03/03/2022 – Ephemeris – Finding Cancer the crab
This is Ephemeris for Thursday, March 3rd. Today the Sun will be up for 11 hours and 16 minutes, setting at 6:33, and it will rise tomorrow at 7:15. The Moon, 1 day past new, will set at 7:46 this evening.
The constellation of Cancer the crab is made of dim stars, which are generally connected, in constellation charts, with lines that make either the letter K or an upside down Y, which lie directly between the star pair Castor and Pollux in Gemini and Regulus in Leo. In the center of the constellation is, what to the naked-eye is a fuzzy spot called Praesepe, or the manger. The two nearby stars, one to the northeast, and one to the southeast are Asellus Borealis, and Asellus Australis, the northern and southern donkey colts feeding out of the manger. Viewing that fuzzy spot with a pair of binoculars will reveal that it’s not fuzzy at all. It resolves into a cluster of stars, which astronomers, over the years, have called the Beehive cluster. Back in the first and second century CE, the Sun entered Cancer to begin the season of summer. It’s now just a transitional constellation between the winter and spring evening skies.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
Cancer, the crab finder chart. Note the beehive cluster, also known to amateur astronomers as M44, along with other catalog names. Prior to the invention of the telescope this cluster was known as Praesepe which means “Manger”. Click on the image to enlarge it. Created using Stellarium and GIMP.
A closer look at Cancer, noting the donkey stars Asellus Borealis and Australis feeding at the manger, Praesepe or M44, aka: the Beehive Cluster. Created using Cartes du Ciel (Sky Charts) and LibreOffice for captions. Adapted from a chart I created for the March 2022 issue of the GTAS newsletter, the Stellar Sentinel.
03/02/2023 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Ash Wednesday, March 2nd. Today the Sun will be up for 11 hours and 13 minutes, setting at 6:31, and it will rise tomorrow at 7:16. The Moon is new today, and won’t be visible.
Let’s search for the naked-eye planets for this week. The last evening planet, Jupiter, will pass behind the Sun this Saturday and enter the morning sky. So the action shifts to the morning sky, where Saturn, Mercury, Venus and Mars reside. Saturn and Mercury are too close to the direction of the Sun to be spotted now. Mercury is heading back toward the Sun. Saturn should be able to be spotted in morning twilight in a few weeks as it joins Venus, our brilliant morning star, and Mars in the southeast about half an hour to 45 minutes before sunrise. Tomorrow morning Mars will be below, and right of bright Venus, which will rise at 5 am, with Mars following at 5:26.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
Venus and Mars in the morning as they might appear at 6:30 am, about 45 minutes before sunrise, Thursday, March 3, 2022. Created using Stellarium.
Venus through a telescope as it would appear before sunrise tomorrow morning, March 3, 2022. It’s shown larger than usual, since it’s the only planet that looks like anything in a small telescope now. Its apparent diameter is 30.49″, and it is 39.7% illuminated by the Sun. Mars has an apparent diameter of 4.73″.
(” means seconds of arc. 1″ is 1/3600th of a degree). Created using Stellarium, which is also the source for the apparent diameters and the illuminated fraction of Venus.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on March 2, 2022. The night ends on the left with sunrise on the 3rd. There’s a label pile up in the sunrise panel where the Labels for Saturn and Mercury overlay each other. Click on the image to enlarge it. Created using my LookingUp program.
03/01/2022 – Ephemeris – Previewing March skies
This is Ephemeris for Fat Tuesday, March 1st. Today the Sun will be up for 11 hours and 10 minutes, setting at 6:30, and it will rise tomorrow at 7:18. The Moon, 1 day before new, will rise at 7:44 tomorrow morning.
Let’s look at the skies for the month of March. The Sun will cross the celestial equator in March as the promising season of spring will begin. Daylight hours in the Interlochen/Traverse City area and will increase from 11 hours and 10 minutes today to 12 hours 43 minutes on the 31st. The altitude, or angle, of the Sun above the southern horizon at local noon will be just under 38 degrees today and will ascend to nearly 50 degrees on the 31st. The altitude of the Sun in the Straits area will be a degree lower. Local apparent noon this month, when the Sun passes due south, will be about 12:51 p.m. and an hour later when Daylight Saving Time starts on the 13th. Spring will begin on the 20th at 11:33 am.
Addendum
March Evening Star Chart
Star Chart for March 2022 (10 pm EDT, March 15, 2022). Click on the image to enlarge it. 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. Note that Traverse City is located approximately 45 minutes behind our time meridian. (An hour and 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 1 hour 45 minutes earlier than your current time.
Note the chart times of 10 p.m. and 6 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. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog.
March Morning Star Chart
Star Chart for March mornings, 2022 (6 a.m. EDT March 15, 2022). Click on image to enlarge. Created using my LookingUp program.
Only Venus of all the morning planets has yet to rise at chart time on the 15th.
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, and
- Extend it as a spike to Spica.
- 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. |
| 2022-03-01 | 5h44m | 6h18m | 19h32m | 20h06m | 20h06m | 5h44m | 0 |
| 2022-03-02 | 5h42m | 6h16m | 19h33m | 20h07m | 20h07m | 5h42m | 0 |
| 2022-03-03 | 5h40m | 6h14m | 19h35m | 20h09m | 20h09m | 5h40m | 0.03 |
| 2022-03-04 | 5h39m | 6h13m | 19h36m | 20h10m | 20h57m | 5h39m | 0.07 |
| 2022-03-05 | 5h37m | 6h11m | 19h37m | 20h11m | 22h06m | 5h37m | 0.13 |
| 2022-03-06 | 5h35m | 6h09m | 19h39m | 20h13m | 23h13m | 5h35m | 0.21 |
| 2022-03-07 | 5h33m | 6h07m | 19h40m | 20h14m | – | 5h33m | 0.29 |
| 2022-03-08 | 5h31m | 6h05m | 19h41m | 20h15m | 0h20m | 5h31m | 0.38 |
| 2022-03-09 | 5h30m | 6h04m | 19h43m | 20h17m | 1h25m | 5h30m | 0.48 |
| 2022-03-10 | 5h28m | 6h02m | 19h44m | 20h18m | 2h28m | 5h28m | 0.57 |
| 2022-03-11 | 5h26m | 6h00m | 19h45m | 20h19m | 3h26m | 5h26m | 0.66 |
| 2022-03-12 | 5h24m | 5h58m | 19h46m | 20h21m | 4h18m | 5h24m | 0.75 |
| 2022-03-13 | 6h22m | 6h56m | 20h48m | 21h22m | 6h03m | 6h22m | 0.83 |
| 2022-03-14 | 6h20m | 6h54m | 20h49m | 21h24m | – | – | 0.9 |
| 2022-03-15 | 6h18m | 6h53m | 20h50m | 21h25m | – | – | 0.95 |
| 2022-03-16 | 6h16m | 6h51m | 20h52m | 21h26m | – | – | 0.99 |
| 2022-03-17 | 6h14m | 6h49m | 20h53m | 21h28m | – | – | 1 |
| 2022-03-18 | 6h12m | 6h47m | 20h54m | 21h29m | – | – | 0.99 |
| 2022-03-19 | 6h10m | 6h45m | 20h56m | 21h31m | 21h31m | 21h42m | 0.96 |
| 2022-03-20 | 6h12m | 6h47m | 21h01m | 21h36m | 21h36m | 22h58m | 0.9 |
| 2022-03-21 | 6h10m | 6h45m | 21h02m | 21h37m | 21h37m | – | 0.82 |
| 2022-03-22 | 6h08m | 6h43m | 21h04m | 21h39m | 21h39m | 0h15m | 0.73 |
| 2022-03-23 | 6h06m | 6h41m | 21h05m | 21h40m | 21h40m | 1h34m | 0.62 |
| 2022-03-24 | 6h04m | 6h39m | 21h06m | 21h42m | 21h42m | 2h50m | 0.5 |
| 2022-03-25 | 6h02m | 6h37m | 21h08m | 21h43m | 21h43m | 3h59m | 0.39 |
| 2022-03-26 | 6h00m | 6h35m | 21h09m | 21h45m | 21h45m | 4h57m | 0.28 |
| 2022-03-27 | 5h58m | 6h33m | 21h10m | 21h46m | 21h46m | 5h43m | 0.19 |
| 2022-03-28 | 5h55m | 6h31m | 21h12m | 21h48m | 21h48m | 5h55m | 0.11 |
| 2022-03-29 | 5h53m | 6h29m | 21h13m | 21h49m | 21h49m | 5h53m | 0.05 |
| 2022-03-30 | 5h51m | 6h27m | 21h15m | 21h51m | 21h51m | 5h51m | 0.01 |
| 2022-03-31 | 5h49m | 6h25m | 21h16m | 21h52m | 21h52m | 5h49m | 0 |
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/2019/09/27/
NASA Calendar of Planetary Events
Date Time Event
Mar 1 Tu Venus: 45° W
2 We 10:48 am Mercury-Saturn: 0.7° N
2 We 12:35 pm New Moon
5 Sa 7:51 am Jupiter Solar Conjunction
8 Tu 3:22 am Moon Ascending Node
10 Th 5:45 am First Quarter
10 Th 6:05 pm Moon Apogee: 404,300 km
11 Fr 7:14 pm Moon Northernmost Declination: 26.7° N
13 Su 1:58 am Moon-Pollux: 2.6° N
13 Su 6:08 am Neptune Solar Conjunction
14 Mo 3:55 am Moon-Beehive: 3.7° S
15 Tu 11:12 pm Venus-Mars: 3.9° N
18 Fr 3:17 am Full Worm Moon
20 Su 5:59 am Venus Elongation: 46.6° West
20 Su 11:33 am Vernal Equinox
22 Tu 4:12 am Moon Descending Node
23 We 7:28 pm Moon Perigee: 369,800 km
25 Fr 1:37 am Last Quarter
25 Fr 7:58 am Moon Southernmost Declination: 26.8° S
27 Su 10:54 pm Moon-Mars: 4.2° N
28 Mo 5:50 am Moon-Venus: 6.9° N
28 Mo 7:43 am Moon-Saturn: 4.5° N
28 Mo 8:53 pm Venus-Saturn: 2.1° N
Apr 1 Fr Venus: 46.1° W
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.
Sun and Moon Rising and Setting Events
LU Ephemeris of Sky Events for Interlochen/TC March, 2022 Local time zone: EST +-----------------------------------------------------------------------+ | DATE | SUN SUN DAYLIGHT| TWILIGHT* |MOON RISE OR ILLUM | | | RISE SET HOURS | END START |PHASE SET** TIME FRACTN| +=======================================================================+ |Tue 1| 07:20a 06:30p 11:10 | 07:33p 06:17a | Rise 07:44a 1%| |Wed 2| 07:18a 06:31p 11:13 | 07:35p 06:15a |New Set 06:32p 0%| |Thu 3| 07:16a 06:33p 11:16 | 07:36p 06:13a | Set 07:46p 2%| |Fri 4| 07:15a 06:34p 11:19 | 07:37p 06:12a | Set 08:56p 6%| |Sat 5| 07:13a 06:35p 11:22 | 07:39p 06:10a | Set 10:05p 12%| +------+-----------------------+----------------+-----------------------+ |Sun 6| 07:11a 06:37p 11:25 | 07:40p 06:08a | Set 11:13p 19%| |Mon 7| 07:09a 06:38p 11:28 | 07:41p 06:06a | Set 12:19a 27%| |Tue 8| 07:07a 06:39p 11:32 | 07:42p 06:04a | Set 01:25a 36%| |Wed 9| 07:06a 06:41p 11:35 | 07:44p 06:03a | Set 02:28a 46%| |Thu 10| 07:04a 06:42p 11:38 | 07:45p 06:01a |F Qtr Set 03:26a 55%| |Fri 11| 07:02a 06:43p 11:41 | 07:46p 05:59a | Set 04:18a 64%| |Sat 12| 07:00a 06:45p 11:44 | 07:48p 05:57a | Set 05:02a 73%| +------+-----------------------+----------------+-----------------------+ | EDT | Time Change | | | |Sun 13| 07:58a 07:46p 11:47 | 08:49p 06:55a | Set 06:39a 81%| |Mon 14| 07:56a 07:47p 11:50 | 08:50p 06:53a | Set 07:10a 88%| |Tue 15| 07:55a 07:49p 11:53 | 08:52p 06:52a | Set 07:36a 94%| |Wed 16| 07:53a 07:50p 11:57 | 08:53p 06:50a | Set 07:59a 98%| |Thu 17| 07:51a 07:51p 12:00 | 08:54p 06:48a | Set 08:20a 100%| |Fri 18| 07:49a 07:52p 12:03 | 08:56p 06:46a |Full Rise 08:28p 99%| |Sat 19| 07:47a 07:54p 12:06 | 08:57p 06:44a | Rise 09:42p 96%| +------+-----------------------+----------------+-----------------------+ |Sun 20| 07:45a 07:55p 12:09 | 08:58p 06:42a | Rise 10:57p 91%| |Mon 21| 07:43a 07:56p 12:12 | 09:00p 06:40a | Rise 12:15a 84%| |Tue 22| 07:42a 07:57p 12:15 | 09:01p 06:38a | Rise 01:34a 75%| |Wed 23| 07:40a 07:59p 12:18 | 09:02p 06:36a | Rise 02:50a 64%| |Thu 24| 07:38a 08:00p 12:22 | 09:04p 06:34a | Rise 03:59a 53%| |Fri 25| 07:36a 08:01p 12:25 | 09:05p 06:32a |L Qtr Rise 04:56a 41%| |Sat 26| 07:34a 08:02p 12:28 | 09:06p 06:30a | Rise 05:42a 30%| +------+-----------------------+----------------+-----------------------+ |Sun 27| 07:32a 08:04p 12:31 | 09:08p 06:28a | Rise 06:18a 21%| |Mon 28| 07:30a 08:05p 12:34 | 09:09p 06:26a | Rise 06:47a 12%| |Tue 29| 07:29a 08:06p 12:37 | 09:11p 06:24a | Rise 07:10a 6%| |Wed 30| 07:27a 08:07p 12:40 | 09:12p 06:22a | Rise 07:31a 2%| |Thu 31| 07:25a 08:09p 12:43 | 09:13p 06:20a | Rise 07:51a 0%| +-----------------------------------------------------------------------+ * Nautical Twilight ** Moonrise or moonset, whichever occurs between sunrise and sunset
Created using my LookingUp for DOS output as text.
02/28/2022 – Ephemeris – Ancient Egypt’s most important star
This is Ephemeris for Monday, February 28th. Today the Sun will be up for 11 hours and 7 minutes, setting at 6:29, and it will rise tomorrow at 7:20. The Moon, 2 days before new, will rise at 7:17 tomorrow morning.
The Ancient Egyptian agricultural year began with the flooding of the Nile, which was announced by the heliacal rising of the brightest nighttime star, Sirius. A heliacal rising is the first appearance of a star in the morning twilight after disappearing in evening twilight some months before. The Greeks called the star Sothis, while the ancient Egyptians called the star Sopdet. The heliacal rising would occur on July 20th had our calendar been in use back then. The relationship between the summer solstice and the heliacal rising of Sothis, 29 days later, stayed the same for nearly three millennia, from at least 2900 BCE to 12 CE, despite precession* of the Earth’s axis moving the Sun from the middle of the constellation Leo at the summer solstice to the western edge of Cancer one and a half constellations west. Sopdet was personified by a goddess, who was the consort to Sah, who is what they called Orion.
———-
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
* Precession of the equinoxes. The slow, 26,000 year wobble of the Earth’s axis which causes the Earth, most of the time, to not have a pole star. We’re lucky to live at a time to have a bright star within a degree of the north celestial pole. That star is, of course, Polaris. Precession also changes the point in the sky, along the ecliptic and zodiac, where the Sun appears on the first day of spring, or any season. These points move westward along the ecliptic (the plane of the earth’s orbit of the Sun) one degree every 72 years.
Addendum
The Egyptian used the heliacal rising of Sirius as a signal that the flooding of the Nile was imminent, starting their agricultural year. The Greeks called the star Sothis, while the Egyptians themselves called it Sopdet, a goddess, and consort of the god Sah, our Orion.
Part of my presentation, December 2021 of Ancient Astronomy of the Egyptians and Babylonians.
02/25/2022 – Ephemeris – The star that’s called the Pup
This is Ephemeris for Friday, February 25th. Today the Sun will be up for 10 hours and 58 minutes, setting at 6:25, and it will rise tomorrow at 7:25. The Moon, 2 days past last quarter, will rise at 5:04 tomorrow morning.
Sirius is the brightest nighttime star and is located in the south at 9 p.m. below and a bit left of Orion the Hunter. We’ve visited Sirius last Friday. But there is another star in the Sirius system that is practically invisible due to Sirius’ dazzling glare. Its name is Sirius B, nicknamed the Pup, alluding to Sirius’ Dog Star title as the heart of Canis Major, Orion’s larger hunting dog. The tiny star was suspected as far back as 1834 due to Sirius’ wavy path in the sky against the more distant stars. Sirius and the Pup have 50-year orbits of each other. The Pup was first seen by famed 19th century telescope maker Alvan Clark in 1862 while testing a new telescope. The Pup was the first of a new class of stars to be discovered, white dwarfs. The Pup, with the mass of the Sun, is packed into the volume of the Earth.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
A Sirius finder animation for late January/early February at around 8 pm. Even in bright moonlight, the seven bright stars of Orion can be seen. The three stars of Orion’s belt make a great pointer to Sirius. Created using Stellarium, GIMP and Libreoffice (for the arrow).
Sirius A & B’s path in the sky, showing the wobble that betrayed the Pup’s presence. Credit Mike Guidry, University of Tennessee.
Sirius A and B imaged by two different space telescopes, revealing dramatically different views! Hubble’s image (left) shows Sirius A shining brightly in visible light, with diminutive Sirius B a tiny dot. However, in Chandra’s image (right) tiny Sirius B is dramatically brighter in X-rays! The “Universe in a Different Light” activity highlights more surprising views of some familiar objects: http://bit.ly/different-light-nsn NASA, ESA, H. Bond (STScI), and M. Barstow (University of Leicester) (left); NASA/SAO/CXC (right)
02/24/2022 – Ephemeris – The celestial unicorn
This is Ephemeris for Thursday, February 24th. Today the Sun will be up for 10 hours and 55 minutes, setting at 6:23, and it will rise tomorrow at 7:27. The Moon, 1 day past last quarter, will rise at 3:57 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 south-southeastern sky at 8 p.m. mostly bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left and above. Unfortunately for observers without a telescope, Monoceros, 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 telescopic observer and astrophotographer it is a feast of faint nebulae or clouds of gas and dust, the birthplace of stars, including the red rose of the Rosette Nebula* (NGC 2237), and Hagrid’s Dragon Cluster (NGC 2301), which sounds suspiciously like it was recently, and unofficially, named. Monoceros also contains a beautiful telescopic triple star system, Beta (β) Monocerotis.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
* The Rosette nebula surrounds the star cluster NGC 2244. This sparse star cluster is visible visually in telescopes. I’ve never been able to spot the nebula in a telescope, but it shows up, faintly, in my wide angle photographs of the area.
Addendum
Deep Sky Objects in and around Monoceros. Deep Sky Objects are telescopic objects that lie beyond the solar system. Click on the image to enlarge. Created using Stellarium.
Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech
The brighter stars of NGC 2301 (Hagrid’s Dragon Cluster, AKA Great Bird Cluster and Copeland’s Golden Worm). It’s also in two other catalogs: Cr 119 and Mel 54. Created using Stellarium and GIMP. The dragon image is from “Dragon Flying Cycle” on YouTube by Simon Hussey.
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.
02/23/2022 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Wednesday, February 23rd. Today the Sun will be up for 10 hours and 52 minutes, setting at 6:22, and it will rise tomorrow at 7:28. The Moon, at last quarter today, will rise at 2:43 tomorrow morning.
Let’s search for the naked-eye planets for this week. The last evening planet, Jupiter, is too close to the setting Sun to be spotted now after sunset. The action now shifts to the morning sky, where Venus and Mars reside. Saturn entered the morning sky sixteen days ago, and it will be about another month or so before it’s far enough from the direction of the Sun to be spotted. Venus, our brilliant morning star, Mars and maybe even Mercury can be spotted low in the southeast by 6:45 am, about half an hour before sunrise. Mars will be below, and right of Venus, while Mercury will be near the horizon left of Venus. Mercury is brighter than Mars, but lower in the more intense twilight. Venus will rise at 5:06, with Mars following at 5:38, and Mercury rising last at 6:32.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
Morning planets and the waning crescent Moon at 6:45 am, or about 40 minutes before sunrise tomorrow morning, February 24, 2022. Mercury may not actually be visible. Click on the image to enlarge it. Created using Stellarium.
Waning Crescent Moon as it might be shown in binoculars or small telescope tomorrow morning, February 24, 2022. Created using Stellarium.
Venus through a telescope as it would appear before sunrise tomorrow morning, February 24, 2022. It’s shown larger than usual, since it’s the only planet that looks like anything in a small telescope now. Its apparent diameter is 33.72″, and it is 34.9% illuminated by the Sun.
(” means seconds of arc. 1″ is 1/3600th of a degree) Mars has an apparent diameter of 4.63″, while Mercury has one of 6.18″. Created using Stellarium, which is also the source for the apparent diameters and the illuminated fraction of Venus.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on February 23, 2022. The night ends on the left with sunrise on the 24th. Click on the image to enlarge it. Created using my LookingUp program.
02/22/2022 – Ephemeris – The Winter Triangle
This is Ephemeris for Tuesday, February 22nd. Today the Sun will be up for 10 hours and 49 minutes, setting at 6:21, and it will rise tomorrow at 7:30. The Moon, 1 day before last quarter, will rise at 1:26 tomorrow morning.
I’ve talked about the Winter Circle of bright stars already this winter, 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 almost invisible constellation of Monoceros the unicorn. The Summer Triangle has three bright stars with no other close competition. The Winter Triangle has four other bright stars near it. Any three of these would make a nice triangle. One of these constellations, Canis Minor, is tiny with Procyon and one other star. It makes me think of a dachshund, or maybe, if I’m hungry, a hot dog.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT -5 hours). They may be different for your location.
Addendum
The Winter Triangle. It encloses a pretty blank space where Monoceros the unicorn lies. Created using Stellarium with my annotations for the Winter Triangle.
02/21/2022 – Ephemeris – The time President Abraham Lincoln visited the US Naval Observatory
This is Ephemeris for President’s Day, Monday, February 21st. Today the Sun will be up for 10 hours and 46 minutes, setting at 6:19, and it will rise tomorrow at 7:32. The Moon, 2 days before last quarter, will rise at 12:09 tomorrow morning.
In August 1863, during the height of the Civil War, President Abraham Lincoln and his secretary John Hay rode out to the Naval Observatory, where it was back then in Foggy Bottom. The astronomer there, Asaph Hall, showed them the Moon and the star Arcturus through the observatory’s telescope. A couple of nights later Lincoln came out alone to ask the astronomer some questions about what he saw, in including why the Moon was upside down in the observatory telescope while the telescope he used gave a right side up image.* Fourteen years later, Asaph Hall, still at the Naval Observatory, discovered the two satellites of Mars through the observatory’s then larger telescope.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
The 9.6 inch telescope through which Lincoln viewed the Moon and Arcturus on the night of August 22, 1863. From the Astronomy.com website.
The old Naval Observatory. From the Astronomy.com website.
* Most telescopes naturally create an upside down image. The spyglass type telescope President Lincoln was probably familiar with was a Galilean telescope that didn’t form an image within it. Telescopes like binoculars use prisms to erect the image. Astronomers don’t care if the image is upside down. Whatever is used to turn the image right side up reduces the amount of light that makes it through the telescope. For astronomers, the name of the game is to capture more light and increase the ability to see fine detail, which are both functions of the primary’s diameter. That’s why modern telescopes are measured by the diameter of their primary mirrors or lenses.
02/18/2022 – Ephemeris – Sirius, the brightest nighttime star
This is Ephemeris for Friday, February 18th. Today the Sun will be up for 10 hours and 37 minutes, setting at 6:15, and it will rise tomorrow at 7:36. The Moon, 2 days past full, will rise at 8:32 this evening.
In the evening, the great constellation of Orion the hunter can be seen in the south. Its large rectangle of bright stars is easily visible, even with a full moon. The three stars in a straight line, his belt, tilt downward to the left to a very bright star merrily twinkling lower in the sky. This star is called Sirius, also known as the Dog Star because it’s in the heart of Orion’s larger hunting dog, Canis Major. It is an arc light white star as seen in binoculars or telescope. It is the brightest star in the night sky, and a neighboring star, just twice the distance of the closest star to the Sun at 8.6 light years. It’s name, Sirius, has nothing to do with a dog, but is from the Greek meaning scorching for its brightness or sparkling, due to its intense twinkling.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
In the southern sky, Orion’s belt points to Sirius. Created using Stellarium, Libreoffice and GIMP.
