Archive

Archive for June, 2017

06/30/2017 – Ephemeris – A look ahead at the month of July

June 30, 2017 1 comment

Ephemeris for Friday, June 30th. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:31, and it will rise tomorrow at 6:01. The Moon, at first quarter today, will set at 1:48 tomorrow morning.

Lets preview July’s skies. The sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 29 minutes tomorrow to 14 hours 40 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the sun at local noon, when the sun is due south will decrease from 68 degrees tomorrow to 63 degrees at month’s end. The sun will be a degree lower in the Straits area. Despite the warmth, the earth will reach its greatest distance from the sun late Monday. The planet Jupiter will descend lower and lower in the west as the month progresses.

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

Addenda

July Evening Star Chart

June Star Chart

Star Chart for July 2017 (11 p.m. July 15, 2017). Created using my LookingUp program. Click on image to enlarge.

The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 4:30 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 11 p.m. and 4:30 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.

July Morning Star Chart

Star Chart for June 2017 mornings

Star Chart for July 2017 mornings based on 4:30 a.m. July 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,
  • Then follow the Spike to Spica
  • The Summer Triangle is in red
  • DAqr is the Delta Aquariid Meteor Shower radiant

Evening nautical twilight ends at 11:00 p.m. EDT on the 1st, decreasing to 10:28 p.m. EDT on the 31st.
Evening astronomical twilight ends at 12:03 p.m. EDT on the 1st, decreasing to 11:17 p.m. EDT on the 31st.
Morning astronomical twilight starts at 3:41 a.m. EDT on the 1st, and increasing to 4:28 a.m. EDT on the 31st.
Morning nautical twilight starts at 4:41 a.m. EDT on the 1st, and increasing to 5:17 a.m. EDT on the 31st.

NASA Calendar of Planetary Events

Date        Time    Event
Jul 01  Sa          Venus: 43.7° W
    01  Sa  3:28 am Moon-Jupiter: 2.9° S
    03  Mo  8:59 pm Aphelion: 1.0167 AU
    04  Tu  8:21 pm Venus-Pleiades: 6.7° S
    06  Th 12:27 am Moon Apogee: 405900 km
    06  Th 11:34 pm Moon-Saturn: 3.6° S
    08  Sa  6:49 am Moon South Dec.: 19.4° S
    09  Su 12:07 am Full Moon
    09  Su  9:33 pm Mercury-Beehive: 0.1° N
    12  We  1:17 am Moon Descending Node
    13  Th  2:06 pm Venus-Aldebaran: 3.1° N
    16  Su  3:26 pm Last Quarter
    19  We  7:37 pm Moon-Aldebaran: 0.4° S
    20  Th  7:13 am Moon-Venus: 2.7° N
    21  Fr  1:09 pm Moon Perigee: 361200 km
    21  Fr  6:11 pm Moon North Dec.: 19.4° N
    23  Su  5:46 am New Moon
    24  Mo  8:47 pm Moon Ascending Node
    25  Tu  4:49 am Moon-Mercury: 0.9° S
    25  Tu  6:14 am Moon-Regulus: 0°
    25  Tu  1:07 pm Mercury-Regulus: 0.9° S
    26  We  7:59 pm Mars Conjunction
    27  Th 10:41 pm Delta Aquariid Meteor Shower: ZHR = 20
    28  Fr  4:15 pm Moon-Jupiter: 3.4° S
    29  Sa 11:59 pm Mercury Elongation: 27.2° E
    30  Su 11:23 am First Quarter
Aug 01  Tu       Venus: 38.4° 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.

July Rising and Setting Events

     LU                  Ephemeris of Sky Events for Interlochen/TC
July, 2017    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sat  1| 06:01a  09:32p  15:30 | 10:57p  04:35a |      Set  02:16a   60%|
+------+-----------------------+----------------+-----------------------+
|Sun  2| 06:01a  09:31p  15:29 | 10:56p  04:36a |      Set  02:44a   69%|
|Mon  3| 06:02a  09:31p  15:29 | 10:56p  04:37a |      Set  03:13a   77%|
|Tue  4| 06:03a  09:31p  15:28 | 10:55p  04:38a |      Set  03:46a   85%|
|Wed  5| 06:03a  09:30p  15:27 | 10:55p  04:39a |      Set  04:22a   91%|
|Thu  6| 06:04a  09:30p  15:26 | 10:54p  04:39a |      Set  05:02a   96%|
|Fri  7| 06:05a  09:30p  15:24 | 10:54p  04:40a |      Set  05:48a   99%|
|Sat  8| 06:05a  09:29p  15:23 | 10:53p  04:41a |      Set  06:38a  100%|
+------+-----------------------+----------------+-----------------------+
|Sun  9| 06:06a  09:29p  15:22 | 10:52p  04:43a |Full  Rise 09:45p   99%|
|Mon 10| 06:07a  09:28p  15:21 | 10:51p  04:44a |      Rise 10:25p   97%|
|Tue 11| 06:08a  09:28p  15:19 | 10:50p  04:45a |      Rise 11:00p   92%|
|Wed 12| 06:09a  09:27p  15:18 | 10:49p  04:46a |      Rise 11:32p   86%|
|Thu 13| 06:09a  09:26p  15:16 | 10:48p  04:47a |      Rise 12:03a   78%|
|Fri 14| 06:10a  09:26p  15:15 | 10:47p  04:48a |      Rise 12:32a   69%|
|Sat 15| 06:11a  09:25p  15:13 | 10:46p  04:49a |      Rise 01:02a   59%|
+------+-----------------------+----------------+-----------------------+
|Sun 16| 06:12a  09:24p  15:12 | 10:45p  04:51a |L Qtr Rise 01:33a   48%|
|Mon 17| 06:13a  09:23p  15:10 | 10:44p  04:52a |      Rise 02:08a   37%|
|Tue 18| 06:14a  09:23p  15:08 | 10:43p  04:53a |      Rise 02:47a   26%|
|Wed 19| 06:15a  09:22p  15:06 | 10:42p  04:55a |      Rise 03:33a   16%|
|Thu 20| 06:16a  09:21p  15:04 | 10:41p  04:56a |      Rise 04:26a    8%|
|Fri 21| 06:17a  09:20p  15:02 | 10:39p  04:57a |      Rise 05:28a    3%|
|Sat 22| 06:18a  09:19p  15:00 | 10:38p  04:59a |      Rise 06:35a    0%|
+------+-----------------------+----------------+-----------------------+
|Sun 23| 06:19a  09:18p  14:58 | 10:37p  05:00a |New   Set  09:31p    1%|
|Mon 24| 06:20a  09:17p  14:56 | 10:35p  05:01a |      Set  10:13p    3%|
|Tue 25| 06:21a  09:16p  14:54 | 10:34p  05:03a |      Set  10:49p    9%|
|Wed 26| 06:22a  09:15p  14:52 | 10:32p  05:04a |      Set  11:21p   16%|
|Thu 27| 06:23a  09:14p  14:50 | 10:31p  05:06a |      Set  11:50p   25%|
|Fri 28| 06:24a  09:13p  14:48 | 10:29p  05:07a |      Set  12:18a   34%|
|Sat 29| 06:25a  09:11p  14:45 | 10:28p  05:09a |      Set  12:46a   44%|
+------+-----------------------+----------------+-----------------------+
|Sun 30| 06:27a  09:10p  14:43 | 10:26p  05:10a |F Qtr Set  01:15a   53%|
|Mon 31| 06:28a  09:09p  14:41 | 10:25p  05:12a |      Set  01:47a   63%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

Above created using my LookingUp program for MS-DOS

Advertisements

06/29/2017 – Ephemeris – A closer look at the star Vega

June 29, 2017 1 comment

Ephemeris for Thursday, June 29th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:31, and it will rise tomorrow at 6:00. The Moon, 1 day before first quarter, will set at 1:21 tomorrow morning.

The bright star high in the east is Vega, one of the stars of the Summer Triangle an informal constellation called an asterism. Vega belongs to the official constellation Lyra the harp, which includes a narrow parallelogram of stars to its south. Vega is regarded by astronomers as a standard calibration star. Though a first magnitude star, its actual magnitude is 0.03. It is a type A0 pure white star, and is 27 light years away. Astronomers however got a shock in 1983 when calibrating the Infrared Astronomy Satellite (IRAS) on it: Vega showed an excess of Infrared radiation that means the star is orbited by a disk of dust, perhaps a Kuiper belt of its own. Due to the slow wobble of the earth’s axis Vega will be our pole star in 14 thousand years.

