01/06/2017 – Ephemeris – Telescope Clinic tonight at the NMC Observatory

January 6, 2017 Comments off

Ephemeris for Friday, January 6th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 59 minutes, setting at 5:18.  The Moon, 1 day past first quarter, will set at 2:34 tomorrow morning.

If you’ve received a telescope for Christmas and are having trouble setting it up, or have an unused one in a closet, basement or attic, bring them to Northwestern Michigan College’s Rogers Observatory tonight at 8 p.m.  The Grand Traverse Astronomical Society will be holding their annual telescope clinic to help you understand and use your telescope.  The clinic will extend through the period that will be set aside for a star party if it’s clear, to test the telescopes and show the owners how to use them.  Like anything telescopes take some time to learn how to use them and find celestial objects.  It took me 15 minutes to find Saturn with a telescope the first time I tried, and I knew where it was in the sky.  The observatory is south of Traverse City on Birmley Road.

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

In Memorium

Emmett Holmes

Emmett Holmes passed away last night (January 5th, 2017) after a long ordeal in attempting to have stem cells from his sister infused into his blood to rebuild his bone marrow. We at the Grand Traverse Astronomical Society knew him for a few short years, but in the time we benefited greatly from his expertise with telescopes and, helping out with star parties.. In the picture is his 13″ telescope with its distinctive tube that he built. Just recently he was elected to the Board of Directors of the Society.
We at the GTAS express our condolences to his wife Karen and the rest of his family. Emmett, rest in peace.

01/05/2017 – Ephemeris – About Ephemeris rise and set times, an annual confession

January 5, 2017 Comments off

Thursday, January 5th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 58 minutes, setting at 5:17.  The Moon, at first quarter today, will set at 1:23 tomorrow morning.

Lets talk about the Ephemeris program itself.  The format has changed little in the 41 ½ years it’s been on the air.  The problem with talking about rising and setting phenomenon is that back when I started IPR has only one transmitter and that was next to the studio  Now it has transmitters covering just about all of the northwestern part of the Lower Peninsula of Michigan.  So your rise and set time can be quite different.  On my Ephemeris website I have the times listed for the year for several locations in the IPR listening area under calendars.  On any search engine search for Bob Moler Ephemeris.  The Ephemeris Blog ( you’re already here) contains transcripts of the programs with illustrations and more in depth explanations.

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

Addendum

Bob Moler's Ephemeris main web page

Bob Moler’s Ephemeris main web page. http://ephemeris.bjmoler.org.

The red arrow points to the calendars for some locations, The green arrows point to program mp3s for the current week.  The blue arrows point to links to this blog.

Calendars currently available:

Cadillac
Interlochen/Traverse City (Source for the times on the Ephemeris program)
Ludington
Mackinaw City
Petoskey
Eagle Harbor – Keweenaw Peninsula
Houghton Lake
Earth’s Equator at the Prime Meridian (Just for fun. See how the daylight hours stay pretty much at 12 hours)

01/04/17 – Ephemeris – Saturn is poking its head up into the morning twilight

January 4, 2017 Comments off

Ephemeris for Wednesday, January 4th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 56 minutes, setting at 5:16.  The Moon, 1 day before first quarter, will set at 12:14 tomorrow morning.

Let’s take our first look at the bright planets for 2017.  Saturn can be glimpsed now in the morning, rising at 6:40 in the east-southeast.  Jupiter can be glimpsed even as the sky brightens.  It’s in the south at 7 a.m..  Jupiter will rise tomorrow at 1:29 a.m.  Venus and Mars are in the evening sky. At 6:30 p.m. these planets will be seen in the southwestern sky.  Venus is unmistakable as the brilliant evening star,  Mars will be above and left of it and much dimmer and will set at 10:13..  Venus will set at 9:15 p.m.  Venus is slowly heading northward for the rest of it’s evening appearance, and is moving higher in the sky, and is only 8 days from reaching it’s greatest eastern elongation or separation from the Sun.

