Archive for the ‘Ephemeris Program’ Category

10/03/2018 – Ephemeris – This week’s look at the bright planets

October 3, 2018 Comments off

Ephemeris for Wednesday, October 3rd. The Sun will rise at 7:43. It’ll be up for 11 hours and 36 minutes, setting at 7:19. The Moon, 1 day past last quarter, will rise at 2:02 tomorrow morning

Let’s look at the bright planets today. Three of them are visible in the evening sky. The brilliant Venus will be just too low to spot, setting 29 minutes after the Sun. The problem isn’t its separation from the Sun, but it is also south of the Sun’s path. Jupiter will be in the southwest as it gets dark. The big planet will set at 9:03 p.m. Saturn will start the evening low in the south-southwest sky and will set at 11:31 p.m. I will be giving a talk about Saturn tonight at the Main branch of the library in Traverse City at 7 p.m. Mars will be low in the south-southeast as the skies darken tonight. and is now 56.7 million miles (91.3 million km) away. Mars will be due south at 9:34 p.m., and it will set at 2:03 a.m.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Evening planets
The evening planets at 8:00 p.m. October 3, 2018. Click on image to enlarge. Created using Stellarium.
telescopic planets
Venus, already set; Jupiter, Saturn and Mars with the same magnification at 8:30 p.m.
Binocular Moon
The waning crescent Moon as it should appear by 6 tomorrow morning in binoculars. Created using Stellarium.
Planets and the Moon on a single night
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on October 3, 2018. The night ends on the left with sunrise on the 4th. Click on the image to enlarge. Created using my LookingUp program.

10/02/2018 – Ephemeris – I will give a talk on Saturn at the Traverse Area District Library tomorrow night

October 2, 2018 Comments off

Ephemeris for Tuesday, October 2nd. The Sun will rise at 7:42. It’ll be up for 11 hours and 39 minutes, setting at 7:21. The Moon, at last quarter today, will rise at 12:55 tomorrow morning.

Tomorrow night October 3rd at 7 p.m. I’ll be giving a talk at the main branch of the Traverse Area District Library on Woodmere Avenue, about the amazing discoveries made about Saturn, its rings and moons by the Cassini spacecraft and its Titan lander Huygens, spanning 7 years to get there and 13 orbiting Saturn among its rings and moons. The spacecraft made a planned plunge into Saturn’s atmosphere a year ago. The illustrated talk is called Remembering Cassini. Besides the numerical data sent back were images, some of which were made into videos, such as the landing of the Huygens probe on Titan. After the talk, if it will be clear, Saturn will be visible in the telescopes of the Grand Traverse Astronomical Society, along with other wonders of the skies.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Cassini and Huygens
Cassini and Huygens from Remembering Cassini

10/01/2018 – Ephemeris – Previewing October skies

October 1, 2018 Comments off

Ephemeris for Monday, October 1st. The Sun will rise at 7:40. It’ll be up for 11 hours and 42 minutes, setting at 7:23. The Moon, 1 day before last quarter, will rise at 11:55 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 26th. Venus has not been too noticeable in the evening for the last month, but in 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 times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


October Evening Star Chart

October evening star chart

Star Chart for October 2018 (10 p.m. EDT October 15, 2018). Created using my LookingUp program. Click on image to enlarge.

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. (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 9 p.m. and 6 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. 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.

October Morning Star Chart

October Morning Star Chart

Star Chart for October 2018 mornings based on 6 a.m. October 15th. Created using my LookingUp program. Click on image to enlarge.

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.
  • Follow the arc of the handle of the Big Dipper to the star Arcturus
  • The Summer Triangle is in red.
  • DracR on the evening star chart is the radiant for the Draconid meteor shwer which peaks on the 10th.
  • OriR on the morning star chart is the radiant of the Orionid meteor shower which peaks on the 21st.


      Time zone=EDT      
  Morning twilight Evening twilight Dark night Moon
Date Astronomical Nautical Nautical Astronomical Start End Illum.
2018-10-01 6h08m 6h42m 20h29m 21h03m 21h03m 23h56m 0.61
2018-10-02 6h09m 6h44m 20h27m 21h01m 21h01m 0.49
2018-10-03 6h11m 6h45m 20h25m 20h59m 20h59m 0h55m 0.37
2018-10-04 6h12m 6h46m 20h23m 20h57m 20h57m 2h02m 0.26
2018-10-05 6h13m 6h47m 20h22m 20h56m 20h56m 3h14m 0.16
2018-10-06 6h15m 6h49m 20h20m 20h54m 20h54m 4h28m 0.08
2018-10-07 6h16m 6h50m 20h18m 20h52m 20h52m 5h43m 0.03
2018-10-08 6h17m 6h51m 20h16m 20h50m 20h50m 6h17m 0
2018-10-09 6h18m 6h52m 20h14m 20h48m 20h48m 6h18m 0
2018-10-10 6h20m 6h53m 20h13m 20h46m 20h46m 6h20m 0.03
2018-10-11 6h21m 6h55m 20h11m 20h45m 20h56m 6h21m 0.08
2018-10-12 6h22m 6h56m 20h09m 20h43m 21h31m 6h22m 0.15
2018-10-13 6h23m 6h57m 20h07m 20h41m 22h11m 6h23m 0.24
2018-10-14 6h25m 6h58m 20h06m 20h39m 22h55m 6h25m 0.33
2018-10-15 6h26m 7h00m 20h04m 20h38m 23h44m 6h26m 0.43
2018-10-16 6h27m 7h01m 20h02m 20h36m 6h27m 0.52
2018-10-17 6h28m 7h02m 20h01m 20h35m 0h37m 6h28m 0.62
2018-10-18 6h30m 7h03m 19h59m 20h33m 1h33m 6h30m 0.71
2018-10-19 6h31m 7h04m 19h58m 20h31m 2h32m 6h31m 0.8
2018-10-20 6h32m 7h06m 19h56m 20h30m 3h32m 6h32m 0.87
2018-10-21 6h33m 7h07m 19h55m 20h28m 4h34m 6h33m 0.93
2018-10-22 6h34m 7h08m 19h53m 20h27m 5h37m 6h34m 0.93
2018-10-23 6h36m 7h09m 19h52m 20h25m 0.97
2018-10-24 6h37m 7h10m 19h50m 20h24m 1
2018-10-25 6h38m 7h12m 19h49m 20h22m 1
2018-10-26 6h39m 7h13m 19h47m 20h21m 0.97
2018-10-27 6h40m 7h14m 19h46m 20h19m 20h19m 21h01m 0.92
2018-10-28 6h42m 7h15m 19h44m 20h18m 20h18m 21h51m 0.85
2018-10-29 6h43m 7h17m 19h43m 20h17m 20h17m 22h48m 0.75
2018-10-30 6h44m 7h18m 19h42m 20h15m 20h15m 23h53m 0.64
2018-10-31 6h45m 7h19m 19h40m 20h14m 20h14m 0.53

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:

NASA Calendar of Planetary Events

Oct 01  Mo          Venus: 32.9° E
02 Tu 5:45 am Last Quarter
02 Tu 9:03 am Moon North Dec.: 21° N
03 We 11:10 pm Moon Ascending Node
04 Th 5:51 am Moon-Beehive: 1.3° N
05 Fr 5:58 pm Moon-Regulus: 1.9° S
05 Fr 6:29 pm Moon Perigee: 366400 km
08 Mo 11:47 pm New Moon
10 We 8:10 pm Draconid Shower: ZHR = 10
11 Th 5:21 pm Moon-Jupiter: 4.3° S
14 Su 11:01 pm Moon-Saturn: 2° S
15 Mo 1:26 pm Moon South Dec.: 21.2° S
15 Mo 10:32 pm Mercury-Venus: 6.2° N
16 Tu 2:02 pm First Quarter
17 We 8:03 am Moon Descending Node
17 We 3:16 pm Moon Apogee: 404200 km
18 Th 9:01 am Moon-Mars: 2.2° S
21 Su 1:03 pm Orionid Shower: ZHR = 20
23 Tu 8:43 pm Uranus Opposition
24 We 12:45 pm Full Moon
26 Fr 10:13 am Venus Inferior Conjunction with the Sun
27 Sa 9:04 am Moon-Aldebaran: 1.6° S
29 Mo 1:28 am Mercury-Jupiter: 3.1° N
29 Mo 1:34 am Moon North Dec.: 21.3° N
30 Tu 10:46 pm Moon Ascending Node
31 We 10:24 am Moon-Beehive: 1° N
31 We 11:40 am Last Quarter
31 We 3:05 pm Moon Perigee: 370200 km
Nov 01 Th Venus: 10.6° W

