Archive
03/29/2019 – Ephemeris – The Stars Mizar and Alcor in the Big Dipper
Ephemeris for Friday, March 29th. Today the Sun will be up for 12 hours and 36 minutes, setting at 8:06, and it will rise tomorrow at 7:27. The Moon, 1 day past last quarter, will rise at 5:03 tomorrow morning.
The most interesting star in the Big Dipper is Mizar and its dim companion Alcor. It is the second star from the end of the handle, where the bend in the handle takes place. Folks with good vision can see the dimmer star right next to Mizar. In ancient times it was used as an eye test for visual acuity for warriors. As such it was known as the “Horse and the Rider”. Mizar is second magnitude, in the second rank of star brightness invented by the Greek astronomer Hipparchus in the 2nd century BC. He ranked stars in 6 classes, from first magnitude for the brightest to 6th for the dimmest visible to the naked eye. Alcor comes in at 4th magnitude. It does suffer a bit by being very close to Mizar which is 6 times brighter.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
03/28/2019 – Ephemeris – The Big Dipper as seen by some other countries
Ephemeris for Thursday, March 28th. Today the Sun will be up for 12 hours and 33 minutes, setting at 8:05, and it will rise tomorrow at 7:29. The Moon, at last quarter today, will rise at 4:21 tomorrow morning.
The Big Dipper is climbing up the northeastern sky at 9:30 in the evening, it’s seven stars shining brightly. The Big Dipper is not an actual constellation, recognized internationally. It’s part, the hind part, of Ursa Major, the great bear. The Big Dipper is an asterism or informal constellation. It is a distinctly North American constellation. For fugitive slaves, fleeing the southern states in the days before the Civil War, the Drinking Gourd, as they called it, showed the direction north to freedom. In England the dipper stars become the Plough, or Charles’ Wain (Charlemagne’s Wagon). In France, known for culinary delights it was the saucepan, or the cleaver. Many cultures saw what was familiar to them in these seven bright stars.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Cultural views of the Big Dipper as an Animation: Big Dipper/Sauce Pan, Plough (plow), Charle’s Wain (Charlemagne’s wagon), Cleaver.
03/27/2019 – Ephemeris – Looking for and at the bright planets for this week
Ephemeris for Wednesday, March 27th. Today the Sun will be up for 12 hours and 30 minutes, setting at 8:03, and it will rise tomorrow at 7:31. The Moon, 1 day before last quarter, will rise at 3:33 tomorrow morning.
Let’s look at the planets for this week. Mars will be in the western sky this evening, below the Pleiades, or Seven Sisters, star cluster. It will pass to the left of the Pleiades Saturday night. Tonight, however, it will set at 12:34 a.m. In the morning sky we have Jupiter which will rise tomorrow at 2:29 a.m. in the east-southeast. It is second to Venus in brightness. Saturn will be next to rise at 4:14 a.m., also in the east-southeast. Venus will rise at 6:20 a.m. also in the east-southeast. By 7 in the morning they will be strung out from the southeast to the south, with the last quarter Moon between Jupiter and Saturn. The Moon will pass Saturn early Friday morning before it rises and will be seen then to the left of Saturn.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars tiptoeing past the Pleiades nightly from March 26th to April 1st, 2019. Looking west. Created using Stellarium and GIMP.
Morning planets and the Moons at 6:45 a.m. tomorrow March 28, 2019. Click on the image to enlarge. Created using Stellarium.
The moon as it might appear in binoculars tomorrow morning, March 28, 2019. Created using Stellarium.
Jupiter, Saturn and Venus with the same magnification at 6:45 a.m. tomorrow morning March 28, 2019. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 27, 2019. The night ends on the left with sunrise on the 28th. Click on the image to enlarge. Created using my LookingUp program.
03/26/2019 – Ephemeris – Mars is approaching the Pleiades this week
Ephemeris for Tuesday, March 26th. Today the Sun will be up for 12 hours and 27 minutes, setting at 8:02, and it will rise tomorrow at 7:33. The Moon, 2 days before last quarter, will rise at 2:38 tomorrow morning.
Daylight time and spring time are catching up with us with the Sun setting now just after 8 p.m. By 9 p.m. tonight the brighter stars appear and most of the well known constellations will be recognizable. Looking off to the west at that time the famous star group of the Pleiades, or Seven Sisters will appear. Folks with good eyesight can see six or maybe even seven of its stars. Tonight, right below the Pleiades is a bright reddish star. It would be the 22nd of the first magnitude stars, except it’s not a star. It’s a wanderer, according to the ancient Greeks, one of seven*. They called it Ares the god of war. The Romans turned it into Mars. Over the week Mars will be closing in and passing by the Pleiades this weekend.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The western sky at 10:22 last night March 25, 2019. Mars appears below the Pleiades in zodiacal light. Credit, mine – Canon EOS Rebel T5 18mm f.l., f/3.5, 8 sec. ISO 12,800.
