Archive
Ephemeris: 10/01/2026 – Previewing October skies
This is Ephemeris for Thursday, October 1st. Today the Sun will be up for 11 hours and 42 minutes, setting at 7:23, and it will rise tomorrow at 7:42. The Moon, 2 days before last quarter, will rise at 10:06 this evening.
Let’s look at the skies for the month of October. The Sun will still be moving south rapidly. Daylight hours in the Interlochen/Traverse City area and will drop from 11 hours and 42 minutes today to 10 hours, 13 minutes at months end. The altitude of the sun above the southern horizon at local noon will be 42 degrees today in the Interlochen area and will descend to 31 degrees on Halloween. Venus will pass the Sun, moving from the evening sky to the morning sky on the 23rd. Venus has not been too noticeable in the evening for the last month, but by early November it will seem to suddenly appear in the morning sky. It can be mistaken as a UFO, especially with its tiny Cheshire Cat crescent smile in binoculars or a small telescope.
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
October Evening Star Chart
The planets and stars are plotted for the 15th at 10 p.m. EDT in the evening and 6 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.
October Morning Star Chart
Twilight Limits, Nautical and Astronomical
| EDT | |||||||
| Morning | Twilight | Evening | Twilight | Dark | Night | Moon | |
| Date | Astro. | Nautical | Nautical | Astro. | Start | End | Illum. |
| 2026-10-01 | 6h05m | 6h39m | 20h29m | 21h04m | 21h04m | 22h07m | 66% |
| 2026-10-02 | 6h06m | 6h40m | 20h27m | 21h02m | 21h02m | 23h11m | 54% |
| 2026-10-03 | 6h08m | 6h42m | 20h26m | 21h00m | 21h00m | – | 43% |
| 2026-10-04 | 6h09m | 6h43m | 20h24m | 20h58m | 20h58m | 0h25m | 32% |
| 2026-10-05 | 6h10m | 6h44m | 20h22m | 20h56m | 20h56m | 1h44m | 22% |
| 2026-10-06 | 6h11m | 6h45m | 20h20m | 20h54m | 20h54m | 3h03m | 13% |
| 2026-10-07 | 6h13m | 6h47m | 20h18m | 20h52m | 20h52m | 4h19m | 7% |
| 2026-10-08 | 6h14m | 6h48m | 20h17m | 20h50m | 20h50m | 5h32m | 2% |
| 2026-10-09 | 6h15m | 6h49m | 20h15m | 20h49m | 20h49m | 6h15m | 0% |
| 2026-10-10 | 6h16m | 6h50m | 20h13m | 20h47m | 20h47m | 6h16m | 0% |
| 2026-10-11 | 6h18m | 6h51m | 20h11m | 20h45m | 20h45m | 6h18m | 3% |
| 2026-10-12 | 6h19m | 6h53m | 20h10m | 20h43m | 20h43m | 6h19m | 7% |
| 2026-10-13 | 6h20m | 6h54m | 20h08m | 20h42m | 20h42m | 6h20m | 12% |
| 2026-10-14 | 6h21m | 6h55m | 20h06m | 20h40m | 20h45m | 6h21m | 19% |
| 2026-10-15 | 6h23m | 6h56m | 20h05m | 20h38m | 21h32m | 6h23m | 28% |
| 2026-10-16 | 6h24m | 6h58m | 20h03m | 20h37m | 22h27m | 6h24m | 36% |
| 2026-10-17 | 6h25m | 6h59m | 20h01m | 20h35m | 23h29m | 6h25m | 46% |
| 2026-10-18 | 6h26m | 7h00m | 19h56m | 20h33m | – | 6h26m | 55% |
| 2026-10-19 | 6h28m | 7h01m | 19h54m | 20h32m | 0h34m | 6h28m | 65% |
| 2026-10-20 | 6h29m | 7h02m | 19h53m | 20h30m | 1h41m | 6h29m | 74% |
| 2026-10-21 | 6h30m | 7h04m | 19h51m | 20h29m | 2h49m | 6h30m | 82% |
| 2026-10-22 | 6h31m | 7h05m | 19h49m | 20h27m | 3h58m | 6h31m | 89% |
| 2026-10-23 | 6h32m | 7h06m | 19h48m | 20h26m | 5h08m | 6h32m | 95% |
| 2026-10-24 | 6h34m | 7h07m | 19h47m | 20h24m | 6h21m | 6h34m | 99% |
| 2026-10-25 | 6h35m | 7h09m | 19h45m | 20h23m | – | – | 100% |
| 2026-10-26 | 6h36m | 7h10m | 19h44m | 20h21m | – | – | 99% |
| 2026-10-27 | 6h37m | 7h11m | 19h42m | 20h20m | – | – | 94% |
| 2026-10-28 | 6h38m | 7h12m | 19h41m | 20h19m | – | – | 88% |
| 2026-10-29 | 6h40m | 7h13m | 19h39m | 20h17m | 20h17m | 21h02m | 79% |
| 2026-10-30 | 6h41m | 7h15m | 19h38m | 20h16m | 20h16m | 22h15m | 69% |
| 2026-10-31 | 6h42m | 7h16m | 19h37m | 20h15m | 20h15m | 23h34m | 58% |
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
Oct 1 Th Venus: 30.8° E
1 Th 4:41 PM Moon Perigee: 369300 km
2 Fr 7:35 AM Moon North Dec.: 28° N
3 Sa 9:25 AM Last Quarter
4 Su 7:52 AM Saturn Opposition
5 Mo 1:30 AM Moon-Mars: 1.2° S
5 Mo 7:06 AM Moon-Beehive: 0.4° S
6 Tu 6:18 AM Moon-Jupiter: 0.2° S
6 Tu 9:19 PM Moon Descending Node
6 Tu 10:57 PM Moon-Regulus: 0.6° N
6 Tu 11:59 PM Mercury-Venus: 5° N
10 Sa 11:50 AM New Moon
10 Sa 11:55 AM Mars-Beehive: 0.4° S
11 Su 10:30 PM Moon-Venus: 3.3° S
12 Mo 5:59 AM Mercury Elongation: 25.2° E
(Poor for N. Hemisphere observers
12 Mo 4:08 PM Moon-Mercury: 2.3° N
14 We 4:25 PM Moon-Antares: 0.5° N
15 Th 10:45 PM Moon South Dec.: 27.9° S
16 Fr 6:56 PM Moon Apogee: 404600 km
18 Su 12:13 PM First Quarter
21 We 4:53 AM Moon Ascending Node
21 We 2:16 PM Orionid Shower: ZHR = 20
23 Fr 11:29 PM Venus Inferior Conjunction
25 Su 11:12 PM Full Moon
27 Tu 8:11 PM Moon-Pleiades: 1° S
28 We 1:01 PM Moon Perigee: 364400 km
29 Th 12:40 PM Moon North Dec.: 27.8° N
Nov 1 Su Venus: 13.9° W
Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC), with modifications by the author.
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 October, 2026 Local time zone: EDT +-----------------------------------------------------------------------+ | DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM | | | RISE SET HOURS | END START |PHASE SET** TIME FRACTN| +=======================================================================+ |Thu 1| 07:40a 07:23p 11:42 | 08:26p 06:37a | Rise 10:06p 68%| |Fri 2| 07:42a 07:21p 11:39 | 08:24p 06:39a | Rise 11:11p 56%| |Sat 3| 07:43a 07:19p 11:36 | 08:22p 06:40a |L Qtr Rise 12:25a 45%| +------+-----------------------+----------------+-----------------------+ |Sun 4| 07:44a 07:17p 11:33 | 08:20p 06:41a | Rise 01:44a 34%| |Mon 5| 07:45a 07:15p 11:30 | 08:18p 06:42a | Rise 03:02a 24%| |Tue 6| 07:47a 07:13p 11:26 | 08:16p 06:43a | Rise 04:18a 15%| |Wed 7| 07:48a 07:12p 11:23 | 08:15p 06:45a | Rise 05:32a 8%| |Thu 8| 07:49a 07:10p 11:20 | 08:13p 06:46a | Rise 06:44a 3%| |Fri 9| 07:50a 07:08p 11:17 | 08:11p 06:47a | Rise 07:55a 1%| |Sat 10| 07:52a 07:06p 11:14 | 08:09p 06:48a |New Set 06:47p 0%| +------+-----------------------+----------------+-----------------------+ |Sun 11| 07:53a 07:04p 11:11 | 08:08p 06:50a | Set 07:09p 2%| |Mon 12| 07:54a 07:03p 11:08 | 08:06p 06:51a | Set 07:34p 6%| |Tue 13| 07:55a 07:01p 11:05 | 08:04p 06:52a | Set 08:06p 11%| |Wed 14| 07:57a 06:59p 11:02 | 08:02p 06:53a | Set 08:44p 18%| |Thu 15| 07:58a 06:58p 10:59 | 08:01p 06:55a | Set 09:31p 26%| |Fri 16| 07:59a 06:56p 10:56 | 07:59p 06:56a | Set 10:26p 34%| |Sat 17| 08:00a 06:54p 10:53 | 07:57p 06:57a | Set 11:28p 44%| +------+-----------------------+----------------+-----------------------+ |Sun 18| 08:02a 06:52p 10:50 | 07:56p 06:58a |F Qtr Set 12:33a 53%| |Mon 19| 08:03a 06:51p 10:47 | 07:54p 06:59a | Set 01:40a 63%| |Tue 20| 08:04a 06:49p 10:44 | 07:53p 07:01a | Set 02:48a 72%| |Wed 21| 08:06a 06:47p 10:41 | 07:51p 07:02a | Set 03:57a 80%| |Thu 22| 08:07a 06:46p 10:38 | 07:50p 07:03a | Set 05:07a 88%| |Fri 23| 08:08a 06:44p 10:35 | 07:48p 07:04a | Set 06:20a 94%| |Sat 24| 08:10a 06:43p 10:33 | 07:47p 07:06a | Set 07:36a 98%| +------+-----------------------+----------------+-----------------------+ |Sun 25| 08:11a 06:41p 10:30 | 07:45p 07:07a | Set 08:56a 100%| |Mon 26| 08:12a 06:40p 10:27 | 07:44p 07:08a |Full Rise 06:34p 99%| |Tue 27| 08:14a 06:38p 10:24 | 07:42p 07:09a | Rise 07:11p 95%| |Wed 28| 08:15a 06:37p 10:21 | 07:41p 07:10a | Rise 08:00p 89%| |Thu 29| 08:16a 06:35p 10:18 | 07:40p 07:12a | Rise 09:02p 81%| |Fri 30| 08:18a 06:34p 10:15 | 07:38p 07:13a | Rise 10:15p 71%| |Sat 31| 08:19a 06:32p 10:13 | 07:37p 07:14a | Rise 11:34p 60%| +-----------------------------------------------------------------------+ * Nautical Twilight ** Moonrise or moonset, whichever occurs between sunset and sunrise
Generated using my LookingUp for DOS app.
Ephemeris: 09/30/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, September 30th. Today the Sun will be up for 11 hours and 45 minutes, setting at 7:25, and it will rise tomorrow at 7:40. The Moon, 3 days before last quarter, will rise at 9:14 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus, now is too close to the horizon at sunset to easily spot. At sunset Venus will be only 4º above the horizon at sunset and will set at 7:52 PM. We will await its dramatic reappearance in the morning sky by early November. Saturn will be in the eastern sky as it gets dark. It is the brightest starlike object low in that direction. It will be below the four stars that make large distinctive pattern, that marks the body of Pegasus the flying horse, called the Great Square. At 6 AM, Jupiter and Mars will in the east. Jupiter is brightest and while red Mars will be above and just below and nearly in line with Castor and Pollux of Gemini.
