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Ephemeris: 04/09/2025 – Taking our weekly look at the whereabouts of the naked-eye planets

April 9, 2025 Comments off

This is Ephemeris for Wednesday, April 9th. Today the Sun will be up for 13 hours and 12 minutes, setting at 8:20, and it will rise tomorrow at 7:06. The Moon, 3 days before full, will set at 6:13 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. At 9 PM this evening just two of the five naked eye planets will be out. Jupiter, now becomes the brightest evening planet, our substitute evening star if you will. It will be high in the west at 9 PM. Below it is the bright star Aldebaran. To its lower left, the great constellation of Orion. The rapidly fading Mars, with its distinctive reddish hue, is high in the south-southwest, in line with the stars Castor and Pollux in Gemini above right of it. By 6 AM Venus will be seen very low in the east, as the Morning Star,. It will require a low eastern horizon. It should be visible until about 6:45. Saturn should be visible in the morning by the end of the month.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Looking into the west-southwestern sky at 9 pm tonight, Jupiter and Mars are hanging out with the winter stars. And Jupiter, at least, will follow them into the bright twilight in a month or so. Mars will continue its eastward trek from Gemini into Cancer in the next month. Created using Stellarium.
The Moon tonight, 3 days before full. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus, the returning Morning Star, low in the east at 6:30 AM. Created using Stellarium.
Telescopic Jupiter and Venus (north up) as it would be seen in a small telescope with the same magnification. Jupiter is shown for tonight, 9 PM, April 9, 2025. Its apparent diameter is 35.3″. Mars is 7.7″ in diameter, too small to be shown here. My lower size limit is 10″. Venus is shown in the morning of the 10th. Its apparent diameter is 35.3″, and is 10.8% iluminated. Planetary surface detail is more subtle than shown here. The ” means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on April 9, 2025. The night ends on the left with sunrise on the 10th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, April 9th and 10th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , ,

Ephemeris: 04/08/2025 – A look at Proxima Centauri

April 8, 2025 Comments off

This is Ephemeris for Tuesday, April 8th. Today the Sun will be up for 13 hours and 9 minutes, setting at 8:19, and it will rise tomorrow at 7:08. The Moon, halfway from first quarter to full, will set at 5:57 tomorrow morning.

The nearest star to our Sun is a triple star system called Alpha Centauri or Rigil Kentaurus. It is in the skies of the Southern Hemisphere, but visible from the far southern parts of the United States. I’ve seen it from the Florida Keys and also from the latitude of the Big Island of Hawai’i. The closest member of that group this is a star we call Proxima Centauri or just Proxima for short. It is not visible to the naked eye. It is a red dwarf star maybe 12% the Sun’s mass, and at 11th magnitude. Proxima would be tough to spot with a pair of binoculars in a region of the sky which is filled with stars because it’s in the band of the Milky Way. Alpha Centauri, itself, is located near the Southern Cross, the farthest of the two bright stars to the east of it.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Alpha Centauri (Rigil Kentaurus) finder using the Southern Cross as seen from approximately 20 degrees north latitude, where the Southern Cross just clears the southern horizon on late spring evenings. Created using Stellarium, LibreOffice Draw, and GIMP.
Alpha Centauri (Rigil Kentaurus) finder using the Southern Cross
The star field containing Proxima Centauri, including Alpha and Beta Centauri. Hadar (Beta Centauri) is itself a triple star system, but 361 light years away. Image credit: Skatebiker at English Wikipedia, annotations, except for the Proxima finder circle, by the author.
Categories: Ephemeris Program, Stars Tags: , , , , ,

Ephemeris: 04/07/2025 – Does the nearest star to our Sun have a habitable planet?

April 7, 2025 Comments off

This is Ephemeris for Monday, April 7th. Today the Sun will be up for 13 hours and 6 minutes, setting at 8:18, and it will rise tomorrow at 7:10. The Moon, 3 days past first quarter, will set at 5:38 tomorrow morning.

The closest star to our sun is Proxima Centauri which is a small member of the Alpha Centauri star system. It is a red dwarf star and has, we think, at least three planets. They are designated b, c and d. And right now “c” is questionable. At least one of these planets is in the habitable zone of the star, based on the amount of heat this little star gives off. So these planets all quite close to the star, and the problem with Proxima and with most red dwarf stars is that they create a great number of what we call solar flares. When the Earth gets hit by a solar flare from 93 million miles it causes the Northern Lights and causes X-rays to flood the Earth which is mostly shielded by the ozone in our atmosphere. These planets are much closer to their star.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

A diagram of the Proxima Centauri planetary system as we think we know it now
This is a diagram of the Proxima Centauri planetary system as we think we know it now. The diagram assumes circular orbits. The planets are labeled in the order of being found, even if not confirmed, which is why b has a larger orbit than d, all of which have smaller orbits than c. The only confirmed planet is b, which orbits the star in 11 days, and lies at 4.7 million miles (7.5 million kilometers) from it. The distance units are in AU, which are astronomical units, a standard within planetary systems. One AU equals the distance of the Earth to the Sun, therefore Proxima Centauri c has an orbit about the size of Mars’ orbit of the Sun. Instead of taking a bit less than two years to orbit the star like Mars, it takes over five years. Credit: Universe Space Tech.
The star field containing Proxima Centauri
The star field containing Proxima Centauri, including Alpha and Beta Centauri. Hadar (Beta Centauri) is itself a triple star system, but 361 light years away. Image credit: Skatebiker at English Wikipedia, annotations, except for the Proxima finder circle, by the author.
Categories: Ephemeris Program, Exoplanets Tags:

Ephemeris: 04/04/2025 – GTAS Meeting tonight – Astronomy Advancement Outside the Western World

April 4, 2025 Comments off

This is Ephemeris for Friday, April 4th. Today the Sun will be up for 12 hours and 57 minutes, setting at 8:14, and it will rise tomorrow at 7:15. The Moon, at first quarter today, will set at 4:12 tomorrow morning.

The Grand Traverse Astronomical Society will host its April meeting tonight at 8 PM at Northwestern Michigan College’s Joseph H Rogers Observatory. The talk for the evening will be given by Grace Kolbusz, with the student astronomy club at Northwestern Michigan College, will present the program titled Astronomy Advancement Outside the Western World. After the meeting, weather permitting, there will be viewing of the Moon and Jupiter and whatever we can find in the twilight. The observatory is located on Birmley Rd. South of Traverse City between Garfield and Keystone roads. The meeting will also be available via Zoom. Instructions to join the meeting will be on the society’s website, gtastro.org.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Instruments from the ancient Beijing observatory seen against the background backdrop of the modern architecture of the city.
Instruments from the ancient Beijing observatory seen against the backdrop of the modern architecture of the city.

All I know about Grace’s talk is the title. It conjures up astronomy of different cultures, perhaps those of India, China or even the Maya in Central America. In the past I have delved with my December programs, for the GTAS, into ancient astronomies of other cultures. I’ve looked at the Egyptians, Babylonians and the Greeks. And dabbled a little bit with the Mayan culture in their studies of the motions of the planet Venus. So I’m interested in what she comes up with, so I don’t overlap.

Categories: Ephemeris Program, GTAS Outreach Event

Ephemeris: 04/03/2025 – Blue Ghost’s two week long cold night

April 3, 2025 Comments off

This is Ephemeris for Thursday, April 3rd. Today the Sun will be up for 12 hours and 53 minutes, setting at 8:13, and it will rise tomorrow at 7:17. The Moon, 1 day before first quarter, will set at 3:23 tomorrow morning.

During the last lunar day the Blue Ghost Lander spend its time from little after sunrise until a little after sunset investigating the surface of the Moon at the lunar Sea of Crises or Mare Crisium. It wasn’t expected to survive the two-week-long night. It wasn’t expected to because it had no internal heating and at night the temperatures on the Moon can drop to down to minus 208° F, or a little bit more on the night side. During the day the temperature gets up to 250° which is pretty hot for some of the electronics. But what really kills a Lander is at night where they can’t recharge the batteries and the batteries drop in temperature to 200° below zero for two weeks. They generally do not survive.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

The last little bit of sunlight provided by the setting sun photographed by the Firefly Aerospace's Blue Ghost Lander with the overexposed crescent Earth above, and Venus shining at a 1 o'clock position somewhat lower.
The last little bit of sunlight provided by the setting sun photographed by the Firefly Aerospace’s Blue Ghost Lander with the overexposed crescent Earth above, and Venus shining at a 1 o’clock position somewhat lower. The reason for these sunset and post sunset images is to find elusive dust suspended as the Moon’s “atmosphere” described by Eugene Cernan on the Apollo 17 mission. Credit: NASA/Firefly Aerospace via AP.
Categories: Ephemeris Program, Space exploration, The Moon Tags:

Ephemeris: 04/02/2025 – Let’s take our weekly look at the whereabouts of the naked-eye planets

April 2, 2025 Comments off

This is Bob Moler with Ephemeris for Wednesday, April 2nd. Today the Sun will be up for 12 hours and 50 minutes, setting at 8:12, and it will rise tomorrow at 7:19. The Moon, 2 days before first quarter, will set at 2:19 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. At 9 PM this evening just two of the five naked eye planets will be out. Jupiter, now becomes the brightest evening planet, our substitute evening star if you will. It will be high in the west-southwest at 9 PM. Below it is the bright star Aldebaran and above it tonight will be the crescent Moon. To its lower left, the great constellation of Orion. The rapidly fading Mars, with its distinctive reddish hue, is high in the south, with the stars Castor and Pollux in Gemini above it. Venus may become visible in a few days low in the east starting as early as 6:30 AM. It will require a low eastern horizon, since it will be very low in the sky.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Jupiter and Mars tonight.
Looking into the southwestern sky at 9 pm tonight, Jupiter and Mars are hanging out with the winter stars. And Jupiter, at least, will follow them into the bright twilight in a month or so. Mars will continue its eastward trek from Gemini into Cancer in the next month. Created using Stellarium,
The Moon tonight, 2 days before first quarter. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Jupiter (north up) as it would be seen in a small telescope. Jupiter is shown for tonight, 9 PM, April 2, 2025.
Telescopic Jupiter (north up) as it would be seen in a small telescope. Jupiter is shown for tonight, 9 PM, April 2, 2025. Its apparent diameter is 35.9″. Mars is 8.1″ in diameter, too small to be shown here. My lower size limit is 10″. Planetary surface detail is more subtle than shown here. The ” means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on April 2, 2025. The night ends on the left with sunrise on the 3rd. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, April 2nd and 3rd, 2025
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, April 2nd and 3rd, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 04/01/2025 – Previewing April 2025 skies

April 1, 2025 Comments off

This is Ephemeris for April Fools’ Day, Tuesday, April 1st. Today the Sun will be up for 12 hours and 47 minutes, setting at 8:10, and it will rise tomorrow at 7:21. The Moon, halfway from new to first quarter, will set at 1:03 tomorrow morning.

The second quarter of the year begins today. Daylight hours in the Interlochen/Traverse City area and will increase from 12 hours and 47 minutes today to 14 hours 13 minutes on the 30th as spring really takes hold. The altitude, or angle, of the sun above the southern horizon at local noon will be 50 degrees today and will ascend to 60 degrees on April 3 The altitude of the Sun in the Straits area will be a degree lower. The actual time of local apparent noon at mid-month for the Interlochen/Traverse City area, when the sun passes due south, will be about 1:42 p.m. Jupiter and Mars will still be our evening planets this month. The Pleiades, tonight, will be just below the crescent Moon.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

April Evening Star Chart

Star Chart for April 2025 (10 p.m. EDT, April 15, 2025).
Star Chart for April 2025 (10 p.m. EDT, April 15, 2025). Click or tap on the image to enlarge it. Created using my LookingUp program.

The planets and stars are plotted for the 15th at 10 PM EST in the evening and 5 AM 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). To duplicate the star positions on a planisphere (rotating star finder) you may have to set it to 45 minutes or one hour 45 minutes (Daylight Time) earlier than the current time.

Note the chart times of 10 PM and 6 AM are for the 15th and 16th. For each week before these dates, add ½ hour (28 minutes if you’re picky). For each week after, subtract ½ hour. Planet positions on dates other than the 15/16th can be found in the Wednesday planet posts on this blog.

