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Ephemeris: 12/31/2024 – Previewing January’s skies
This is Ephemeris for New Year’s Eve, Tuesday, December 31st. The Sun will rise at 8:20. It’ll be up for 8 hours and 52 minutes, setting at 5:12. The Moon, 1 day past new, will set at 5:46 this evening.
Let’s look ahead at the month of January 2025. Thursday we will have our latest sunrise at 8:20. That time will drop to 8:02 by the 31st. Sunset times are already increasing. On the 1st at 5:13, will extend to 5:50 at month’s end, which will push the daylight hours to 9 hours 47 minutes by then. The altitude of the Sun at local noon will increase from under 23 degrees tomorrow to 28 degrees at month’s end. Tomorrow we will reach our closest distance from the Sun of the year at 91.4 million miles. Friday morning will see the peak of the Quadrantid meteor shower. They will be best seen in the early morning and seem to come from near the handle of the Big Dipper, where possibly more than 60 meteors an hour might be seen.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
January Evening Star Chart
The planets and stars are plotted for the 15th at 9 PM EST in the evening and 6 AM on the 16th 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), so the skies may not exactly match as seen from other locations.
January 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.
- The leaky bowl of the 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.
- QuadR on the star charts is the radiant of the Quadrantid meteor shower which peaks on the 4th at 4:14 a.m. EST (9:14 UT).
Twilight Limits, Nautical and Astronomical
| EST | |||||||
| Morning | Twilight | Evening | Twilight | Dark | Night | Moon | |
| Date | Astro. | Nautical | Nautical | Astro. | Start | End | Illum. |
| 2025-01-01 | 6h35m | 7h11m | 18h22m | 19h02m | 19h03m | 6h35m | 0.06 |
| 2025-01-02 | 6h35m | 7h11m | 18h23m | 19h02m | 20h21m | 6h35m | 0.12 |
| 2025-01-03 | 6h35m | 7h11m | 18h24m | 19h03m | 21h38m | 6h35m | 0.2 |
| 2025-01-04 | 6h35m | 7h11m | 18h25m | 19h04m | 22h54m | 6h35m | 0.3 |
| 2025-01-05 | 6h35m | 7h11m | 18h26m | 19h05m | – | 6h35m | 0.41 |
| 2025-01-06 | 6h35m | 7h11m | 18h27m | 19h06m | 0h10m | 6h35m | 0.53 |
| 2025-01-07 | 6h35m | 7h11m | 18h28m | 19h07m | 1h27m | 6h35m | 0.64 |
| 2025-01-08 | 6h35m | 7h10m | 18h29m | 19h08m | 2h45m | 6h35m | 0.74 |
| 2025-01-09 | 6h35m | 7h10m | 18h30m | 19h09m | 4h06m | 6h35m | 0.84 |
| 2025-01-10 | 6h35m | 7h10m | 18h31m | 19h10m | 5h26m | 6h35m | 0.91 |
| 2025-01-11 | 6h35m | 7h10m | 18h32m | 19h11m | – | – | 0.96 |
| 2025-01-12 | 6h34m | 7h09m | 18h33m | 19h12m | – | – | 0.99 |
| 2025-01-13 | 6h34m | 7h09m | 18h34m | 19h13m | – | – | 1 |
| 2025-01-14 | 6h34m | 7h09m | 18h35m | 19h14m | – | – | 0.98 |
| 2025-01-15 | 6h34m | 7h08m | 18h36m | 19h15m | 19h15m | 19h28m | 0.94 |
| 2025-01-16 | 6h33m | 7h08m | 18h37m | 19h16m | 19h16m | 20h38m | 0.89 |
| 2025-01-17 | 6h33m | 7h07m | 18h38m | 19h17m | 19h17m | 21h45m | 0.82 |
| 2025-01-18 | 6h32m | 7h07m | 18h39m | 19h18m | 19h18m | 22h49m | 0.74 |
| 2025-01-19 | 6h32m | 7h06m | 18h41m | 19h19m | 19h19m | 23h52m | 0.65 |
| 2025-01-20 | 6h31m | 7h06m | 18h42m | 19h20m | 19h20m | – | 0.56 |
| 2025-01-21 | 6h31m | 7h05m | 18h43m | 19h21m | 19h21m | 0h56m | 0.47 |
| 2025-01-22 | 6h30m | 7h05m | 18h44m | 19h23m | 19h23m | 2h01m | 0.37 |
| 2025-01-23 | 6h29m | 7h04m | 18h45m | 19h24m | 19h24m | 3h08m | 0.28 |
| 2025-01-24 | 6h29m | 7h03m | 18h47m | 19h25m | 19h25m | 4h16m | 0.2 |
| 2025-01-25 | 6h28m | 7h02m | 18h48m | 19h26m | 19h26m | 5h22m | 0.12 |
| 2025-01-26 | 6h27m | 7h02m | 18h49m | 19h27m | 19h27m | 6h24m | 0.06 |
| 2025-01-27 | 6h26m | 7h01m | 18h50m | 19h28m | 19h28m | 6h26m | 0.02 |
| 2025-01-28 | 6h26m | 7h00m | 18h51m | 19h30m | 19h30m | 6h26m | 0 |
| 2025-01-29 | 6h25m | 6h59m | 18h53m | 19h31m | 19h31m | 6h25m | 0.01 |
| 2025-01-30 | 6h24m | 6h58m | 18h54m | 19h32m | 19h32m | 6h24m | 0.04 |
| 2025-01-31 | 6h23m | 6h57m | 18h55m | 19h33m | 20h40m | 6h23m | 0.09 |
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
Date Time Event
Jan 1 We Venus: 47° E
3 Fr 10:24 AM Moon-Venus: 1.5° N
3 Fr 10:24 AM Quadrantid Shower: ZHR = 120
4 Sa 2:59 AM Perihelion: 0.9833 AU
4 Sa 12:18 PM Moon-Saturn: 0.7° S
5 Su 2:46 PM Moon Ascending Node
6 Mo 6:56 PM First Quarter
7 Tu 6:35 PM Moon Perigee: 370200 km
9 Th 8:01 PM Moon-Pleiades: 0.3° S
9 Th 10:59 PM Venus Greatest Elongation: 47.2° E
11 Sa 11:30 PM Moon North Dec.: 28.5° N
13 Mo 4:45 PM Moon-Pollux: 2.2° N
13 Mo 5:27 PM Full Moon
13 Mo 10:42 PM Moon-Mars: 0.2° S Occultation!
14 Tu 4:03 PM Moon-Beehive: 2.7° S
15 We 8:17 PM Mars Opposition
16 Th 9:57 AM Moon-Regulus: 2.4° S
18 Sa 10:53 AM Venus-Saturn: 2.2° N
18 Sa 8:48 PM Moon Descending Node
20 Mo 10:53 PM Moon-Spica: 0.1° N
20 Mo 11:55 PM Moon Apogee: 404300 km
21 Tu 3:31 PM Last Quarter
23 Th 12:05 PM Mars-Pollux: 2.4° S
24 Fr 6:34 PM Moon-Antares: 0.3° N
26 Su 8:27 AM Moon South Dec.: 28.5° S
29 We 7:36 AM New Moon
31 Fr 5:02 PM Jupiter-Aldebaran: 5.2° N
31 Fr 11:46 PM Moon-Saturn: 1.1° S
Feb 1 Sa Venus: 45° E
All event times are given for UTC-5 Eastern Standard Time.
