Andromeda Galaxy (M31)

The Milky Way is but one of billions.
Post Reply
Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Andromeda Galaxy (M31)

Post by Christopher K. » July 2nd, 2013, 7:05 pm

Of all galaxies save our own, this is probably the one that inspires basic amateurs to "cross the line" from Solar System locales to deep-sky stuff. Many, I'm sure, think of tackling M31 before even some double stars. Tenth-century author Al Sufi called it "the Little Cloud" in the Book of Fixed Stars and that's what can be seen if one is in a dark area. At this time we believe M31 is less massive than the Milky Way, though it's larger.

Simon Marius performed telescopic observations of M31 by at least 1612, calling it "the light of a candle shining through horn". In 1923, Edwin Hubble detected cepheid variable stars in the "Andromeda Nebula" and established the object as being its own "island universe" outside the Milky Way. The first detection of radio waves from an external galaxy was from M31 in 1950, using the largest paraboloidal antenna in existence at the time.

Andromeda is a third- or fourth-magnitude object (3.4 from Pennington, 4.4 from Darling), tilted only about seventeen degrees from face-on. In Moonless dark skies, it is an easy target for small telescopes. Users of large telescopes should use low power, as M31 is over four degrees in diameter. According to Dickinson, "The best views are with a pair of oversized binoculars or a telescope with a 2-inch focuser and a 30mm-to-40mm 2-inch eyepiece, which places the galaxy in a two-degree or wider field."

Below are the time during which M31 reaches it highest altitude of seventy-nine degrees in the Baton Rouge sky...
20 August = 3:52am CDT
24 August = 3:37am CDT
28 August = 3:21am CDT
1 September = 3:05am CDT
5 September = 2:49am CDT
9 September = 2:34am CDT
13 September = 2:18am CDT
17 September = 2:02am CDT
21 September = 1:47am CDT
25 September = 1:31am CDT
29 September = 1:15am CDT
3 October = 12:59am CDT
7 October = 12:44am CDT
11 October = 12:28am CDT
15 October = 12:12am CDT
19 October = 11:53pm CDT
23 October = 11:37pm CDT
27 October = 11:21pm CDT
31 October = 11:05pm CDT
4 November = 9:50pm CST
8 November = 9:34pm CST
12 November = 9:18pm CST
16 November = 9:02pm CST
20 November = 8:47pm CST
24 November = 8:31pm CST
28 November = 8:15pm CST
2 December = 8:00pm CST
6 December = 7:44pm CST
10 December = 7:28pm CST
14 December = 7:12pm CST

More information:
Burnham's Celestial Handbook, pp. 129-146.
Backyard Astronomer's Guide (third edition) by Dickinson and Dyer, pp. 258-259.
Nightwatch (fourth edition) by Terence Dickinson, pp. 52 and 93-94.
Year-Round Messier Marathon Field Guide by Harvard Pennington, p. 80.
http://messier.seds.org/m/m031.html
http://www.daviddarling.info/encycloped ... omeda.html

26 June APOD from Lorenzo Comolli:
http://apod.nasa.gov/apod/ap130626.html
Last edited by Christopher K. on June 21st, 2014, 12:42 pm, edited 1 time in total.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: M31 (Andromeda Galaxy)

Post by Christopher K. » June 20th, 2014, 8:16 pm

A picture of the Andromeda Galaxy from Joel Tonyan is slide number four in the collaborative gallery from Time Magazine and the Astronomical League. Tonyan made the image in January from Fayetteville, Arkansas.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » August 3rd, 2014, 8:46 pm

High schooler Jacob Bers' image of M31 was chosen by Nemiroff and Bonnell as last Wednesday's APOD. Bers says he's "very humbled" yet there's no denying the pic is a very good one. He took it at a star party; he used a Nikon d5300 on a Vixen scope and Orion mount.

30 July 2014 APOD:
http://apod.nasa.gov/apod/ap140730.html

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » January 10th, 2015, 5:25 pm

An unprecedented view of M31 took its place as Tuesday's APOD. A result of the Panchromatic Hubble Andromeda Treasury, it required over 7900 separate exposures. Although showing only about a third of our neighbor, it resolved a large number of its constituent stars.

6 January APOD:
http://apod.nasa.gov/apod/ap150106.html

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » July 30th, 2015, 5:49 pm

GALEX took eleven different field shots for an ultraviolet view of M31. I was attempting to determine if the blue star had a designation but I couldn't locate one; my guess is it would be a Tycho (TYC) number.

24 July APOD:
http://apod.nasa.gov/apod/ap150724.html

geckgo
Posts: 19
Joined: June 21st, 2015, 2:05 am

Re: Andromeda Galaxy (M31)

Post by geckgo » August 2nd, 2015, 7:06 pm

Breathtaking photos :) Thanks for posting.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » October 11th, 2015, 6:00 pm

I've never searched for M31 from HRPO with a binocular, but recent exercises have increased my familiarity with the Pegasus-Andromeda region of the sky. So I may try this week.

M31 was number six on Jane Houston Jones' countdown list in the "What's Up for October 2015" video.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » October 15th, 2015, 7:08 pm

Last night was my first time from HRPO getting M31 with 10x and I had no trouble. From K-class Mirach to A-class Mu Andromedae, then further along the same distance to the Andromeda Galaxy, and there it was! Or at least there was the central bulge.

This is one of the objects a kid can find with a binoc to qualify for the Astronomical League's Sky Puppy Club.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » January 13th, 2016, 8:48 pm

On 3 December at 7:05pm I looked at M31 with a Bushnell 10x. It forms a fairly easy-to-find right triangle with Nu and 32 Andromedae. I saw some--some--elongation going out from the core.

Christopher K.
Posts: 4763
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Andromeda Galaxy (M31)

Post by Christopher K. » October 10th, 2016, 2:09 pm

Bob King's wonderful article assists in viewing M31 and its sections and companions...
http://www.skyandtelescope.com/astronom ... da-galaxy/

Professor Hynes used the 20OGS to show the public M31 at the Highland Road Park Observatory on 30 September.

Post Reply