10/02/2017 – Ephemeris – Looking ahead at October skies

Ephemeris for Monday, October 2nd. The Sun will rise at 7:41. It’ll be up for 11 hours and 38 minutes, setting at 7:20. The Moon, 3 days before full, will set at 5:04 tomorrow morning.

Let’s look at the skies for this month of October. The sun will still be moving south rapidly. Daylight hours in the Interlochen/Traverse City area will drop from 11 hours and 38 minutes today to 10 hours 13 minutes on the 31st. 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/Traverse City area. The Straits area will have the sun a degree lower. Local noon, when the sun is due south will be about 1:30 p.m. in Interlochen/Traverse City.

Later this month Jupiter will cross from the evening sky to the morning. Saturn will become lower in the southwest in the evening sky. And bits of Halley’s comet will return later in the month as the Orion meteor shower.

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

Addenda

October Evening Sky Chart

Star Chart for October 2017 (9 p.m. October 15, 2017). 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 and 45 minutes behind our daylight standard time meridian. during EST). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes (Daylight Time) or 45 minutes (Standard Time) earlier than the current time if you are near your time meridian.

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. 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 2017 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.
• Leaky Big Dipper drips on Leo.
• Follow the arc of the handle of the Big Dipper to the star Arcturus.
• The Summer Triangle is in red
• DraR is the Draconid meteor shower radiant.  Peaks on October 8th, but the Moon will interfere this year.
• OriR is the Orionid meteor shower radiant.  Peaks on October 21st with a zenithal hourly rate (ZHR) of 20

Twilight

Evening nautical twilight ends at 8:29 p.m. EDT on the 1st, decreasing to 7:40 p.m. EDT on the 31st.
Evening astronomical twilight ends at 9:03 p.m. EDT on the 1st, decreasing to 8:14 p.m. EDT on the 31st.
Morning astronomical twilight starts at 6:09 a.m. EDT on the 1st, and increasing to 6:07 a.m. EDT on the 31st.
Morning nautical twilight starts at 6:43 a.m. EDT on the 1st, and increasing to 6:42 a.m. EDT on the 31st.

NASA Calendar of Planetary Events

Oct 01  Su          Venus: 24.5° W
    01  Su 10:05 pm Moon Descending Node
    05  Th 12:15 pm Venus-Mars: 0.2° N
    05  Th  2:40 pm Full Moon (Harvest Moon)
    08  Su  4:33 pm Mercury Superior Conjunction with the Sun
    09  Mo  1:51 am Moon Perigee: 366,900 km
    09  Mo  2:05 pm Moon-Aldebaran: 0.6° S
    11  We  2:21 pm Moon North Dec.: 19.6° N
    12  Th  8:25 am Last Quarter
    13  Fr  4:29 pm Moon-Beehive: 3° N
    14  Sa  6:10 pm Moon Ascending Node
    15  Su  6:54 am Moon-Regulus: 0.2° S
    17  Tu  6:04 am Moon-Mars: 1.9° S
    17  Tu  8:21 pm Moon-Venus: 2.1° S
    19  Th  1:24 pm Uranus Opposition from the Sun
    19  Th  3:12 pm New Moon
    21  Sa  6:54 am Orionid Shower: ZHR = 20
    24  Tu  7:54 am Moon-Saturn: 3.6° S
    24  Tu 10:25 pm Moon Apogee: 405,200 km
    25  We  2:13 pm Moon South Dec.: 19.7° S
    26  Th  2:02 pm Jupiter Conjunction with the Sun
    27  Fr  6:22 pm First Quarter
    29  Su  2:41 pm Moon Descending Node
Nov 01  We          Venus: 16.8° 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

LU                  Ephemeris of Sky Events for Interlochen/TC
October, 2017    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun  1| 07:41a  07:22p  11:41 | 08:25p  06:38a |      Set  04:00a   84%|
|Mon  2| 07:42a  07:20p  11:38 | 08:23p  06:39a |      Set  05:05a   91%|
|Tue  3| 07:43a  07:19p  11:35 | 08:22p  06:40a |      Set  06:12a   96%|
|Wed  4| 07:44a  07:17p  11:32 | 08:20p  06:41a |      Set  07:21a   99%|
|Thu  5| 07:45a  07:15p  11:29 | 08:18p  06:42a |Full  Rise 07:38p  100%|
|Fri  6| 07:47a  07:13p  11:26 | 08:16p  06:44a |      Rise 08:10p   98%|
|Sat  7| 07:48a  07:11p  11:23 | 08:14p  06:45a |      Rise 08:45p   93%|
+------+-----------------------+----------------+-----------------------+
|Sun  8| 07:49a  07:10p  11:20 | 08:12p  06:46a |      Rise 09:25p   86%|
|Mon  9| 07:50a  07:08p  11:17 | 08:11p  06:47a |      Rise 10:09p   77%|
|Tue 10| 07:52a  07:06p  11:14 | 08:09p  06:49a |      Rise 11:01p   67%|
|Wed 11| 07:53a  07:04p  11:11 | 08:07p  06:50a |      Rise 11:59p   56%|
|Thu 12| 07:54a  07:02p  11:08 | 08:05p  06:51a |L Qtr Rise 01:02a   45%|
|Fri 13| 07:56a  07:01p  11:05 | 08:04p  06:52a |      Rise 02:08a   34%|
|Sat 14| 07:57a  06:59p  11:02 | 08:02p  06:54a |      Rise 03:16a   24%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 07:58a  06:57p  10:59 | 08:00p  06:55a |      Rise 04:23a   15%|
|Mon 16| 07:59a  06:56p  10:56 | 07:59p  06:56a |      Rise 05:30a    8%|
|Tue 17| 08:01a  06:54p  10:53 | 07:57p  06:57a |      Rise 06:35a    4%|
|Wed 18| 08:02a  06:52p  10:50 | 07:56p  06:58a |      Rise 07:39a    1%|
|Thu 19| 08:03a  06:50p  10:47 | 07:54p  07:00a |New   Set  07:14p    0%|
|Fri 20| 08:05a  06:49p  10:44 | 07:52p  07:01a |      Set  07:43p    2%|
|Sat 21| 08:06a  06:47p  10:41 | 07:51p  07:02a |      Set  08:14p    5%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 08:07a  06:46p  10:38 | 07:49p  07:03a |      Set  08:49p   10%|
|Mon 23| 08:09a  06:44p  10:35 | 07:48p  07:05a |      Set  09:27p   16%|
|Tue 24| 08:10a  06:42p  10:32 | 07:46p  07:06a |      Set  10:09p   24%|
|Wed 25| 08:11a  06:41p  10:29 | 07:45p  07:07a |      Set  10:56p   32%|
|Thu 26| 08:13a  06:39p  10:26 | 07:44p  07:08a |      Set  11:48p   41%|
|Fri 27| 08:14a  06:38p  10:23 | 07:42p  07:09a |F Qtr Set  12:44a   51%|
|Sat 28| 08:15a  06:36p  10:21 | 07:41p  07:11a |      Set  01:43a   60%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 08:17a  06:35p  10:18 | 07:39p  07:12a |      Set  02:45a   70%|
|Mon 30| 08:18a  06:33p  10:15 | 07:38p  07:13a |      Set  03:51a   79%|
|Tue 31| 08:19a  06:32p  10:12 | 07:37p  07:14a |      Set  04:58a   87%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise