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10/01/2018 – Ephemeris – Previewing October skies
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.
Addendum
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

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.
Twilight
| 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: https://bobmoler.wordpress.com/2018/09/27/
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),
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
| 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
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 info@gtastro.org.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
09/27/2018 – Ephemeris – Twilight zone
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.
Addendum

More information about twilight, dusk and dawn can be found here: https://www.timeanddate.com/astronomy/different-types-twilight.html.
09/25/2018 – Ephemeris – The harvest moon effect
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.
Addendum

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



Chang’e 3 Lander on the Moon. Credit China National Space Administration 
Yutu Rover on the Moon. Credit China National Space Administration.
09/21/2018 – Ephemeris – Twilight talk and star, actually planet, party tonight in Thompsonville
Ephemeris for Friday, September 21st. The Sun will rise at 7:28. It’ll be up for 12 hours and 13 minutes, setting at 7:42. The Moon, 3 days before full, will set at 4:44 tomorrow morning.
Tonight members of the Grand Traverse Astronomical Society will hold a twilight talk and a star party at the Betsie Valley District Library in Thompsonville. It starts at 7 p.m. with a talk about how the Moon came to be and the features that will be visible tonight by yours truly. Where did the Moon come from? That mystery has baffled astronomers for ages. The rocks the Apollo astronauts brought back from the Moon offer clues to a possible answer. After which the Moon, Mars and Saturn will be visible. If cloudy, the talk will go on as scheduled, though the observing part of the evening will be replaced with a look at the skies via computer projection and a preview of the autumn season in the skies.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
09/20/2018 – Autumn will fall on us Saturday night
Ephemeris for Thursday, September 20th. The Sun will rise at 7:27. It’ll be up for 12 hours and 16 minutes, setting at 7:43. The Moon, half way from first quarter to full, will set at 3:44 tomorrow morning.
Welcome to the last few days of summer. The weather has stayed summery thus far through September. The Sun will reach the autumnal equinox point in the sky at 9:54 Saturday evening. At that moment the Sun will cross the celestial equator, a projection of the Earth’s equator, heading southward. All locations on the Earth except two will experience 12 hours of daylight and 12 hours of night. Well they would if the Earth didn’t have an atmosphere and sunset and sunrise were defined differently. The two locations that don’t experience equal night, which is what equinox means, are the north pole where the Sun will be setting and the south pole where the Sun will be rising. For us in the northern hemisphere daylight hours will be shorter and the Sun will peak lower in the south each day until the December solstice.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

09/19/2018 – Ephemeris – Wednesday is bright planet day on Ephemeris
Ephemeris for Talk Like a Pirate Day, Wednesday, September 19th. The Sun will rise at 7:26. It’ll be up for 12 hours and 19 minutes, setting at 7:45. The Moon, 3 days past first quarter, will set at 2:47 tomorrow morning.
Let’s look at the bright planets for this week. Four of them are visible in the evening sky. The brilliant Venus will be visible in the western twilight from about 8 p.m. until it sets at 8:40 p.m. Jupiter will be in the southwest as it gets dark. It is only outshone by Venus, and the Moon. The big planet will set at 9:40 p.m. Saturn will start the evening low in the southern sky and will stay relatively low, above the Teapot of Sagittarius. It will be due south at 7:59 p.m. and will set at 12:24 a.m. Mars will be low in the south-southeast as the skies darken tonight. and is now 49.5 million miles (79.7 million km) away. Mars will be due south at 10:09 p.m., and it will set at 2:27 a.m.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum



09/18/2018 – Ephemeris – Moon and planet party tomorrow night
Ephemeris for Tuesday, September 18th. The Sun will rise at 7:25. It’ll be up for 12 hours and 22 minutes, setting at 7:47. The Moon, 2 days past first quarter, will set at 1:53 tomorrow morning.
Tomorrow evening the Grand Traverse Astronomical Society will set up their telescopes at the Traverse Area District Library Central Library on Woodmere Avenue from 7 to 8:30 p.m. weather permitting for a star party, though it won’t actually feature stars. It will feature the Moon in its gibbous phase and the planets Jupiter, Saturn and Mars after 7:30 p.m. The evening will start with a twilight talk by yours truly about the Moon. Also Mars is showing some features now that it is still relatively close to the Earth at 49 and a half million miles away, and the global dust storm on the planet has subsided. On the face of Mars tomorrow night is the large formation Syrtis Major, sounds nice, but it means the Great Swamp.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
09/17/2018 – Ephemeris – The Moon Tonight and the Jade Rabbit
Ephemeris for Monday, September 17th. The Sun will rise at 7:24. It’ll be up for 12 hours and 25 minutes, setting at 7:49. The Moon, 1 day past first quarter, will set at 1:03 tomorrow morning.
Now is a good time to point that small telescope or binoculars toward the Moon. The gray seas on the right side of the moon depict the neck, head and ears of the Jade Rabbit. It’s curled up body is on the night side of the Moon to the left. The rabbit is upside down as we see him with the naked eye or binoculars. The Sea of Serenity is the upper part of his body, the head is the Sea of Tranquility. A bay south of Tranquility and the Sea of Nectar is one ear and the Sea of Fertility is the other ear. The Jade Rabbit is related to the Chinese Mid-Autumn Festival which occurs at our Harvest Moon. It’s on September 24th this year. Another amateur astronomer and myself brought telescopes to the local festival last year to view the Jade Rabbit on the Moon.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum




