Archive for January 10, 2019

01/10/2018 – Ephemeris – Betelgeuse the red giant star in the giant hunter Orion’s shoulder

January 10, 2019 Comments off

Ephemeris for Thursday, January 10th. The Sun will rise at 8:18. It’ll be up for 9 hours and 3 minutes, setting at 5:22. The Moon, 4 days before first quarter, will set at 9:55 this evening.

The bright red star at the upper left corner of the constellation Orion, high in the southeast at 9 p.m. is Betelgeuse. The name is a contraction of an Arabic phrase that means “Armpit of the Central One”. Betelgeuse is a huge star with a diameter four times that of the earth’s orbit of the sun. It is throwing of gas and creating a nebula around itself. It’s distance from us isn’t accurately known, since it doesn’t have a companion star. It’s about 640 light years away, give or take 148 light years or so. Betelgeuse is about 18 times the mass of the sun and 140 thousand times brighter. It is in the latter stages of its short life,of 10 million year so far. Within another million years or so it will probably explode in a supernova.

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


Orion's brightest stars

Orion’s brightest stars with their names for 9 p.m. January 7, 2019. Click on the image to make Orion a giant hunter. Created using Stellarium..

Betelgeuse disk

This is the disk of the star Betelgeuse in Orion. It is not an image from an optical telescope of an image created in submillimeter microwaves by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. Credit: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella

Betelgeuse and its nebula. From ESO's Very Large Telescope.

Betelgeuse (inset) and its nebula. From ESO’s Very Large Telescope.