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Ephemeris: 07/26/2023 – Let’s find out where the naked-eye planets have wandered off to this week

July 26, 2023 Comments off

This is Bob Moler with Ephemeris for Wednesday, July 26th. Today the Sun will be up for 14 hours and 53 minutes, setting at 9:15, and it will rise tomorrow at 6:23. The Moon, 1 day past first quarter, will set at 1:08 tomorrow morning. | Let’s find out where the naked-eye planets have wandered off to this week. Venus is our hard to find Evening Star, seen very low in the west in evening twilight by 9:45 pm. It will set at 10:11 pm, Mercury might be spotted to Venus’ right and a bit above. The red planet Mars is pretty much lost in the evening twilight, above and left of Venus. Saturn will rise at 10:38 pm. And by 5:30 am, or a bit less than an hour before sunrise tomorrow, it will appear in the south-southwest, the brightest “star” in that direction. Its above the bright star Fomalhaut, normally the loneliest bright star in the sky. Jupiter will be in the east-southeast at that hour. Jupiter is the brightest star-like object in the morning sky now, near some of the bright stars of a winter’s evening.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Venus, Mercury and Mars in evening twilight at 9:15 pm, about a half hour after sunset. Also shown are what their orbits would look like from Earth’s prospective. In actuality, Mercury and Mars will not be visible in the bright twilight. Created using Stellarium and GIMP.
The Moon, with labels for select features, as it might appear at 10 pm tonight, July 26, 2023. Created using Stellarium, LibreOffice Draw, and GIMP.
Jupiter and Saturn with the bright stars of autumn (Fomalhaut) and winter (Aldebaran, Betelgeuse, and Rigel) evenings at 5:30 am, July 27, 2023. Off-topic: the last reports I’ve seen is that Betelgeuse is acting up again. Four years ago it got dimmer than usual. Now, from the reports I’ve seen, is that it’s brighter than usual. Betelgeuse normally varies a bit in brightness, but these excursions are out of its normal range. Click or tap on the image to enlarge it. Large images like this are sometimes truncated to the right. Enlarging the image will restore the whole image. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope, with the same magnification at 9:45 pm July 26, 2023, for Venus and 5:30 am July 27, 2023, for Jupiter and Saturn. Apparent diameters: Venus 50.30″ and is 9.8% illuminated; Saturn 18.66″, its rings 43.47″; Jupiter 39.28″. Venus now appears larger than Jupiter. Venus, Saturn and Jupiter are approaching us, so their apparent diameters are growing. The ” symbol means seconds of arc (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 July 26, 2023. The night ends on the left with sunrise on the 27th. Click or tap on the image to enlarge it. Large images like this are sometimes truncated to the right. Enlarging the image will restore the whole image. Created using my LookingUp app and GIMP.
Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , , ,

Ephemeris: 07/24/2023 – The Moon appears to wobble a bit

July 24, 2023 Comments off

This is Ephemeris for Monday, July 24th. Today the Sun will be up for 14 hours and 57 minutes, setting at 9:17, and it will rise tomorrow at 6:21. The Moon, 1 day before first quarter, will set at 12:24 tomorrow morning.

The Moon tonight is nearly half illuminated. In binoculars the dark oval spot visible on the Moon’s right edge is the Sea of Crises or Mare Crisium a small dark lava plain. The Moon’s rotation is quite uniform, however its orbit isn’t circular, so the Moon’s motion in its orbit slows as it moves farthest from the Earth, called apogee, and is sped up when closest, at perigee, So its face seems to rock a bit back and forth over the month. It’s an effect called libration. And one way to track that is to note how close the Mare Crisium (Sea of Crises) is to the edge of the Moon. It appears close to the right edge now. A week from now, that sea will appear to move away from the edge. Unfortunately, by then the Moon will be full, and night will soon fall on that little sea.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

The Moon on two dates 8 days apart, showing the apparent wobble or libration of the Moon by the changing position of Mare Crisium (Sea of Crises). Also note that the full moon is larger. It’s a supermoon, for what it’s worth. Created using Virtual Moon Atlas, LibreOffice Draw, and GIMP.
Categories: Concepts, Ephemeris Program, Observing, The Moon Tags:

Ephemeris: 07/20/2023 – How Boötes and Ursa Major got into the sky

July 20, 2023 Comments off

This is Ephemeris for Thursday, July 20th. Today the Sun will be up for 15 hours and 5 minutes, setting at 9:21, and it will rise tomorrow at 6:17. The Moon, 3 days past new, will set at 11:16 this evening.