Mars tiptoeing past the Pleiades nightly from March 26th to April 1st, 2019 at 9 p.m. Looking west. Created using Stellarium and GIMP.
The letter V of stars to the left of the Pleiades is the Hyades, in mythology the half sisters to the Pleiades. It is also the face of Taurus the bull.
* We get the word planet from the Greek planētes meaning wander. Five are the classical planets, Mercury, Venus, Mars, Jupiter, and Saturn. The other two are the Sun and Moon. The other celestial objects were the fixed stars. Other things that appear in the sky, like comets, novae and meteors were thought to be in the Earth’s atmosphere.
03/25/2019 – Ephemeris – Zodiacal light is visible in the west again
Ephemeris for Monday, March 25th. Today the Sun will be up for 12 hours and 24 minutes, setting at 8:01, and it will rise tomorrow at 7:35. The Moon, 3 days before last quarter, will rise at 1:37 tomorrow morning.
With the bright moon out of the sky for nearly two weeks it’s time to look for the zodiacal light. It’s is a faint but towering glow that can be seen after the end of astronomical twilight on moonless nights. It is seen in the west in the evening in late winter and early spring and in the east in the morning in late summer and early autumn. The axis of the glow is the ecliptic, the apparent annual path of the Sun in the sky, along which lie the constellations of the zodiac. Right now the end of astronomical twilight is about 9:45 p.m. and advancing at a rate of a minute or two each night. Go to a spot with a dark western sky, no big cities or towns out that way. Zodiacal light is caused by dust spread out around the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Much enhanced Zodiacal Light from the my back yard at 9:31 p.m. March 16, 2018, 5 minutes after the official end of astronomical twilight. Note the Pleiades top left of center and the constellation of Ares below and right of center. Canon EOS Rebel T5 18mm f.l., f/3.5, 6 sec. ISO 12,800 . The clouds on the left appear to be illuminated by the lights of the towns of Beulah and Frankfort 20+ miles away.
I’ve added the approximate ecliptic line from a Stellarium view of the same date and time.
03/22/2019 – Ephemeris – The Great Underwater Panther
Ephemeris for Friday, March 22nd. Today the Sun will be up for 12 hours and 14 minutes, setting at 7:57, and it will rise tomorrow at 7:40. The Moon, 2 days past full, will rise at 10:07 this evening.
The Anishinabe peoples of the Great Lakes Region, which includes the Ottawa, Chippewa and Ojibwe Indians have one constellation of winter I know of. It is The Winter Maker which uses many of Orion’s stars and whose arms stretch from Aldebaran in Taurus the bull to Procyon the Little Dog Star, embracing the whole of the winter sky. Now that spring is here he is sinking into the west. The first constellation of spring is Curly Tail, or the Great Underwater Panther. Which uses the stars of Leo the lion’s backward question mark as its tail and the small knot of stars that are the head of Hydra the water snake below Cancer the crab as its head. Keep off the thinning ice or break through and be snatched by the great panther that lives below.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Great Underwater Panther finder animation relating western to Anishinaabe constellations for 9 p.m. March 22, 2019. Click on the image to enlarge. Created using Stellarium.
The constellation art is part of the latest versions of Stellarium. Ojibwe (Anishinaabe) constellation art by Annette S Lee and William Wilson from Ojibwe Sky Star Map Constellation Guide, by A. Lee, W Wilson, C Gawboy, J. Tibbetts. ISBN 978-0-615-98678-4.
03/21/2019 – Ephemeris – Are day and night really equal at the equinoxes?
Ephemeris for Thursday, March 21st. Today the Sun will be up for 12 hours and 11 minutes, setting at 7:56, and it will rise tomorrow at 7:42. The Moon, 1 day past full, will rise at 8:52 this evening.
What we had yesterday was the vernal equinox, the start of spring. The word equinox means “equal night”. Yesterday’s daylight hours were 12 hours and 8 minutes. What’s with the 8 minutes? The rising or setting Sun is a mirage. The Earth’s atmosphere acts like a lens and makes the Sun appear higher in the sky than when it is when near the horizon. When the bottom edge of the Sun touches the horizon the Sun is actually still completely below the horizon geometrically. If the Earth had no atmosphere sunrises would occur 4 minutes later, and sunsets would occur 4 minutes earlier around here. That would completely correct the 12 hour 8 minutes daylight time of yesterday to 12 hours even.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
How the atmosphere bends the light of the Sun or Moon rising or setting to appear higher than it actually is. Credit Francisco Javier Blanco González, 2017.
I took a look at the related atmospheric refraction effect last month: https://bobmoler.wordpress.com/2019/02/19/02-19-2019-ephemeris-the-moon-aint-just-super-near-the-horizon/.
03/20/2019 – Ephemeris – The first look, of spring, at the bright planets
Ephemeris for Wednesday, March 20th. Today the Sun will be up for 12 hours and 8 minutes, setting at 7:55, and it will rise tomorrow at 7:44. The Moon, at full today, will rise at 7:35 this evening.
Let’s look at the planets for this week. Looking down we see the Earth which will reach a point in its orbit at 5:58 p.m. (21:58 UT) where spring will start. Mars will be in the west-southwestern sky this evening. It will set at 12:37 a.m. Mars is fading as the Earth, in its inner and faster orbit is leaving Mars behind. In the morning sky we have Jupiter which will rise tomorrow at 2:55 a.m. in the east-southeast It is second to Venus in brightness. Saturn will be next to rise at 4:40 a.m., also in the east-southeast. Venus will rise at 6:26 a.m. also in the east-southeast By 7 in the morning they will be strung out from the southeast to the south. They will be a beautiful sight as morning twilight advances.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars and the Moon and the bright stars on the first day of spring at 9 p.m. March 20, 2019. Click on the image to enlarge. Created using Stellarium.
The full moon, and super moon at that, at 9 p.m. March 20, 2019. Created using Stellarium.
Morning planets and the constellations at 7 a.m. tomorrow March 21, 2019. Created using Stellarium.
Jupiter, Saturn and Venus with the same magnification at 7 a.m. tomorrow morning March 21, 2019. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 20, 2019. The night ends on the left with sunrise on the 21st. Note the motion of the Moon from sunrise and sunset. Click on the image to enlarge. Created using my LookingUp program.
03/19/2019 – Ephemeris – Spring and a super-moon happen tomorrow
Ephemeris for Tuesday, March 19th. Today the Sun will be up for 12 hours and 5 minutes, setting at 7:53, and it will rise tomorrow at 7:46. The Moon, 1 day before full, will set at 7:55 tomorrow morning.
Today and tomorrow are busy days, astronomically speaking, for the Earth, Sun and Moon. This afternoon at 3:47 the Moon will reach the perigee point in its orbit of the Earth, its closest point of 223,200 miles (359,400 km) center to center. With the full moon just 30 hours later this will make the Moon a super-moon, the third in a row. The Moon will be full enough to call tonight’s moon a super-moon too when it rises around 6:16 p.m. The next event will be the coming of spring, when the Sun appears to cross the celestial equator heading northward. For a point in the Pacific Ocean, on the equator the Sun will be directly overhead at 5:58 p.m. our time or 21 hours, 58 minutes Universal Time or Greenwich Mean Time.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mini Moon and Super Moon for 2017. Trouble is the Moon appears alone with nothing to compare it to when it is seen in the sky. Created using Cartes du Ciel (Sky Charts).
The Sun’s path through the sky on the equinox day from Traverse City, MI. Created using my LookingUp program. (This is from a couple of years ago. The actual length of daylight depends on when during the day the moment of the equinox occurs. I’ll have more on that Thursday.)
03/18/2019 – Ephemeris – Spring, the full moon and Easter
Ephemeris for Monday, March 18th. Today the Sun will be up for 12 hours and 2 minutes, setting at 7:52, and it will rise tomorrow at 7:48. The Moon, 2 days before full, will set at 7:21 tomorrow morning.
Spring is two days away. In checking my astronomical calendars I noticed an odd thing related to the date of Easter for western churches. If I said that the date of Easter was the first Sunday after the first full Moon after the vernal equinox. I’d be wrong. Even if I replaced vernal equinox with first day of spring, I would still be wrong by ecclesiastical standards. The ecclesiastical vernal equinox is March 21st, no matter what. Plus the full moon date is a tabulated value and not necessarily the astronomical full moon date. This year the astronomical first full moon of spring falls less than 4 hours after the astronomical vernal equinox on March 20th. Therefore Easter will be late this year on April 21st, 4 days earlier than its latest possible date.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Bob Moler's Ephemeris Blog 