Here is the transcript for my podcast about how to see the Andromeda Galaxy (M31), the double star Gamma Andromedae, and the Deer Lick Group during the next few days.
Check out the Astronomy.com's interactive star chart to see an accurate map of your sky. It'll help you locate some of this week's key targets. Astronomy magazine subscribers have access to a slew of cool functions with StarDome PLUS.
--Start transcript--
The Andromeda Galaxy, the double star Gamma Andromedae, and the Deer Lick Group are visible in the next few days. We’ll help you find them in this week’s Astronomy magazine podcast.
Hello, I’m Astronomy magazine senior editor Michael Bakich. Each week, I highlight three different night-sky targets for you to see:
One object you can find without optical aid
One object to find with a small telescope
One deep-sky object to find with an 8-inch or larger telescope for you avid astronomers.
Autumn’s finest galaxy
Last week, in my chat about the Great Square of Pegasus, I mentioned an object you can find by using the baseball diamond in the sky: the Andromeda Galaxy (M31).
To see this object with your naked eyes, you’ll need to observe from a dark site away from city lights. Don’t get me wrong — the Andromeda Galaxy is bright. It’s just that, because of its size, all that light spreads out over a pretty large area.
Most observers know M31 is pretty big. But did you know that six Full Moons could fit side-by-side in front of it? And you’d need a row of another six Moons to cover it. That’s right, the Andromeda Galaxy measures a full 3° long and more than 1° wide.
With binoculars, you can slightly upscale your approach to observing M31. They’ll give you a nice overall view. Through 10x to 20x binoculars, you’ll spot M31’s nucleus, its dust lanes, and two of its companion galaxies, M32 and NGC 205. Once you’ve found all this, try to trace the full 3°-extent of the Andromeda Galaxy through your binoculars.
A twin treat
This week, I wasn’t sure if I wanted to put Gamma (γ) Andromedae in the small-scope category or present it as the large-scope challenge object. I’ll explain below.
Gamma And is the 3rd-brightest star in the constellation, shining at 2nd magnitude. But its visual output actually combines the light from a colorful pair of stars: yellowish Gamma1 (γ1) Andromedae shines at magnitude 2.3, and bluish Gamma2 (γ2) glows at magnitude 3.6. About 10" separate the two components, so any telescope will easily split this pair.
Why, then, did I consider using it as a challenge object? The reason is that Gamma2 is also a double, but one with a separation of only 0.4". Gamma2’s components are just about the same brightness, at magnitudes 4.84 and 4.87. I split this star with a perfectly aligned and totally cooled-down 11-inch Schmidt-Cassegrain telescope in 2001. You won’t split it with much less aperture.
What’s in a name?
Deep-sky objects have some fanciful names. Usually, however, they fit the view. For example, the Blue Snowball (NGC 7662) is blue and round, the Omega Nebula (M17) looks like that Greek letter, and Gomez’s Hamburger (IRAS 18059–3211) looks like a sandwich.
But what’s with a deep-sky object called the “Deer Lick Group”? Well, about 20 years ago, American amateur astronomer Tom Lorenzin bestowed the common name on this galaxy group to honor the Deer Lick Gap, which lies in the mountains of North Carolina. Apparently, Tom had a memorable view of these galaxies from there.
The Deer Lick Group’s brightest member is NGC 7331. From a dark sky, you can spot this magnitude 9.5 galaxy through binoculars, but a telescope brings out a lot more detail. Through a 10-inch scope with a low-power eyepiece, you’ll see three galaxies to NGC 7331’s east that form an equilateral triangle. These galaxies are not NGC 7331’s companions but lie much farther away.
At 200x, the galaxy shows a bright nucleus surrounded by a nebulous glow 3 times as long as it is wide. Larger scopes show the western edge ends abruptly at a dust lane. On nights of good seeing, look for a spiral arm shining beyond this lane.
--End transcript--
Last week's podcast: Great Square of Pegasus, globular cluster M15, and Stephan’s Quintet
Last week's transcript
Astronomy podcasts