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
January, 2025 Local time zone: EST
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Wed 1| 08:20a 05:13p 08:53 | 06:23p 07:09a | Set 07:02p 5%|
|Thu 2| 08:20a 05:14p 08:54 | 06:24p 07:09a | Set 08:20p 11%|
|Fri 3| 08:20a 05:15p 08:55 | 06:25p 07:10a | Set 09:37p 19%|
|Sat 4| 08:20a 05:16p 08:56 | 06:26p 07:10a | Set 10:54p 28%|
+------+-----------------------+----------------+-----------------------+
|Sun 5| 08:19a 05:17p 08:57 | 06:27p 07:10a | Set 12:09a 39%|
|Mon 6| 08:19a 05:18p 08:58 | 06:28p 07:09a |F Qtr Set 01:26a 50%|
|Tue 7| 08:19a 05:19p 08:59 | 06:29p 07:09a | Set 02:45a 61%|
|Wed 8| 08:19a 05:20p 09:01 | 06:30p 07:09a | Set 04:05a 72%|
|Thu 9| 08:18a 05:21p 09:02 | 06:31p 07:09a | Set 05:25a 82%|
|Fri 10| 08:18a 05:22p 09:04 | 06:32p 07:09a | Set 06:40a 89%|
|Sat 11| 08:18a 05:23p 09:05 | 06:33p 07:09a | Set 07:43a 95%|
+------+-----------------------+----------------+-----------------------+
|Sun 12| 08:17a 05:25p 09:07 | 06:34p 07:08a | Set 08:34a 99%|
|Mon 13| 08:17a 05:26p 09:08 | 06:35p 07:08a |Full Rise 05:00p 100%|
|Tue 14| 08:16a 05:27p 09:10 | 06:36p 07:08a | Rise 06:14p 99%|
|Wed 15| 08:16a 05:28p 09:12 | 06:37p 07:07a | Rise 07:27p 95%|
|Thu 16| 08:15a 05:30p 09:14 | 06:38p 07:07a | Rise 08:37p 90%|
|Fri 17| 08:15a 05:31p 09:16 | 06:39p 07:06a | Rise 09:44p 83%|
|Sat 18| 08:14a 05:32p 09:18 | 06:40p 07:06a | Rise 10:48p 76%|
+------+-----------------------+----------------+-----------------------+
|Sun 19| 08:13a 05:34p 09:20 | 06:42p 07:05a | Rise 11:52p 67%|
|Mon 20| 08:13a 05:35p 09:22 | 06:43p 07:05a | Rise 12:56a 58%|
|Tue 21| 08:12a 05:36p 09:24 | 06:44p 07:04a |L Qtr Rise 02:01a 49%|
|Wed 22| 08:11a 05:38p 09:26 | 06:45p 07:03a | Rise 03:07a 39%|
|Thu 23| 08:10a 05:39p 09:28 | 06:46p 07:03a | Rise 04:15a 30%|
|Fri 24| 08:09a 05:40p 09:31 | 06:48p 07:02a | Rise 05:22a 22%|
|Sat 25| 08:08a 05:42p 09:33 | 06:49p 07:01a | Rise 06:24a 14%|
+------+-----------------------+----------------+-----------------------+
|Sun 26| 08:07a 05:43p 09:35 | 06:50p 07:00a | Rise 07:17a 8%|
|Mon 27| 08:06a 05:44p 09:38 | 06:51p 07:00a | Rise 08:00a 3%|
|Tue 28| 08:05a 05:46p 09:40 | 06:52p 06:59a | Rise 08:34a 0%|
|Wed 29| 08:04a 05:47p 09:42 | 06:54p 06:58a |New Set 06:00p 0%|
|Thu 30| 08:03a 05:49p 09:45 | 06:55p 06:57a | Set 07:20p 3%|
|Fri 31| 08:02a 05:50p 09:47 | 06:56p 06:56a | Set 08:39p 8%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise
Generated using my LookingUp for DOS program.
Ephemeris: 12/30/2024 – Two great astronomical events of 2024
This is Ephemeris for Monday, December 30th. Today the Sun will be up for 8 hours and 51 minutes, setting at 5:11, and it will rise tomorrow at 8:20. The Moon is new today, and won’t be visible.
Speaking of new moons, the most spectacular astronomical event of 2024 was the total solar eclipse of April 8th. The path of totality came fairly close to us here in Northern Michigan just clipping the southeastern corner of the state. It was my sixth observation of a total solar eclipse out of six tries and probably my last, because our next total solar eclipse in the contiguous 48 states will be twenty-one years from now in 2045. The other event of 2024 was the appearance of the Comet Tsuchinshan-ATLAS which graced our skies for a few days in mid-October. I have no reports of anybody seeing it with the naked eye, however it was visible in binoculars and easily photographed with a few seconds exposure with a camera. It had a very prominent tail.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/27/2024 – Orion’s story
This is Ephemeris for Friday, December 27th. Today the Sun will be up for 8 hours and 49 minutes, setting at 5:09, and it will rise tomorrow at 8:19. The Moon, 3 days before new, will rise at 6:32 tomorrow morning.
It may seem unfair that the greatest mythological hero Hercules gets a little constellation of dim stars on the border between the spring and summer constellations, while Orion, a virtual nobody, a hard luck hero gets the splashiest constellation in the sky. Orion’s claim to fame or infamy is how he died. And the Greeks had two completely different stories on how that happened. First, that he was killed by a sting of a giant scorpion represented by the constellation Scorpius, and second that he was killed by an arrow shot by the goddess he loved, the arrow being deflected by her brother who didn’t want her to marry a mere mortal.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/26/2024 – Finding Orion the hunter
This is Bob Moler with Ephemeris for Thursday, December 26th. Today the Sun will be up for 8 hours and 49 minutes, setting at 5:08, and it will rise tomorrow at 8:19. The Moon, halfway from last quarter to new, will rise at 5:24 tomorrow morning.
The constellation of Orion the hunter is the most famous constellation in the sky. At 8 o’clock tonight he is seen in the east southeast. Two of its stars are first magnitude, among the brightest in the sky while five are second magnitude, as bright as the brightest Big Dipper stars. His torso is a rectangle of stars, now tilted to the left, framed by Betelgeuse and Bellatrix in his shoulders and Rigel and Saiph and Rigel at his knees. Betelgeuse and Rigel are first magnitude stars at opposite corners of that rectangle. His most easily found feature is his belt of three stars in a straight line in the center of that rectangle, now nearly vertically aligned, which makes them easy to spot even if you don’t know the pattern of the rest of the stars.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/25/2024 – A Christmas week look at the naked-eye planets
This is Ephemeris for Christmas Day, Wednesday, December 25th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:19. The Moon, 3 days past last quarter, will rise at 4:16 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted in the south-southwestern sky by 5:30 PM, about 30 minutes after sunset. It will set at 8:41 PM. Saturn will be in the south at 6 PM, way above the bright star Fomalhaut. Jupiter is low in the east-northeast, about the same time Venus is first spotted. It will be a good object for the small telescope about an hour later. Mars, rises tonight at 7:44, It will appear above the Moon in the evening. Mars is still considered a morning planet since it is still up at sunrise. By 6:00 AM tomorrow Jupiter will be low in the west-northwest, to the right of the setting Orion, while reddish Mars will be high in the west-southwest.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/24/2024 – Looking at another possibility for the Star of Bethlehem
This is Ephemeris for Christmas Eve, Tuesday, December 24th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:18. The Moon, 2 days past last quarter, will rise at 3:10 tomorrow morning.
Many writers of the 2nd and 3rd centuries CE place Jesus’ birth, via Roman events, around 2 BCE. So the Star of Bethlehem could appear several years later than the triple conjunction of Jupiter and Saturn in 7 BCE that’s been popular. In 3 and again in 2 BCE there were star-like conjunctions or apparent joining of the planets Jupiter and Venus against the backdrop of the constellation of Leo the Lion. A lion is related to Judah, son of Jacob, by a blessing the latter gave his 12 sons in Genesis. The first conjunction occurred in August in the morning sky. On June 16th of the next year the two planets got together again, this time in the evening sky, a month or more after Jesus would have been born in the vulnerable spring lambing season when shepherds would most likely be out at night guarding the flocks, not December 25th.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
An edited excerpt from this year’s Star of Bethlehem presentation I gave to the Grand Traverse Astronomical Society on December 6th.
The triple conjunction of Jupiter and Saturn in 7 BCE is the generally accepted Star of Bethlehem, with Jesus being born in 6 or 5 BCE and Herod’s death being in 4 BCE after a lunar eclipse. What if the lunar eclipse in question was in 1 BCE? If so, there is that other possibility. It involves the constellation Leo, which is a lion. There is a passage in Genesis in which Jacob, who, by this time, is called Israel, is blessing his sons, each the heads of the twelve tribes of Israel. In Genesis 49 9-10 He compares him to a lion cub, the king of beasts, from whom the leaders of Israel will come. We can make a connection between Judah and the celestial lion, Leo. Let’s take a look at the celestial happenings against the constellation of Leo with Jupiter and Venus in 3 and 2 BCE.
On August 12th of 3 BCE Jupiter and Venus appeared to come together so close as to be separable only in telescopes. This may have been the Star at its rising mentioned to Herod. Could this predawn celestial mating of Jupiter, who the Babylonians saw as the god Marduk and Venus as Ishtar, the goddess of fertility, to bring forth a powerful king? The Magi, I’m pretty sure, would have known that 10 months later, a little longer than the human gestation period, by the way, that the two planets would again come together.
Ten months after the first conjunction of Jupiter and Venus, perhaps as the Magi neared Jerusalem, they saw Jupiter and Venus approaching each other again. Later as they left Herod’s palace on the evening of June 16th, 2 BCE the conjunction was at its tightest. They saw the “Star” again, as Matthew relates. Telescopes, which wouldn’t be invented for another sixteen hundred years, could have seen this extremely close conjunction of Jupiter and Venus. Venus, near its greatest eastern elongation from the Sun, would appear half illuminated. But even to the best naked eye observer, Jupiter and Venus would merge into a single star. Venus was much brighter than Jupiter than it appears here. In fact, it was nearly twelve times brighter, so Jupiter’s added brightness wouldn’t contribute much to the combined brightness. Jupiter would seem to disappear at their closest.
Also, there was a conjunction of Jupiter with the “Little King” star Regulus on September 14th 3 BCE, one or two days after the beginning of the Jewish New Year. Was this another sign that a new King of the Jews would be born? It is actually the first of three conjunctions Jupiter has with Regulus in the next 9 months. Yes, another triple conjunction. Jupiter passed Regulus the second time on February 17, of 2 BCE and for a final time on May 9th. During this time Venus had moved back toward the Sun and entered the evening sky where Jupiter met it once again.
Ephemeris: 12/23/2024 – What was the Star of Bethlehem? Part 1
This is Ephemeris for Monday, December 23rd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:06, and it will rise tomorrow at 8:18. The Moon, 1 day past last quarter, will rise at 2:05 tomorrow morning.
The most popular solution to what the Star of Bethlehem may have been, is a triple conjunction of Jupiter and Saturn that occurred in 7 BCE, where Jupiter passed Saturn three times in a few months time. So the event should more probably be called a celestial sign, rather than a star. The conjunction occurred against the constellation of Pisces the fish which was thought to represent the Jews or whoever lived in that area. Such a series of conjunctions against a particular zodiacal constellation would occur only about once every 800 to 900 years. Triple conjunctions aren’t super rare, if you don’t care which constellation it’s happening in front of. We had one in 1981, but it was against the constellation of Virgo.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/20/2024 – Winter is coming tomorrow!
Dec 20. This is Bob Moler with Ephemeris for Friday, December 20th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:17. The Moon, 2 days before last quarter, will rise at 10:55 this evening.
Today is the last full day of autumn. Tomorrow at 4:40 a.m. winter will begin as the Sun passes the winter solstice and stops its southward movement in the sky. Immediately it will slowly climb northward again. It will lengthen the daytime hours and increase the power of the Sun as it gets higher in our sky. The cooling of the Northern Hemisphere will continue until late January, on average, until the lengthening days and increased solar altitude will finally overcome it. Ancient cultures weren’t all that sure that the Sun would come back, since they didn’t understand what was really happening. So when the solstice finally arrived it was a time for great celebrations which survive to this day.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Ephemeris: 12/19/2024 – Jupiter’s dark moon Callisto
This is Bob Moler with Ephemeris for Thursday, December 19th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:16. The Moon, 3 days before last quarter, will rise at 9:47 this evening.
Callisto is the most distant of the Galilean moons from Jupiter, visible in small telescopes or even binoculars. It has the darkest surface of the four moons, and so appears the dimmest, even though it’s the second largest after Ganymede. The largest crater on Callisto is called Valhalla, and it doesn’t look like a crater at all. There’s many concentric, what look like, frozen ripples surrounding it, and it covers a good percentage of the moon’s surface. It is probably the only moon of Jupiter that we could send a crew to, since it’s the farthest from the intense radiation belts of Jupiter. Made of approximately equal parts of water mostly in the form of ice and rock, Callisto probably has a liquid water ocean underneath its icy crust, like Ganymede and Europa.
Addendum
Ephemeris: 12/18/2024 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, December 18th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:03, and it will rise tomorrow at 8:16. The Moon, 3 days past full, will rise at 8:36 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted in the south-southwestern sky by 5:30 PM, about 30 minutes after sunset. It will set at 8:41 PM. Saturn will be in the south at 6 PM, way above the bright star Fomalhaut. Jupiter is low in the east-northeast, about the same time Venus is first spotted. It will be a good object for the small telescope about an hour later. Mars, rises tonight at 7:44, It will appear above the Moon in the evening. Mars is still considered a morning planet since it is still up at sunrise. By 6:00 AM tomorrow Jupiter will be low in the west-northwest, to the right of the setting Orion, while reddish Mars will be high in the west-southwest.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
Bob Moler's Ephemeris Blog 