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

Addendum

Evening planets

Venus, Mars and the Moon in the evening twilight of about an hour and three-quarters after sunset. 7 p.m. January 4, 2017. Created using Stellarium.

Telescopic Venus

Venus in a telescope at near half phase as it approaches its greatest apparent separation from the Sun, tonight January 4, 2017. Created using Stellarium.

Binocular Moon

The Moon as it might be seen tonight through binoculars, January 4, 2017. Created using Stellarium.

Morning planets

Jupiter in the south with Saturn peeking over the horizon in the southeast at 7 a.m. this morning, January 4, 2017. Created using Stellarium.

Jupiter and its moons

Jupiter and its moons this morning, January 4, 2017. Created using Stellarium.

Planets and Moon at sunset and sunrise of a single night

Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on January 4, 2017. The night ends on the left with sunrise on January 5. Click on image to enlarge. Created using my LookingUp program.

 

01/03/2017 – Ephemeris – The Earth will be closest to the Sun tomorrow

January 3, 2017 Comments off

Ephemeris for Tuesday, January 3rd.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 55 minutes, setting at 5:15.  The Moon, 2 days before first quarter, will set at 11:06 this evening.

The Earth has as elliptical orbit of the Sun, as do all planets.  It is close to circular but not quite.  The Earth’s distance from the Sun is 93 million miles (150 million km) plus or minus a million and a half miles.  Tomorrow at about 6 a.m. the Sun will be at a point called perihelion, only 91.4 million miles (147 million km).  It makes only a tiny difference in the Sun’s intensity, but since the Earth moves faster when closest to the Sun, it makes winter the shortest season at 89 days.  Aphelion, Earth’s farthest distance from the sun occurs around July 4th which makes summer the longest season at 93 days.  The eccentricity of an orbit can modify the seasons, but the seasons themselves are caused by the tilt of the planet’s axis alone.

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

Addendum

Earth's orbit

The Earth’s orbit, somewhat exaggerated, showing perihelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.

Categories: Ephemeris Program, Seasons Tags:

01/02/2017 – Ephemeris – Looking ahead at January 2017

January 2, 2017 Comments off

Ephemeris for Monday, January 2nd. 2017.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 54 minutes, setting at 5:14.  The Moon, 3 days before first quarter, will set at 10:00 this evening.

Let’s look ahead at the month of January. Today we will have out latest sunrise at 8:19.  That time will drop to 8:02 on the 31st.  Sunset times are already increasing, now at 5:14, will extend to 5:50 at month’s end, which will push the daylight hours to 9 hours 48 minutes by then.  The altitude of the Sun at local noon will increase from under 23 degrees today to 28 degrees at month’s end.  Tomorrow 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.  On Wednesday we will reach our closest distance from the Sun of the year at 91.3 million miles.

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

Addendum

January Star Charts

Evening
January evening star chart

Star Chart for January 2017 evenings. Created using my LookingUp program. Click on image to enlarge.

Morning
January Morning Star Chart

Star Chart for January 2017 mornings. Created using my LookingUp program. Click on image to enlarge.

Since the night time hours are long I’ve decided to add a morning star chart .

The planets and stars are plotted for the 15th at 9 p.m. EST, and again at 6 a.m.  Those are chart times.  Note, 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 1:45 or 0:45  earlier than the current time if you were near your time meridian.

Add a half hour to the chart time every week before the 15th and subtract a half hour for every week after the 15th.

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, and
  • Straighten to a spike to Spica
  • QuadR is the Radiant of the Quadrantid meteor shower

Evening nautical twilight ends at 6:22 p.m. EST on the 1st, increasing to 6:55 p.m. EST on the 31st.
Evening astronomical twilight ends at 6:57 p.m. EST on the 1st, increasing to 7:29 p.m. EST on the 31st.
Morning astronomical twilight starts at 6:35 a.m. EST on the 1st, and increasing to 6:23 a.m. EST on the 31st.
Morning nautical twilight starts at 7:10 a.m. EST on the 1st, and Increasing to 6:57 a.m. EST on the 31st.

