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10/31/2018 – Ephemeris – The bright planets tonight
Ephemeris for Halloween, Wednesday, October 31st. The Sun will rise at 8:19. It’ll be up for 10 hours and 13 minutes, setting at 6:32. The Moon, at last quarter today, will rise at 1:02 tomorrow morning.
Let’s look at the bright planets for tonight. Three of them are visible in the evening sky. Jupiter will be barely visible very low in the west-southwest after sunset. It will set at 7:30 p.m. Saturn, the ringed planet, will start the evening low in the south-southwestern sky and will set at 9:49 p.m. Mars will be low in the south-southeast as the skies darken tonight. and is now 73.2 million miles (117.9 million km) away. Mars will be due south at 8:39 p.m., and it will set at 1:33a.m. Mars is picking up speed moving eastward, crossing the constellation of Capricornus this month. It’s currently in eastern Capricornus. Venus, now a morning planet, will rise at 7:45 tomorrow morning, 34 minutes after the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Update
I know, the content above isn’t very spooky for Halloween. However, NASA came to the rescue with their Halloween Special: Universe of Monsters. Fitting with our theme today, it’s about planets… of the Exo variety. Click here!
10/31/2014 – Ephemeris – The spookiest star
Ephemeris for Halloween, Friday, October 31st. The sun will rise at 8:18. It’ll be up for 10 hours and 13 minutes, setting at 6:32. The moon, 1 day past first quarter, will set at 1:59 tomorrow morning.
Not all the ghosts and goblins out Sunday will be children. One will be out every night, because it’s a star. Its name is Algol, from the Arabic for Ghoul Star or Demon Star. The Chinese had a name for it that meant “piled up corpses”. It’s the second brightest star in the constellation Perseus the hero, rising in the northeast this evening. The star is located where artists have drawn the severed head of Medusa, whom he had slain. Medusa was so ugly that she turned all who gazed upon her to stone. Algol is her still glittering eye. Astronomers finally found out what was wrong with Algol. It does a slow 6 hour wink every two days 21 hours, because it is two stars that eclipse each other. Her next wink will be 10 p.m. Sunday night.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Perseus and the head of Medusa from the 1690 Uranographia by Johannes Hevelius. Image found with the article on Algol in Wikipedia.
Celestial globes of the day showed the celestial sphere from the outside, so the constellations appeared reversed. The star atlases of the day kept the trend. I reversed the image to correspond with the actual sky.
Algol at 7:30 p.m. on Halloween, in a modern portrayal. Created using Stellarium.
Update
Animation of an eclipsing binary star like Algol. Credit: Wikimedia Commons. H/T EarthSky
Here’s a link to EarthSky’s post on Algol.
Bob Moler's Ephemeris Blog 