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Posts Tagged ‘May’

04/30/2021 – Ephemeris – Previewing March skies

April 30, 2021 Comments off

This is Bob Moler with Ephemeris for Arbor Day, Friday, April 30th. Today the Sun will be up for 14 hours and 13 minutes, setting at 8:46, and it will rise tomorrow at 6:32. The Moon, 3 days before last quarter, will rise at 1:34 tomorrow morning.

The month of May starts tomorrow, when spring really gets going. Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 15 minutes tomorrow to 15 hours 19 minutes on the 31st. The altitude, or angle, of the Sun above the southern horizon at local noon will ascend from 61 degrees now to 67 degrees at month’s end. The altitude of the Sun in the Straits area will be a degree lower than that, but your daylight hours will be a few minutes longer. Local apparent noon this month, when the Sun passes due south, will be about 1:38 p.m. This is the month of the Eta Aquariid meteor shower which will reach its peak next week Thursday morning. There will be about a 2-hour viewing period starting at 3:15 am. We will get a chance to see the beginning of a lunar eclipse near sunrise on Wednesday the 26th.

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

Addendum

May Evening Star Chart

Star Chart for May 2021 (11 p.m. EDT May 15, 2021). 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 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, West 75° longitude. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.
Note the chart times of 11 p.m. and 5 a.m. are for the 15th. For each week before the 15th add ½ hour (28 minutes if you’re picky). For each week after the 15th subtract ½ hour, or 28 minutes. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog for weekly positions.

May Morning Star Chart

Star Chart for May mornings 2021 (5 a.m. EDT May 15, 2020). 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 dipper drips on Leo
  • Follow the arc of the handle of the Big Dipper to the star Arcturus, and
  • Extend like a spike to Spica,
  • EaqR is the radiant of the Aquariid meteor shower that peaks on the 5th.  Best viewing is before the peak this year due to the bright Moon.

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning Twilight Evening Twilight Dark Night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2021-05-01 4h40m 5h24m 22h02m 22h47m 22h47m 1h35m 0.67
2021-05-02 4h38m 5h23m 22h04m 22h49m 22h49m 2h32m 0.57
2021-05-03 4h36m 5h21m 22h05m 22h51m 22h51m 3h17m 0.46
2021-05-04 4h33m 5h19m 22h07m 22h53m 22h53m 3h52m 0.36
2021-05-05 4h31m 5h17m 22h09m 22h55m 22h55m 4h20m 0.27
2021-05-06 4h29m 5h16m 22h10m 22h57m 22h57m 4h29m 0.18
2021-05-07 4h27m 5h14m 22h12m 22h59m 22h59m 4h27m 0.11
2021-05-08 4h25m 5h12m 22h13m 23h01m 23h01m 4h25m 0.06
2021-05-09 4h23m 5h11m 22h15m 23h03m 23h03m 4h23m 0.02
2021-05-10 4h21m 5h09m 22h16m 23h05m 23h05m 4h21m 0
2021-05-11 4h19m 5h07m 22h18m 23h07m 23h07m 4h19m 0
2021-05-12 4h17m 5h06m 22h19m 23h09m 23h09m 4h17m 0.02
2021-05-13 4h15m 5h04m 22h21m 23h11m 23h11m 4h15m 0.05
2021-05-14 4h13m 5h03m 22h23m 23h13m 4h13m 0.1
2021-05-15 4h11m 5h01m 22h24m 23h15m 0h07m 4h11m 0.17
2021-05-16 4h09m 5h00m 22h26m 23h17m 1h00m 4h09m 0.25
2021-05-17 4h07m 4h58m 22h27m 23h19m 1h46m 4h07m 0.34
2021-05-18 4h05m 4h57m 22h28m 23h21m 2h25m 4h05m 0.44
2021-05-19 4h03m 4h56m 22h30m 23h23m 2h58m 4h03m 0.54
2021-05-20 4h01m 4h54m 22h31m 23h24m 3h26m 4h01m 0.65
2021-05-21 4h00m 4h53m 22h33m 23h26m 3h51m 4h00m 0.76
2021-05-22 3h58m 4h52m 22h34m 23h28m 0.85
2021-05-23 3h56m 4h51m 22h36m 23h30m 0.92
2021-05-24 3h54m 4h49m 22h37m 23h32m 0.98
2021-05-25 3h53m 4h48m 22h38m 23h34m 1
2021-05-26 3h51m 4h47m 22h40m 23h36m 0.99
2021-05-27 3h49m 4h46m 22h41m 23h38m 0.95
2021-05-28 3h48m 4h45m 22h42m 23h39m 23h39m 0.89
2021-05-29 3h46m 4h44m 22h43m 23h41m 23h41m 0h19m 0.81
2021-05-30 3h45m 4h43m 22h45m 23h43m 23h43m 1h11m 0.72
2021-05-31 3h44m 4h42m 22h46m 23h44m 23h44m 1h52m 0.61

The twilight calendar was generated using Cartes du Ciel (Sky Charts), with some corrections.

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

May  1  Sa            Venus: 9.4° E
     1  Sa   5:37 am  Moon South Dec.: 25.6° S
     3  Mo   1:02 pm  Moon-Saturn: 4.4° N
     3  Mo   3:50 pm  Last Quarter
     3  Mo  11:01 pm  Mercury-Pleiades: 2.2° S
     4  Tu   5:00 pm  Moon-Jupiter: 4.9° N
     4  Tu   9:30 pm  Eta Aquariid Shower: ZHR = 60
    11  Tu   3:00 pm  New Moon
    11  Tu   5:54 pm  Moon Apogee: 406500 km
    13  Th   6:29 am  Moon Ascending Node
    13  Th   1:59 pm  Moon-Mercury: 2.4° N
    15  Sa   6:25 pm  Moon North Dec.: 25.6° N
    16  Su  12:47 am  Moon-Mars: 1.6° S
    17  Mo   1:59 am  Mercury Elongation: 22° E
    17  Mo   9:08 pm  Moon-Beehive: 3.1° S
    19  We   3:13 pm  First Quarter
    25  Tu   9:52 pm  Moon Perigee: 357300 km
    26  We   7:14 am  Full Moon
    26  We   7:19 am  Total Lunar Eclipse (Start is visible here)
    26  We   3:38 pm  Moon Descending Node
    28  Fr   3:21 pm  Moon South Dec.: 25.6° S
    28  Fr  11:01 pm  Mercury-Venus: 0.4° N
    30  Su   9:22 pm  Moon-Saturn: 4.3° N
    31  Mo   7:39 am  Mars-Pollux: 5.3° S
Jun  1  Tu            Venus: 17.5° 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
May, 2021    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sat  1| 06:32a  08:48p  14:15 | 10:00p  05:20a |      Rise 02:32a   70%|
+------+-----------------------+----------------+-----------------------+
|Sun  2| 06:30a  08:49p  14:18 | 10:02p  05:18a |      Rise 03:17a   59%|
|Mon  3| 06:29a  08:50p  14:21 | 10:03p  05:16a |L Qtr Rise 03:52a   48%|
|Tue  4| 06:28a  08:51p  14:23 | 10:05p  05:14a |      Rise 04:20a   38%|
|Wed  5| 06:26a  08:53p  14:26 | 10:06p  05:13a |      Rise 04:44a   28%|
|Thu  6| 06:25a  08:54p  14:28 | 10:08p  05:11a |      Rise 05:04a   20%|
|Fri  7| 06:24a  08:55p  14:31 | 10:09p  05:09a |      Rise 05:24a   13%|
|Sat  8| 06:22a  08:56p  14:33 | 10:11p  05:08a |      Rise 05:43a    7%|
+------+-----------------------+----------------+-----------------------+
|Sun  9| 06:21a  08:57p  14:36 | 10:13p  05:06a |      Rise 06:03a    3%|
|Mon 10| 06:20a  08:58p  14:38 | 10:14p  05:04a |      Rise 06:25a    1%|
|Tue 11| 06:18a  09:00p  14:41 | 10:16p  05:03a |New   Set  09:03p    0%|
|Wed 12| 06:17a  09:01p  14:43 | 10:17p  05:01a |      Set  10:06p    1%|
|Thu 13| 06:16a  09:02p  14:45 | 10:19p  05:00a |      Set  11:08p    4%|
|Fri 14| 06:15a  09:03p  14:48 | 10:20p  04:58a |      Set  12:07a    9%|
|Sat 15| 06:14a  09:04p  14:50 | 10:22p  04:57a |      Set  01:00a   15%|
+------+-----------------------+----------------+-----------------------+
|Sun 16| 06:13a  09:05p  14:52 | 10:23p  04:55a |      Set  01:46a   23%|
|Mon 17| 06:12a  09:06p  14:54 | 10:25p  04:54a |      Set  02:25a   32%|
|Tue 18| 06:11a  09:08p  14:56 | 10:26p  04:52a |      Set  02:57a   42%|
|Wed 19| 06:10a  09:09p  14:59 | 10:28p  04:51a |F Qtr Set  03:26a   52%|
|Thu 20| 06:09a  09:10p  15:01 | 10:29p  04:50a |      Set  03:51a   63%|
|Fri 21| 06:08a  09:11p  15:03 | 10:30p  04:48a |      Set  04:14a   73%|
|Sat 22| 06:07a  09:12p  15:04 | 10:32p  04:47a |      Set  04:38a   83%|
+------+-----------------------+----------------+-----------------------+
|Sun 23| 06:06a  09:13p  15:06 | 10:33p  04:46a |      Set  05:04a   91%|
|Mon 24| 06:05a  09:14p  15:08 | 10:35p  04:45a |      Set  05:33a   97%|
|Tue 25| 06:04a  09:15p  15:10 | 10:36p  04:44a |      Set  06:09a  100%|
|Wed 26| 06:04a  09:16p  15:12 | 10:37p  04:42a |Full  Rise 09:57p  100%|
|Thu 27| 06:03a  09:17p  15:13 | 10:39p  04:41a |      Rise 11:14p   96%|
|Fri 28| 06:02a  09:18p  15:15 | 10:40p  04:40a |      Rise 12:19a   91%|
|Sat 29| 06:01a  09:19p  15:17 | 10:41p  04:39a |      Rise 01:11a   83%|
+------+-----------------------+----------------+-----------------------+
|Sun 30| 06:01a  09:19p  15:18 | 10:42p  04:38a |      Rise 01:52a   74%|
|Mon 31| 06:00a  09:20p  15:19 | 10:43p  04:38a |      Rise 02:23a   64%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset

Generated using my LookingUp for DOS program.

Categories: Ephemeris Program, Month preview Tags:

05/11/2020 – Ephemeris – Looking out of the Milky Way in May

May 11, 2020 Comments off

This is Ephemeris for Monday, May 11th. Today the Sun will be up for 14 hours and 41 minutes, setting at 9:00, and it will rise tomorrow at 6:17. The Moon, 3 days before last quarter, will rise at 1:51 tomorrow morning.

When it’s finally dark enough to see the stars in a dark sky at the end of astronomical twilight at 11 p.m. the question might be: “Where did the Milky Way go?” The band of the Milky Way is actually nearly ringing the horizon. Part of it runs through the W shaped constellation of Cassiopeia, just above the northern horizon. But the great amount of the Earth’s atmosphere we have to look through that low in the sky dims it to invisibility. The Milky Way is what we see of our galaxy, or more accurately our part of our galaxy whose shape has the rough proportions of a pancake. Remember, we’re in it. In spring we’re mostly looking through the thin side past relatively nearby stars to the intergalactic space beyond.

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

Addendum

Milky Way on May 15 11 pm 2020

The Dome of the sky on May 15, 2020 at 11 pm with the Milky Way at its lowest in the sky. Credit my LookingUp program.

Our place in the Milky Way.

Our place in the Milky Way. Note that we appear to be in a barred spiral galaxy. The arms are numbered and named. 3kpc is the 3 kiloparsec arm. 3kpc = 9,780 light years. The Sun is about 27,000 light years from the center. Credit NASA and Wikimedia Commons, via EarthSky.org.

The summer and winter Milky Way viewing directions.

The summer and winter Milky Way viewing directions. During Spring and Autumn, we look out the sides to the universe beyond. Credit Credit: NASA with annotations by Bob King at Universe Today.

Categories: Ephemeris Program, Milky Way Tags:

04/30/2012 – Ephemeris – Preview May Skies

April 30, 2012 Comments off

Ephemeris for Monday, April 30th.  The sun rises at 6:33.  It’ll be up for 14 hours and 13 minutes, setting at 8:46.   The moon, 1 day past first quarter, will set at 3:41 tomorrow morning.

Tomorrow we’ll start the month when the promise of spring is finally fulfilled.  Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 15 minutes tomorrow to 15 hours 19 minutes on the 31st.  The altitude, or angle, of the sun above the southern horizon at local noon will ascend from 60 degrees today to 67 degrees at month’s end.  The altitude of the sun in the Straits area will be a degree lower than that but your daylight will be a few minutes longer.  Local apparent noon this month, when the sun passes due south, will be about 1:38 p.m.  The big event of this month will be a partial eclipse of the sun on Sunday May 20th, where we’ll see about 45 minutes of the eclipse as the sun sets.

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

04/29/11 – Ephemeris – May preview

April 29, 2011 Comments off

Arbor Day, Friday, April 29th.  The sun rises at 6:36.  It’ll be up for 14 hours and 8 minutes, setting at 8:44.   The moon, 4 days before new, will rise at 5:00 tomorrow morning.

Let’s look ahead at the month of May, the month when the promise of spring is finally fulfilled.  Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 13 minutes Sunday to 15 hours 18 minutes on the 31st.  The altitude, or angle, of the sun above the southern horizon at local noon will ascend from 60 degrees tomorrow to 67 degrees at month’s end.  The altitude of the sun in the Straits area will be a degree lower than that.  Local apparent noon this month, when the sun passes due south, will be about 1:38 p.m.  This is the month of the Eta Aquarid meteor shower which will reach its peak next week.  We’ll have dark skies for this very early morning meteor shower that’s related to Halley’s Comet.

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

Categories: Ephemeris Program, Events Tags: