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06/30/2017 – Ephemeris – A look ahead at the month of July
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
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 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
06/29/2017 – Ephemeris – A closer look at the star Vega
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
Magnified view of Lyra. Created using Stellarium.
Vega in the mid-infrared from the Spitzer Infrared Satellite. Credit: NASA/JPL-Caltech/University of Arizona.
06/28/2017 – Ephemeris – A last look at the bright planets for June 2017
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
Jupiter, Saturn and the Moon at 10:30 p.m., June 28, 2017. Click on image to enlarge. Created using Stellarium.
The Moon as it would appear in binoculars at 10:30 p.m. June 28, 2017. Created using Stellarium.
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 brightest moons overnight June 28/29, 2017. Created using Cartes du Ciel (Sky Charts).
Venus and the setting Saturn at 5 a.m. June 29, 2017. Created using Stellarium. Click on the image to expand.
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 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
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 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
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
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
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
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
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. Created using Stellarium and The Gimp.
06/21/2017 – Ephemeris – Checking out the bright planets on the first day of summer
Ephemeris for Wednesday, June 21st. 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, 2 days before new, will rise at 4:54 tomorrow morning.
Let’s take our weekly look at the bright planets on this first day of summer. Dominating the evening sky now is Jupiter in the southwest. The bright blue-white star Spica, which pales in comparison to it, 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 2:18 a.m. Saturn can now be seen in the evening as twilight fades in the southeast. It is now officially an evening planet after opposition last week. At 5 a.m. both Saturn and Venus will be seen in the morning twilight. Brilliant Venus will be low in the east tomorrow morning after rising at 3:37 a.m.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn and the southern evening constellations at 10:30 p.m., June 21, 2017. Click on the image to enlarge. Created using Stellarium.
Jupiter and its four Galilean moons as they might be seen in a telescope at 10:30 p.m,. June 21, 2017. Created using Cartes du Ciel (Sky Charts).
Saturn and its brightest moons overnight June 21/22, 2017. Created using Cartes du Ciel (Sky Charts).
Saturn, Venus and the rising crescent Moon at 5 a.m. June 22, 2017. Click on the image to enlarge. Created using Stellarium. Click on the image to expand.
Venus as it might be seen through a telescope at 5 a.m. June 22, 2017. This is displayed at a larger scale/magnification than the Jupiter or Saturn images above. Created using Stellarium.
The skinny crescent moon as it might be seen in binoculars, after 5 a.m., June 22, 2017. Created using Stellarium.
Planets at sunset and sunrise of a single night starting with sunset on the right on June 21, 2017. The night ends on the left with sunrise on June 22. Click on the image to enlarge. Created using my LookingUp program.
06/20/2017 – Ephemeris – Summer will begin overnight tonight
Ephemeris for Tuesday, June 20th. 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, half way from last quarter to new, will rise at 4:11 tomorrow morning.
Summer will begin overnight at 12:25 a.m. (4:25 UT June 21, 2017) The sun will at its highest at noon today and tomorrow, well at local solar noon that is, which is 1:44 p.m. in the Interlochen Traverse City area. At that time the Sun will reach an altitude or angle above the southern horizon of nearly 69 degrees. If you want to get an idea of the difference between that and the Sun at the winter solstice, check out Saturn tonight. It is almost to the point in the sky where the Sun was at the winter solstice. Notice how low it is in the sky, and how few hours it is up. The cause is the tilt of the earth’s axis of 23 and a half degrees. It gives us a 47 degree span of altitudes of the sun over the year. It is not the sun’s distance that causes seasons, as we’ll see next month.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Sun’s path through the sky on the summer solstice day from Traverse City, MI. Created using my LookingUp program.
Earth from the DSCOVR satellite at the June solstice 2015. Credit NOAA
06/19/2017 – Ephemeris – The hero Hercules in the stars
Ephemeris for Monday, June 19th. Today the Sun will be up for 15 hours and 33 minutes, setting at 9:30, and it will rise tomorrow at 5:57. The Moon, 2 days past last quarter, will rise at 3:33 tomorrow morning.
The greatest Greek hero of all, Hercules, gets a dim group of stars on the border between the spring and summer stars. At 11 p.m. Hercules is high in the eastern sky. It is located above and right of the bright star, Vega, also in the east. Hercules’ central feature is a keystone shaped box of stars, called the Keystone, which represents the old boy’s shorts. From each top corner extend lines of stars that are his legs, from the bottom stars, the rest of his torso and arms extend. So in one final indignity he’s upside down in our sky. Just below and right of the topmost star of the keystone is what looks like a fuzzy star in binoculars or small telescope. It is the Great Hercules Globular Star Cluster, also known as M13, home to a million stars.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Hercules animation showing neighboring stars, constellation outlines, deep sky objects, and constellation art for Hercules. Created using Stellarium. Click on image to enlarge.
M13, the Great Globular Star Cluster in Hercules. Credit: Scott Anttila
Bob Moler's Ephemeris Blog 