Archive

Posts Tagged ‘Betelgeuse’

02/11/2021 – Ephemeris – The Winter Triangle

February 11, 2021 Comments off

This is Ephemeris for Thursday, February 11th. Today the Sun will be up for 10 hours and 17 minutes, setting at 6:06, and it will rise tomorrow at 7:47. The Moon is new today, and won’t be visible.

I usually talk about the Winter Circle of bright stars, 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 event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Winter triangle finder animation

Winter Triangle finder animation. It shows the star field, named first magnitude stars, then their constellations, then the Winter Triangle and constellations of the three stars. Click on the image to enlarge. Created using Stellarium and GIMP.

01/26/2021 – Ephemeris – A look at the bright red giant star Betelgeuse

January 26, 2021 Comments off

This is Ephemeris for Tuesday, January 26th. Today the Sun will be up for 9 hours and 35 minutes, setting at 5:43, and it will rise tomorrow at 8:06. The Moon, 2 days before full, will set at 7:38 tomorrow morning.

At 8 pm the constellation of Orion the hunter is in the southeastern sky. The bright reddish star at the top left of Orion’s distinctive seven-star pattern is Betelgeuse a star near the end of its life. Being a single bright star, its distance is not well determined and is estimated to be about 550 light years away with an uncertainty of up to 20 percent, which make other estimates that uncertain too, like its mass and diameter. It’s somewhat less than 20 times the mass of the Sun, and a diameter possibly as large as Jupiter’s orbit of the Sun. It is old for a star of its mass, probably 8 million years old, with up to a million years to go on the outside before it will probably explode as a supernova and grace our skies as bright as the Moon for the better part of the better part of a year.

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

Addendum

Orion

The seven brightest stars of Orion in the south-southeast at 8 p. in late January.

Betelgeuse drawing

“This artist’s impression shows the supergiant star Betelgeuse as it was revealed thanks to different state-of-the-art techniques on ESO’s Very Large Telescope, which allowed two independent teams of astronomers to obtain the sharpest ever views of the supergiant star Betelgeuse. They show that the star has a vast plume of gas almost as large as our Solar System and a gigantic bubble boiling on its surface. These discoveries provide important clues to help explain how these mammoths shed material at such a tremendous rate. The scale in units of the radius of Betelgeuse as well as a comparison with the Solar System is also provided.” Credit: ESO/L. Calçada (ESO is the European Southern Observatory)

12/28/2020 – Ephemeris – Some astronomical events of 2020

December 28, 2020 Comments off

This is Ephemeris for Monday, December 28th. Today the Sun will be up for 8 hours and 50 minutes, setting at 5:09, and it will rise tomorrow at 8:19. The Moon, 1 day before full, will set at 8:01 tomorrow morning.

Let’s look at some astronomical and space news for this past year. A year ago the bright red star in the constellation Orion Betelgeuse underwent an unprecedented amount of dimming. It had pretty much recovered its brightness since. The best idea was that it ejected a cloud of dust that obscured part of the star from us. NASA’s Commercial Crew program came through this year with the successful launching of two crews to the International Space Station aboard the SpaceX Falcon 9 rocket and Crew Dragon Capsule. Boeing stood down this year after the failure of their uncrewed Starliner capsule to reach the space station last December. They will try another uncrewed attempt in a few months. I’ll have more tomorrow.

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

Addendum

Orion's named stars

Orion’s named stars including the belt stars. Betelgeuse is the bright red in the upper left. 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. Betelgeuse is one of the few stars close and large enough to be able to image its disk. Credit: ESO/M. Montargès et al.

SpaceX Crew-1 Crew

Astronauts Shannon Walker, Victor Glover, and Mike Hopkins, and astronaut Soichi Noguchi inside the Crew Dragon capsule. Credit: SpaceX.

SpaceX Crew-1 Dragon capsule docking with the International Space Station

SpaceX Crew-1 Dragon capsule docking with the International Space Station. Credit: NASA

 

 

 

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: ,

12/07/2020 – 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

 

 

02/20/2020 – Ephemeris – The Winter Triangle

February 20, 2020 Comments off

Ephemeris for Thursday, February 20th. Today the Sun will be up for 10 hours and 41 minutes, setting at 6:17, and it will rise tomorrow at 7:34. The Moon, 3 days before new, will rise at 6:53 tomorrow morning.

I usually talk about the Winter Circle of bright stars, 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 equally invisible constellation of Monoceros the unicorn. The Summer Triangle has three bright stars with no other close competition. The Winter Triangle has 4 other bright stars near it. Any three of these would make a nice triangle. One of these stars, Betelgeuse has been the news recently because it is dimming to an unprecedented degree.

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

Addendum

Winter Triangle

The Winter Triangle. It enclose a pretty blank space where Monoceros the unicorn lies. Created using Stellarium with my annotations for the Winter Triangle. By the way, Betelgeuse is currently only as bright as Bellatrix, the star next to the “n” in Orion.

02/17/2020 – Ephemeris – A look at Orion and his hunting dogs

February 17, 2020 Comments off

Ephemeris for President’s Day, Monday, February 17th. Today the Sun will be up for 10 hours and 32 minutes, setting at 6:13, and it will rise tomorrow at 7:39. The Moon, 2 days past last quarter, will rise at 4:27 tomorrow morning.

The great winter constellation or star group Orion the Hunter, is located in the southern sky at 9 p.m. His elongated rectangle of a torso is vertical. In the center of the rectangle are three stars in a line that make his belt. As a hunter, especially one of old, he has two hunting dogs. The larger, Canis Major can be found by following the three belt stars of Orion down and to the left. There lies the brilliant star called Sirius, also known as the Dog Star. It’s in the heart of a stick figure dog lower in the south facing Orion that appears to be begging. Canis Minor is just two stars found by extending Orion’s shoulder stars eastward where we find bright Procyon, the little dog star in the southeast.

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

Addendum

Orion and his hunting dogs

Orion and his hunting dogs with pointers as seen at 9 p.m. in mid February. Created using Stellarium.

01/02/2020 – Ephemeris – Orion’s great red star Betelgeuse is dimming

January 2, 2020 Comments off

Ephemeris for Thursday, January 2nd. The Sun will rise at 8:20. It’ll be up for 8 hours and 53 minutes, setting at 5:13. The Moon, at first quarter today, will set at 12:48 tomorrow morning.

The bright red giant star in the constellation Orion’s shoulder is in the news. It is dimming, and it is dimmer now than it has been for a very long time. A chart by the American Association of Variable Star Observers shows that this is the dimmest it’s been going back to 1970 and maybe a long time before that. Betelgeuse was first noticed to vary in brightness in 1838. It is the left star at the top of Orion’s upright rectangle of stars. Bellatrix is the right corner star. Betelgeuse is now only a little brighter than it, and much dimmer than Rigel the lower right corner star. A couple of years ago it was brighter than it had been since 1970. Astronomers are watching and waiting. They expect Betelgeuse to explode as a supernova sometime in the next million years.

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

Addendum

Orion's brightest stars

Orion’s brightest stars with their names for 9 p.m. January 7. Click on the image to make Orion a giant hunter. Created using Stellarium, which shows Betelgeuse at its average magnitude of 0.45.

Orion and Betelgeuse

Orion and Betelgeuse on Christmas night 2019 by David Dickinson. Photo from a smart phone from Virginia Beach. Note that Betelgeuse is not much brighter than Bellatrix and much dimmer than Rigel.

Magnitude estimates of Betelgeuse

Magnitude estimates of Betelgeuse since 1970. Credit AAVSO.

Note on the magnitude scale:  The lower the magnitude the brighter the star.  Stars with magnitudes less than 1.5 are first magnitude stars.  Second magnitude stars are between 1.5 and 2.5, and so on.

For more information check out Universe Today: https://www.universetoday.com/144465/waiting-for-betelgeuse-whats-up-with-the-tempestuous-star/

And Dr. Phil Plait’s Bad Astronomy: https://www.syfy.com/syfywire/dont-panic-betelgeuse-is-almost-certainly-not-about-to-explode

Categories: Ephemeris Program, Stars Tags: