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02/28/2020 – Ephemeris – Previewing March Skies

February 28, 2020 Comments off

Ephemeris for Friday, February 28th. Today the Sun will be up for 11 hours and 5 minutes, setting at 6:28, and it will rise tomorrow at 7:21. The Moon, 3 days before first quarter, will set at 11:30 this evening.

Let’s look at the skies for the month of March. The Sun will pass the celestial equator as the promising season of spring will begin. Daylight hours in the Interlochen/Traverse City area and will increase from 11 hours and 11 minutes Sunday to 12 hours 45 minutes on the 31st. The altitude, or angle, of the Sun above the southern horizon at local noon will be 38 degrees Sunday and will ascend to nearly 50 degrees on the 31st. Spring will start on the 19th at 11:50 p.m. Part of the fault for that early date is the switch to daylight saving time this early in the year a while back. The Gregorian calendar reform of 1582 will keep the vernal equinox from falling much further back. So spring will come a bit early this year, calendar-wise.

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

Addendum

March Evening Star Chart

March Evening Star Chart

Star Chart for March 2020 (10 p.m. EDT March 15, 2020). Click on image to enlarge. Created using my LookingUp program. 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 6 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 45 minutes behind our daylight saving time meridian during EDT).

March Morning Star Chart

March Morning Star Chart

Star Chart for March mornings 2020 (6 a.m. EST March 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.
  • The Summer Triangle appears in red.

Twilight Limits, Nautical and Astronomical

      EST/EDT        
  Morning twilight Evening twilight Dark night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2020-03-01 5h43m 6h17m 19h33m 20h06m 0h33m 5h43m 0.41
2020-03-02 5h41m 6h15m 19h34m 20h08m 1h36m 5h41m 0.52
2020-03-03 5h39m 6h13m 19h35m 20h09m 2h40m 5h39m 0.62
2020-03-04 5h37m 6h11m 19h36m 20h10m 3h42m 5h37m 0.73
2020-03-05 5h36m 6h10m 19h38m 20h12m 4h40m 5h36m 0.82
2020-03-06 5h34m 6h08m 19h39m 20h13m 5h31m 5h34m 0.91
2020-03-07 5h32m 6h06m 19h40m 20h14m 0.97
2020-03-08 6h30m 7h04m 20h42m 21h16m 0.97
2020-03-09 6h28m 7h02m 20h43m 21h17m 1
2020-03-10 6h26m 7h01m 20h44m 21h18m 1
2020-03-11 6h25m 6h59m 20h46m 21h20m 21h20m 22h26m 0.96
2020-03-12 6h23m 6h57m 20h47m 21h21m 21h21m 23h45m 0.9
2020-03-13 6h21m 6h55m 20h48m 21h23m 21h23m 0.81
2020-03-14 6h19m 6h53m 20h50m 21h24m 21h24m 1h01m 0.71
2020-03-15 6h17m 6h51m 20h51m 21h25m 21h25m 2h14m 0.6
2020-03-16 6h15m 6h49m 20h52m 21h27m 21h27m 3h21m 0.49
2020-03-17 6h13m 6h48m 20h53m 21h28m 21h28m 4h21m 0.38
2020-03-18 6h11m 6h46m 20h55m 21h30m 21h30m 5h13m 0.29
2020-03-19 6h09m 6h44m 20h56m 21h31m 21h31m 5h55m 0.2
2020-03-20 6h11m 6h46m 21h01m 21h36m 21h36m 6h11m 0.12
2020-03-21 6h09m 6h44m 21h03m 21h38m 21h38m 6h09m 0.07
2020-03-22 6h07m 6h42m 21h04m 21h39m 21h39m 6h07m 0.03
2020-03-23 6h04m 6h40m 21h05m 21h41m 21h41m 6h04m 0
2020-03-24 6h02m 6h38m 21h07m 21h42m 21h42m 6h02m 0
2020-03-25 6h00m 6h36m 21h08m 21h44m 21h44m 6h00m 0.02
2020-03-26 5h58m 6h34m 21h10m 21h45m 22h23m 5h58m 0.05
2020-03-27 5h56m 6h32m 21h11m 21h47m 23h25m 5h56m 0.1
2020-03-28 5h54m 6h30m 21h12m 21h48m 5h54m 0.17
2020-03-29 5h52m 6h28m 21h14m 21h50m 0h28m 5h52m 0.25
2020-03-30 5h50m 6h26m 21h15m 21h51m 1h31m 5h50m 0.35
2020-03-31 5h48m 6h24m 21h16m 21h53m 2h33m 5h48m 0.45

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
Mar 1  Su            Venus: 44.6° E
    2  Mo  02:57 pm  First Quarter
    4  We  09:58 am  Moon Ascending Node
    4  We  08:34 pm  Moon North Dec.: 23.4° N
    6  Fr  04:08 pm  Moon-Beehive: 1.1° S
    8  Su  08:09 am  Neptune Conjunction
    9  Mo  01:48 pm  Full Moon
   10  Tu  02:33 am  Moon Perigee: 357100 km
   16  Mo  05:34 am  Last Quarter
   16  Mo  09:00 pm  Moon Descending Node
   17  Tu  10:07 am  Moon South Dec.: 23.5° S
   18  We  04:19 am  Moon-Mars: 0.8° N
   18  We  06:18 am  Moon-Jupiter: 1.6° N
   18  We  08:04 pm  Moon-Saturn: 2.3° N
   19  Th  11:50 pm  Vernal Equinox
   20  Fr  06:24 am  Mars-Jupiter: 0.7° N
   21  Sa  01:48 pm  Moon-Mercury: 4° N
   23  Mo  09:59 pm  Mercury Greatest Elongation: 27.8° W
   24  Tu  05:28 am  New Moon
   24  Tu  11:23 am  Moon Apogee: 406700 km
   24  Tu  05:59 pm  Venus Greatest Elongation: 46.1° E
   31  Tu  12:51 pm  Moon Ascending Node
   31  Tu  04:00 pm  Mars-Saturn: 0.9° N
Apr 1  We            Venus: 45.9° E

All event times prior to 2 a.m. March 8 are given for UTC-5 Eastern Standard Time, after that time are given for UTC-4 Eastern Daylight Time

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.

Sun and Moon Rising and Setting Events

LU                  Ephemeris of Sky Events for Interlochen/TC
March, 2020    Local time zone: EST
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Sun  1| 07:19a  06:31p  11:11 | 07:34p  06:16a |      Set  01:36a   42%|
|Mon  2| 07:17a  06:32p  11:14 | 07:35p  06:14a |F Qtr Set  02:39a   52%|
|Tue  3| 07:15a  06:33p  11:18 | 07:37p  06:12a |      Set  03:41a   62%|
|Wed  4| 07:14a  06:35p  11:21 | 07:38p  06:11a |      Set  04:39a   72%|
|Thu  5| 07:12a  06:36p  11:24 | 07:39p  06:09a |      Set  05:31a   81%|
|Fri  6| 07:10a  06:37p  11:27 | 07:40p  06:07a |      Set  06:15a   89%|
|Sat  7| 07:08a  06:39p  11:30 | 07:42p  06:05a |      Set  06:54a   95%|
+------+-----------------------+----------------+-----------------------+
| EDT  |      Time Change      |                |                       |
|Sun  8| 08:07a  07:40p  11:33 | 08:43p  07:04a |      Set  08:27a   99%|
|Mon  9| 08:05a  07:41p  11:36 | 08:44p  07:02a |Full  Rise 07:46p  100%|
|Tue 10| 08:03a  07:43p  11:39 | 08:46p  07:00a |      Rise 09:07p   97%|
|Wed 11| 08:01a  07:44p  11:42 | 08:47p  06:58a |      Rise 10:26p   92%|
|Thu 12| 07:59a  07:45p  11:46 | 08:48p  06:56a |      Rise 11:45p   85%|
|Fri 13| 07:57a  07:47p  11:49 | 08:50p  06:54a |      Rise 01:01a   75%|
|Sat 14| 07:56a  07:48p  11:52 | 08:51p  06:53a |      Rise 02:14a   65%|
+------+-----------------------+----------------+-----------------------+
|Sun 15| 07:54a  07:49p  11:55 | 08:52p  06:51a |      Rise 03:21a   54%|
|Mon 16| 07:52a  07:50p  11:58 | 08:54p  06:49a |L Qtr Rise 04:21a   44%|
|Tue 17| 07:50a  07:52p  12:01 | 08:55p  06:47a |      Rise 05:12a   34%|
|Wed 18| 07:48a  07:53p  12:04 | 08:56p  06:45a |      Rise 05:55a   25%|
|Thu 19| 07:46a  07:54p  12:07 | 08:58p  06:43a |      Rise 06:31a   17%|
|Fri 20| 07:44a  07:55p  12:11 | 08:59p  06:41a |      Rise 07:00a   10%|
|Sat 21| 07:43a  07:57p  12:14 | 09:00p  06:39a |      Rise 07:26a    5%|
+------+-----------------------+----------------+-----------------------+
|Sun 22| 07:41a  07:58p  12:17 | 09:02p  06:37a |      Rise 07:49a    2%|
|Mon 23| 07:39a  07:59p  12:20 | 09:03p  06:35a |      Rise 08:11a    0%|
|Tue 24| 07:37a  08:01p  12:23 | 09:04p  06:33a |New   Set  08:21p    1%|
|Wed 25| 07:35a  08:02p  12:26 | 09:06p  06:31a |      Set  09:21p    2%|
|Thu 26| 07:33a  08:03p  12:29 | 09:07p  06:29a |      Set  10:22p    6%|
|Fri 27| 07:31a  08:04p  12:32 | 09:09p  06:27a |      Set  11:25p   11%|
|Sat 28| 07:30a  08:06p  12:36 | 09:10p  06:25a |      Set  12:28a   18%|
+------+-----------------------+----------------+-----------------------+
|Sun 29| 07:28a  08:07p  12:39 | 09:11p  06:23a |      Set  01:31a   26%|
|Mon 30| 07:26a  08:08p  12:42 | 09:13p  06:21a |      Set  02:32a   35%|
|Tue 31| 07:24a  08:09p  12:45 | 09:14p  06:20a |      Set  03:30a   45%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset

Generated using my LookingUp for DOS program.

 

02/27/2020 – Ephemeris – Saturday is the intercalary day

February 27, 2020 Comments off

Ephemeris for Thursday, February 27th. Today the Sun will be up for 11 hours and 2 minutes, setting at 6:27, and it will rise tomorrow at 7:22. The Moon, half way from new to first quarter, will set at 10:28 this evening.

Saturday we’re going to have one of those special days that only occur once every 4 years making this a leap year. It’s the intercalary day that compensates for the fact that the earth takes 365 and nearly a quarter day to orbit the Sun. That orbit is a year, and those quarter days are accumulated and added as the last day of February on years divisible by 4. The Gregorian reform makes a slight adjustment on most century years, making century years not divisible by 400 ordinary years to keep the calendar in sync with the seasons. The Romans, from who we’ve gotten our calendar considered the month of February as unlucky, and so they shortened it. Enjoy your extra day on Saturday.

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

 

02-26-2020 – Ephemeris – Let’s look at the naked-eye planets for this week

February 26, 2020 Comments off

Ephemeris for Ash Wednesday, February 26th. Today the Sun will be up for 10 hours and 59 minutes, setting at 6:25, and it will rise tomorrow at 7:24. The Moon, 3 days past new, will set at 9:28 this evening.

Let’s look at the naked-eye planets for this week. Venus is our evening star shining brightly in the southwest in the early evening. It will set at 10:19 p.m. Mars is visible in the morning sky and will rise in the southeast at 4:27 a.m. It’s not very bright because it’s 161 million (260 million km) miles away, but it’s getting slowly closer to the Earth at the rate of about 6 million miles (9 million km) a week. However it’s brighter than Betelgeuse. Jupiter will rise at 5:06 a.m. Lastly, Saturn will rise at 5:39 tomorrow morning. Jupiter is currently about 9 degrees away from Saturn, a bit less than the width of your fist held at arms length. It will continue to approach Saturn until their paths cross on December 21st.

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

Addendum

Venus and the Moon

Venus and the Moon in the western sky at 7:30 p.m. or about an hour after sunset. February 26, 2020. Created using Stellarium.

Morning planets and stars

The morning planets and stars visible in the southern sky at 6:30 a.m. tomorrow morning February 37, 2020. The star Antares is in the constellation of Scorpius. Mars sits on top of the lid of the Teapot asterism of the constellation of Sagittarius the archer. Jupiter and Saturn are seen to the lower left. Click on the image to enlarge. Created using Stellarium.

Telescopic views of the 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 February 26/27, 2020. Apparent diameters: Venus, 18.3″; Jupiter, 34.0″; Saturn, 15.4″, rings, 36.0″. Mars at 5.4″ won’t be added until it reaches 10″. The ” symbol means seconds of arc (1/3600th of a degree.) 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 February 26, 2020. The night ends on the left with sunrise on the 27th. Click on the image to enlarge. Created using my LookingUp program.

02/25/2020 – Ephemeris – Mercury at inferior conjunction with the Sun today

February 25, 2020 Comments off

Ephemeris for Fat Tuesday, February 25th. Today the Sun will be up for 10 hours and 56 minutes, setting at 6:24, and it will rise tomorrow at 7:26. The Moon, 2 days past new, will set at 8:27 this evening.

A bit more than two weeks ago Mercury was visible in the evening twilight at its greatest elongation from the Sun, then at 8:37 this evening it will pass between the Earth and the Sun and enter the morning sky. The event is called an inferior conjunction. That’s not a dig on the quality of the event. Indeed an inferior conjunctions are more important and can produce a transit of the planet across the Sun. A rare and formerly important event when we were trying to determine the distance to the Sun. In astronomy an inferior planet is one that orbits the Sun inside the Earth’s orbit. A superior planet orbits the Sun farther than the Earth. It’s not a sign of quality. The best time to spot Mercury in the morning is in August to October, so we’ll miss Mercury this time.

