Algol

Tiny points of light, with a magic all their own.
Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Algol

Post by Christopher K. » October 5th, 2015, 2:55 pm

The Demon Star!

Beta Persei is one of the most famous stars in the Northern Hemisphere. It is a triple star system. The two main stars are class B and class K. Every two days, twenty hours and forty-nine minutes (roughly), the light of the B-star is mostly blocked out, resulting in a fantastic dimming of Algol which can be spotted with unaided eyes.

More information:
Celestial Handbook by Robert Burnham, pp. 1409-1419.
http://stars.astro.illinois.edu/sow/algol.html
http://www.daviddarling.info/encyclopedia/A/Algol.html

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » October 15th, 2015, 5:56 pm

Below are the predicted Baton Rouge times during which Algol is at its dimmest--the term is minima. The predictions came from the AAVSO, via Sky & Telescope. The times are the midpoint of a rough two-hour period of dimness.
15 October, 8:50pm
18 October, 5:39pm
21 October, 2:29pm
24 October, 11:16am
27 October, 8:05am
30 October, 4:54am

One will notice a well-placed time tonight. If a view is gotten at 8:50pm, try looking again at 9:50pm and 10:50pm. Even 11:50pm...I can understand someone staying out until about 12:30am to take advantage of this night's fine qualities.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » November 18th, 2015, 8:19 pm

I followed my own advice and on 15 October I looked at Algol twice with a Bushnell 10x. At 9:42pm it certainly was near minimum--it was as bright as Rho Persei (a magnitude 3.3 K-class star). As an added bonus for hopping from Almach to get to Algol, I spotted the faint outline of magnitude 5.2 cluster M34.

I returned to Algol at 10:42pm. Since it was only an hour later, it had only brightened marginally.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » December 15th, 2015, 6:18 pm

Algol will be its highest tonight at ~9:35pm. I guess since this is an "evil" star, none of its time should have greater evil influence over an area of Earth than its culmination! It will be at minimum Thursday night from ~9:48pm to 11:48pm CST.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » December 26th, 2015, 6:21 pm

Algol's last minimum of the year is predicted for Tuesday at 6:04am, which is no good for viewing the brightening. Hopefully some January minima will occur during nighttime in Baton Rouge.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » December 31st, 2015, 9:11 am

Below are the predicted Baton Rouge times during which Algol is at its dimmest during January 2016. The predictions came from the AAVSO, via Sky & Telescope. The times are the midpoint of a rough two-hour period of dimness.
1 January, 3:53am
4 January, 12:42am
6 January, 9:31pm
9 January, 6:20pm
12 January, 3:09pm
15 January, 11:59am
18 January, 8:48am
21 January, 5:37am
24 January, 2:26am
26 January, 11:16pm
29 January, 8:05pm
(All times are Central Standard.)
One can easily discern a pattern. One then also realizes that due to the fairly long stretches of daytime minima, the brightening of Algol should be viewed when possible.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » November 25th, 2016, 6:14 pm

Algol is predicted to reach minima (3.4 in magnitude, remember) tonight at 11:13pm CDT. The variable will be a well-placed seventy-eight degrees up in the north-northwest at that time.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » January 30th, 2017, 2:17 pm

Algol is predicted to reach minima (magnitude 3.4) tonight from 9:04pm to 11:04pm CST. At 10:04pm Algol will be forty-six degrees up in the northwest. This is an opportune time with a clear sky and a night with no freezing temperatures.

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » February 16th, 2017, 4:10 pm

There are only three good weeks left to view this famous star. The Moon doesn't rise until after 11pm tonight, so take a look. I'll be practicing my variable estimation technique (such as it is).

Christopher K.
Posts: 4772
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Algol

Post by Christopher K. » March 18th, 2017, 5:19 pm

Algol will be at its minimum magnitude of 3.4 from 7:14pm to 9:14pm tonight; unfortunately it doesn't get completely dark until 8:38pm; at that time Algol will be thirty-seven degrees up in the northwest.

The Moon will be below the horizon.

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