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: Finding Andromeda and the great galaxy within
This is Ephemeris for Tuesday, September 29th. Today the Sun will be up for 11 hours and 48 minutes, setting at 7:26, and it will rise tomorrow at 7:39. The Moon, 3 days past full, will rise at 8:35 this evening.
For at least the last thousand or so years a fuzzy spot in the constellation of Andromeda has been known. It was known as the Great Andromeda Nebula until a little over 100 years ago. Nebula means cloud, and it belonged to the Milky Way. At that time it was finally recognized as another Milky Way just like ours. So the word to call it was galaxy, a word that’s related to milk. It looks to be among the stars of Andromeda, but it’s far beyond the stars that we make the constellation of Andromeda. Current estimates place it at about two and a half million light years away, well beyond the stars that we see in Andromeda that range to only a few thousand light years distance. It could collide with our galaxy in about 4 billion years or so.
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: 09/28/2026 – What happens to the Earth during Autumn
This is Ephemeris for Monday, September 28th. Today the Sun will be up for 11 hours and 51 minutes, setting at 7:28, and it will rise tomorrow at 7:38. The Moon, 2 days past full, will rise at 8:04 this evening.
Autumn is a season of change. The Sun, at noon each day, will not rise as high as the previous day. Sunrises will occur progressively later each day, while the Sun sets progressively earlier. This is not occuring by the earth moving away from the sun giving us colder temporatures. In fact throughout autumn we’re moving slowly closer to the Sun. But the entire yearly range in the sun’s distance change is only 3 million miles out of 93 million. The reason for the change of season is the tilt of the axis of the Earth to its orbital plane around the sun. The axis of the Earth points in a single direction, currently towards the star Polaris, so as the Earth moves around the Sun the Earth’s axis appears to change its orientation with the Sun.
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: 09/25/2026 – Our Harvest Moon marks the Chinese Mid-Autumn Festival
This is Ephemeris for Friday, September 25th. Today the Sun will be up for 12 hours and 0 minutes, setting at 7:34, and it will rise tomorrow at 7:34. The Moon, 1 day before full, will set at 7:29 tomorrow morning.
Tomorrow the Moon will be full. And since it’s only four days past the autumnal equinox, this makes it the Harvest Moon. This full moon also marks the Chinese Mid-Autumn Festival to honor the Moon and the story of Chang’e a mortal woman to took an elixir and flew off to the Moon and became a goddess. Another story revolves around the Jade Rabbit pounding Medicine. Beside the face one can see in the dark maria on the moon, we call the Man in the Moon, the Chinese saw the figure of a rabbit seen on the face of the Moon. He is a companion to Chang’e, and has a mortar and pestal with him. He pounds out the medicine that makes the inhabitants of the sky immortal. The Chinese lunar probes are named Chang’e, their rovers: Yutu, the Jade Rabbit.
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: 09/24/2026 – The Harvest Moon Effect
This is Ephemeris for Thursday, September 24th. Today the Sun will be up for 12 hours and 3 minutes, setting at 7:36, and it will rise tomorrow at 7:33. The Moon, 2 days before full, will set at 6:18 tomorrow morning.
The full, or nearly full moon, just rising, looks like a large orange pumpkin. The color, like the red of the sunset is caused by the scattering out of blue light by the atmosphere. It can happen at any full moon, not just the Harvest Moon, which will occur on Saturday. What the Moon around the Harvest Moon does do is rise only a little later each evening. This helped the farmers in earlier times effectively extend twilight to bring in the crops. On average the moon rises or sets 50 minutes later each night. However when the Moon is in the part of the sky where it is moving northward as well as eastward, then it rises only a little later each night. Tomorrow’s Moon will rise only 19 minutes later than it will this evening.
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: 09/23/2026 – Where did Venus go?
This is Ephemeris for Wednesday, September 23rd. Today the Sun will be up for 12 hours and 6 minutes, setting at 7:38, and it will rise tomorrow at 7:32. The Moon, 3 days before full, will set at 5:08 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus, now is too close to the horizon at sunset to easily spot. At sunset Venus will be only 5º above the horizon at sunset and will set at 8:25 PM. We will await its dramatic reappearance in the morning sky in early November. Saturn will be in the eastern sky as it gets dark. It is the brightest starlike object low in that direction. It will be below the four stars that make large distinctive pattern, that marks the body of Pegasus the flying horse, called the Great Square of Pegasus. At 6 AM, Jupiter will be due east. Jupiter is brightest and lowest while Mars will be just below and nearly in line with Castor and Pollux of Gemini.
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: 09/22/2026 – Autumn will fall upon us tonight
This is Ephemeris for Tuesday, September 22nd. Today the Sun will be up for 12 hours and 10 minutes, setting at 7:40, and it will rise tomorrow at 7:31. The Moon, half way from first quarter to full, will set at 3:58 tomorrow morning.
The season of fall is about to, ah well, fall upon us and in a few weeks so will the leaves. At 8:06 this evening (00:06 UT tomorrow) the Sun will cross the celestial equator heading south. The celestial equator is an imaginary line in the sky above the earth’s equator. At that point, the Sun will theoretically set at the North Pole and rise at the South Pole. The day is called the autumnal equinox and the daylight hours today is 12 hours and 10 minutes instead of 12 hours exactly. That’s due to our atmosphere and our definition of sunrise and sunset. The reason for the cooler weather now and the cold weather this winter is that the length of daylight is shortening, and the Sun rides lower in the sky, spreading its heat over a larger area, thus diluting its intensity.
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: 09/21/2026 – What is an ephemeris?
This is Ephemeris for Monday, September 21st. Today the Sun will be up for 12 hours and 13 minutes, setting at 7:41, and it will rise tomorrow at 7:30. The Moon, 3 days past first quarter, will set at 2:49 tomorrow morning.
I’ve given the name of this program as being Ephemeris, which is a rather obscure term. A related word, ephemeral, an adjective, may be more familiar, meaning something that lasts a brief period of time, no more than a day. The word ephemeris itself comes from the Greek, and picked up by the Romans meaning a diary. In astronomy an ephemeris a tabular list of daily positions of astronomical objects, which part of this program really does with the rising and setting times of the sun and moon. The request of the station back in 1975 when I started this, was just to get sunrises and sunsets, I’ve added an astronomical tidbit. Now, of course, you can get sunrises and sunsets for your precise location from your smartphone.
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
The columns represent, from left to right: The date and time, and then the position R.A. is Right Ascension which is the east-west position of the object in the sky in hours, minutes, and seconds where an hour is 15 degrees. The next three columns are the declination which is the north-south position in degrees, minutes, and seconds. Plus meaning north of the celestial equator T-mag is total magnitude or brightness of the comet, and seventeen is very dim, N-mag is the magnitude of the nucleus which is not applicable here. Small r is the distance from the sun an astronomical units. The Earth’s mean distance from the Sun is 1. I don’t know what rdot is and I wouldn’t need it for finding the comet. The example is truncated in width. Another column, Delta, is the comet’s distance from the earth.
Ephemeris: 09/18/2026 – The Moon will be lower than the winter solstice Sun tonight
This is Ephemeris for Friday, September 18th. Today the Sun will be up for 12 hours and 22 minutes, setting at 7:47, and it will rise tomorrow at 7:26. The Moon, at first quarter today, will set at 11:40 this evening.
Tonight’s first quarter moon will appear low in the southern sky at its highest at about 11 minutes before sunset tonight. The moon is in the part of the sky where the sun will be on the first day of winter, December 21st at it’s lowest and the moon will be even lower tonight. For us, in Northern Michigan that’s 15 degrees, or one and a half times the width of a fist held at arms length. The moon, though, is even lower than the sun will be that day. The sun will be 22º above the southern horizon that day, a bit more than two fist widths above the southern horizon. I talk a lot about angles on this program, because measuring angles is what astronomers did before the invention of the telescope. A telescope allows better precision, among other attributes.
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
As readers of this blog may have surmised, I’m facinated by angles in the sky.
