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Ephemeris: 10/09/2024 – Where are the naked-eye planets this week?

October 9, 2024 Comments off

This is Ephemeris for Wednesday, October 9th. Today the Sun will be up for 11 hours and 16 minutes, setting at 7:07, and it will rise tomorrow at 7:52. The Moon, 1 day before first quarter, will set at 10:57 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest only 7° above the horizon at 8 PM, 55 minutes after sunset. It will set at 8:23. Saturn will be in the southeast at that time. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet like it’s stapled onto the sky. Jupiter and Mars will be up in the morning sky, with Jupiter rising about 10:08 PM in the east-northeast. By 7 AM tomorrow, Jupiter will be brighter than any of the winter stars high in the south. Mars, with its reddish hue, will be to the left of Jupiter. Comet Tsuchinshan-ATLAS will be in the western evening sky starting this weekend. It is expected to be quite bright, I’m betting with a broad tail.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Venus and the Moon in evening twilight, approximately an hour after sunset. For the Grand Traverse area of Michigan that would be about 8 PM tonight, October 9, 2024, where Venus, is only 7 degrees above the horizon at sunset. It would be higher from the south of us, below 45° N latitude, and lower for those north of us. Created using Stellarium.
Saturn as it would appear at 8 PM tonight, October 9, 2024, low in east southeast to southeast. With the naked eye it would seem to be pretty much alone in that sector of the sky of dim stars. Created using Stellarium.
Though not visible tonight, the comet will be making an evening appearance at the end of the week. The track of comet C/2023 A3 (Tsuchinshan-ATLAS) for five nights at 8 pm starting with Saturday the 12th. It might be visible on the 11th but the sky might be too bright. On that date we might be able to see the tail without seeing the head of the comet in the twilight. It should be interesting. The bright track on the lower left is Venus. Each label is the date and estimated magnitude. The comet is expected to be brighter that those estimates, especially during the first week of its appearance. Created using Stellarium.
The Moon as it might appear through a small telescope tonight, October 9, 2024. Selected features are labeled. Created using stellarium, LibreOffice draw, and GIMP.
Mars and Jupiter among the bright winter stars, and above the constellation of Orion with its bright stars Betelgeuse and Rigel 7:00 AM tomorrow morning, October 10, 2024. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from 8 pm, and Jupiter for 11 pm tonight, October 9, 2024. Apparent diameters: Venus 12.7″, 82.5% illuminated; Saturn 18.9″, its rings 44.0″, 4.8 degrees from edge on (opening up a bit); Jupiter 43.5″; Mars, too small to be represented here, is 8.0″. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on October 9, 2024. The night ends on the left with sunrise on the 10th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, October 9 and 10, 2024. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Ephemeris: 10/08/2024 – Comet Tsuchinshan-ATLAS may be brighter than expected

October 8, 2024 Comments off

This is Ephemeris for Tuesday, October 8th. Today the Sun will be up for 11 hours and 19 minutes, setting at 7:09, and it will rise tomorrow at 7:51. The Moon, 2 days before first quarter, will set at 10:00 this evening.

You are going to hear a lot about a bright comet visible in the evening starting this weekend. The comet with a long name Tsuchinshan-ATLAS will begin to be visible in the evening sky, and it will be very bright. It will be the brightest comet we’ve had in some time visible in the Northern Hemisphere since Comet Hale-Bopp in 1997. The reason for this comet’s great brightness is that the comet is passing between the Earth and the Sun. This comet is very dusty with an extensive dust tail. Since the comet is passing between the Earth and Sun the dust scatters sunlight in a forward direction like seeing sunbeams through holes in the clouds near sunset. This is making the comet brighter than originally predicted.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

The track of comet C/2023 A3 (Tsuchinshan-ATLAS) for five nights
The track of comet C/2023 A3 (Tsuchinshan-ATLAS) for five nights at 8 pm starting with Saturday the 12th. It might be visible on the 11th but the sky might be too bright. On that date we might be able to see the tail without seeing the head of the comet in the twilight. It should be interesting. The bright track on the lower left is Venus. Each label is the date and estimated magnitude. The comet is expected to be brighter that those estimates, especially during the first week of its appearance. Created using Stellarium.
The inner solar system with the paths of the planets and Comet Tsuchinshan-ATLAS
The inner solar system with the paths of the planets and Comet Tsuchinshan-ATLAS. The diagram is from the Jet Propulsion Laboratory Small-Body Database. I’ve added the direction arrows for the motion of the comet and the Earth. The positions of these bodies are for 8:00 PM tonight, October 8th 2024. Click or tap on the image to enlarge it. Created from the NASA/JPL interactive image, LibreOffice Draw, and GIMP.

Ephemeris: 10/04/2024 – GTAS meeting & star party tonight

October 4, 2024 Comments off

This is Bob Moler with Ephemeris for Friday, October 4th. Today the Sun will be up for 11 hours and 31 minutes, setting at 7:16, and it will rise tomorrow at 7:46. The Moon, 2 days past new, will set at 7:51 this evening. | The Grand Traverse Astronomical Society will host its October meeting tonight at 8:00 PM at Northwestern Michigan College’s Joseph H Rogers Observatory, featuring the society’s Library Telescope program. For over five years now the society has given small telescopes to a number of local libraries and branches to lend out. It has been quite successful. After the meeting, about 9 PM if it’s clear, there will be viewing of the heavens through the observatory’s telescopes, featuring Saturn and the wonders of the Milky Way, including nebulae, open and globular star clusters, containing hundreds to hundreds of thousands of stars. The observatory is located on Birmley Rd. South of Traverse City between Garfield and Keystone roads.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

A library telescope in use at a star party.
A library telescope in use at a star party at the Betsie Valley District Library in Thompsonville MI. Photo by the Eileen Carlisle.

Ephemeris: 10/03/2024 – Capella rising

October 3, 2024 Comments off

This is Ephemeris for Thursday, October 3rd. Today the Sun will be up for 11 hours and 34 minutes, setting at 7:18, and it will rise tomorrow at 7:45. The Moon, 1 day past new, will set at 7:33 this evening.

There is a bright star low in the northeast these evenings. It doesn’t seem to be rising very much over the course of the evening. This star is Capella, whose name means “little goat” and is part of the constellation Auriga the charioteer, which won’t completely rise for until about 11 PM. Capella is a circumpolar star meaning it appears to go around the North Pole of the sky, in a circle, as the Earth rotates but never sets. This is true for the Interlochen/Traverse City area and for latitudes north of the city of Ludington. Capella is slowly rising from the bottom of its circumpolar circle in the north, so it’s moving more horizontally than it is rising up. This motion was suspicious to one person who called me, who wondered what it was.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

The first magnitude star Capella is shown rising in the north-northeast
The first magnitude star Capella is shown rising in the north-northeast over an hour and a quarter from 7:45 PM to 9 o’clock. Capella is the 6th brightest star in the sky and the most northerly of first magnitude stars. It is a winter star and is a constant reminder here in Northern Michigan that winter will soon be here. Created using Stellarium and GIMP.

Ephemeris: 10/02/2024 – Taking our weekly look at where the naked-eye planets are

October 2, 2024 Comments off

This is Ephemeris for Wednesday, October 2nd. Today the Sun will be up for 11 hours and 37 minutes, setting at 7:20, and it will rise tomorrow at 7:43. The Moon is new today, and won’t be visible.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest only 7° above the horizon at 7:45 PM, 35 minutes after sunset. It will set at 8:30. Saturn will be low in the east-southeast at that time, but you might have to wait another half hour for it to appear. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet like it’s stapled onto the sky. Jupiter and Mars will be up in the morning sky, with Jupiter rising about 10:30 PM now in the east-northeast and by 7 AM tomorrow, Jupiter will be brighter than the winter stars high in the south. Mars will be left of Jupiter. Comet Tsuchinshan-ATLAS is very low in the east at that hour, but probably too faint to spot.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Venus in evening twilight
Venus in evening twilight, approximately 25 minutes after sunset. For the Grand Traverse area of Michigan that would be about 7:45 PM, where Venus is very close to the horizon, due to the low angle of the ecliptic. Created using Stellarium.
Saturn in the southeastern sky by 9 pm. Created using Stellarium
The morning planets Jupiter and Mars are seen among the winter stars at 7 AM or about an hour before sunrise in the South southeast. Though Comet Tsuchinshan-ATLAS is shown, it is too low and faint to be able to spot. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 2nd 2024, Jupiter is for 7 am on the 3rd. Apparent diameters: Venus 12.4″, 84.3% illuminated; Saturn 19.0″, its rings 44.3″, 4.3 degrees from edge on (opening up a bit); Jupiter 42.6″; Mars, too small to be represented here, is 7.7″. Saturn’s rings are actually much brighter than depicted here. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on October 2, 2024. The night ends on the left with sunrise on the 3rd. Comet Tsuchinshan-ATLAS is moving northeastward in the sky. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, October 2 and 3, 2024. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Ephemeris: 10/01/2024 – Previewing the skies of October

October 1, 2024 Comments off

This is Ephemeris for Tuesday, October 1st. Today the Sun will be up for 11 hours and 40 minutes, setting at 7:22, and it will rise tomorrow at 7:42. The Moon, 1 day before new, will rise at 7:30 tomorrow morning.

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 40 minutes today to 10 hours, 11 minutes at month’s end. The altitude of the Sun above the southern horizon at local noon will be 42 degrees today, and will descend to 31 degrees on Halloween, also in the Interlochen area. Sunrise times will increase from 7:41 today all the way to 8:20 a.m. in Interlochen and Traverse City on the 31st. Sunset times will decrease from 7:22 p.m. today to 6:32 on Halloween.

The big event of October will be the appearance of Comet Tsuchinshan-ATLAS in the evening sky which may become quite bright, but being a comet, all bets are off until you actually see it. It will become visible in the evening sky starting October 12th.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

October path of Comet Tsuchinshan-ATLAS

The track of Comet Tsuchinshan-ATLAS from October 12th through November 1st. The position of the stars are set for October 12th at 8 PM. The dates are the day of the month except the first and last entries which is year, month as a Roman numeral, and day. The number in parentheses is the magnitude of the comet. I wouldn’t believe it, but you can see how the comet gets dimmer as it goes through the month (remembering that the higher the magnitude number the dimmer the comet). Created using Stellarium.

October Evening Star Chart

Star Chart for October evenings 2024
Star Chart for October 2024. Click or tap on the image to enlarge it. Created using my LookingUp program.

The planets and stars are plotted for the 15th at 9 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

Star Chart for October mornings 2024
Star Chart for October mornings 2024. Click on the image to enlarge it. Created using my LookingUp program.

or 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.
  • The Summer Triangle is in red.
  • DracR – Draconid Radiant – Peaks the 8th – Zenithal Hourly Rate < 10 with rare outbursts of a thousand an hour. It’s hindered this year by the full moon.
  • OriR – Orionid Radiant – Peak 21st – Zenithal Hourly Rate = 20

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning Twilight Evening Twilight Dark Night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2024-10-01 6h06m 6h40m 20h28m 21h03m 21h03m 6h06m 0.00
2024-10-02 6h07m 6h41m 20h27m 21h01m 21h01m 6h07m 0.00
2024-10-03 6h08m 6h42m 20h25m 20h59m 20h59m 6h08m 0.02
2024-10-04 6h09m 6h43m 20h23m 20h57m 20h57m 6h09m 0.05
2024-10-05 6h11m 6h45m 20h21m 20h55m 20h55m 6h11m 0.10
2024-10-06 6h12m 6h46m 20h19m 20h53m 20h53m 6h12m 0.17
2024-10-07 6h13m 6h47m 20h17m 20h51m 21h15m 6h13m 0.25
2024-10-08 6h14m 6h48m 20h16m 20h50m 22h01m 6h14m 0.34
2024-10-09 6h16m 6h50m 20h14m 20h48m 22h58m 6h16m 0.44
2024-10-10 6h17m 6h51m 20h12m 20h46m 6h17m 0.55
2024-10-11 6h18m 6h52m 20h10m 20h44m 0h06m 6h18m 0.65
2024-10-12 6h19m 6h53m 20h09m 20h43m 1h22m 6h19m 0.76
2024-10-13 6h21m 6h54m 20h07m 20h41m 2h42m 6h21m 0.85
2024-10-14 6h22m 6h56m 20h05m 20h39m 4h03m 6h22m 0.92
2024-10-15 6h23m 6h57m 20h04m 20h37m 5h25m 6h23m 0.98
2024-10-16 6h24m 6h58m 20h02m 20h36m 1.00
2024-10-17 6h26m 6h59m 20h00m 20h34m 0.99
2024-10-18 6h27m 7h01m 19h55m 20h33m 0.96
2024-10-19 6h28m 7h02m 19h53m 20h31m 0.89
2024-10-20 6h29m 7h03m 19h52m 20h29m 20h29m 20h40m 0.81
2024-10-21 6h31m 7h04m 19h50m 20h28m 20h28m 21h36m 0.72
2024-10-22 6h32m 7h05m 19h49m 20h26m 20h26m 22h41m 0.62
2024-10-23 6h33m 7h07m 19h47m 20h25m 20h25m 23h51m 0.51
2024-10-24 6h34m 7h08m 19h46m 20h23m 20h23m 0.41
2024-10-25 6h35m 7h09m 19h44m 20h22m 20h22m 1h01m 0.32
2024-10-26 6h37m 7h10m 19h43m 20h21m 20h21m 2h10m 0.23
2024-10-27 6h38m 7h12m 19h42m 20h19m 20h19m 3h16m 0.16
2024-10-28 6h39m 7h13m 19h40m 20h18m 20h18m 4h19m 0.10
2024-10-29 6h40m 7h14m 19h39m 20h17m 20h17m 5h22m 0.05
2024-10-30 6h41m 7h15m 19h37m 20h15m 20h15m 6h25m 0.02
2024-10-31 6h43m 7h16m 19h36m 20h14m 20h14m 6h43m 0.00

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
Oct 1 Tu Venus: 31.4° E
2 We 7:52 am Moon Descending Node
2 We 2:46 pm Annular Solar Eclipse
2 We 2:49 pm New Moon
2 We 3:40 pm Moon Apogee: 406500 km
5 Sa 4:26 pm Moon-Venus: 3.3° N
7 Mo 2:48 pm Moon-Antares: .2° N
9 We 7:53 am Moon South Dec.: 28.7° S
10 Th 2:55 pm First Quarter
14 Mo 2:05 pm Moon-Saturn: .1° S
16 We 3:05 am Moon Ascending Node
16 We 8:46 pm Moon Perigee: 357200 km
17 Th 7:26 am Full Moon
18 Fr 7:50 pm Mars-Pollux: 5.7° S
19 Sa 3:59 pm Moon-Pleiades: .1° S
21 Mo 1:58 am Orionid Shower: ZHR = 20
21 Mo 8:50 pm Moon North Dec.: 28.7° N
23 We 1:16 pm Moon-Pollux: 1.8° N
23 We 3:55 pm Moon-Mars: 4.2° S
24 Th 4:03 am Last Quarter
24 Th 1:35 pm Moon-Beehive: 3.3° S
25 Fr 7:43 pm Venus-Antares: 3.1° N
29 Tu 12:44 pm Moon Descending Node
29 Tu 5:50 pm Moon Apogee: 406200 km
Nov 1 Fr Venus: 38.2° E

All event times are given for UTC-4 hr: Eastern Daylight Saving 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 Times

     LU                  Ephemeris of Sky Events for Interlochen/TC
October, 2024 Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM |
| | RISE SET HOURS | END START |PHASE SET** TIME FRACTN|
+=======================================================================+
|Tue 1| 07:41a 07:22p 11:40 | 08:25p 06:38a | Rise 07:30a 1%|
|Wed 2| 07:42a 07:20p 11:37 | 08:23p 06:39a |New Set 07:16p 0%|
|Thu 3| 07:43a 07:18p 11:34 | 08:21p 06:40a | Set 07:33p 1%|
|Fri 4| 07:45a 07:16p 11:31 | 08:19p 06:42a | Set 07:51p 4%|
|Sat 5| 07:46a 07:14p 11:28 | 08:17p 06:43a | Set 08:13p 9%|
+------+-----------------------+----------------+-----------------------+
|Sun 6| 07:47a 07:13p 11:25 | 08:15p 06:44a | Set 08:40p 15%|
|Mon 7| 07:48a 07:11p 11:22 | 08:14p 06:45a | Set 09:15p 23%|
|Tue 8| 07:50a 07:09p 11:19 | 08:12p 06:47a | Set 10:00p 32%|
|Wed 9| 07:51a 07:07p 11:16 | 08:10p 06:48a | Set 10:57p 42%|
|Thu 10| 07:52a 07:05p 11:13 | 08:08p 06:49a |F Qtr Set 12:05a 52%|
|Fri 11| 07:53a 07:04p 11:10 | 08:07p 06:50a | Set 01:22a 63%|
|Sat 12| 07:55a 07:02p 11:07 | 08:05p 06:51a | Set 02:41a 73%|
+------+-----------------------+----------------+-----------------------+
|Sun 13| 07:56a 07:00p 11:04 | 08:03p 06:53a | Set 04:03a 83%|
|Mon 14| 07:57a 06:58p 11:01 | 08:02p 06:54a | Set 05:24a 91%|
|Tue 15| 07:58a 06:57p 10:58 | 08:00p 06:55a | Set 06:47a 97%|
|Wed 16| 08:00a 06:55p 10:55 | 07:58p 06:56a | Set 08:11a 100%|
|Thu 17| 08:01a 06:53p 10:52 | 07:57p 06:58a |Full Rise 06:53p 100%|
|Fri 18| 08:02a 06:52p 10:49 | 07:55p 06:59a | Rise 07:21p 96%|
|Sat 19| 08:04a 06:50p 10:46 | 07:54p 07:00a | Rise 07:55p 91%|
+------+-----------------------+----------------+-----------------------+
|Sun 20| 08:05a 06:48p 10:43 | 07:52p 07:01a | Rise 08:40p 83%|
|Mon 21| 08:06a 06:47p 10:40 | 07:50p 07:02a | Rise 09:35p 74%|
|Tue 22| 08:08a 06:45p 10:37 | 07:49p 07:04a | Rise 10:40p 64%|
|Wed 23| 08:09a 06:44p 10:34 | 07:47p 07:05a | Rise 11:50p 53%|
|Thu 24| 08:10a 06:42p 10:31 | 07:46p 07:06a |L Qtr Rise 01:01a 43%|
|Fri 25| 08:12a 06:40p 10:28 | 07:45p 07:07a | Rise 02:09a 34%|
|Sat 26| 08:13a 06:39p 10:25 | 07:43p 07:09a | Rise 03:15a 25%|
+------+-----------------------+----------------+-----------------------+
|Sun 27| 08:14a 06:37p 10:23 | 07:42p 07:10a | Rise 04:19a 17%|
|Mon 28| 08:16a 06:36p 10:20 | 07:40p 07:11a | Rise 05:22a 11%|
|Tue 29| 08:17a 06:34p 10:17 | 07:39p 07:12a | Rise 06:24a 6%|
|Wed 30| 08:18a 06:33p 10:14 | 07:38p 07:14a | Rise 07:28a 2%|
|Thu 31| 08:20a 06:32p 10:11 | 07:36p 07:15a | Rise 08:34a 0%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

Generated using my LookingUp for DOS program.

Ephemeris: 09/27/2024 – Finding Andromeda

September 27, 2024 Comments off

This is Ephemeris for Friday, September 27th. Today the Sun will be up for 11 hours and 53 minutes, setting at 7:29, and it will rise tomorrow at 7:37. The Moon, 3 days past last quarter, will rise at 3:11 tomorrow morning.

The constellation of Andromeda is famous mainly for the galaxy visible to the naked eye that is contained within it, called the Great Andromeda Galaxy, which is actually visible to the naked eye. Andromeda is found in the east northeast these evenings connected to the Great Square of Pegasus, the square of stars standing on one corner in the east. It shares a star with that square called Alpheratz, the leftmost star, and from that star two curved lines of stars are seen to the left that is the body of Andromeda. She was a Princess and daughter of Queen Cassiopeia, and was fated to be devoured by the monster Cetus. She was saved by the hero Perseus who flew in on his flying horse Pegasus.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Locating Andromeda in this animated finder chart
Locating Andromeda in this animated finder chart is by using the Great Square of Pegasus as the starting point. The position of the constellation is for 9 PM in late September. The bright star on the right is not a star, but where Saturn is this year .