April Morning Star Chart

Star Chart for April mornings, 2025(5 a.m. EDT, April 16, 2025)
Star Chart for April mornings, 2025(5 a.m. EDT, April 16, 2025). Click or tap on the image to enlarge it. 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.
2025-04-01 5h42m 6h19m 21h18m 21h54m – 5h42m 0.20
2025-04-02 5h40m 6h17m 21h19m 21h56m 1h03m 5h40m 0.30
2025-04-03 5h38m 6h15m 21h21m 21h57m 2h20m 5h38m 0.40
2025-04-04 5h36m 6h13m 21h22m 21h59m 3h23m 5h36m 0.51
2025-04-05 5h34m 6h11m 21h23m 22h01m 4h12m 5h34m 0.62
2025-04-06 5h32m 6h09m 21h25m 22h02m 4h49m 5h32m 0.71
2025-04-07 5h29m 6h07m 21h26m 22h04m 5h17m 5h29m 0.80
2025-04-08 5h27m 6h05m 21h28m 22h06m – – 0.87
2025-04-09 5h25m 6h03m 21h29m 22h07m – – 0.93
2025-04-10 5h23m 6h01m 21h31m 22h09m – – 0.97
2025-04-11 5h21m 5h59m 21h32m 22h11m – – 0.99
2025-04-12 5h18m 5h57m 21h34m 22h12m – – 1.00
2025-04-13 5h16m 5h55m 21h35m 22h14m – – 0.99
2025-04-14 5h14m 5h53m 21h36m 22h16m 22h16m 22h37m 0.96
2025-04-15 5h12m 5h51m 21h38m 22h17m 22h17m 23h43m 0.91
2025-04-16 5h09m 5h49m 21h39m 22h19m 22h19m – 0.85
2025-04-17 5h07m 5h47m 21h41m 22h21m 22h21m 0h48m 0.78
2025-04-18 5h05m 5h45m 21h42m 22h23m 22h23m 1h48m 0.69
2025-04-19 5h03m 5h43m 21h44m 22h25m 22h25m 2h40m 0.59
2025-04-20 5h01m 5h41m 21h45m 22h26m 22h26m 3h23m 0.49
2025-04-21 4h58m 5h39m 21h47m 22h28m 22h28m 3h57m 0.38
2025-04-22 4h56m 5h38m 21h49m 22h30m 22h30m 4h25m 0.28
2025-04-23 4h54m 5h36m 21h50m 22h32m 22h32m 4h48m 0.18
2025-04-24 4h52m 5h34m 21h52m 22h34m 22h34m 4h52m 0.10
2025-04-25 4h50m 5h32m 21h53m 22h36m 22h36m 4h50m 0.04
2025-04-26 4h47m 5h30m 21h55m 22h37m 22h37m 4h47m 0.01
2025-04-27 4h45m 5h28m 21h56m 22h39m 22h39m 4h45m 0.00
2025-04-28 4h43m 5h26m 21h58m 22h41m 22h41m 4h43m 0.03
2025-04-29 4h41m 5h25m 21h59m 22h43m 23h56m 4h41m 0.09
2025-04-30 4h39m 5h23m 22h01m 22h45m – 4h39m 0.16

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  Tu            Venus: 16.3° W
     1  Tu   4:28 PM  Moon-Pleiades: 0.6° S
     3  Th   6:15 PM  Moon North Dec.: 28.7° N
     4  Fr  10:14 PM  First Quarter
     5  Sa  12:46 PM  Moon-Pollux: 2.1° N
     5  Sa   3:04 PM  Moon-Mars: 2.3° S
     6  Su  12:44 PM  Moon-Beehive: 2.8° S
     8  Tu   7:51 AM  Moon-Regulus: 2.4° S
    10  Th   8:19 AM  Mercury-Saturn: 2.1° N
    10  Th   3:56 PM  Moon Descending Node
    12  Sa   8:22 PM  Full Moon
    12  Sa   9:39 PM  Moon-Spica: 0.4° N
    13  Su   6:48 PM  Moon Apogee: 406300 km
    16  We   6:19 PM  Moon-Antares: 0.4° N
    18  Fr   9:24 AM  Moon South Dec.: 28.6° S
    20  Su   9:35 PM  Last Quarter
    21  Mo   2:59 PM  Mercury Elongation: 27.4° W
    22  Tu   8:53 AM  Lyrid Shower: ZHR = 20
    24  Th   9:21 PM  Moon-Venus: 2.4° N
    24  Th  10:23 PM  Moon Ascending Node
    25  Fr  12:15 AM  Moon-Saturn: 2.3° S
    25  Fr   9:05 PM  Moon-Mercury: 4.3° S
    27  Su  12:15 PM  Moon Perigee: 357100 km
    27  Su   3:31 PM  New Moon
    28  Mo   3:27 PM  Venus-Saturn: 3.7° N
    29  Tu   2:35 AM  Moon-Pleiades: 0.5° S
May  1  Th            Venus: 40.9° W

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, 2025    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Tue  1| 07:23a  08:10p  12:47 | 09:15p  06:18a |      Set  01:03a   18%|
|Wed  2| 07:21a  08:12p  12:50 | 09:17p  06:16a |      Set  02:19a   27%|
|Thu  3| 07:19a  08:13p  12:53 | 09:18p  06:14a |      Set  03:23a   38%|
|Fri  4| 07:17a  08:14p  12:57 | 09:19p  06:12a |F Qtr Set  04:12a   49%|
|Sat  5| 07:15a  08:15p  13:00 | 09:21p  06:10a |      Set  04:48a   60%|
+------+-----------------------+----------------+-----------------------+
|Sun  6| 07:13a  08:17p  13:03 | 09:22p  06:08a |      Set  05:16a   69%|
|Mon  7| 07:12a  08:18p  13:06 | 09:24p  06:06a |      Set  05:38a   78%|
|Tue  8| 07:10a  08:19p  13:09 | 09:25p  06:04a |      Set  05:57a   86%|
|Wed  9| 07:08a  08:20p  13:12 | 09:27p  06:02a |      Set  06:13a   92%|
|Thu 10| 07:06a  08:22p  13:15 | 09:28p  06:00a |      Set  06:29a   96%|
|Fri 11| 07:04a  08:23p  13:18 | 09:30p  05:58a |      Set  06:44a   99%|
|Sat 12| 07:03a  08:24p  13:21 | 09:31p  05:56a |Full  Rise 08:25p  100%|
+------+-----------------------+----------------+-----------------------+
|Sun 13| 07:01a  08:25p  13:24 | 09:33p  05:54a |      Rise 09:30p   99%|
|Mon 14| 06:59a  08:27p  13:27 | 09:34p  05:52a |      Rise 10:36p   96%|
|Tue 15| 06:57a  08:28p  13:30 | 09:35p  05:50a |      Rise 11:43p   92%|
|Wed 16| 06:56a  08:29p  13:33 | 09:37p  05:48a |      Rise 12:48a   86%|
|Thu 17| 06:54a  08:30p  13:36 | 09:39p  05:46a |      Rise 01:48a   79%|
|Fri 18| 06:52a  08:32p  13:39 | 09:40p  05:44a |      Rise 02:40a   70%|
|Sat 19| 06:51a  08:33p  13:42 | 09:42p  05:42a |      Rise 03:22a   61%|
+------+-----------------------+----------------+-----------------------+
|Sun 20| 06:49a  08:34p  13:45 | 09:43p  05:40a |L Qtr Rise 03:57a   51%|
|Mon 21| 06:47a  08:35p  13:47 | 09:45p  05:38a |      Rise 04:25a   40%|
|Tue 22| 06:46a  08:37p  13:50 | 09:46p  05:36a |      Rise 04:48a   30%|
|Wed 23| 06:44a  08:38p  13:53 | 09:48p  05:35a |      Rise 05:09a   20%|
|Thu 24| 06:43a  08:39p  13:56 | 09:49p  05:33a |      Rise 05:29a   11%|
|Fri 25| 06:41a  08:40p  13:59 | 09:51p  05:31a |      Rise 05:50a    5%|
|Sat 26| 06:39a  08:42p  14:02 | 09:52p  05:29a |      Rise 06:14a    1%|
+------+-----------------------+----------------+-----------------------+
|Sun 27| 06:38a  08:43p  14:04 | 09:54p  05:27a |New   Set  09:05p    0%|
|Mon 28| 06:36a  08:44p  14:07 | 09:55p  05:25a |      Set  10:33p    2%|
|Tue 29| 06:35a  08:45p  14:10 | 09:57p  05:23a |      Set  11:56p    7%|
|Wed 30| 06:33a  08:46p  14:13 | 09:59p  05:22a |      Set  01:08a   15%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

Generated using my LookingUp for DOS program.

Categories: Ephemeris Program, Month preview Tags: ,

Ephemeris: 03/31/2025 – Finding Leo, the celestial lion

March 31, 2025 Comments off

This is Ephemeris for Monday, March 31st. Today the Sun will be up for 12 hours and 44 minutes, setting at 8:09, and it will rise tomorrow at 7:23. The Moon, 2 days past new, will set at 11:39 this evening.

At 10 p.m. the spring constellation of Leo the lion will be high in the south-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 fewer than those in the winter sky.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

Finding the constellation of Leo the lion by using the Big Dipper. Starting nearly overhead we find the Big Dipper in the constellation Ursa Major. Using the bowl of the dipper, and make believe that somebody drilled a hole through the bottom to let the water fall out. It will fall on the back of Leo, which is high in the south-southeastern sky. The little cross in the second image is the zenith. This is for 10:00 PM on March 30th. Created using my LookingUp app, LibreOffice Draw and GIMP.
The galaxies in the constellation of Leo
The galaxies in the constellation of Leo . The three galaxies near the hind end of Leo: M 65, M 66 and NGC 3628, are collectively known as the Leo Triplet. There are three other Messier galaxies below center of Leo and another Galaxy, NGC 2309 in front of the face of Leo. All these galaxies are about 31 to 35 million light years away.
Categories: Constellations, Ephemeris Program, Observing, Uncategorized Tags: , ,

Ephemeris: 03/28/25 – There’s a partial solar eclipse tomorrow, but not for Michigan

March 28, 2025 Comments off

This is Bob Moler with Ephemeris for Friday, March 28th. Today the Sun will be up for 12 hours and 35 minutes, setting at 8:05, and it will rise tomorrow at 7:28. The Moon, 1 day before new, will rise at 7:29 tomorrow morning.

There will be a partial solar eclipse tomorrow morning which will end about 14 minutes before sunrise for Northwestern Lower Michigan. It will be visible to the east and north of here, including all the way to northern Asia. It belongs to the same eclipse season as our total lunar eclipse two weeks ago. Eclipse seasons occur twice a year and last about 35 days. During that time, since it’s a little bit longer than a lunar month, there will be at least 2 eclipses, one of each kind, lunar and solar. There’s a possibility of three, if there is a central lunar eclipse. Then there can be two partial solar eclipses, one to the extreme north, the other to the extreme south of the Earth. The eclipse seasons slip a bit earlier each year. Last year’s total solar eclipse occurred April 8th.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

A map of tomorrow's partial solar eclipse.
A map of tomorrow’s partial solar eclipse. The Moon’s umbra from which one could see a total solar eclipse falls north of the Earth, so the Moon only partially blocks the Sun’s light in its penumbra. Only the areas within the bounded area will see the eclipse. The big mishapen red Figure 8 are where eclipse events occur at sunrise on the left and sunset on the right. Credit: Fred Espenak, NASA’s Goddard Space Flight Center, With my own explanatory additions.

Categories: Eclipses, Ephemeris Program Tags:

Ephemeris: 03/27/2025 – Cancer the celestial crab

March 27, 2025 Comments off

This is Bob Moler with Ephemeris for Thursday, 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, 2 days before new, will rise at 7:08 tomorrow morning.

At 10 PM, between the stars Castor and Pollux in Gemini high in the southwest and the star Regulus in Leo the Lion in the southeast lies the dimmest constellation of the zodiac, Cancer the crab. To me its 5 brightest stars make an upside down Y. There are the stars in the center of the constellation Asellus Borealis and Asellus Australis, the north and south donkeys. There’s a fuzzy spot between and just west of them called Praesepe, the manger, from which they are eating hay. In binoculars, it resolves into a cluster of stars called the Beehive cluster. We amateur astronomers also know it as M44, the 44th object on 18th century comet hunter Charles Messier’s list of fuzzy objects that might be mistaken for comets.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.

Addendum

An animated finder for Cancer the crab.
An animated finder for Cancer the crab for 10 PM, March 27, 2025. Star intensity has been increased to beyond naked eye visibility to bring out the stars of Cancer, which are quite dim. Click or tap on the image to enlarge it. Created using Stellarium, LibreOffice Draw, and GIMP.
The Beehive Cluster
The Beehive star cluster, M44. Its ancient name was the Praesepe or manger when glimpsed by the naked eye as a fuzzy spot. Created using Cartes du Ciel (Skycharts)

Categories: Constellations, Ephemeris Program, Observing Tags: , , ,