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Archive for March, 2020

03/31/2020 – Ephemeris – Looking ahead at April skies

March 31, 2020 Comments off

Ephemeris for Tuesday, March 31st. Today the Sun will be up for 12 hours and 45 minutes, setting at 8:09, and it will rise tomorrow at 7:22. The Moon, 1 day before first quarter, will set at 3:30 tomorrow morning.

The 4th month of the year begins tomorrow. Daylight hours in the Interlochen/Traverse City area and will increase from 12 hours and 48 minutes tomorrow to 14 hours 13 minutes on the 30th. The altitude, or angle, of the Sun above the southern horizon at local noon will be 50 degrees tomorrow and will ascend to 60 degrees on the 30th. The altitude of the Sun in the Straits area will be a degree lower. The actual time of local apparent noon this month for the Interlochen/Traverse City area, when the Sun passes due south, will be about 1:43 p.m. Venus is our brilliant evening planet while Jupiter, Saturn and Mars are our morning planets with Mars passing below Saturn unseen by us this afternoon.

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

Addendum

March Evening Star Chart

April Evening Star Chart

Star Chart for April 2020 (10 p.m. EDT April 15, 2020). Click on image to enlarge. Created using my LookingUp program.

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. The brilliant planet Venus is our Evening Star in the West at chart time. Note that Traverse City is located approximately 45 minutes behind our time meridian, West 75° longitude. (An hour and 45 minutes behind our daylight saving time meridian during EDT).

April Morning Star Chart

April Morning Star Chart

Star Chart for April mornings 2020 (5 a.m. EDT April 15, 2020). Click on image to enlarge. Created using my LookingUp program.

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.
  • The leaky bowl of the 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 appears in red.
  • LyrR is the radiant of the Lyrid meteor shower which will reach peak on the morning of the 22nd.

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning twilight Evening twilight Dark night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2020-04-01 5h45m 6h22m 21h18m 21h55m 3h31m 5h45m 0.56
2020-04-02 5h43m 6h20m 21h19m 21h56m 4h24m 5h43m 0.67
2020-04-03 5h41m 6h18m 21h21m 21h58m 5h09m 5h41m 0.78
2020-04-04 5h39m 6h16m 21h22m 21h59m 0.87
2020-04-05 5h37m 6h14m 21h24m 22h01m 0.87
2020-04-06 5h35m 6h12m 21h25m 22h03m 0.94
2020-04-07 5h32m 6h10m 21h26m 22h04m 0.99
2020-04-08 5h30m 6h08m 21h28m 22h06m 1
2020-04-09 5h28m 6h06m 21h29m 22h08m 22h08m 22h36m 0.98
2020-04-10 5h26m 6h04m 21h31m 22h09m 22h09m 23h54m 0.93
2020-04-11 5h24m 6h02m 21h32m 22h11m 22h11m 0.85
2020-04-12 5h21m 6h00m 21h34m 22h13m 22h13m 1h07m 0.76
2020-04-13 5h19m 5h58m 21h35m 22h14m 22h14m 2h13m 0.66
2020-04-14 5h17m 5h56m 21h37m 22h16m 22h16m 3h09m 0.55
2020-04-15 5h15m 5h54m 21h38m 22h18m 22h18m 3h56m 0.44
2020-04-16 5h12m 5h52m 21h40m 22h20m 22h20m 4h34m 0.34
2020-04-17 5h10m 5h50m 21h41m 22h21m 22h21m 5h05m 0.25
2020-04-18 5h08m 5h48m 21h43m 22h23m 22h23m 5h08m 0.17
2020-04-19 5h06m 5h46m 21h44m 22h25m 22h25m 5h06m 0.11
2020-04-20 5h04m 5h44m 21h46m 22h27m 22h27m 5h04m 0.05
2020-04-21 5h01m 5h43m 21h47m 22h29m 22h29m 5h01m 0.02
2020-04-22 4h59m 5h41m 21h49m 22h30m 22h30m 4h59m 0
2020-04-23 4h57m 5h39m 21h50m 22h32m 22h32m 4h57m 0
2020-04-24 4h55m 5h37m 21h52m 22h34m 22h34m 4h55m 0.03
2020-04-25 4h52m 5h35m 21h53m 22h36m 23h25m 4h52m 0.07
2020-04-26 4h50m 5h33m 21h55m 22h38m 4h50m 0.13
2020-04-27 4h48m 5h31m 21h57m 22h40m 0h28m 4h48m 0.21
2020-04-28 4h46m 5h29m 21h58m 22h42m 1h27m 4h46m 0.3
2020-04-29 4h44m 5h28m 22h00m 22h44m 2h21m 4h44m 0.4
2020-04-30 4h42m 5h26m 22h01m 22h45m 3h08m 4h42m 0.52

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2018/09/27/.

NASA Calendar of Planetary Events

   Date      Time    Event
Apr 1  We  05:12 am  Moon North Dec.: 23.7° N
    1  We  06:21 am  First Quarter
    1  We            Venus: 45.9° E
    3  Fr  02:24 am  Moon-Beehive: 1.3° S
    3  Fr  10:39 am  Venus-Pleiades: 0.3° S
    7  Tu  02:08 pm  Moon Perigee: 356900 km
    7  Tu  10:35 pm  Full Moon (super moon)
   12  Su  10:58 pm  Moon Descending Node
   13  Mo  05:03 pm  Moon South Dec.: 23.8° S
   14  Tu  06:56 pm  Last Quarter
   14  Tu  07:04 pm  Moon-Jupiter: 2.1° N
   15  We  05:26 am  Moon-Saturn: 2.6° N
   16  Th  12:33 am  Moon-Mars: 2.2° N
   20  Mo  03:01 pm  Moon Apogee: 406500 km
   22  We  02:07 am  Lyrid Meteor Shower: ZHR = 20
   22  We  10:26 pm  New Moon
   26  Su  06:19 am  Uranus Conjunction
   26  Su  11:23 am  Moon-Venus: 6.6° N
   27  Mo  01:54 pm  Moon Ascending Node
   27  Mo            Venus greatest brilliancy
   28  Tu  11:23 am  Moon North Dec.: 23.9° N
   30  Th  09:17 am  Moon-Beehive: 1.6° S
   30  Th  04:38 pm  First Quarter
May 1  Fr            Venus: 38° E

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html.

Sun and Moon Rising and Setting Events

LU                  Ephemeris of Sky Events for Interlochen/TC
April, 2020    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Wed  1| 07:22a  08:11p  12:48 | 09:15p  06:18a |F Qtr Set  04:23a   56%|
|Thu  2| 07:20a  08:12p  12:51 | 09:17p  06:16a |      Set  05:09a   67%|
|Fri  3| 07:18a  08:13p  12:54 | 09:18p  06:14a |      Set  05:48a   77%|
|Sat  4| 07:17a  08:14p  12:57 | 09:20p  06:12a |      Set  06:22a   86%|
+------+-----------------------+----------------+-----------------------+
|Sun  5| 07:15a  08:16p  13:00 | 09:21p  06:10a |      Set  06:53a   93%|
|Mon  6| 07:13a  08:17p  13:03 | 09:23p  06:08a |      Set  07:21a   98%|
|Tue  7| 07:11a  08:18p  13:06 | 09:24p  06:06a |Full  Rise 07:55p  100%|
|Wed  8| 07:09a  08:19p  13:09 | 09:25p  06:04a |      Rise 09:16p   99%|
|Thu  9| 07:08a  08:21p  13:12 | 09:27p  06:02a |      Rise 10:36p   95%|
|Fri 10| 07:06a  08:22p  13:15 | 09:28p  06:00a |      Rise 11:54p   88%|
|Sat 11| 07:04a  08:23p  13:19 | 09:30p  05:58a |      Rise 01:07a   80%|
+------+-----------------------+----------------+-----------------------+
|Sun 12| 07:02a  08:24p  13:22 | 09:31p  05:56a |      Rise 02:13a   70%|
|Mon 13| 07:01a  08:26p  13:25 | 09:33p  05:54a |      Rise 03:09a   60%|
|Tue 14| 06:59a  08:27p  13:28 | 09:34p  05:52a |L Qtr Rise 03:56a   50%|
|Wed 15| 06:57a  08:28p  13:30 | 09:36p  05:50a |      Rise 04:34a   40%|
|Thu 16| 06:55a  08:29p  13:33 | 09:37p  05:48a |      Rise 05:05a   30%|
|Fri 17| 06:54a  08:31p  13:36 | 09:39p  05:46a |      Rise 05:32a   22%|
|Sat 18| 06:52a  08:32p  13:39 | 09:40p  05:44a |      Rise 05:55a   15%|
+------+-----------------------+----------------+-----------------------+
|Sun 19| 06:50a  08:33p  13:42 | 09:42p  05:42a |      Rise 06:17a    9%|
|Mon 20| 06:49a  08:34p  13:45 | 09:43p  05:40a |      Rise 06:37a    4%|
|Tue 21| 06:47a  08:36p  13:48 | 09:45p  05:38a |      Rise 06:58a    1%|
|Wed 22| 06:45a  08:37p  13:51 | 09:46p  05:36a |New   Set  08:15p    0%|
|Thu 23| 06:44a  08:38p  13:54 | 09:48p  05:34a |      Set  09:18p    1%|
|Fri 24| 06:42a  08:39p  13:57 | 09:50p  05:32a |      Set  10:21p    3%|
|Sat 25| 06:41a  08:41p  13:59 | 09:51p  05:30a |      Set  11:25p    8%|
+------+-----------------------+----------------+-----------------------+
|Sun 26| 06:39a  08:42p  14:02 | 09:53p  05:29a |      Set  12:27a   14%|
|Mon 27| 06:37a  08:43p  14:05 | 09:54p  05:27a |      Set  01:26a   22%|
|Tue 28| 06:36a  08:44p  14:08 | 09:56p  05:25a |      Set  02:20a   31%|
|Wed 29| 06:34a  08:45p  14:11 | 09:57p  05:23a |      Set  03:07a   41%|
|Thu 30| 06:33a  08:47p  14:13 | 09:59p  05:21a |F Qtr Set  03:47a   52%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset

Generated using my LookingUp for DOS program.

03/30/2020 – Ephemeris – Following the Moon night to night

March 30, 2020 Comments off

Ephemeris for Monday, March 30th. Today the Sun will be up for 12 hours and 42 minutes, setting at 8:08, and it will rise tomorrow at 7:24. The Moon, 2 days before first quarter, will set at 2:32 tomorrow morning.

Now that clear skies are mostly back we can follow, night by night the progress of the Moon, now as its phase waxes and moves eastward at the same time each night. With the naked-eye the large darker lunar seas slowly reveal the face of the Man in the Moon, or the Chinese upside down Jade Rabbit pounding medicine with his mortar and pestle. With binoculars or telescope, more detail is revealed every night as the terminator, the sunrise line before full moon uncovers more lunar territory, with their long morning shadows. It’s the shadows that show the detail on the Moon, which is dark gray on darker gray. For the most part the surface of the Moon has been worn down by eons of meteoroid impacts and their ejecta.

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

Addendum

Jade Rabbit on the Moon

Jade Rabbit and Mortar on the Moon. Credit: Zeimusu, Creative Commons.

Cratewrs near the termonator

Craters near the Moon’s terminator showing how the low Sun brings out the detail. Credit Bob Moler, the author on 06/11/2011.

03/27/2020 – Ephemeris – Enjoying astronomy when sheltering at home

March 27, 2020 Comments off

Ephemeris for Friday, March 27th. Today the Sun will be up for 12 hours and 32 minutes, setting at 8:04, and it will rise tomorrow at 7:30. The Moon, 3 days past new, will set at 11:25 this evening.

With the coronavirus or COVID-19 pandemic hitting our area many of us are stuck in our homes waiting it out. It may be awhile. That’s OK for some of us. That’s because astronomical observation is in many ways a solitary pursuit. My mother taught me the first two constellations. She could never wake me to view the Perseid meteors of August. After that I learned the rest on my own, the first batch on a morning paper route in winter, previewing the spring and summer skies. Staying at home doesn’t mean staying indoors. Going out in the back yard or dark area alone also counts. It’s proximity to other people that’s the problem. I find that being alone out under the stars makes me feel that the Earth and its worries are a trillion miles away.

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

Addendum

Some constellation star fields guaranteed to be trillions of miles away:

Orion

Orion in a 30 second exposure taken at the Sleeping Bear Dunes National Lakeshore Dune Climb February, 18, 2017 by Bob Moler. Click on image to enlarge a bit.

Pleiades and Hyades

Actual photo of the Pleiades to the right of the Hyades, the face of Taurus the bull. Credit Bob Moler

03/26/2020 – Ephemeris – A spring warning about thin ice in the sky

March 26, 2020 Comments off

Ephemeris for Thursday, March 26th. Today the Sun will be up for 12 hours and 29 minutes, setting at 8:03, and it will rise tomorrow at 7:31. The Moon, 2 days past new, will set at 10:22 this evening.

The Anishinaabe peoples of the Great Lakes Region, which includes the Ottawa, Chippewa and Ojibwe Indians have one constellation of winter. It is The Winter Maker which uses many of Orion’s stars and whose arms stretch from Aldebaran in Taurus the bull to Procyon the Little Dog Star, embracing the whole of the winter sky. Now that spring is here he is sinking into the west. The first constellation of spring is Curly Tail, or the Great Underwater Panther. Which uses the stars of Leo the lion’s backward question mark as its tail and the small knot of stars that are the head of Hydra the water snake below Cancer the crab as its head. The warning: Keep off the thinning ice or break through and be snatched by the panther that lives below.

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

Addendum

Great Underwater Panther animation_9 pm late March

Great Underwater Panther finder animation relating western to Anishinaabe constellations for 9 p.m. in late March. Click on image to enlarge. Created using Stellarium.

03/25/2020 – Ephemeris – Let’s look at the naked-eye planets for this week

March 25, 2020 Comments off

Ephemeris for Wednesday, March 25th. Today the Sun will be up for 12 hours and 26 minutes, setting at 8:02, and it will rise tomorrow at 7:33. The Moon, 1 day past new, will set at 9:21 this evening.

Let’s look at the naked-eye planets for this week. Venus is our evening star shining brightly in the west. It will set at 12:14 a.m. The rest of the planet action is in the morning sky where there are three planets close together in the southeast. Bright Jupiter will rise first at 4:35 a.m. Followed by Mars, left and below, rising at 4:50 a.m. It’s now as bright as a first magnitude star because it’s down to 140 million (226 million km) miles away, as the Earth slowly overtakes it at the rate of about 5 million miles (8 million km) a week. It’s brighter than the star Antares in the south-southwest. And lastly, Saturn will rise at 5:01 a.m. Mars is about half way between Jupiter and Saturn. It will pass Saturn next Tuesday.

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

Addendum

Day and a half old Moon

Day and a half old Moon low over a Lake Michigan horizon tonight at 8:30 p.m. March 25, 2020. The bright edge of the Moon will be a sit brighter, and the earthshine on the night side of the Moon a bit dimmer. Created using Stellarium.

Venus and the setting winter stars

Venus and the setting winter stars tonight at 10 p.m. March 25, 2020. Click on the image to enlarge. Created using Stellarium.

Morning planets

Saturn, Mars and Jupiter with the southern summer stars at 6:30 a.m. tomorrow March 26, 2020. Mars will pass Saturn on the 31st. Click on the image to enlarge. Created using Stellarium.

Telescopic planets

The planets as seen in a telescope with the same magnification. Venus in the evening and Jupiter and Saturn in the morning on the night of March 25/26, 2020. Apparent diameters: Venus, 23.85″; Jupiter, 36.46″; Saturn, 15.99″, rings, 37.26″. Mars at 6.22″ won’t be added until it reaches 10″. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge. Created using Cartes du Ciel (Sky Charts).

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 25, 2020. The night ends on the left with sunrise on the 26th. Click on the image to enlarge. Created using my LookingUp program.

03/24/2020 – Ephemeris – Venus reaches greatest eastern elongation from the Sun today

March 24, 2020 Comments off

Ephemeris for Tuesday, March 24th. Today the Sun will be up for 12 hours and 23 minutes, setting at 8:01, and it will rise tomorrow at 7:35. The Moon is new today, and won’t be visible.

Today, around 6 p.m. the planet Venus will reach its greatest eastern elongation from the Sun. That means Venus will appear as far east of the Sun that it can get at an angle of 46.1 degrees. Venus, like Mercury orbits the Sun inside the Earth’s orbit, so is always seen close to the Sun. In telescopes Venus will look like a tiny first quarter Moon. That’s for the same reason. The Sun is illuminating half of the side we can see. Venus is moving directly toward us now, at a distance of 66.5 million miles (117 million km). As Venus approaches us, it will grow in size in telescopes, becoming larger in appearance than Jupiter the largest planet and a thinner and thinner crescent. It will leave the evening sky, passing between the Earth and the Sun, only 27 million miles (43 million km) away on June 3rd.

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

Addendum

Venus at greatest eastern elongation

Venus at greatest eastern elongation seen tonight at 8:20 p.m. The red line its orbit if we could see it tonight. Venus will be moving to the right and down in the coming days. Created using Stellarium.

03/23/2020 – Ephemeris – See zodiacal light in the evening

March 23, 2020 Comments off

Ephemeris for Monday, March 23rd. Today the Sun will be up for 12 hours and 20 minutes, setting at 7:59, and it will rise tomorrow at 7:37. The Moon, 1 day before new, will rise at 8:11 tomorrow morning.

With the bright moon out of the sky for a few more nights it’s time to look for the zodiacal light in the evening. It’s is a faint but towering glow that can be seen after the end of astronomical twilight on moonless nights. It is seen in the west in the evening in late winter and early spring and in the east in the morning in late summer and early autumn. The axis of the glow is the ecliptic, the apparent annual path of the Sun in the sky, along which lie the constellations of the zodiac. Right now the end of astronomical twilight is about 9:41 p.m. and advancing at a rate of a minute or two each night. Go to a spot with a dark western sky, no big cities or towns out that way. Zodiacal light is caused by dust spread out around the Sun.

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

Addendum

Zodiacal Light

Much enhanced Zodiacal Light from the my back yard at 9:31 p.m. March 16, 2018, 5 minutes after the official end of astronomical twilight. Canon EOS Rebel T5 18mm f.l., f/3.5, 6 sec. ISO 12,800 . The clouds on the left appear to be illuminated by the lights of the towns of Beulah and Frankfort 20+ miles away.