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Posts Tagged ‘Orion’

01/15/2021 – Ephemeris – The constellation Lepus the hare

January 15, 2021 Leave a comment

This is Bob Moler with Ephemeris for Friday, January 15th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:28, and it will rise tomorrow at 8:15. The Moon, 2 days past new, will set at 8:17 this evening.

Orion, the central winter constellation is seen in the southern sky this evening. He is a hunter, as artists depict him, he is preoccupied with the charge of Taurus the bull from the upper right. At Orion’s feet, and unnoticed by him is the small constellation of Lepus the hare. It’s very hard to see a rabbit in its eight dim stars: however, I can see a rabbit’s head ears and shoulders. A misshapen box is the head and face of this critter facing to the left. His ears extend upwards from the upper right star of the box, and the bend forward a bit. Two stars to the right of the box and a bit farther apart hint at the front part of the body. In Lepus telescopes can find M79, a distant globular star cluster, one of the few visible in the winter sky.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

My view of Lepus the hare.

My view of Lepus the hare. Star field from Cartes du Ciel. Desert Cottontail drawing from Arizona-Senora Desert Museum website. Superimposed with GIMP.

Lepus

An animation showing the stars, constellations and artwork of Lepus, Orion and Taurus from Stellarium. The constellation lines suggest a rabbit ears TV antenna. Created using Stellarium and GIMP.

01/12/2021 – Ephemeris – The celestial river Eridanus

January 12, 2021 Leave a comment

This is Bob Moler with Ephemeris for Tuesday, January 12th. Today the Sun will be up for 9 hours and 7 minutes, setting at 5:25, and it will rise tomorrow at 8:17. The Moon, 1 day before new, will rise at 8:58 tomorrow morning.

One of the more obscure constellations around is Eridanus, which depicts a river. The river starts near the lower right corner of Orion, near the bright star Rigel and flows to the right then down near the southwestern horizon, then it meanders along the horizon to the south before turning below the horizon. One has to travel to the far south to see the southern terminus of the river, the bright star Achernar. Writers over the ages have seen here the Nile and the Earth circling river Ocean of the flat earth days. Achernar is actually two stars, the brightest was discovered to be the flattest star known, due to its rapid spin. The dimensions of Achernar A has been determined to be twice as wide across its equator than from pole to pole. It’s 139 light years away.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Eridanus

An animation of the constellation Eridanus which is a river that flows from Rigel in Orion to the star Achernar below our southern horizon at latitude 45 degrees north. Create using Stellarium and GIMP.

01/11/2021 – Ephemeris – Procyon, the before the Dog Star

January 11, 2021 Comments off

This is Bob Moler with Ephemeris for Monday, January 11th. Today the Sun will be up for 9 hours and 5 minutes, setting at 5:23 pm, and it will rise tomorrow at 8:17 am. The Moon, 2 days before new, will rise at 8:05 tomorrow morning.

Visible low in the east at 8 p.m. appears the star Procyon. To its right and below is Sirius the brightest night-time star. Procyon is the bright star in the constellation Canis Minor, or lesser dog. I can find only one other star in Canis Minor. Perhaps it’s a hot dog. If Sirius, in Canis major is the Dog Star then Procyon should be the Little Dog Star. However, Procyon is an interesting name. It means “Before the dog”, which is an allusion to the fact that Procyon, though east of Sirius actually rises before it. This is due to Procyon’s more northerly position. This effect doesn’t work south of the equator, however. Sirius will rise at about 7:30 tonight. Procyon is a star much like Sirius but is 32% farther away. It’s 11.4 to Sirius’ 8.6 light years away.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Orion and his hunting dogs in early winter

Orion and his hunting dogs in early winter (8 pm, January 11, 2021) showing that Procyon does rise before Sirius.

01/07/2021 – Ephemeris – The constellations Orion and Taurus interact

January 7, 2021 Comments off

This is Bob Moler with Ephemeris for Thursday, January 7th. Today the Sun will be up for 8 hours and 59 minutes, setting at 5:19, and it will rise tomorrow at 8:19. The Moon, 1 day past last quarter, will rise at 3:13 tomorrow morning.

There are several instances in the Greek heavens where constellations appear to interact with one another. This is true with Orion the hunter and Taurus the bull. Taurus, whose face is the letter V of stars with orangish Aldebaran as his angry bloodshot eye is charging down on Orion, who has raised a lion skin shield on one arm and an upraised club in the other, ready to strike. They have been frozen in this pose for millennia. Stars below and right of the letter V of the Bull’s face suggest the front part of his body and his front legs charging at Orion. Orion also has two hunting dogs, Canis Major and Canis Minor. Canis Major with its dazzling star Sirius will rise around 7:30 on a line extended down from Orion’s belt.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

The Orion-Taurus Tableau. Seen around 8 pm, January 7, 2021. Created using Stellarium.

Categories: Constellations Tags: ,

01/05/2021 – Ephemeris – Orion’s named stars and their meanings

January 5, 2021 Comments off

This is Ephemeris for Tuesday, January 5th. Today the Sun will be up for 8 hours and 57 minutes, setting at 5:17, and it will rise tomorrow at 8:19. The Moon, 1 day before last quarter, will rise at 12:42 tomorrow morning.

The constellation of Orion the hunter is visible in the southeast at 8 p.m. The names of the stars of Orion are interesting in themselves. Starting at the top left of the seven bright stars of Orion’s torso is Betelgeuse the bright red star, whose name means something like “Armpit of the Giant”. The star in Orion’s other shoulder is Bellatrix the “Amazon Star”. Below are the three stars of Orion’s belt, from left to right; Alnitak, Alnilam and Mintaka. Their names mean “Girdle”, “Belt of Pearls”, and “Belt” respectively. Down to Orion’s knees we look on the left to the star Saiph pronounced “Safe”* which means “Sword”, though it is a star in his knee. Finally, there’s the bright blue-white star Rigel whose name means “Left Leg of the Giant” in Orion’s other knee. These are the important stars that make up the figure of Orion in the sky. [BTW. most star names are Arabic, and what survives of them is just a part of the original Arabic phrases.]

* In the radio program I pronounced the word then spelled it out.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Orion with star names.

The named stars of Orion. Created using Stellarium.

Categories: Constellations, Star Names Tags:

12/17/2020 – Ephemeris – Betelgeuse, Betelgeuse… Nope not saying it again

December 17, 2020 Comments off

This is Bob Moler with Ephemeris for Thursday, December 17th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:03, and it will rise tomorrow at 8:15. The Moon, 3 days past new, will set at 8:18 this evening.

The constellation Orion the hunter will have completely risen by 8 pm this evening. The leftmost bright red star in his shoulder is Betelgeuse. It’s phonetically spelled name (Beetle Juice) made the title of a movie in 1988. A year ago it’s dramatic dimming for a while caused some to wonder that it was about to explode in a supernova. Betelgeuse does normally vary a bit in brightness, but that was the most ever recorded. It’s a red giant star with a mass of 16 to 19 times the Sun’s. Its distance is thought to be about 550 light years away. It is difficult to measure the distance of single bright stars, even with satellites. Its age is maybe 8 to 8 ½ million years old out of a life expectancy of 10 million years, compared to the Sun’s 10 billion year life expectancy.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Orion

Orion at 8 pm or about 3 hours after sunset in mid December. Its seven brightest stars make an unmistakable pattern with only Betelgeuse and Rigel labeled. Created using Stellarium.

Betelgeuse before and after dimming

This comparison image shows the star Betelgeuse before and after its unprecedented dimming. The observations, taken with the SPHERE instrument on ESO’s Very Large Telescope in January and December 2019, show how much the star has faded and how its apparent shape has changed. Credit: ESO/M. Montargès et al.

Betelgeuse's dust plume

An image of the star Betelgeuse taken in infrared shows it’s surrounded by a vast cloud of dust that erupted from the surface (the bright star itself is masked out, though an image of it has been superposed there for scale — the star is about the size of the orbit of Jupiter, over a billion km wide). Credit: ESO/P. Kervella/M. Montargès et al., Acknowledgement: Eric Pantin via Phil Plait’s Bad Astronomy blog on syfy.com.

Categories: Ephemeris Program, stars Tags: ,

12/08/2020 – Ephemeris – Finding Taurus the bull

December 8, 2020 Comments off

This is Ephemeris for Tuesday, December 8th. Today the Sun will be up for 8 hours and 54 minutes, setting at 5:02, and it will rise tomorrow at 8:08. The Moon, 1 day past last quarter, will rise at 1:39 tomorrow morning.

Orion is the big splashy constellation in the east southeast by 9 in the evening. Above it is another famous constellation Taurus the bull. Its face is a letter V shape of stars on its side with the open end of the V to the left. The bright star at the lower left end of the sideways V is the ruddy star Aldebaran, the Bull’s angry bloodshot eye. The bull is charging down at Orion. The Pleiades, also known as the seven sisters, is the cluster of stars in his shoulder, above the V. The stars in the face of Taurus, except for Aldebaran belong to a star cluster like the Pleiades, but closer and older, called the Hyades. In Greek mythology the Hyades are half sisters to the Pleiades, all fathered by the god Atlas.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Taurus and Orion

Three views of Taurus the bull and Orion the hunter for 9 p.m. on December 8th. Created using Stellarium and GIMP.

Hyades and Pleiades

The Pleiades (right) and the Hyades (left) in this photograph I took January 4, 2016. The orientation is a bit different from how it appears in early December.

12/07/2020 – Ephemeris – Looking forward to the best of winter: Orion

December 7, 2020 Comments off

This is Ephemeris for Monday, December 7th. Today the Sun will be up for 8 hours and 55 minutes, setting at 5:02, and it will rise tomorrow at 8:07. The Moon, at last quarter today, will rise at 12:25 tomorrow morning.

Orion, the central constellation of the winter evening sky will be completely risen by 9 this evening. Then it can be seen low in the east-southeast it’s upright rectangle of stars tilted to the left. The topmost star to the left in this rectangle is the famous red giant star Betelgeuse, which is reportedly dimming again. It’s in Orion’s shoulder. In his other shoulder is Bellatrix, a name known to Harry Potter fans. In his knees are Rigel, a blue-white giant star and Saiph. In the center of the rectangle are three stars in a straight line, now almost vertically arranged, Orion’s belt. And below his belt what seem to be three more stars, his sword. In the center of the sword stars can be found, with binoculars or telescope, Orion’s most famous feature, the Great Orion Nebula.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Orion early December finder animation

Orion early December finder animation for 9 pm December 7th. Created using Stellarium and GIMP.

Orion's named stars

Orion’s named stars including the belt stars. Cursa, though named belongs to the neighboring constellation Eridanus the river. Created using Stellarium.

03/05/2020 – Ephemeris – Apparently Betelgeuse, though dimming wasn’t cooling as expected

March 5, 2020 Comments off

Ephemeris for Thursday, March 5th. Today the Sun will be up for 11 hours and 24 minutes, setting at 6:36, and it will rise tomorrow at 7:10. The Moon, 3 days past first quarter, will set at 5:31 tomorrow morning.

Betelgeuse, the red star in the constellation Orion’s shoulder has apparently stopped dimming and has begun to brighten. The guesses as to the cause of the dimming are many. One suggested by a photograph taken of the star in December shows the southern half dimmed like it was covered by something. Betelgeuse out gasses lots of material, some of which condenses into dust. Could some of this dust mask the star and make it dimmer? I suspect that we’ll find out before too long. Many astronomers are wishing Betelgeuse would explode in a core collapse or type 2 supernova. At its approximate 700 light year distance we’d be safe, though a bazillion neutrinos would pass harmlessly through each one of us just before the light would get here.

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

Addendum

Betelgeuse's dust plume

An image of the star Betelgeuse taken in infrared shows it’s surrounded by a vast cloud of dust that erupted from the surface (the bright star itself is masked out, though an image of it has been superposed there for scale — it’s about the size of the orbit of Jupiter, over a billion km wide). Credit: ESO/P. Kervella/M. Montargès et al., Acknowledgement: Eric Pantin via Phil Plait’s Bad Astronomy blog on syfy.com.

Betelgeuse before and after dimming

This comparison image shows the star Betelgeuse before and after its unprecedented dimming. The observations, taken with the SPHERE instrument on ESO’s Very Large Telescope in January and December 2019, show how much the star has faded and how its apparent shape has changed. Credit: ESO/M. Montargès et al.

More on this from Dr. Phil Plait’s Bad Astronomy blog on syfy.com: https://www.syfy.com/syfywire/mea-culpa-betelgeuse-and-its-dusty-convective-pulsations

Categories: Ephemeris Program, stars Tags: ,

03/03/2020 – Ephemeris – Betelgeuse, apparently, has stopped dimming and may be brightening

March 3, 2020 Comments off

Ephemeris for Tuesday, March 3rd. Today the Sun will be up for 11 hours and 18 minutes, setting at 6:33, and it will rise tomorrow at 7:14. The Moon, 1 day past first quarter, will set at 3:41 tomorrow morning.

Betelgeuse the red giant star in the constellation Orion’s shoulder has apparently stopped dimming and may be brightening again. The process of recovery is slow. It may recover its former brightness. We’ll know this later in summer when Betelgeuse and the rest of Orion moves from behind the Sun and enters the morning sky. Betelgeuse is known to be irregular in brightness, but has never been recorded as being this dim, dropping it from being a first magnitude star. Betelgeuse is no longer dimming. There is lots of speculation as to why it’s now brightening. One is the thought that there are several periodic cycles that govern Betelgeuse’s variability. That the troughs of these cycles happen to coincide is one explanation.

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

Addendum

Orion at 7:07 p.m. January 6, 2020

Betelgeuse in Orion (the bright star on the left) at 7:07 p.m. January 6, 2020. Taken with my Samsung Galaxy S10+ in the moonlight. Compare the brightness of Betelgeuse with Rigel, Bellatrix and the belt stars.

The brightness of Betelgeuse from late November 2019 to 23 Feb. 2020 shows it dimming dramatically (the y-axis is in magnitudes, where a bigger number is fainter). A close-up on just the past 20 days (right) shows it starting to rise again around 18 Feb. Blue dots are estimates by eye, black using digital cameras, and the red line is a smooth fit to the data. Credit: Betelbot on Twitter, run by Michael Hipke via Dr. Phil Plait’s Bad Astronomy post https://www.syfy.com/syfywire/no-supernova-for-you-betelgeuse-is-brightening-again-right-on-schedule