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

Addendum

Mercury at inferior conjunction

Mercury about 7 hours before inferior conjunction February 25, 2020 near local solar noon. The last inferior conjunction of Mercury on November 11, 2019 Mercury passed across the Sun’s disk in a transit. The red ellipse is Mercury’s orbit as seen From the Earth. It’s orbit is tilted about 7 degrees from the Earth’s orbit, so transits are fairly rare events. Created using Stellarium.

02/24/2020 – Ephemeris – Conflict in the skies: Orion vs. Taurus

February 24, 2020 Comments off

Ephemeris for Monday, February 24th.  Today the Sun will be up for 10 hours and 53 minutes, setting at 6:23, and it will rise tomorrow at 7:27.  The Moon, 1 day past new, will set at 7:26 this evening.

The classical constellation figures of Orion the hunter and Taurus the bull appear to be interacting in the sky. Orion is in the south at 9 p.m. An angry Taurus, a bit above him in the southwest, appears to be charging at Orion who appears to be facing him with lion skin shield and an upraised club. Orion’s two hunting dogs, canes major and minor, appear to be unconcerned. The face of Taurus the bull is a letter V shape of faint stars with a bright reddish star at the upper left tip of the V called Aldebaran the bull’s angry bloodshot eye. There’s no mythological story that goes with this.  Both Orion and Taurus have their own myths associated with them separate from their apparent clash in the heavens.

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

Addendum

Orion vs Taurus

Conflict in the skis: Taurus is charging Orion. Seen at 9 p.m. in late February. Created using Stellarium and the dimming of Betelgeuse in GIMP.

022/21/2020 – Ephemeris – The almost invisible unicorn

February 21, 2020 Comments off

Ephemeris for Friday, February 21st. Today the Sun will be up for 10 hours and 44 minutes, setting at 6:19, and it will rise tomorrow at 7:32. The Moon, 2 days before new, will rise at 7:27 tomorrow morning.

Among all the constellations in the sky of animals real and mythical, there is also a unicorn. It’s called Monoceros, and inhabits the southern sky at 9 p.m. bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left. Unfortunately for observers without optical aid Monoceros, though large, is devoid of any but the faintest stars. Maybe that’s why no one sees unicorns anymore. It has many faint stars because the Milky Way runs through it. To the telescope it is a feast of faint nebulae or clouds of gas and dust, the birth place of stars, including the red rose of the Rosette Nebula, and the strange and tiny Hubble’s Variable Nebula. It contains no bright stars, but a wealth of wonders below naked eye visibility.

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

Addendum

Monoceros the unicorn

Monoceros the unicorn seen mostly inside the Winter Triangle of Betelgeuse, Sirius and Procyon. Note the star in the unicorn’s right hoof denoted with a funny B. That’s Beta Monocerotis,a triple star visible in small telescopes. Created using Stellarium with additions.

Rosette Nebula

Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech

Hubble's Variable Nebula

Hubble’s Variable Nebula photographed appropriately enough by the Hubble Space Telescope. Credit: NASA/ESA and The Hubble Heritage Team (AURA/STScI).

Beta Monocerotis

Telescopic Beta Monocerotis. William Hershel, discoverer of Uranus, said that it was “One of the most beautiful sights in the heavens.” Credit: F. Ringwald, Fresno State.

02/20/2020 – Ephemeris – The Winter Triangle

February 20, 2020 Comments off

Ephemeris for Thursday, February 20th. Today the Sun will be up for 10 hours and 41 minutes, setting at 6:17, and it will rise tomorrow at 7:34. The Moon, 3 days before new, will rise at 6:53 tomorrow morning.

I usually talk about the Winter Circle of bright stars, but some other astronomers talk about the Winter Triangle. The stars involved are Betelgeuse in the hunter Orion, Sirius in Canis Major, Orion’s large hunting dog, and Procyon in Canis Minor, his other small hunting dog. These three stars enclose a rather blank piece of sky with the faint Milky Way running through it and the equally invisible constellation of Monoceros the unicorn. The Summer Triangle has three bright stars with no other close competition. The Winter Triangle has 4 other bright stars near it. Any three of these would make a nice triangle. One of these stars, Betelgeuse has been the news recently because it is dimming to an unprecedented degree.

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

Addendum

Winter Triangle

The Winter Triangle. It enclose a pretty blank space where Monoceros the unicorn lies. Created using Stellarium with my annotations for the Winter Triangle. By the way, Betelgeuse is currently only as bright as Bellatrix, the star next to the “n” in Orion.