Seen in high in the west-southwest at 10:30 this evening is the kite shaped constellation of Boötes (pronounced Bo-o-tees) the herdsman. The bright star Arcturus is at the bottom of the kite. It is pointed to by the arc of the handle of the Big Dipper, part of Ursa Major, the Great Bear, over toward the northwest. Boötes represents a young hunter named Arcas, son of Callisto, a beautiful young lady who had the misfortune of being loved by Zeus, the chief of the Greek gods. Zeus’ wife, Hera, found out about it, and since she couldn’t punish Zeus, turned the poor woman into a bear. Arcas, many years later, unaware of the events surrounding his mother’s disappearance, was about to kill the bear when Jupiter intervened and placed them both in the sky to save her. Arcas still pursues her across the sky nightly.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Boötes as Arcas chases Ursa Major as Callisto around the pole of the sky nightly. Created using Stellarium and GIMP.
Arcas and Callisto woodcut
Arcas about to slay the bear by the 17th century artist Baur. Source: University of Virginia Electronic Text Center
Categories: Constellations, Ephemeris Program, Mythology, Observing Tags: ,

Ephemeris: 07/19/2023 – Let’s find out where the naked-eye planets have wandered off to this week

July 19, 2023 Comments off

This is Ephemeris for Wednesday, July 19th. Today the Sun will be up for 15 hours and 7 minutes, setting at 9:22, and it will rise tomorrow at 6:16. The Moon, 2 days past new, will set at 10:55 this evening.

Let’s find out where the naked-eye planets have wandered off to this week. Venus is our blazing Evening Star, seen very low in the west in evening twilight. It will set at 10:31 pm, and by four minutes earlier each night. The red planet Mars is now pretty much lost in the evening twilight. We’ll see it in the morning sky in a few months. Venus too will soon leave the evening sky. Saturn will rise shortly after 11 pm. And by 5:15 am, or an hour before sunrise, it will appear in the south-southwest, the brightest “star” in that direction. It’s above the bright star Fomalhaut, normally the loneliest bright star in the sky. Jupiter will be in the east-southeast at that hour. Jupiter is the brightest star-like object in the morning sky now.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Venus, Mercury and the two-day-old Moon seen low in the west-northwest at 10 pm, about 40 minutes after sunset. Mercury is most likely not visible in the bright twilight. Mid to late summer and early to mid-autumn are difficult times to see the Moon and planets close to the Sun. The opposite is true in the morning sky. Created using Stellarium.
The two-day-old Moon might look like this in binoculars, showing earthshine by the nearly full Earth in its sky. Created using Stellarium and GIMP.
Jupiter and Saturn with two bright stars at 5:15 am, about an hour before sunrise. Fomalhaut will grace our evening skies this autumn, while Aldebaran will appear in late autumn and winter. Click or tap on the image to possibly enlarge it. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope, with the same magnification at 10:00 pm July 19, 2023, for Venus and 5:15 am July 20, 2023, for Jupiter and Saturn. Apparent diameters: Venus 45.30″ and is 15.7% illuminated; Saturn 18.52″, its rings 43.15″; Jupiter 38.48″. Venus now appears larger than Jupiter. Venus, Saturn and Jupiter are approaching us, so their apparent diameters are growing. The ” symbol means seconds of arc (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 July 19, 2023. The night ends on the left with sunrise on the 20th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.

Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 07/18/2023 – Vega, the brightest star of the Summer Triangle

July 18, 2023 Comments off

This is Ephemeris for Tuesday, July 18th. Today the Sun will be up for 15 hours and 9 minutes, setting at 9:23, and it will rise tomorrow at 6:15. The Moon, 1 day past new, will set at 10:30 this evening.

Vega, in the constellation Lyra the harp, is the highest bright star In the east and brightest star of the Summer Triangle also rising in that direction. It is an important and much studied star, first as a standard for brightness for the magnitude scale at almost exactly zero. In 1983 the Infrared Astronomy Satellite, IRAS, discovered an excess of infrared radiation coming from the star. It seems now that there are two orbiting rings around the star, an inner warm ring and an outer cold ring. This is somewhat like the two disks of material the Sun has: The asteroid belt between Mars and Jupiter and the Kuiper belt, beyond Neptune. No planets have yet been discovered around Vega, but I wouldn’t bet against it.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Annimated Lyra finder chart
Animated Lyra finder chart. The lyre image not supplied by Stellarium but is from The World’s Earliest Music by Hermann Smith, Figure 60, A Project Gutenberg E-Book, and captioned “The Chelys or Greek Tortoiseshell Lyre”. Vega is the brightest star in Lyra, and the brightest star of the Summer Triangle. The other stars of the triangle are Deneb and Altair. Click or tap on the image to possibly enlarge it. Created using Stellarium and GIMP.
Vega debris fields
Vega possesses two debris fields, similar to our own solar system’s asteroid and Kuiper belts. Astronomers continue to hunt for planets orbiting Vega, but as of May 2020 none have been confirmed. More info: bit.ly/VegaSystem Credit: NASA/JPL-Caltech.

Categories: Ephemeris Program, Observing, Stars Tags: , ,

07/14/2023 – Ephemeris – Finding Polaris and why it’s important

July 14, 2023 Comments off

This is Bob Moler with Ephemeris for Friday, July 14th. Today the Sun will be up for 15 hours and 16 minutes, setting at 9:26, and it will rise tomorrow at 6:11. The Moon, 3 days before new, will rise at 3:46 tomorrow morning.

The most important star in the night sky, especially if you are lost, is Polaris, also called the North Star or Pole Star. Face Polaris and North is in front of you, East is to the right, west to the left and south will be behind you. To find Polaris, first find the Big Dipper. In the evening. This time of year, it’s hanging by its handle in the northwest, the direction that the sun set at. The two stars at the front of the bowl point to Polaris, which is to the right of it, now. Throughout the night, as the Earth rotates. Polaris will hold its position as all the other stars go around it in a counterclockwise direction. Polaris is at the end of the handle of the Little Dipper. That handle start’s vertically but curves to the left and is made of faint stars.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

A chart from Stellarium showing the Big and Little Dippers, and how the stars at the front of the bowl of the Big Dipper point to Polaris. The lines show asterisms, which are informal constellations. The blue radial grid is the Earth’s longitude and latitude lines projected on the imaginary celestial sphere. The latitude lines on the celestial sphere are called declination lines, and are 10 degrees apart. The lines analogous to longitude are called right ascension lines and are 15 degrees apart to match one hour in Earth’s sidereal rotation. Polaris is nearly at the north pole of the celestial sphere, so as the Earth rotates, it remains nearly stationary. The altitude of Polaris here is nearly 45 degrees, which approximates the latitude of my location of about 44 2/3 degrees north. Created using Stellarium and LibreOffice Draw for the captions.
Categories: Concepts, Ephemeris Program, Observing Tags: , , , ,

07/13/2023 – Ephemeris – How to find Ophiuchus the serpent bearer

July 13, 2023 Comments off

This is Ephemeris for Thursday, July 13th. Today the Sun will be up for 15 hours and 17 minutes, setting at 9:27, and it will rise tomorrow at 6:10. The Moon, halfway from last quarter to new, will rise at 3:04 tomorrow morning.

The red star Antares shines in the south at 11 p.m. In the constellation of Scorpius. In the area of sky above and a little to the left lies a large constellation of faint stars called Ophiuchus, the serpent bearer. The constellation shape is like a large bell, which reminds me of the head, shoulders and arms of a fellow that’s holding the snake-like a weight lifter pulling up a heavy barbell. The serpent he’s holding is Serpens, the only two-part constellation in the heavens. The head rises to Ophiuchus’ right, and the tail extends up to the left. In Greek myth, Ophiuchus represents the great physician Aesculapius, educated by the god Apollo, and the centaur Chiron, who is found in the stars as Sagittarius, now rising below and left of him.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Ophiuchus finder animation for July 13th at 11 pm. Obviously, the image I conjured up doesn’t quite match the constellation art that is part of Stellarium, but that’s the fun of seeing the sky your way. Created using Stellarium and GIMP.
Categories: Constellations, Ephemeris Program, Mythology, Observing Tags: , , , , , ,

07/12/2023 – Ephemeris – Let’s find out where the naked-eye planets have wandered off to this week

July 12, 2023 Comments off

This is Bob Moler with Ephemeris for Wednesday, July 12th. Today the Sun will be up for 15 hours and 19 minutes, setting at 9:27, and it will rise tomorrow at 6:09. The Moon, 3 days past last quarter, will rise at 2:30 tomorrow morning.

Let’s find out where the naked-eye planets have wandered off to this week. Tonight, Venus is our blazing Evening Star, seen very low in the west in evening twilight. It will set at 11:06 pm, and by four minutes earlier each night. The red planet Mars is seen left of and above Venus. It’s the second “star” with the brighter real star Regulus in Leo the lion between it and Venus. Mars is much fainter than Venus and difficult to spot in twilight. Saturn will rise shortly before midnight. And by 5 am tomorrow, will appear in the south, the brightest “star” in that direction. Jupiter will be in the east at that hour. It will appear above and right of the waning crescent Moon at that hour. Jupiter is the brightest star-like object in the morning sky now.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Venus, Regulus and Mars as they might appear tonight, July 12, 2023 at 10:15 or about 45 minutes after sunset. Venus would be about 8 1/2 degrees above a flat horizon. At this time, Venus would appear a bit higher from south of our approximately 45 degrees north latitude, and lower north of here. Created using Stellarium.
A panorama of the morning horizon from northeast to south at 5 am tomorrow morning, or about an hour and a quarter before sunrise. Click or tap on the image to enlarge it.
The Moon as it might appear tomorrow morning, July 13, 2023. The whole Moon might be visible due to earthshine (The nearly full Earth, from the Moon’s perspective, illuminating its night side). Click on the image to enlarge. Created using Stellarium, Libreoffice Draw, and GIMP.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope, with the same magnification at 10:15 pm July 12, 2023, for Venus and 5:00 am July 13, 2023, for Jupiter and Saturn. Apparent diameters: Venus 40.49″ and is 22.0% illuminated; Saturn 18.36″, its rings 42.77″; Jupiter 37.73″. Mars, too small to be represented here, is 4.18″ in diameter. Venus now appears larger than Jupiter. Venus, Saturn and Jupiter are approaching us, so their apparent diameters are growing. Europa is casting its shadow on Jupiter, see the small dot below center on the planet. The ” symbol means seconds of arc (1/3600th of a degree.) Click or tap on the image to enlarge it. 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 July 12, 2023. The night ends on the left with sunrise on the 13th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
Categories: Ephemeris Program, Observing, Planets Tags: , , , ,

07/05/2023 – Ephemeris – Let’s find out where the naked-eye planets have wandered off to this week

July 5, 2023 Comments off

This is Ephemeris for Wednesday, July 5th. Today the Sun will be up for 15 hours and 27 minutes, setting at 9:31, and it will rise tomorrow at 6:04. The Moon, 2 days past full, will rise at 11:49 this evening.

Let’s find out where the naked-eye planets have wandered off to this week. Venus is our blazing Evening Star, seen low in the west most of the evening. It sets tonight at 11:28 pm, and by three minutes earlier each night. The red planet Mars is seen left of and above Venus. And left of Mars is the brighter star Regulus in Leo the lion. Venus is pulling away from Mars now. Mars is much fainter than Venus and difficult to spot in twilight. Saturn will rise shortly after midnight. And by 5:15 am will appear in the south, the brightest “star” in that direction. It will appear above and left of the waning gibbous Moon at that hour. Jupiter will be in the east at that hour. It is the brightest star-like object in the morning sky now.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Venus, Mars and bright star Regulus can be seen low in the west at 10:15 pm EDT, or about 45 minutes after sunset, tonight July 5, 2023. Created using Stellarium.
Jupiter, Saturn and the waning gibbous Moon seen at 5:15 am, about an hour before sunrise tomorrow morning, July 6, 2023. Fomalhaut, the loneliest star in the sky, is also visible. It’s kept company by Saturn for a few years every 30 years. Click or tap on the image to enlarge it. Created using Stellarium.
Waning gibbous Moon with labels as it might be seen at 5:15 am, about one hour before sunrise tomorrow, July 5, 2023. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope, with the same magnification at 10:15 pm July 5, 2023, for Venus and 5:15 am July 6, 2023, for Jupiter and Saturn. Apparent diameters: Venus 36.21″ and is 28.1% illuminated; Saturn 18.18″, its rings 42.35″; Jupiter 37.04″. Mars, too small to be represented here, is 4.18″ in diameter. Venus, Saturn and Jupiter are approaching us, so their apparent diameters are growing. Europa is transiting in front of Jupiter. Normally it would not be visible. The ” symbol means seconds of arc (1/3600th of a degree.) Click or tap on the image to enlarge it. 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 July 5, 2023. The night ends on the left with sunrise on the 6th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.

Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

06/30/2023 – Ephemeris – Previewing July’s skies

June 30, 2023 Comments off

This is Bob Moler with Ephemeris for International Asteroid Day, Friday, June 30th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:32, and it will rise tomorrow at 6:01. The Moon, 3 days before full, will set at 3:45 tomorrow morning.

Let’s preview July’s skies. The Sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 31 minutes tomorrow to 14 hours 42 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the Sun at local noon, when it is due south, will decrease from 68 degrees now to 63 degrees at month’s end. The Sun will be a degree lower in the Straits area. Despite the warmth, the Earth will reach its greatest distance from the Sun next Thursday, the 6th. On that day, the Earth will reach 94.5 million miles (152.1 million kilometers) from the Sun.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

July Evening Star Chart

Star Chart for July 2023 (11 p.m. EDT, July 15, 2023). Created using my LookingUp program. Click or tap on the image to enlarge it.

The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 4 a.m. for the morning chart. These are the chart times. Note that Interlochen/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 4 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.

July Morning Star Chart

Star Chart for July mornings, 2023 (4 am EDT, July 15, 2023). Created using my LookingUp program. Click or tap on the image to enlarge it.

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.
  • The Summer Triangle is in red.
  • DAqR is the radiant of the South Delta Aquariid meteor shower (Peaks on the morning of the 28th)

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning Twilight Evening Twilight Dark Night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2023-07-01 3h38m 4h41m 23h00m 0h03m – – 0.98
2023-07-02 3h39m 4h42m 23h00m 0h02m – – 1.00
2023-07-03 3h40m 4h43m 22h59m 0h01m – – 0.99
2023-07-04 3h42m 4h43m 22h59m 0h00m – – 0.96
2023-07-05 3h43m 4h44m 22h58m 0h00m – – 0.89
2023-07-06 3h44m 4h45m 22h58m 23h59m 23h59m – 0.81
2023-07-07 3h46m 4h46m 22h57m 23h57m 23h57m 0h16m 0.71
2023-07-08 3h47m 4h47m 22h56m 23h56m 23h56m 0h39m 0.60
2023-07-09 3h49m 4h48m 22h56m 23h55m 23h55m 0h59m 0.49
2023-07-10 3h50m 4h49m 22h55m 23h54m 23h54m 1h19m 0.38
2023-07-11 3h52m 4h50m 22h54m 23h53m 23h53m 1h40m 0.28
2023-07-12 3h53m 4h52m 22h53m 23h51m 23h51m 2h03m 0.19
2023-07-13 3h55m 4h53m 22h52m 23h50m 23h50m 2h30m 0.12
2023-07-14 3h57m 4h54m 22h51m 23h48m 23h48m 3h04m 0.06
2023-07-15 3h58m 4h55m 22h50m 23h47m 23h47m 3h46m 0.02
2023-07-16 4h00m 4h56m 22h49m 23h45m 23h45m 4h00m 0.00
2023-07-17 4h02m 4h58m 22h48m 23h44m 23h44m 4h02m 0.00
2023-07-18 4h04m 4h59m 22h47m 23h42m 23h42m 4h04m 0.02
2023-07-19 4h05m 5h00m 22h46m 23h40m 23h40m 4h05m 0.05
2023-07-20 4h07m 5h02m 22h44m 23h39m 23h39m 4h07m 0.10
2023-07-21 4h09m 5h03m 22h43m 23h37m 23h37m 4h09m 0.17
2023-07-22 4h11m 5h04m 22h42m 23h35m 23h51m 4h11m 0.25
2023-07-23 4h13m 5h06m 22h41m 23h33m – 4h13m 0.33
2023-07-24 4h15m 5h07m 22h39m 23h31m 0h07m 4h15m 0.43
2023-07-25 4h17m 5h08m 22h38m 23h30m 0h25m 4h17m 0.53
2023-07-26 4h19m 5h10m 22h36m 23h28m 0h44m 4h19m 0.63
2023-07-27 4h21m 5h11m 22h35m 23h26m 1h08m 4h21m 0.73
2023-07-28 4h23m 5h13m 22h33m 23h24m 1h39m 4h23m 0.83
2023-07-29 4h24m 5h14m 22h32m 23h22m 2h19m 4h24m 0.90
2023-07-30 4h26m 5h16m 22h30m 23h20m 3h14m 4h26m 0.96
2023-07-31 4h28m 5h17m 22h29m 23h18m 4h24m 4h28m 0.99

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

Jul  1  Sa            Venus: 41.7° E
     1  Sa  12:46 am  Mercury Superior Conj.
     1  Sa   2:48 am  Venus-Mars: 3.6° N Quasi-conjunction
     1  Sa   3:20 am  Moon-Antares: 1.5° S
     2  Su   9:23 pm  Moon South Dec.: 27.8° S
     3  Mo   7:39 am  Full Buck Moon
     4  Tu   6:28 pm  Moon Perigee: 360,200 km
     6  Th   4:59 am  Aphelion: 1.0167 AU
     6  Th  11:05 pm  Moon-Saturn: 2.7° N
     7  Fr            Venus greatest brilliancy, magnitude -4.7
     9  Su   9:48 pm  Last Quarter
    10  Mo   1:18 am  Mars-Regulus:  0.6° N
    10  Mo   9:23 pm  Moon Ascending Node
    11  Tu   5:18 pm  Moon-Jupiter: 2.3° S
    13  Th   2:31 am  Moon-Pleiades: 1.8° N
    14  Fr   6:33 pm  Mercury-Beehive:  0.2° N
    15  Sa  10:40 pm  Moon North Dec.: 27.8° N
    16  Su   3:49 am  Venus-Regulus: 3.3° S
    17  Mo   2:32 pm  New Moon
    20  Th   2:56 am  Moon Apogee: 406,300 km
    20  Th  12:00 am  Moon-Mars: 3.6° S
    25  Tu  11:05 am  Moon Descending Node
    25  Tu   6:07 pm  First Quarter
    27  Th   7:00 am  Mercury-Venus: 5.1° N
    28  Fr  11:35 am  Delta Aquariid Shower: ZHR = 20
    28  Fr   1:11 pm  Moon-Antares: 1.3° S
    28  Fr   2:21 pm  Mercury-Regulus:  0.1° S
    30  Su   7:13 am  Moon South Dec.: 27.9° S
Aug  1  Tu            Venus: 18.7° E

All event times are given for UTC-5:00: Eastern Standard Time before the 14th or UTC-4:00 Daylight Saving Time thereafter.

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.

Note that the site is now kept up for archival purposes. Fred Espenak retired from NASA several years ago and has his own site, AstroPixels, which contain the same information: http://astropixels.com/almanac/almanac.html. However it uses standard time all year.

NASA Calendar of Planetary Events

     LU                  Ephemeris of Sky Events for Interlochen/TC
June, 2023    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Thu  1| 06:00a  09:21p  15:20 | 10:44p  04:37a |      Set  04:43a   94%|
|Fri  2| 05:59a  09:22p  15:22 | 10:45p  04:36a |      Set  05:14a   98%|
|Sat  3| 05:59a  09:22p  15:23 | 10:46p  04:35a |Full  Rise 09:27p  100%|
+------+-----------------------+----------------+-----------------------+
|Sun  4| 05:59a  09:23p  15:24 | 10:47p  04:35a |      Rise 10:42p   99%|
|Mon  5| 05:58a  09:24p  15:25 | 10:48p  04:34a |      Rise 11:47p   95%|
|Tue  6| 05:58a  09:25p  15:26 | 10:49p  04:33a |      Rise 12:39a   89%|
|Wed  7| 05:57a  09:25p  15:27 | 10:50p  04:33a |      Rise 01:18a   80%|
|Thu  8| 05:57a  09:26p  15:28 | 10:51p  04:32a |      Rise 01:48a   70%|
|Fri  9| 05:57a  09:27p  15:29 | 10:52p  04:32a |      Rise 02:13a   59%|
|Sat 10| 05:57a  09:27p  15:30 | 10:53p  04:31a |L Qtr Rise 02:34a   48%|
+------+-----------------------+----------------+-----------------------+
|Sun 11| 05:56a  09:28p  15:31 | 10:53p  04:31a |      Rise 02:53a   37%|
|Mon 12| 05:56a  09:28p  15:31 | 10:54p  04:31a |      Rise 03:13a   27%|
|Tue 13| 05:56a  09:29p  15:32 | 10:55p  04:30a |      Rise 03:34a   18%|
|Wed 14| 05:56a  09:29p  15:33 | 10:55p  04:30a |      Rise 03:59a   10%|
|Thu 15| 05:56a  09:30p  15:33 | 10:56p  04:30a |      Rise 04:28a    5%|
|Fri 16| 05:56a  09:30p  15:33 | 10:56p  04:30a |      Rise 05:04a    2%|
|Sat 17| 05:56a  09:30p  15:34 | 10:57p  04:30a |      Rise 05:49a    0%|
+------+-----------------------+----------------+-----------------------+
|Sun 18| 05:56a  09:31p  15:34 | 10:57p  04:30a |New   Set  10:36p    1%|
|Mon 19| 05:56a  09:31p  15:34 | 10:57p  04:30a |      Set  11:22p    3%|
|Tue 20| 05:56a  09:31p  15:34 | 10:58p  04:30a |      Set  11:58p    8%|
|Wed 21| 05:57a  09:32p  15:34 | 10:58p  04:30a |      Set  12:27a   13%|
|Thu 22| 05:57a  09:32p  15:34 | 10:58p  04:31a |      Set  12:51a   20%|
|Fri 23| 05:57a  09:32p  15:34 | 10:58p  04:31a |      Set  01:11a   28%|
|Sat 24| 05:57a  09:32p  15:34 | 10:58p  04:31a |      Set  01:29a   37%|
+------+-----------------------+----------------+-----------------------+
|Sun 25| 05:58a  09:32p  15:34 | 10:58p  04:32a |      Set  01:45a   47%|
|Mon 26| 05:58a  09:32p  15:33 | 10:58p  04:32a |F Qtr Set  02:02a   57%|
|Tue 27| 05:59a  09:32p  15:33 | 10:58p  04:33a |      Set  02:21a   66%|
|Wed 28| 05:59a  09:32p  15:32 | 10:58p  04:33a |      Set  02:43a   76%|
|Thu 29| 05:59a  09:32p  15:32 | 10:58p  04:34a |      Set  03:10a   84%|
|Fri 30| 06:00a  09:32p  15:31 | 10:57p  04:34a |      Set  03:45a   92%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunrise and sunset 

Created using my LookingUp for DOS output as text.

Categories: Ephemeris Program, Month preview, Observing Tags: