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08/04/2017 – Ephemeris – View the Moon and planets Jupiter and Saturn tonight
Ephemeris for Friday, August 4th. The Sun rises at 6:32. It’ll be up for 14 hours and 30 minutes, setting at 9:03. The Moon, 3 days before full, will set at 4:32 tomorrow morning.
Tonight the Grand Traverse Astronomical Society will hold a viewing night at Northwestern Michigan College’s Rogers Observatory starting at 9 p.m. The celestial objects featured will be Jupiter, early, them the Moon and Saturn. Some of the brighter deep sky objects will be also seen as it gets dark. Deep sky objects are dim objects beyond the solar system like star clusters and nebulae, clouds of gas and dust either illuminated by stars or hiding them from view. The observatory’s telescopes are augmented by telescopes set up by members of the society. We also welcome the public to bring their telescopes to learn how to use them. The observatory is located south of Traverse City on Birmley Road.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
08/03/2017 – Ephemeris – The surreal world of totality
Ephemeris for Thursday, August 3rd. The Sun rises at 6:31. It’ll be up for 14 hours and 33 minutes, setting at 9:04. The Moon, half way from first quarter to full, will set at 3:43 tomorrow morning.
The brief world of solar eclipse totality is one everyone should experience at least once in their lifetime. The duration of totality is so brief that one cannot really absorb it all. As the Moon covers the last of the Sun’s bright photosphere there is a chill as the Sun’s heat is extinguished. Darkness of a deep twilight descends. Street lights come on, cocks will crow, as animals take the darkness as the approach of night. The approaching shadow of the Moon can be seen. During totality the Sun’s corona can be seen as a silvery apparition around the black spot of the Moon that’s covering the Sun’s disk. Bright planets and some stars will appear in a surreal image in the darkened sky, but the horizon is bright. Then suddenly the diamond ring appears and it’s over.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Screen capture from a video of a total solar eclipse of November 2, 2013 at the small village of Mikongo in the equatorial African country of Gabon. This video shows the eclipse expedition of Williams College led by Professor Jay Pasachoff. © 2013 Michael Zeiler. See the video at https://www.greatamericaneclipse.com/splendor/.
Check out the Great American Eclipse web site.
An animation of Stellarium’s version of the sky during totality of the August 21, 2017. My personal caveats based on 4 total eclipses are that Venus is always visible, Mercury only sometimes. I’ve never seen a star. Also the Sun’s corona is a whole lot brighter than seen here. See the image above. Click on this image to enlarge.
Diamond ring at the end of totality of the total solar eclipse July 10, 1972. Credit Bob Moler.
Additional notes:
The Sun’s corona is perfectly safe to view without a solar filter. Actually the Sun will disappear in solar eclipse glasses and projection viewers. That’s the time to look at the Sun with the naked eye or binoculars. However, when the corona brightens around the right side of the Moon, and the red chromosphere appears, drop the binoculars for the bright diamond ring will quickly appear.
The corona for the quiet Sun stretches out on either side of the Sun, with little at the poles. The active Sun, near a sunspot peak, tends to have a roundish corona. Below is the corona last evening via the Solar and Heliospheric Observatory (SOHO).
The black disk on the stalk is the occulting disk, hiding the bright photosphere and producing an artificial eclipse.. The white circle is the size of the Sun’s disk. Credit ESA and NASA
Part of the inner corona close to the Sun is covered by the disk. That is what is easiest to see during a total solar eclipse.
For a couple of minutes just before totality starts and again after it ends strange bands of light and shadow will flit along the smooth surface of the ground. They’re called shadow bands. I’ve seen the effect on a large concrete parking lot, an airport tarmac and a softball infield. The nearest thing I’ve seen to it the shadow ripples on the bottom of a swing pool on a sunny day. I finally saw them on my fourth total solar eclipse and two subsequent annular eclipses* which were viewed from or near smooth surfaces. It’s a product of air turbulence and shows up at night in the twinkling of stars.
* An annular eclipse is one in which the Moon is too far, and thus too small to completely cover the face of the Sun. The central part of this type of eclipse leaves a ring or annulus of the bright Sun surrounding the Moon.
08/02/2017 – Ephemeris – Lets check in on the bright planets for this week
Ephemeris for Wednesday, August 2nd. The Sun rises at 6:30. It’ll be up for 14 hours and 35 minutes, setting at 9:06. The Moon, 3 days past first quarter, will set at 3:00 tomorrow morning.
Let’s take our weekly look at the bright planets. Jupiter is sinking in the west-southwest as it gets dark in the evening. The bright blue-white star Spica, which pales in comparison to Jupiter, is seen left of it. In even the smallest telescopes Jupiter’s four largest moons can be seen. They shift positions from night to night. Jupiter will set at 11:41 p.m. Saturn can now be seen in the south as evening as twilight fades. Tonight Saturn will be just below and left of the waxing gibbous Moon. The reddish star Antares is off to the right of Saturn. Saturn’s rings are spectacular in telescopes. Saturn will set at 2:48 a.m. In the morning sky, brilliant Venus will rise at 3:29 a.m. and be visible until about 6 tomorrow morning. Mars and Mercury are too close to the Sun for us to see now.
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 p.m., August 2, 2017. Created using Stellarium. Click on image to enlarge.
The Moon and Saturn at 10 p.m. EDT August 2, 2017. The Moon is moving to the left (eastward) at about its diameter every hour, so observers at different longitudes will see it in a different position depending on their time zone. Created using Stellarium.
Jupiter and its moons at 10 p.m. August 2, 2017. Created using Cartes du Ciel (Sky Charts).
Saturn and its brightest moons overnight August 2/3, 2017. Created using Cartes du Ciel (Sky Charts).
Venus with Orion rising at 5:30 a.m. August 3, 2017. Created using Stellarium.
Venus in a telescope on the morning of August 3, 2017. It is greatly enlarged here to show its phase. Created using Stellarium
Planets at sunset and sunrise of a single night starting with sunset on the right on August 2, 2017. The night ends on the left with sunrise on August 3. Click on the image to enlarge. Created using my LookingUp program.
08/01/2017 – Ephemeris – A look at the busy month of August in astronomy
Ephemeris for Tuesday, August 1st. The Sun rises at 6:29. It’ll be up for 14 hours and 38 minutes, setting at 9:07. The Moon, 2 days past first quarter, will set at 2:21 tomorrow morning.
Let’s look ahead at the month of August in the skies. Daylight hours will decrease from 14 hours and 38 minutes today to 13 hours 16 minutes on the 31st. The altitude of the sun at local noon, that is degrees of angle above the horizon will decrease from 63 degrees today to just over 53 degrees on the 31st. The Perseid meteor shower will reach its peak on the evening of the 12th. However the bright waning gibbous moon will rise just after 11:30 for a very short dark sky viewing period. The big event this month will be the total solar eclipse that will be visible from all 50 of the United States and total for a narrow strip of land stretching from Oregon to South Carolina. That will occur on the afternoon of Monday the 21st.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
August Evening Star Chart
Star Chart for August 2017 (10 p.m. August 15, 2017). Created using my LookingUp program. Click on image to enlarge.
The planets and stars are plotted for the 15th at 10 p.m. EDT in the evening and 5 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 10 p.m. and 5 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.
August Morning Star Chart
Star Chart for August 2017 mornings based on 5 a.m. August 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
- PerR is the Perseid Meteor Shower radiant
Evening nautical twilight ends at 10:26 p.m. EDT on the 1st, decreasing to 9:30 p.m. EDT on the 31st.
Evening astronomical twilight ends at 11:15 p.m. EDT on the 1st, decreasing to 10:09 p.m. EDT on the 31st.
Morning astronomical twilight starts at 4:30 a.m. EDT on the 1st, and increasing to 5:24 a.m. EDT on the 31st.
Morning nautical twilight starts at 5:19 a.m. EDT on the 1st, and increasing to 6:03 a.m. EDT on the 31st.
NASA Calendar of Planetary Events
Date Time Event
Aug 01 Tu Venus: 38.4° W
02 We 1:55 pm Moon Apogee: 405000 km
03 Th 3:31 am Moon-Saturn: 3.8° S
04 Fr 2:17 pm Moon South Dec.: 19.4° S
07 Mo 2:11 pm Full Moon
07 Mo 2:22 pm Partial Lunar Eclipse (Not visible from here)
08 Tu 6:56 am Moon Descending Node
12 Sa 2:35 pm Perseid Shower: ZHR = 90
14 Mo 9:15 pm Last Quarter
16 We 2:39 am Moon-Aldebaran: 0.4° S
18 Fr 2:50 am Moon North Dec.: 19.4° N
18 Fr 9:14 am Moon Perigee: 366100 km
19 Sa 12:45 am Moon-Venus: 2.3° N
20 Su 3:15 am Moon-Beehive: 3.2° N
21 Mo 6:34 am Moon Ascending Node
21 Mo 2:26 pm Total Solar Eclipse
21 Mo 2:30 pm New Moon
25 Fr 9:00 am Moon-Jupiter: 3.7° S
26 Sa 4:32 pm Mercury Inferior Conj.
29 Tu 4:13 am First Quarter
30 We 7:25 am Moon Apogee: 404300 km
30 We 10:23 am Moon-Saturn: 3.9° S
31 Th 10:03 pm Moon South Dec.: 19.4° S
Sep 01 Fr Venus: 31.7° 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.
August Rising and Setting Events
LU Ephemeris of Sky Events for Interlochen/TC August, 2017 Local time zone: EDT +-----------------------------------------------------------------------+ | DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM | | | RISE SET HOURS | END START |PHASE SET** TIME FRACTN| +=======================================================================+ |Tue 1| 06:29a 09:08p 14:38 | 10:23p 05:13a | Set 02:21a 72%| |Wed 2| 06:30a 09:06p 14:36 | 10:21p 05:15a | Set 03:00a 80%| |Thu 3| 06:31a 09:05p 14:34 | 10:20p 05:16a | Set 03:43a 87%| |Fri 4| 06:32a 09:04p 14:31 | 10:18p 05:18a | Set 04:32a 93%| |Sat 5| 06:33a 09:02p 14:29 | 10:16p 05:19a | Set 05:26a 97%| +------+-----------------------+----------------+-----------------------+ |Sun 6| 06:34a 09:01p 14:26 | 10:15p 05:21a | Set 06:24a 99%| |Mon 7| 06:36a 09:00p 14:23 | 10:13p 05:22a |Full Rise 09:01p 100%| |Tue 8| 06:37a 08:58p 14:21 | 10:11p 05:24a | Rise 09:35p 98%| |Wed 9| 06:38a 08:57p 14:18 | 10:09p 05:25a | Rise 10:06p 95%| |Thu 10| 06:39a 08:55p 14:16 | 10:07p 05:27a | Rise 10:36p 89%| |Fri 11| 06:40a 08:54p 14:13 | 10:06p 05:28a | Rise 11:06p 81%| |Sat 12| 06:41a 08:52p 14:10 | 10:04p 05:30a | Rise 11:36p 72%| +------+-----------------------+----------------+-----------------------+ |Sun 13| 06:43a 08:51p 14:08 | 10:02p 05:31a | Rise 12:09a 62%| |Mon 14| 06:44a 08:49p 14:05 | 10:00p 05:33a |L Qtr Rise 12:46a 51%| |Tue 15| 06:45a 08:48p 14:02 | 09:58p 05:34a | Rise 01:28a 39%| |Wed 16| 06:46a 08:46p 13:59 | 09:56p 05:36a | Rise 02:16a 28%| |Thu 17| 06:47a 08:44p 13:57 | 09:54p 05:37a | Rise 03:13a 18%| |Fri 18| 06:49a 08:43p 13:54 | 09:52p 05:39a | Rise 04:16a 10%| |Sat 19| 06:50a 08:41p 13:51 | 09:50p 05:40a | Rise 05:24a 4%| +------+-----------------------+----------------+-----------------------+ |Sun 20| 06:51a 08:39p 13:48 | 09:48p 05:42a | Rise 06:35a 1%| |Mon 21| 06:52a 08:38p 13:45 | 09:47p 05:43a |New Set 08:44p 0%| |Tue 22| 06:53a 08:36p 13:42 | 09:45p 05:44a | Set 09:18p 2%| |Wed 23| 06:54a 08:34p 13:39 | 09:43p 05:46a | Set 09:49p 6%| |Thu 24| 06:56a 08:33p 13:37 | 09:41p 05:47a | Set 10:18p 12%| |Fri 25| 06:57a 08:31p 13:34 | 09:39p 05:49a | Set 10:46p 20%| |Sat 26| 06:58a 08:29p 13:31 | 09:37p 05:50a | Set 11:15p 28%| +------+-----------------------+----------------+-----------------------+ |Sun 27| 06:59a 08:27p 13:28 | 09:35p 05:52a | Set 11:46p 37%| |Mon 28| 07:00a 08:26p 13:25 | 09:33p 05:53a | Set 12:19a 47%| |Tue 29| 07:01a 08:24p 13:22 | 09:31p 05:54a |F Qtr Set 12:56a 56%| |Wed 30| 07:03a 08:22p 13:19 | 09:29p 05:56a | Set 01:38a 65%| |Thu 31| 07:04a 08:20p 13:16 | 09:27p 05:57a | Set 02:24a 74%| +-----------------------------------------------------------------------+ * Nautical Twilight ** Moonrise or moonset, whichever occurs between sunset and sunrise
Bob Moler's Ephemeris Blog 