NASA Calendar of Planetary Events

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

To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

Times are Eastern Time and follow the time change dates.

    Date   Time  Event
Jan 01  Su       Venus: 46.8° E
    02  Mo 04:20 Moon-Venus: 2° S
    02  Mo 13:14 Moon Descending Node
    03  Tu 01:47 Moon-Mars: 0.3° S
    03  Tu 09:10 Quadrantid Meteor Shower: ZHR = 120
    04  We 05:59 Perihelion: 0.9833 AU
    05  Th 14:47 First Quarter
    09  Mo 04:03 Mercury-Saturn: 6.7° N
    09  Mo 09:07 Moon-Aldebaran: 0.4° S
    10  Tu 01:07 Moon Perigee: 363200 km
    11  We 04:32 Moon North Dec.: 18.9° N
    12  Th 06:34 Full Moon
    12  Th 07:59 Venus Greatest Elongation: 47.1° East
    14  Sa 23:07 Moon-Regulus: 0.9° N
    15  Su 05:45 Moon Ascending Node
    19  Th 00:26 Moon-Jupiter: 3° S
    19  Th 04:59 Mercury Greatest Elongation: 24.1° West
    19  Th 17:14 Last Quarter
    21  Sa 19:14 Moon Apogee: 404900 km
    24  Tu 05:37 Moon-Saturn: 4° S
    25  We 06:59 Moon South Dec.: 18.9° S
    25  We 19:46 Moon-Mercury: 4° S
    27  Fr 19:07 New Moon
    29  Su 17:21 Moon Descending Node
    31  Tu 01:12 Jupiter-Spica: 3.5° N
    31  Tu 09:34 Moon-Venus: 4.2° N
    31  Tu 20:09 Moon-Mars: 2.4° N
Feb 01  We       Venus: 45.5° E

January 2017 Calendar

LU                  Ephemeris of Sky Events for Interlochen/TC
January, 2017    Local time zone: EST
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun  1| 08:20a  05:13p  08:53 | 06:23p  07:09a |      Set  08:55p   13%|
|Mon  2| 08:20a  05:14p  08:54 | 06:24p  07:09a |      Set  10:00p   21%|
|Tue  3| 08:20a  05:15p  08:55 | 06:25p  07:10a |      Set  11:06p   31%|
|Wed  4| 08:20a  05:16p  08:56 | 06:26p  07:10a |      Set  12:14a   41%|
|Thu  5| 08:19a  05:17p  08:57 | 06:27p  07:10a |F Qtr Set  01:24a   52%|
|Fri  6| 08:19a  05:18p  08:58 | 06:28p  07:09a |      Set  02:35a   63%|
|Sat  7| 08:19a  05:19p  08:59 | 06:29p  07:09a |      Set  03:47a   74%|
+------+-----------------------+----------------+-----------------------+
|Sun  8| 08:19a  05:20p  09:01 | 06:30p  07:09a |      Set  04:58a   83%|
|Mon  9| 08:19a  05:21p  09:02 | 06:31p  07:09a |      Set  06:07a   91%|
|Tue 10| 08:18a  05:22p  09:04 | 06:32p  07:09a |      Set  07:11a   97%|
|Wed 11| 08:18a  05:23p  09:05 | 06:33p  07:09a |      Set  08:07a  100%|
|Thu 12| 08:17a  05:25p  09:07 | 06:34p  07:08a |Full  Rise 06:04p  100%|
|Fri 13| 08:17a  05:26p  09:08 | 06:35p  07:08a |      Rise 07:12p   97%|
|Sat 14| 08:16a  05:27p  09:10 | 06:36p  07:08a |      Rise 08:20p   92%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 08:16a  05:28p  09:12 | 06:37p  07:07a |      Rise 09:26p   85%|
|Mon 16| 08:15a  05:30p  09:14 | 06:38p  07:07a |      Rise 10:31p   77%|
|Tue 17| 08:15a  05:31p  09:16 | 06:39p  07:06a |      Rise 11:33p   68%|
|Wed 18| 08:14a  05:32p  09:18 | 06:40p  07:06a |      Rise 12:33a   59%|
|Thu 19| 08:13a  05:33p  09:20 | 06:42p  07:05a |L Qtr Rise 01:32a   49%|
|Fri 20| 08:13a  05:35p  09:22 | 06:43p  07:05a |      Rise 02:30a   40%|
|Sat 21| 08:12a  05:36p  09:24 | 06:44p  07:04a |      Rise 03:27a   31%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 08:11a  05:37p  09:26 | 06:45p  07:03a |      Rise 04:23a   23%|
|Mon 23| 08:10a  05:39p  09:28 | 06:46p  07:03a |      Rise 05:18a   15%|
|Tue 24| 08:09a  05:40p  09:30 | 06:47p  07:02a |      Rise 06:09a    9%|
|Wed 25| 08:08a  05:42p  09:33 | 06:49p  07:01a |      Rise 06:57a    4%|
|Thu 26| 08:07a  05:43p  09:35 | 06:50p  07:00a |      Rise 07:41a    1%|
|Fri 27| 08:06a  05:44p  09:37 | 06:51p  07:00a |New   Set  05:43p    0%|
|Sat 28| 08:05a  05:46p  09:40 | 06:52p  06:59a |      Set  06:45p    1%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 08:04a  05:47p  09:42 | 06:54p  06:58a |      Set  07:51p    4%|
|Mon 30| 08:03a  05:49p  09:45 | 06:55p  06:57a |      Set  08:58p   10%|
|Tue 31| 08:02a  05:50p  09:47 | 06:56p  06:56a |      Set  10:06p   17%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

01/01/2017 – Happy Ephemeris New Year

January 1, 2017 Comments off

Since the month and year starts on a Sunday, and the Ephemeris program is not broadcast on the weekend I will give you some information that will be part of the January preview program that will run on Monday.

NASA Calendar of Planetary Events

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

To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

Times are Eastern Time and follow the time change dates.

    Date   Time  Event
Jan 01  Su       Venus: 46.8° E
    02  Mo 04:20 Moon-Venus: 2° S
    02  Mo 13:14 Moon Descending Node
    03  Tu 01:47 Moon-Mars: 0.3° S
    03  Tu 09:10 Quadrantid Meteor Shower: ZHR = 120
    04  We 05:59 Perihelion: 0.9833 AU
    05  Th 14:47 First Quarter
    09  Mo 04:03 Mercury-Saturn: 6.7° N
    09  Mo 09:07 Moon-Aldebaran: 0.4° S
    10  Tu 01:07 Moon Perigee: 363200 km
    11  We 04:32 Moon North Dec.: 18.9° N
    12  Th 06:34 Full Moon
    12  Th 07:59 Venus Greatest Elongation: 47.1° East
    14  Sa 23:07 Moon-Regulus: 0.9° N
    15  Su 05:45 Moon Ascending Node
    19  Th 00:26 Moon-Jupiter: 3° S
    19  Th 04:59 Mercury Greatest Elongation: 24.1° West
    19  Th 17:14 Last Quarter
    21  Sa 19:14 Moon Apogee: 404900 km
    24  Tu 05:37 Moon-Saturn: 4° S
    25  We 06:59 Moon South Dec.: 18.9° S
    25  We 19:46 Moon-Mercury: 4° S
    27  Fr 19:07 New Moon
    29  Su 17:21 Moon Descending Node
    31  Tu 01:12 Jupiter-Spica: 3.5° N
    31  Tu 09:34 Moon-Venus: 4.2° N
    31  Tu 20:09 Moon-Mars: 2.4° N
Feb 01  We       Venus: 45.5° E

January 2017 Calendar

LU                  Ephemeris of Sky Events for Interlochen/TC
January, 2017    Local time zone: EST
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun  1| 08:20a  05:13p  08:53 | 06:23p  07:09a |      Set  08:55p   13%|
|Mon  2| 08:20a  05:14p  08:54 | 06:24p  07:09a |      Set  10:00p   21%|
|Tue  3| 08:20a  05:15p  08:55 | 06:25p  07:10a |      Set  11:06p   31%|
|Wed  4| 08:20a  05:16p  08:56 | 06:26p  07:10a |      Set  12:14a   41%|
|Thu  5| 08:19a  05:17p  08:57 | 06:27p  07:10a |F Qtr Set  01:24a   52%|
|Fri  6| 08:19a  05:18p  08:58 | 06:28p  07:09a |      Set  02:35a   63%|
|Sat  7| 08:19a  05:19p  08:59 | 06:29p  07:09a |      Set  03:47a   74%|
+------+-----------------------+----------------+-----------------------+
|Sun  8| 08:19a  05:20p  09:01 | 06:30p  07:09a |      Set  04:58a   83%|
|Mon  9| 08:19a  05:21p  09:02 | 06:31p  07:09a |      Set  06:07a   91%|
|Tue 10| 08:18a  05:22p  09:04 | 06:32p  07:09a |      Set  07:11a   97%|
|Wed 11| 08:18a  05:23p  09:05 | 06:33p  07:09a |      Set  08:07a  100%|
|Thu 12| 08:17a  05:25p  09:07 | 06:34p  07:08a |Full  Rise 06:04p  100%|
|Fri 13| 08:17a  05:26p  09:08 | 06:35p  07:08a |      Rise 07:12p   97%|
|Sat 14| 08:16a  05:27p  09:10 | 06:36p  07:08a |      Rise 08:20p   92%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 08:16a  05:28p  09:12 | 06:37p  07:07a |      Rise 09:26p   85%|
|Mon 16| 08:15a  05:30p  09:14 | 06:38p  07:07a |      Rise 10:31p   77%|
|Tue 17| 08:15a  05:31p  09:16 | 06:39p  07:06a |      Rise 11:33p   68%|
|Wed 18| 08:14a  05:32p  09:18 | 06:40p  07:06a |      Rise 12:33a   59%|
|Thu 19| 08:13a  05:33p  09:20 | 06:42p  07:05a |L Qtr Rise 01:32a   49%|
|Fri 20| 08:13a  05:35p  09:22 | 06:43p  07:05a |      Rise 02:30a   40%|
|Sat 21| 08:12a  05:36p  09:24 | 06:44p  07:04a |      Rise 03:27a   31%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 08:11a  05:37p  09:26 | 06:45p  07:03a |      Rise 04:23a   23%|
|Mon 23| 08:10a  05:39p  09:28 | 06:46p  07:03a |      Rise 05:18a   15%|
|Tue 24| 08:09a  05:40p  09:30 | 06:47p  07:02a |      Rise 06:09a    9%|
|Wed 25| 08:08a  05:42p  09:33 | 06:49p  07:01a |      Rise 06:57a    4%|
|Thu 26| 08:07a  05:43p  09:35 | 06:50p  07:00a |      Rise 07:41a    1%|
|Fri 27| 08:06a  05:44p  09:37 | 06:51p  07:00a |New   Set  05:43p    0%|
|Sat 28| 08:05a  05:46p  09:40 | 06:52p  06:59a |      Set  06:45p    1%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 08:04a  05:47p  09:42 | 06:54p  06:58a |      Set  07:51p    4%|
|Mon 30| 08:03a  05:49p  09:45 | 06:55p  06:57a |      Set  08:58p   10%|
|Tue 31| 08:02a  05:50p  09:47 | 06:56p  06:56a |      Set  10:06p   17%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

12/31/2016 – Ephemeris year end

December 31, 2016 Comments off

No radio program today, being the weekend, so at the end of the calendar page below are the stats for today, the 31st.  This is the form of the calendar that I have on my Ephemeris website, which I update monthly.  It was created with the same data that the first portion of my program is generated from.  I have yearly calendars for 6 communities in the Interlochen Public Radio area in northwestern lower Michigan, and 1 in the U.P.  (That’s the Upper Peninsula, if you’re not from around here.)

You will have to hold off your New Years festivities for a bit tonight.  Not long, just one second.  Today, December 31st, 2016 will be 24 hours and 1 second long.  This “leap second” will be added as the 61st second of the minute 6:59 p.m. EST (23:59 UT).  The reason is that the Earth’s rotation is slowing down ever so slightly, compared to the atomic clocks at the Bureau of Time.  There is some discussion of eliminating this leap second.  Most scientists want to use a constant time stream, and don’t give a hang about the rotation of the Earth.  The positions of the Earth, Moon and the other planets would be incorrect if we used time strictly based on the Earth’s rotation.  Atomic time which is also affected by special and general relativity is used by GPS navigation satellites.  A one second jump in time, at our latitude (45° north) is equivalent of the earth’s rotation of about two tenths of a mile.  I hope everyone’s coordinated on this.

Ephemeris of Sky Events for Interlochen/TC

December, 2016 – Local time zone: EST
Date Sun Twilight* Moon Illum
Rise Set Hours End Start Phase R/S** Time Fractn
Thu 1 08:00a 05:03p 09:03 06:48p 06:15a Set 07:10p 6%
Fri 2 08:01a 05:03p 09:01 06:47p 06:16a Set 08:02p 11%
Sat 3 08:02a 05:02p 09:00 06:47p 06:17a Set 08:59p 18%
Sun 4 08:03a 05:02p 08:58 06:47p 06:18a Set 09:59p 26%
Mon 5 08:04a 05:02p 08:57 06:47p 06:19a Set 11:02p 36%
Tue 6 08:05a 05:02p 08:56 06:47p 06:20a Set 12:08a 46%
Wed 7 08:06a 05:02p 08:55 06:47p 06:21a F Qtr Set 01:16a 57%
Thu 8 08:07a 05:02p 08:54 06:47p 06:22a Set 02:26a 68%
Fri 9 08:08a 05:02p 08:53 06:47p 06:22a Set 03:39a 78%
Sat 10 08:09a 05:02p 08:52 06:47p 06:23a Set 04:53a 87%
Sun 11 08:10a 05:02p 08:51 06:48p 06:24a Set 06:08a 94%
Mon 12 08:11a 05:02p 08:51 06:48p 06:25a Set 07:21a 98%
Tue 13 08:12a 05:02p 08:50 06:48p 06:26a Full Rise 05:18p 100%
Wed 14 08:12a 05:02p 08:49 06:48p 06:26a Rise 06:17p 98%
Thu 15 08:13a 05:02p 08:49 06:49p 06:27a Rise 07:21p 94%
Fri 16 08:14a 05:03p 08:48 06:49p 06:28a Rise 08:28p 88%
Sat 17 08:14a 05:03p 08:48 06:49p 06:28a Rise 09:35p 80%
Sun 18 08:15a 05:03p 08:48 06:50p 06:29a Rise 10:41p 70%
Mon 19 08:16a 05:04p 08:48 06:50p 06:29a Rise 11:44p 61%
Tue 20 08:16a 05:04p 08:48 06:51p 06:30a L Qtr Rise 12:46a 51%
Wed 21 08:17a 05:05p 08:48 06:51p 06:30a Rise 01:46a 41%
Thu 22 08:17a 05:05p 08:48 06:52p 06:31a Rise 02:45a 32%
Fri 23 08:18a 05:06p 08:48 06:52p 06:31a Rise 03:43a 24%
Sat 24 08:18a 05:07p 08:48 06:53p 06:32a Rise 04:40a 16%
Sun 25 08:18a 05:07p 08:48 06:53p 06:32a Rise 05:37a 10%
Mon 26 08:19a 05:08p 08:49 06:54p 06:32a Rise 06:33a 5%
Tue 27 08:19a 05:09p 08:49 06:55p 06:33a Rise 07:26a 2%
Wed 28 08:19a 05:09p 08:50 06:55p 06:33a Rise 08:16a 0%
Thu 29 08:19a 05:10p 08:50 06:56p 06:33a New Set 05:57p 1%
Fri 30 08:19a 05:11p 08:51 06:57p 06:34a Set 06:53p 3%
Sat 31 08:20a 05:12p 08:52 06:58p 06:34a Set 07:52p 7%
* Astronomical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

The far right column of the table, the Moon’s illuminated fraction, may or may not appear in the calendar above depending on you browser or screen size.  It is correct on the Ephemeris website.

12/30/2016 – Ephemeris – Looking ahead at the eclipses of 2017

December 30, 2016 2 comments

Ephemeris for Friday, December 30th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 51 minutes, setting at 5:11.  The Moon, 1 day past new, will set at 6:53 this evening.

Looking ahead at astronomical events of the 2017.  There is one big one that all of us astronomers, both amateur and professional are looking forward to.  That is the total eclipse of the Sun on August 21st, where the center of the Moon’s shadow will sweep across the continental United States from Oregon to South Carolina.  The closest this path of totality will get to our area is around Carbondale, Illinois.  For the Grand Traverse area the Sun will be some 75% covered by the Moon.  As kind of a warm up event, we’ll have a slight eclipse of the Moon February 10th, where the Moon will enter the Earth’s outer partial shadow, nearly grazing the Earth’s inner shadow in the early evening.  It’s called a penumbral lunar eclipse.

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

Addendum

 

February 10, 2017 Penumbral Eclipse of the Moon

This is the maximum of the February 10th penumbral lunar eclipse. The Moon will appear to move diagonally down to the left. It is shown at maximum eclipse at 7:45 p.m. (0:45 UT February 11). Created using Cartes du Ciel.

Shadows are, of course, invisible unless they are cast on an object, so the Moon would appear alone, though the upper left part of it would be noticeably dimmer than the opposite side.

August 21, 2017 Total Solar Eclipse Path of Totality

A screen cap of the map showing the path of totality of the August 21, 2017 total solar eclipse from NASA’s eclipse page. Credit: NASA and Google Maps.  Click on image to enlarge.

Click here to go to the page where this interactive map is located.  The magenta marker with GD is the point with the greatest duration of totality of 2 minutes 40.2 seconds.  The green marker with GE denotes where the Moon’s umbral shadow is the widest.  Clicking on any point on the map will pop a balloon shows all the eclipse information for viewing it from that place.  The partial eclipse can be seen from all fifty states, though in Hawai’i the Sun rises with the eclipse in progress.

Here in the Grand Traverse Region, the Moon will encroach on about 8/10ths of the Sun’s diameter, covering 75% of the Sun’s face.

Maximum eclipse in Traverse City

What the maximum eclipse would look like with proper filtering at Traverse City, MI. Created using Stellarium.

Eclipse Times for Traverse City

Eclipse Starts 12:58:03 p.m.
Maximum Eclipse 2:20:15 p.m.
Eclipse Ends 3:40:51 p.m.
Magnitude of the eclipse 0.798
Obscuration of the Sun 75.1%

Solar Corona

This is an inkling of what a totally eclipsed Sun looks like. No photograph can do it justice. Ya gotta be there! The solar corona displayed during the July 10, 1972* total solar eclipse from Prince Edward Island. Credit Bob Moler.

* Update:  Thanks for the heads up on the typo: NationalEclipse.com.

Program Note:

I’ve developed a PowerPoint slide presentation highlighting my four total eclipses and a look at future eclipses.  I will be happy to give this presentation to school groups and organizations free of charge except for mileage reimbursement over 50 miles.  Contact me at bob@bjmoler.org.

December 31st – the longest day, really.

December 31st will be 24 hours and 1 second long.  This “leap second” will be added as the 61st second of the minute 6:59 p.m. EST (23:59 UT).  The reason is that the Earth’s rotation is slowing down ever so slightly, compared to the atomic clocks at the Bureau of Time.  There is some discussion of eliminating this leap second.  Most scientists want to use a constant time stream, and don’t give a hang about the rotation of the Earth.  The exact time which is also affected by special and general relativity is used by GPS navigation satellites.  A one second jump in time, at our latitude (45° north) is equivalent of the earth’s rotation of about two tenths of a mile.  I hope everyone’s coordinated on this.

12/29/2016 – Ephemeris – Astronomical milestones of 2016

December 29, 2016 Comments off

Ephemeris for Thursday, December 29th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 50 minutes, setting at 5:10.  The Moon is new today, and won’t be visible.

Looking back at 2016 the biggest astronomical news was the detection of gravitational waves coming from two separate collisions of black holes far beyond our Milky Way galaxy.  The two detectors in Washington state and in Louisiana recorded these events in September and December 2015, but the first announcement was made in February this year after the signals were cleaned up and studied.  The year saw the end of the European Space Agency’s Rosetta Mission to the comet we’ve come to call 67P after orbiting it for over two years.  The Opportunity and Curiosity rovers continued their exploration of Mars along with a fleet of satellites.  On a sad note, we lost pioneering Mercury astronaut John Glenn at the age of 95.

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

Addendum

Gravitational Waves Detected

The chirp heard ’round the world and indeed the universe. Credit: LIGO/Abbot et al. 2016. Hat tip: Phil Plait, the Bad Astronomer.

Rosetta, Final orbit

Rosetta, Final orbit. Credit & copyright European Space Agency (ESA)

 

12/28/2016 – Ephemeris – Our last weekly look at the bright planets for 2016

December 28, 2016 1 comment

Ephemeris for Wednesday, December 28th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 50 minutes, setting at 5:09.  The Moon, 1 day before new, will rise at 8:16 tomorrow morning.

Let’s take our last look at the bright planets for 2016.  In the southeast to south before 7:30 these mornings. Jupiter can be glimpsed as the sky brightens.  Jupiter will rise tomorrow at 1:53 a.m.  Venus and Mars are in the evening sky. At 6:30 p.m. these planets will be seen in the southwestern sky.  Venus is unmistakable as the brilliant evening star,  Mars will be above and left of it and much dimmer.  Venus will set at 9:01 p.m.  Mars will set at 10:12.  Mars’ setting time hasn’t changed much in the last 2 months.  Venus is slowly heading northward for the rest of it’s evening appearance, and is moving higher in the sky, and is closing in on it’s greatest eastern elongation from the Sun.

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

Addendum

Evening Planets

Venus and Mars in the evening twilight of about an hour and tree quarters after sunset. 7 p.m. December 28, 2016. Created using Stellarium.  Click on the image to enlarge.

Telescopic Venus

Venus as it might appear in a telescope at 7 p.m. December 28, 2016. It is 21.1′ (seconds or arc) in diameter. and 58% illuminated by the Sun.

Jupiter and the spring stars

Jupiter among a preview of the spring constellations at 7 a.m. now. Created using Stellarium. Click on the image to enlarge.

Jupiter and moons this morning.

Jupiter and its moons this morning, December 28, 2016 at 7 a.m. Note the compact grouping. Created using Cartes du Ciel (Sky Charts).

Jupiter and moons tomorrow morning.

Jupiter and its moons tomorrow morning, December 29, 2016 at 7 a.m. Note that Io is missing. It was eclipsed by Jupiter’s shadow on the west (right) side of the planet at 6:10 a.m. (11:10 UT). It will reappear from behind Jupiter on the other side at 14:33 UT for observers a few time zones west of here. Created using Cartes du Ciel (Sky Charts).

Planets and Moon at sunset and sunrise of a single night

Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on December 28, 2016. The night ends on the left with sunrise on December 29. Click on image to enlarge. Created using my LookingUp program.

Categories: Ephemeris Program, Planets Tags: , ,