orion the hunter, was kind of a hard luck hero, with no real accomplishments. Hercules has an astronomical jewel that I’ll talk about tomorrow.
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
Ephemeris: 05/21/2025 – Checking where the naked-eye planets are
This is Bob Moler with Ephemeris for Wednesday, May 21st. Today the Sun will be up for 15 hours and 3 minutes, setting at 9:11, and it will rise tomorrow at 6:07. The Moon, 1 day past last quarter, will rise at 3:32 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 10 PM this evening two naked eye planets will be out. Jupiter, is now low in the west-northwestern sky. The rapidly fading Mars, with its distinctive reddish hue, is in the west-southwest, at that time. Once it’s darker binoculars can be used to spot the Beehive Star Cluster to its lower right. By 5 AM Venus will be seen very low in the east, as the Morning Star, with Saturn and the waning crescent Moon in an upward line to the right and a bit above it. Venus will require a low eastern horizon then. But it will rise and be visible until close to 5:45 or later. For those with telescopes, Saturn’s rings are now opening up again, and will for the next 7 years.
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
Ephemeris: 05/20/2025 – Corona Borealis, Ariadne’s Crown
This is Ephemeris for Tuesday, May 20th. Today the Sun will be up for 15 hours and 1 minute, setting at 9:10, and it will rise tomorrow at 6:08. The Moon, at last quarter today, will rise at 3:12 tomorrow morning.
There are two bright stars in the eastern part of the sky. High in the southeast at 11 PM is Arcturus, and in the east northeast, lower down is the star Vega. A third of the way between Arcturus and Vega is a small arc of stars called Corona Borealis, the northern crown. It is a small constellation. The brightest star in it is called Alphecca. According to Greek mythology it is the crown given to Princess Ariadne, daughter of King Minos of Crete. Of interest in the next year or so is a possibility of a nova or bright star appearing just south of that arc of stars for about a week. It is a recurrent nova, which explodes about every 80 years. The last time was in 1946, so the next time would be within the next year or so. And astronomers are breathlessly waiting for that to happen.
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
Ephemeris: 05/19/2025 – Finding Libra the scales
This is Ephemeris for Monday, May 19th. Today the Sun will be up for 14 hours and 59 minutes, setting at 9:09, and it will rise tomorrow at 6:09. The Moon, 1 day before last quarter, will rise at 2:51 tomorrow morning.
Libra the scales or balance is a dim constellation which is seen low in the southeast in the evening now. It is one of the constellations of the Zodiac. The term Zodiac means circle of animals, so Libra doesn’t exactly fit. The ancient Babylonians recognized it. Back then it may have represented the equality of day and night because the Sun would have been at the autumnal equinox in Libra at that time. The early Greeks, and possibly the Arabs, did not see Libra as being separate from the constellation of Scorpius the scorpion, which is rising to its lower left. Its two brightest stars have Arabic names meaning north claw and south claw. Scorpions have claws, and last I’ve checked, balances do not.
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
A bit of trivia: At 14 letters Zubeneschamali is the longest star name.
In a previous post I noted that Libra was associated with Virgo which also represents Astraea the goddess of Justice, with Libra, being her Scales of Justice.
Bob Moler's Ephemeris Blog 