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),

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

Ephemeris of Sky Events for NMC Observatory
October, 2018 – Local time zone: EDT
Date Sun Twilight* Moon Illum
    Rise Set Hours End Start Phase R/S** Time Fractn
Mon 1 07:40a 07:22p 11:42 08:25p 06:37a   Rise 11:55p 55%
Tue 2 07:41a 07:21p 11:39 08:23p 06:38a L Qtr Rise 12:55a 43%
Wed 3 07:42a 07:19p 11:36 08:22p 06:39a   Rise 02:02a 32%
Thu 4 07:44a 07:17p 11:33 08:20p 06:41a   Rise 03:14a 22%
Fri 5 07:45a 07:15p 11:30 08:18p 06:42a   Rise 04:28a 13%
Sat 6 07:46a 07:13p 11:27 08:16p 06:43a   Rise 05:42a 6%
Sun 7 07:47a 07:12p 11:24 08:14p 06:44a   Rise 06:56a 2%
Mon 8 07:48a 07:10p 11:21 08:13p 06:46a New Set 07:24p 0%
Tue 9 07:50a 07:08p 11:18 08:11p 06:47a   Set 07:53p 1%
Wed 10 07:51a 07:06p 11:15 08:09p 06:48a   Set 08:23p 4%
Thu 11 07:52a 07:04p 11:12 08:07p 06:49a   Set 08:56p 10%
Fri 12 07:54a 07:03p 11:09 08:06p 06:50a   Set 09:31p 17%
Sat 13 07:55a 07:01p 11:06 08:04p 06:52a   Set 10:11p 25%
Sun 14 07:56a 06:59p 11:03 08:02p 06:53a   Set 10:55p 34%
Mon 15 07:57a 06:57p 11:00 08:01p 06:54a   Set 11:43p 43%
Tue 16 07:59a 06:56p 10:57 07:59p 06:55a F Qtr Set 12:36a 52%
Wed 17 08:00a 06:54p 10:54 07:57p 06:57a   Set 01:33a 62%
Thu 18 08:01a 06:52p 10:51 07:56p 06:58a   Set 02:31a 71%
Fri 19 08:02a 06:51p 10:48 07:54p 06:59a   Set 03:32a 79%
Sat 20 08:04a 06:49p 10:45 07:53p 07:00a   Set 04:34a 86%
Sun 21 08:05a 06:47p 10:42 07:51p 07:01a   Set 05:37a 92%
Mon 22 08:06a 06:46p 10:39 07:49p 07:03a   Set 06:41a 97%
Tue 23 08:08a 06:44p 10:36 07:48p 07:04a   Set 07:48a 99%
Wed 24 08:09a 06:43p 10:33 07:46p 07:05a Full Rise 07:13p 100%
Thu 25 08:10a 06:41p 10:30 07:45p 07:06a   Rise 07:44p 98%
Fri 26 08:12a 06:40p 10:27 07:44p 07:08a   Rise 08:19p 94%
Sat 27 08:13a 06:38p 10:25 07:42p 07:09a   Rise 09:01p 87%
Sun 28 08:14a 06:37p 10:22 07:41p 07:10a   Rise 09:51p 79%
Mon 29 08:16a 06:35p 10:19 07:40p 07:11a   Rise 10:48p 69%
Tue 30 08:17a 06:34p 10:16 07:38p 07:12a   Rise 11:53p 58%
Wed 31 08:18a 06:32p 10:13 07:37p 07:14a L Qtr Rise 01:02a 47%
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

09/28/2018 – Ephemeris – The GTAS will be at the Acme Fall Festival tomorrow

September 28, 2018 Comments off

Ephemeris for Friday, September 28th. The Sun will rise at 7:37. It’ll be up for 11 hours and 51 minutes, setting at 7:28. The Moon, half way from full to last quarter, will rise at 9:44 this evening.

The Grand Traverse Astronomical Society will be at the Acme Fall Festival tomorrow, that’s Saturday September 29th from 10 to 4 p.m. It will be held at Flintfields Horse Park on Bates Road, north of M72. The society members will bring their telescopes which will be used to view the Sun, and Venus if it’s clear. There will also be exhibits of astronomical photos from NASA, professional and our own amateur astronomers. As the festival and star party year winds down and the school year begins members of the society can bring astronomy and space to the classroom. Plus the society is beginning to plan for next year. Contact the Grand Traverse Astronomical Society via email at

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


09/27/2018 – Ephemeris – Twilight zone

September 27, 2018 Comments off

Ephemeris for Thursday, September 27th. The Sun will rise at 7:35. It’ll be up for 11 hours and 54 minutes, setting at 7:30. The Moon, 3 days past full, will rise at 9:12 this evening.

It will get dark tonight with the end of astronomical twilight at 9:11 p.m., and a minute later the bright Moon will rise spoiling the dark sky. Speaking of astronomical twilight there are three twilight periods: Civil, Nautical and Astronomical. In the evening civil twilight lasts from sunset to when the Sun drops to 6 degrees below the horizon. The scene around is still quite bright, but car headlights still need to be on. Nautical twilight lasts until the Sun is 12 degrees below the horizon. Bright stars and the horizon are visible for sextant use. After that is astronomical twilight until the Sun is 18 degrees below the horizon, when the stars become more and more numerous. After that it’s officially dark, Moon willing.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Twilight phases by
Twilight phases

More information about twilight, dusk and dawn can be found here:

09/25/2018 – Ephemeris – The harvest moon effect

September 25, 2018 Comments off

Ephemeris for Tuesday, September 25th. The Sun will rise at 7:33. It’ll be up for 12 hours and 1 minute, setting at 7:34. The Moon, 1 day past full, will rise at 8:17 this evening.

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 was officially yesterday. What the Moon around the Harvest Moon does do is rise only a little later each evening. This helped the farmers in earlier times extend daylight 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 27 minutes later than it will this evening.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Harvest moon effect 2018
The harvest moon effect 2018 showing the shallow path of the Moon near moonrise and the intervals between them for 5 consecutive dates. Created using Cartes du Ciel (Sky Charts).

09/24/2018 – Ephemeris – The harvest moon and the Chinese Mid-Autumn Festival

September 24, 2018 Comments off

Ephemeris for Monday, September 24th. The Sun will rise at 7:32. It’ll be up for 12 hours and 4 minutes, setting at 7:36. The Moon, at full today, will rise at 7:51 this evening.

Tonight at 10:53 p.m. the Moon will be full. And since it’s only two 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. I talked about the figure of a rabbit seen on the face of the Moon last Monday. He is a companion to Chang’e, and has a mortar on the Moon with him. He pounds out the medicine that makes the inhabitants of the sky immortal. The Chinese lunar probes are named Chang’e. Chang’e 3 landed on the Moon in 2013 and sent out a lunar rover named Yutu , the Jade Rabbit.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


The Jade Rabbit
The Jade Rabbit on the Moon. The more complete title is Jade Rabbit pounding medicine (in the mortar at his feet.
Chang'e flying to the Moon
Chang’e flying to the Moon. Unknown source.