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Archive for March, 2017

03/31/2017 – Ephemeris – Previewing April Skies

March 31, 2017 Comments off

Ephemeris for Friday, March 31st.  The Sun will rise at 7:24.  It’ll be up for 12 hours and 44 minutes, setting at 8:09.  The Moon, 3 days before first quarter, will set at 12:35 tomorrow morning.

The second quarter of the year begins with April Fools Day tomorrow.  Daylight hours in the Interlochen/Traverse City area and will increase from 12 hours and 47 minutes tomorrow to 14 hours 12 minutes on April 30th as spring really takes hold.  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 April 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.  Jupiter will reach opposition from the Sun this month, and be a great planet to view in a telescope all night long.

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

Addenda

April Evening Star Chart

April Star Chart

Star Chart for April 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, 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 1:45 or 0:45  earlier than the current time if you were near your time meridian.

April Morning Chart

April Morning Star Chart

Star Chart for April 2017 mornings. 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
  • Follow the arc of the handle of the Big Dipper to the star Arcturus, and
  • Straighten to a spike to Spica
  • The Summer Triangle is in red
  • The Lyrid meteor shower radiant is in yellow and marked LyrR

Evening nautical twilight ends at 9:17 p.m. EDT on the 1st, increasing to 10:01 p.m. EDT on the 30th.
Evening astronomical twilight ends at 9:54 p.m. EDT on the 1st, increasing to 10:45 p.m. EDT on the 30th.
Morning astronomical twilight starts at 5:46 a.m. EDT on the 1st, and increasing to 4:42 a.m. EDT on the 30th.
Morning nautical twilight starts at 6:23 a.m. EDT on the 1st, and Increasing to 5:26 a.m. EDT on the 30th.

NASA Calendar of Planetary Events

Credit:  Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)

To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

Times are Eastern Time and follow the time change dates.

Date        Time    Event
Apr 01  Sa  Venus: 13.4° W
    01  Sa 04:49 Moon-Aldebaran: 0.3° S
    01  Sa 05:59 Mercury Greatest Eastern Elongation: 19°
    03  Mo 02:12 Moon North Dec.: 19° N
    03  Mo 14:39 First Quarter
    05  We 08:45 Moon-Beehive: 4° N
    07  Fr 00:30 Moon-Regulus: 0.8° N
    07  Fr 05:14 Moon Ascending Node
    07  Fr 16:58 Jupiter Opposition from the Sun
    10  Mo 17:20 Moon-Jupiter: 2.4° S
    11  Tu 02:08 Full Moon
    14  Fr 01:43 Uranus Conjunction with the Sun
    15  Sa 06:05 Moon Apogee: 405500 km
    16  Su 14:39 Moon-Saturn: 3.6° S
    17  Mo 09:12 Moon South Dec.: 19.1° S
    19  We 05:57 Last Quarter
    20  Th 01:46 Mercury Inferior Conjunction with the Sun
    21  Fr 04:16 Mars-Pleiades: 3.5° S
    21  Fr 18:30 Moon Descending Node
    22  Sa 07:40 Lyrid Meteor Shower: ZHR = 20
    23  Su 13:59 Moon-Venus: 5.3° N
    26  We 08:16 New Moon
    27  Th 12:18 Moon Perigee: 359300 km
    28  Fr 13:20 Moon-Aldebaran: 0.5° S
    30  Su 09:33 Moon North Dec.: 19.2° N
May 01  Mo  Venus: 39.9° W

April 2017 Calendar

     LU                  Ephemeris of Sky Events for Interlochen/TC
April, 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| 07:23a  08:10p  12:47 | 09:15p  06:18a |      Set  01:43a   30%|
+------+-----------------------+----------------+-----------------------+
|Sun  2| 07:21a  08:12p  12:50 | 09:16p  06:16a |      Set  02:44a   41%|
|Mon  3| 07:19a  08:13p  12:53 | 09:18p  06:14a |F Qtr Set  03:38a   53%|
|Tue  4| 07:17a  08:14p  12:56 | 09:19p  06:12a |      Set  04:25a   63%|
|Wed  5| 07:15a  08:15p  12:59 | 09:21p  06:10a |      Set  05:05a   74%|
|Thu  6| 07:14a  08:17p  13:02 | 09:22p  06:08a |      Set  05:40a   82%|
|Fri  7| 07:12a  08:18p  13:06 | 09:24p  06:06a |      Set  06:11a   90%|
|Sat  8| 07:10a  08:19p  13:09 | 09:25p  06:04a |      Set  06:40a   95%|
+------+-----------------------+----------------+-----------------------+
|Sun  9| 07:08a  08:20p  13:12 | 09:27p  06:02a |      Set  07:08a   98%|
|Mon 10| 07:06a  08:21p  13:15 | 09:28p  06:00a |      Set  07:36a  100%|
|Tue 11| 07:05a  08:23p  13:18 | 09:29p  05:58a |Full  Rise 08:54p   99%|
|Wed 12| 07:03a  08:24p  13:21 | 09:31p  05:56a |      Rise 09:54p   97%|
|Thu 13| 07:01a  08:25p  13:24 | 09:32p  05:54a |      Rise 10:52p   93%|
|Fri 14| 06:59a  08:26p  13:27 | 09:34p  05:52a |      Rise 11:49p   87%|
|Sat 15| 06:58a  08:28p  13:30 | 09:35p  05:50a |      Rise 12:43a   80%|
+------+-----------------------+----------------+-----------------------+
|Sun 16| 06:56a  08:29p  13:33 | 09:37p  05:48a |      Rise 01:34a   72%|
|Mon 17| 06:54a  08:30p  13:36 | 09:38p  05:46a |      Rise 02:22a   64%|
|Tue 18| 06:52a  08:31p  13:39 | 09:40p  05:44a |      Rise 03:05a   54%|
|Wed 19| 06:51a  08:33p  13:41 | 09:41p  05:42a |L Qtr Rise 03:45a   44%|
|Thu 20| 06:49a  08:34p  13:44 | 09:43p  05:40a |      Rise 04:21a   34%|
|Fri 21| 06:47a  08:35p  13:47 | 09:44p  05:39a |      Rise 04:55a   25%|
|Sat 22| 06:46a  08:36p  13:50 | 09:46p  05:37a |      Rise 05:27a   16%|
+------+-----------------------+----------------+-----------------------+
|Sun 23| 06:44a  08:38p  13:53 | 09:48p  05:35a |      Rise 05:59a    9%|
|Mon 24| 06:43a  08:39p  13:56 | 09:49p  05:33a |      Rise 06:33a    3%|
|Tue 25| 06:41a  08:40p  13:59 | 09:51p  05:31a |      Rise 07:08a    1%|
|Wed 26| 06:39a  08:41p  14:01 | 09:52p  05:29a |New   Set  09:01p    1%|
|Thu 27| 06:38a  08:43p  14:04 | 09:54p  05:27a |      Set  10:16p    4%|
|Fri 28| 06:36a  08:44p  14:07 | 09:55p  05:25a |      Set  11:29p    9%|
|Sat 29| 06:35a  08:45p  14:10 | 09:57p  05:23a |      Set  12:35a   17%|
+------+-----------------------+----------------+-----------------------+
|Sun 30| 06:33a  08:46p  14:13 | 09:58p  05:22a |      Set  01:34a   27%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

03/30/2017 – Ephemeris – Have you ever seen zodiacal light?

March 30, 2017 Comments off

Ephemeris for Thursday, March 30th.  The Sun will rise at 7:26.  It’ll be up for 12 hours and 41 minutes, setting at 8:07.  The Moon, 3 days past new, will set at 11:23 this evening.

After you spot the moon tonight, hang around outside at the end of astronomical twilight, about 9:50 p.m. look to the west at Taurus the bull and Gemini, trying to block out the Moon.  Then broaden your gaze.  There will be a very faint triangular glow with broad base at the horizon leaning a bit to the left, with its apex near the V of the face of Taurus the bull and the bright star Aldebaran to the right of Orion.  This glow is called Zodiacal Light, caused by the reflected sunlight off a cloud of dust located in the plane of the solar system.  Most of the large bodies of the solar system orbit the sun close to a single plane.  Zodiacal Light is best seen on spring evenings and autumn mornings where it tilts to the right.

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

Addendum

Zodiacal Light and Comet Hale-Bopp April 1997

Zodiacal Light and Comet Hale-Bopp April 1997. My image.

03/29/2017 – Ephemeris – It’s Wednesday, do you know where your bright planets are?

March 29, 2017 Comments off

Ephemeris for Wednesday, March 29th.  The Sun will rise at 7:28.  It’ll be up for 12 hours and 38 minutes, setting at 8:06.  The Moon, 2 days past new, will set at 10:10 this evening.

In the evening sky tonight, replacing Venus will be the elusive planet Mercury.   This tiny planet might be seen to the upper right of the Sun’s setting point starting about 9 p.m.  It will set at 9:49 p.m.  Mars is still hanging on, in the west, and will set at 11:10 p.m.  The thin sliver of a crescent Moon is seen left of and above Mercury and Below Mars tonight.  This might be a good time to spot Earth shine on it’s night side.  Jupiter will rise in the east at 8:47 p.m. a half hour before the star Spica, which it will be seen to hang out with this year.  Jupiter will be still seen in the morning sky low in the southwest at 6 a.m.  Saturn at the same time is in the south above the Teapot figure of Sagittarius.  It will rise tomorrow at 2:33 a.m. in the east-southeast.

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

Addendum

Evening twilight planets

Mercury, Mars and the Moon low in the west at 9 p.m. March 29, 2017. Note the Moon as seen below is a thin crescent which cannot be displayed properly at this scale. Created using Stellarium.

Thin crescent Moon

The thin crescent Moon at 9 p.m. March 29, 2017. Created using Hallo Northern Sky. The program does not have the capability to show earth shine to fill out the rest of the sphere which may be detected with the naked eye or in binoculars.

Jupiter rising

Jupiter low in the east-southeast at 10 p.m. tonight, March 28, 2017. Created using Stellarium.

Jupiter and its moons

Jupiter and its moons tonight March 29, 2017 at 10 p.m. Created using Cartes du Ciel (Sky Charts).

Morning planets and stars

Jupiter and Saturn with the morning constellations of summer at 6 a.m. tomorrow morning March 30, 2017. Created using Stellarium.

Saturn and moons

Saturn and its moons at 6 a.m. March 30, 2017. It is shown at the same scale as Jupiter above. Created using Cartes du Ciel (Sky Charts).

Planets and Moon at sunset and sunrise of a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 29, 2017. The night ends on the left with sunrise on March 30. Click on the image to enlarge. Created using my LookingUp program.

03/28/2017 – Ephemeris – Mercury is visible in the evening sky now

March 28, 2017 Comments off

Ephemeris for Tuesday, March 28th. The Sun will rise at 7:30. It’ll be up for 12 hours and 35 minutes, setting at 8:05. The Moon, 1 day past new, will set at 8:56 this evening.

Mercury is in the evening sky now for it’s spring appearance. Mercury is best seen when it’s near its farthest from the Sun on spring evenings and autumn mornings. Mercury will reach its greatest elongation east of the Sun this coming Saturday with a 19 degree angle of separation from the Sun. This tiny planet is brighter before eastern elongating than after it. I find that the optimal time to look for Mercury is about 45 minutes after sunset. That makes it about 8:50 p.m. At that time Mercury will be low in the west only 9 degrees above the horizon. That’s a bit less than the width of a fist held at arm’s length above the lake or sea horizon, or the base of distant trees that are on your level. Mercury will be visible for about a week or so.

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

Addendum

Mercury near the western horizon at 8:50 p.m. or 45 minutes after sunset. Also shown is its orbit as it appears tonight. The Moon and Uranus are not actually visible in the twilight glare. Mars will be visible a bit later. The Moon will appear between Mercury and Mars tomorrow night. Created using Stellarium.

03/27/2017 – Ephemeris – 5 more new moons before the Great American Total Solar Eclipse!

March 27, 2017 Comments off

Ephemeris for Monday, March 27th.  The Sun will rise at 7:32.  It’ll be up for 12 hours and 31 minutes, setting at 8:04.  The Moon is new today, and won’t be visible.

The Moon will be officially new at 10:57 this evening.  Later this year there will occur at total solar eclipse visible from a narrow path the crosses the United States from Oregon to South Carolina.  It will cross the cities of Casper Wyoming, Kansas City, just south of St Louis, Carbondale, Illinois; Nashville, Columbia and Charleston South Carolina.  Carbondale is about the closest spot to us at about 600 miles.  We will see about 75-80 percent of the Sun blocked by the Moon here in northern Michigan.  The is generally a solar eclipse about every six new moons, the exception is an occasional solar eclipse on two consecutive new moons, except they will occur in opposite polar regions and are rarely total.  The Moon’s orbit is tilted by 5° to the Sun’s path.  This time the Moon is way south of the Sun.

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

Addendum

August 21, 2017 Total Solar Eclipse Path of Totality

A screen cap of the map showing the path of totality of the August 21, 2017 total solar eclipse from NASA’s eclipse page. Credit: NASA and Google Maps.

The points are GE greatest eclipse, path width 71.27 miles (114.7 km); and GD greatest duration of totality, 2 minutes and 40.2 seconds.

Eclipse shadow animation

An animation of the Moon’s shadow as it will cross the Earth’s surface August 21, 2017. Credit A.T. Sinclair/NASA

NASA’s Eclipse page:  https://eclipse2017.nasa.gov/

Solar Corona

The solar corona displayed during the July 10, 1072 total solar eclipse from Prince Edward Island. Credit Bob Moler.

Diamond Ring

Diamond ring at the end of totality of the total solar eclipse July 10, 1972. Credit Bob Moler.

Baily's Beads

Baily’s Beads – sunlight streaming through the valleys at the edge of the Moon at the end of totality, March 7, 1970, outside Bladenboro NC. Credit Bob Moler.

On May 5th, I’ll be giving a talk about the upcoming total solar eclipse.  How to enjoy its partial phases here and along the path of totality.

 

03/24/2017 – Ephemeris – Finding Leo

March 24, 2017 Comments off

Ephemeris for Friday, March 24th.  The Sun will rise at 7:37.  It’ll be up for 12 hours and 22 minutes, setting at 8:00.  The Moon, 3 days before new, will rise at 6:24 tomorrow morning.

At 10 p.m. the spring constellation of Leo the lion will be high in the east-southeast.  It can be found by locating the Big Dipper high in the northeast and imagining that a hole were drilled in the bowl to let the water leak out.  It would drip on the back of this giant cat.  The Lion is standing or lying facing westward.  His head and mane are seen in the stars as a backwards question mark.  This group of stars is also called the sickle.  The bright star Regulus is at the bottom, the dot at the bottom of the question mark.  A triangle of stars, to the left of Regulus, is the lion’s haunches.  Leo contains some nice galaxies visible in moderate sized telescopes.  The stars in Leo’s part of the sky are sparser than those in the winter sky.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Add info on Mercury in the evening sky.

Addendum

Leaky Dipper drips on Leo.

Leaky Big Dipper drips on Leo. Created using mu LookingUp program.

Ursa Major and Leo

Ursa Major with the Big Dipper in her hind end and Leo. Created using Stellarium and GIMP.

03/23/2017 – Ephemeris – a single headed Hydra

March 23, 2017 Comments off

Ephemeris for Thursday, March 23rd.  The Sun will rise at 7:39.  It’ll be up for 12 hours and 19 minutes, setting at 7:59.  The Moon, 3 days past last quarter, will rise at 5:48 tomorrow morning.

In the southern evening sky can be found the constellation of Hydra the water snake.  Unlike the mythical monster Hercules fought of the same name this Hydra has but one head, which is its most distinctive part.  At 9 p.m. look to the south.  The head of Hydra is located directly to the left of Procyon the bright star in Orion’s little dog Canis Minor, and to the right of the star Regulus in Leo.  Hydra’s head is a small distinctive group of 6 stars that make a loop and the snake’s slightly drooping head.  At that time the sinuous body of Hydra sinks below the horizon in the southeast.  As it gets later in the evening the rest of Hydra’s body will slither to just above the southeastern horizon below the planet Jupiter this year and the bright star Spica in the constellation of Virgo.

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

Addendum

Hydra

Finding Hydra animation for 9 p.m. March 23rd 2017. Created using Stellarium.  Click on image to enlarge.

03/22/2017 – Ephemeris – Wednesday is bright planet day but we seem to be missing one of them

March 22, 2017 Comments off

Ephemeris for Wednesday, March 22nd.  The Sun will rise at 7:41.  It’ll be up for 12 hours and 16 minutes, setting at 7:57.  The Moon, 2 days past last quarter, will rise at 5:09 tomorrow morning.

It’s still dark enough to see the morning planets again during these Ephemeris play times.  But it won’t last.  Jupiter will be seen in the morning in the southwest above the star Spica.  It will rise tonight at 9:19 p.m. in the East.  Saturn can be glimpsed this morning above the Teapot figure of Sagittarius in the south.  It will rise tomorrow at 3 a.m. in the east-southeast.  The crescent Moon will be in the east-southeast.  In the evening sky tonight Venus is essentially gone, just 3 days from passing inferior conjunction, it might be seen to the upper right of the Sun’s setting point.  I once spotted it this close to conjunction in the bright twilight.  It will set at 8:35 p.m.  Mars is still hanging on, in the west, and will set at 11:11 p.m.