Ephemeris: 09/26/2024 – Finding Cassiopeia the queen

September 26, 2024 Comments off

This Ephemeris for Thursday, September 26th. Today the Sun will be up for 11 hours and 56 minutes, setting at 7:31, and it will rise tomorrow at 7:36. The Moon, 2 days past last quarter, will rise at 2:02 tomorrow morning.

High in the northeast sky at 9:00 PM can be found the constellation of Cassiopeia the queen. Its stars make a letter W in the sky. It is circumpolar, meaning that it never sets, as it appears to move around the North Pole of the sky. In the summer it is a W low in the north. It becomes kind of an open and angular number 3 in the autumn. In the winter it is overhead and looks like an M. In springtime it looks like the Greek capital letter Sigma in the northwest. I will visit Cassiopeia later this autumn and relate her story and other autumn constellations including her daughter Andromeda, husband King Cepheus, future son-in-law Perseus and his horse Pegasus, and the sea monster, Cetus.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Cassiopeia finder animation
Cassiopeia finder animation looking in the northeastern sky around 9 PM tonight. One cannot miss the distinctive W, or in this orientation 3. Created using Stellarium.

Ephemeris: 09/25/2024 – Looking for the naked-eye planets for this week

September 25, 2024 Comments off

This is Ephemeris for Wednesday, September 25th. Today the Sun will be up for 11 hours and 59 minutes, setting at 7:33, and it will rise tomorrow at 7:35. The Moon, 1 day past last quarter, will rise at 12:53 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest only 6° above the horizon at 8 PM, 30 minutes after sunset. It will set at 8:38. Saturn will be low in the east-southeast at that time, but you might have to wait another half hour for it to appear. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet like it’s stapled onto the sky. Jupiter and Mars will be up in the morning sky, with Jupiter rising about 11 PM now and by 6:30 AM tomorrow, Jupiter will be brighter than the winter stars in the south-southeast. Mars and the Moon will be left and below Jupiter.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Venus in evening twilight
Venus in evening twilight, approximately 30 minutes after sunset. For the Grand Traverse area of Michigan that would be about 8 PM, where Venus is very close to the horizon, due to the low angle of the ecliptic. Created using Stellarium.
Saturn in the southeastern sky by 9 pm. Created using Stellarium.
The morning planets Jupiter, Mars and the Moon are seen among the winter stars at 6:45 AM or about an hour before sunrise in the South southeast. Though Comet Tsuchinshan-ATLAS ia shown, it is too low and faint to be able to spot. Created using Stellarium.
The Moon two days past last quarter. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 25th 2024, Jupiter is for 6:45 am on the 26th. Apparent diameters: Venus 12.0″, 86.1% illuminated; Saturn 19.0″, its rings 44.5″, 4.4 degrees from edge on (opening up a bit); Jupiter 41.6″; Mars, too small to be represented here, is 7.4″. Saturn’s rings are actually much brighter than depicted here. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 25, 2024. The night ends on the left with sunrise on the 26th. Comet Tsuchinshan-ATLAS is moving northeastward in the sky. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 25 and 26, 2024. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Ephemeris: 09/24/2024 – Pegasus is rising on autumn evenings

September 24, 2024 Comments off

This is Ephemeris for Tuesday, September 24th. Today the Sun will be up for 12 hours and 2 minutes, setting at 7:35, and it will rise tomorrow at 7:34. The Moon, at last quarter today, will rise at 11:47 this evening.

While we’ve been watching the stars and constellations of summer and the Milky Way, the constellations of autumn have been sneaking up on us from the east. About halfway up the sky in the east at 9 PM is one of the greatest constellations of autumn, Pegasus the flying horse. Her body or at least the front part of it is a large square of stars called the Great Square of Pegasus. It is an almost perfect rectangle. However, as she’s rising, it’s standing on one corner. From the upper star are her front legs, from the rightmost star her neck and head extend in the stars. And from the left star of the square are what might look like her hind legs but aren’t. Only half of her body is in the stars. It’s another constellation, Andromeda, which we’ll talk about later.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Pegasus-Andromeda finder
Pegasus & Andromeda animated finder chart for about 9 p.m. in the second half of September. Created using Stellarium and GIMP.