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

Addendum

Lyra

Magnified view of Lyra. Created using Stellarium.

Vega

Vega in the mid-infrared from the Spitzer Infrared Satellite. Credit: NASA/JPL-Caltech/University of Arizona.

Categories: Ephemeris Program, stars Tags: ,

06/28/2017 – Ephemeris – A last look at the bright planets for June 2017

June 28, 2017 1 comment

Ephemeris for Wednesday, June 28th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:31, and it will rise tomorrow at 6:00. The Moon, 2 days before first quarter, will set at 12:51 tomorrow morning.

Let’s take our weekly look at the bright planets for the last time in June. Jupiter is in the southwest as it gets dark in the evening, while the Moon is in the west. The bright blue-white star Spica, which pales in comparison to Jupiter, is seen left and below it. In even the smallest telescopes Jupiter’s four largest moons can be seen. They shift positions night from to night and sometimes even as you watch. Jupiter will set at 1:51 a.m. Saturn can now be seen in the evening as twilight fades in the southeast. It’s rings are spectacular in telescopes. It is to the left of the reddish star Antares, now more to the south. Brilliant Venus will rise at 3:31 a.m., at 5 a.m. it is seen in the east with Saturn about to set in the southwest.

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

Addendum

Evening planets

Jupiter, Saturn and the Moon at 10:30 p.m., June 28, 2017. Click on image to enlarge. Created using Stellarium.

Binocular Moon

The Moon as it would appear in binoculars at 10:30 p.m. June 28, 2017. Created using Stellarium.

Jupiter and its Moons

Jupiter and its four Galilean moons in tight to the planet as they might be seen in a telescope at 10:30 p.m,. June 28, 2017. Created using Cartes du Ciel (Sky Charts).

Project Pluto has the following events for the 28/29th:

Time is UT.  Events prior to 29 June 4:30 UT (12:30 a.m. EDT) will not be visible from Northern Michigan.  Data from Project Pluto:  https://www.projectpluto.com/jevent.htm#jun

I : Tra start: 28 Jun 2017 19:36
II : Occ start: 28 Jun 2017 20:39
I : Sha start: 28 Jun 2017 20:51
I : Tra end : 28 Jun 2017 21:47
I : Sha end : 28 Jun 2017 23:02
II : Occ end : 28 Jun 2017 23:07
II : Ecl start: 28 Jun 2017 23:11
III: Occ start: 28 Jun 2017 23:13
II : Ecl end : 29 Jun 2017 1:34
III: Occ end : 29 Jun 2017 1:46
III: Ecl start: 29 Jun 2017 4:30
III: Ecl end : 29 Jun 2017 6:43

Satellites:  I = Io, II = Europa, and III = Ganymede
Ecl = Eclipse (In Jupiter’s shadow), Occ = Occultation (Moon behind the planet).

Saturn and its moons

Saturn and its brightest moons overnight June 28/29, 2017. Created using Cartes du Ciel (Sky Charts).

Morning Planets

Venus and the setting Saturn at 5 a.m. June 29, 2017. Created using Stellarium. Click on the image to expand.

Telescopic Venus

Venus as it might be seen through a telescope at 5 a.m. June 29, 2017. This is displayed at a larger scale/magnification than the Jupiter or Saturn images above. Created using Stellarium.

Planets and Moon on a single night

Planets at sunset and sunrise of a single night starting with sunset on the right on June 28, 2017. The night ends on the left with sunrise on June 29. Click on the image to enlarge. Created using my LookingUp program.

06/27/2017 – Ephemeris – Arcturus as a look at the Sun’s future

June 27, 2017 1 comment

Ephemeris for Tuesday, June 27th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:31, and it will rise tomorrow at 5:59. The Moon, 3 days before first quarter, will set at 12:18 tomorrow morning.