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

Addendum

Morning planets

Jupiter, Saturn and the crescent Moon at 7 a.m. this morning March 22, 2017. Created using Stellarium.

Venus 15 minutes after sunset

Venus at 15 minutes after sunset on a flat horizon 3 days before inferior conjunction from 45 degrees north latitude. Venus is seen at 3 degrees, 24 minutes above the horizon and practically invisible. Mercury is getting ready for its appearance in the west next week. We will visit it in more detail on Friday.  Created using Stellarium.

Jupiter rising

Jupiter rising and the constellations of winter and spring at 10 p.m. this evening March 22, 2017. Created using Stellarium.

Telescopic Jupiter

Jupiter and its moons at 7 a.m. and 10 p.m. today, March 22, 2017. orientation of Jupiter is as it appears on the sky at those times. Created using Cartes du Ciel (Sky Charts).

Saturn and its moons

Saturn and its moons at 7 a.m. March 22, 2017. It is shown at the same scale as Jupiter above. Created using Cartes du Ciel (Sky Charts).

Binocular Moon

The waning crescent Moon at 7 a.m. as it might be seen in binoculars. Created using Stellarium.

Planets and Moon at sunset and sunrise of a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 22, 2017. The night ends on the left with sunrise on March 23. Note that Venus is visible at both sunrise and sunset at least on these charts. Click on image to enlarge. Created using my LookingUp program.

03/21/2017 – Ephemeris – Let’s find Cancer the crab

March 21, 2017 Comments off

Ephemeris for Tuesday, March 21st.  The Sun will rise at 7:43.  It’ll be up for 12 hours and 13 minutes, setting at 7:56.  The Moon, 1 day past last quarter, will rise at 4:26 tomorrow morning.

At 10 this evening, the faint constellation, and member of the Zodiac, Cancer the crab is located in the south half way between the bright stars Castor and Pollux of the constellation Gemini, high in the south and the bright star Regulus in Leo the lion in the southeast.  Cancer is very dim, looking like an upside-down Y if it’s stars can be made out.  In the center of Cancer is a fuzzy spot to the unaided eye.  In binoculars or a low power telescope this fuzzy spot becomes a cluster of stars.  It is the Beehive cluster.  At 577 light years away, according to the latest measurements, it is one of the closest star clusters, but more distant than the Pleiades and Hyades the face of Taurus the bull off in the west.

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

Addendum

Cancer the Crab

Cancer the crab finder chart. Note the beehive cluster, also known to amateur astronomers as M44, along with other catalog names. Created using Stellarium and GIMP.

The Beehive

The Beehive star cluster, M44. Its ancient name was the Praesepe or manger when glimpsed by the naked eye. Created using Cartes du Ciel (Skycharts)

03/20/2017 – Ephemeris – Spring starts today!

March 20, 2017 Comments off

Ephemeris for Monday, March 20th.  The Sun will rise at 7:45.  It’ll be up for 12 hours and 10 minutes, setting at 7:55.  The Moon, at last quarter today, will rise at 3:39 tomorrow morning.

This morning, at 6:29 (10:29 UT) the sun crosses overhead at the earth’s equator as it appears to head north, starting for us the season of spring.  It’s the vernal equinox.  As you can tell from my intro, we’re already above 12 hours of daylight, and we’ll add another 3 plus hours of daylight before summer begins in three months.  We are already adding about 3 minutes a day of daylight to that goal now, the maximum rate.  With the Sun out longer and its ascension higher in the sky each day, it is rapidly adding energy to the northern hemisphere.  We don’t feel that immediately.  While the land rapidly absorbs heat, the oceans and lakes, especially the Great Lakes are a big heat sink, taking a very long time to warm up.

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

Addendum

This March equinox also is the beginning of autumn for folks south of the equator.

Earth near equinox

Image from the DISCOVR satellite in halo orbit at the Earth-Sun L1 point, nearly a million miles (1.6 million km) sunward of the Earth. as of March 17, 2017. As usual Michigan is covered by a cloud.  Credit NOAA/NASA.