With the Moon brightening the night sky, let’s take a look at the star Arcturus, which with its pointer, the curve of the Big Dipper’s handle is slipping into the high western sky. Arcturus is the 4th brightest night time star, though some think the star Vega, high in the east is brighter. They are different colors because Arcturus is orange, while Vega is whiter than the Sun. Arcturus is a preview of what the Sun will become in four or five billion years from now. It is only 10% more massive than the Sun and is that much older than the Sun, so it is turning into its red giant stage, after running out of hydrogen to turn into helium in its core to produce energy. The helium is now compressing and heating to begin its reaction.

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

Addendum

Arcturus finder chart

Arcturus finder chart with the Big Dipper and Vega as guide posts. Created using Stellarium.

Here’s one of my prior posts about Arcturus, about its great space velocity:  https://bobmoler.wordpress.com/2016/04/26/04262016-ephemeris-arcturus-just-passing-through/

06/26/2017 – Ephemeris – Latest sunset and the apparent positions of the Summer Triangle stars

June 26, 2017 1 comment

Ephemeris for Monday, June 26th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:31, and it will rise tomorrow at 5:59. The Moon, 3 days past new, will set at 11:40 this evening.

Tonight we have the latest sunset of the year. From now on until December sunsets will become earlier. Other than the sunrise and sunset numbers, we’ll begin to notice it for real in a few weeks. At first that realization strikes me a sad note that summer is beginning to end. However the astronomer in me realizes that means more night-time hours, and that the summer Milky Way is coming. Of the three bright stars of the Summer Triangle overhead and in the east, two of its stars are in the milky band. They are Deneb to the north and Altair to the south. Vega, closest to the zenith is not in the band. Actually all the stars we see with the naked eye or small telescopes belong to the Milky Way galaxy.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

The constellations Lyra, Cygnus and Aquila

Looking at the stars of the Summer Triangle and their location in and near the Milky Way band. Created using Stellarium.

06/23/2017 – Ephemeris – Astronomy events this weekend

June 23, 2017 1 comment

Ephemeris for Friday, June 23rd. Today the Sun will be up for 15 hours and 33 minutes, setting at 9:31, and it will rise tomorrow at 5:58. The Moon is new today, and won’t be visible.

Tomorrow afternoon and evening will be what we call a Sun & Star Party at the Sleeping Bear Dunes National Lakeshore. This event will be at the Dune Climb. From 4 to 6 p.m., the Sun will be featured using two types of telescopes, one showing the sun’s photosphere in what we call white light, and another showing the chromosphere above it in the light of hydrogen giving a completely different view. Starting at 9 p.m. will be a star party, actually really a planet party, viewing the planets Jupiter and Saturn, plus other objects visible in the deepening twilight.

Sunday at 11 a.m. to 4 p.m. members of the society will be in the parking lot of the NMC Laboratory on Aero Park Drive in Traverse City to view the Sun as part of the Michigan Clean Energy Conference and Fair.

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

Addendum

Viewing the transit

Kids viewing the Sun through the society’s Lunt hydrogen alpha solar telescope.

06/22/2017 – Ephemeris – Now that it’s summer, lets check out the Summer Triangle

June 22, 2017 1 comment

Ephemeris for Thursday, June 22nd. Today the Sun will be up for 15 hours and 33 minutes, setting at 9:31, and it will rise tomorrow at 5:57. The Moon, 1 day before new, will rise at 5:45 tomorrow morning.

We’re a day into summer, and the asterism or informal constellation called the Summer Triangle can be seen rising in the east as it gets dark. Highest of the three bright stars is Vega in the constellation Lyra the harp, whose body is seen in a narrow parallelogram nearby. The second star of the triangle is Deneb lower and left of Vega, It appears dimmer than Vega because it is by far the most distant of the three. The third star of the Summer Triangle is seen farther below and a right of Vega. It is Altair in Aquila the eagle, and the closest. Altair is 16.5 light years away, Vega is 27 light years while Deneb may be a whopping 2600 light years away. One light year is 6 trillion miles (9 trillion km).

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

Addendum

The Summer Triangle July 5, 2012 at 11 p.m. Created using Stellaruim and The Gimp.

The Summer Triangle. Created using Stellarium and The Gimp.