The Triangulum Galaxy, writ large

By Phil Plait | July 11, 2011 7:17 am

Need a little face-on spiral awesomeness for your Monday morning? Then try this magnificent image of the nearby face-on spiral galaxy M33, aka the Triangulum Galaxy:

[Click to islanduniversalize, or go here to get the cosmic 7900 x 8000 pixel version.]

That not enough for ya? Then try this: Here’s a zoomable and pannable version!

You’re welcome.

This image is from Davide de Martin, who takes images from professional observatories, reprocesses them, and puts them on his Sky Factory website. M33 is a bit of an odd beast: it’s the second-closest spiral galaxy to our own — at about 3 million years away, it’s just a bit farther away than the Andromeda Galaxy — but it’s fainter than you might expect in the sky. That’s because it’s dinky, less than half the size of our Milky Way, and face-on, which means that small amount of light gets spread out, dimming it.

I’ve never seen it naked eye (Andromeda is actually pretty easy to spot from a dark site) but I’ve observed it many times with binoculars and a small telescope. Davide had a bit of an advantage though: this picture is from observations using the 4-meter Mayall telescope at Kitt Peak, a fine instrument indeed. The picture uses mostly "natural" color, adding together blue, green, and red-filtered images.

Also included in that summation is one more image using a filter that only lets though a very specific wavelength of light associated with warm hydrogen. Called Hα, this is given off by gas clouds forming stars, and is shown here as the sharp red color. So wherever you see those blobs of red, stars are forming at a furious rate. And look to the upper left: see that particularly large and bright nebula? That is NGC 604, a monstrous star-forming region that’s 1500 light years across or more; it puts our own Orion Nebula to shame. It’s one of the largest stellar factories in the Local Group of galaxies; if it were as close as Orion it would be visible in the daytime!

One other thing: the spiral arm to the left and below NGC 604 appears to be sharply defined and almost straight. I’m thinking that’s a perspective effect, but the arm itself does appear pretty well-defined in a far-infrared image as well. It’s interesting what you find looking at such fine images, and comparing them at different wavelengths.

I had a lot of fun flying over the zoomable image. The red star-forming nebulae come in many shapes and sizes; take a look all the way over on the right for a couple of them that have filaments and arcs; I think the stars inside them are blowing away the gas, sculpting it into eerie and lovely shapes.

There’s a lot to see here. Have fun!

Image credit: KPNO, NOAO, AURA, Dr. Philip Massey (Lowell Obs.) – Image processing: Davide De Martin.


Related posts:

- Awesome Antennae
- A Swiftly UV galaxy
- A WISE view of a small neighbor
- Sky Factory’s stellar foreground
- M83′s nursing arms

CATEGORIZED UNDER: Astronomy, Pretty pictures

Comments (17)

  1. Messier Tidy Upper

    Need a little face-on spiral awesomeness for your Monday morning?

    Yes please – and thankyou. :-)

  2. Messier Tidy Upper

    To think the magnificent splendour of the Triangulum (or alternatively Pinwheel – but that gets it confused with Messier 101) galaxy could have come from this :

    http://www.youtube.com/watch?v=6eZm3LHlyrs

    Titanic galactic collision. :-o :-)

    Messier 33′s wiki-basics here :

    http://en.wikipedia.org/wiki/Messier_33

    Plus photographic finderchart here :

    http://stars.astro.illinois.edu/sow/tri-t.html

    via Kaler’s ‘Stars’ website – in case folks wish to know more and hopefully will find these interesting &/or useful. :-)

  3. Messier Tidy Upper

    M33 is a bit of an odd beast: it’s the second-closest spiral galaxy to our own — at about 3 million years away, it’s just a bit farther away than the Andromeda Galaxy

    Well, there is the Large Magellanic Cloud’s having a spiral structure of sorts too! Yeah, okay, its generally classed as an iregular galaxy instead but I’d say a barred spiral (albiet small and somewhat distorted) classification fits its shape better! ;-)

    [/Ultra-fussy nitpick that I couldn't resist noting.]

  4. Kevin

    Totally off topic (not good for someone who comments here about once a year) but, for the record, today Neptune completes its first orbit since it was discovered in 1846.

  5. Nice Image – and nice use of the technical astronomical term “dinky”

  6. Potco

    There are a few particularly bright stars, like the one on the top border about a third of the way across, are these supernova or just a star closer to the telescope?

  7. Scott P.

    “That’s because it’s dinky, less than half the size of our Milky Way, ”

    I remember when it was thought that it was just about the same size as the Milky Way. But now that we know the Milky Way is bigger than previously thought, that makes M33 “dinky”? Isn’t that rather chauvinistic?

  8. Zippy the Pinhead

    Kevin @4: Happy (1st?!) birthday, Neptune! We are all newborns in Neptune years!

  9. Pete Jackson

    @6 Potco: A supernova might occur only every 100 years or so in M33, so we’re not likely to have any in this image, or we would have already heard about it! The isolated bright stars are foreground stars in our own Milky Way galaxy. The bright stars near NGC 604 give an idea of how bright the supergiants belonging to M33 are in this image.

    Fantastic image, Phil. You’re sure great at digging these up.

  10. Three million years away… so is it coming at us? Or are those light years? :D

  11. DrFlimmer

    That is NGC 604, a monstrous star-forming region that’s 1500 light years across or more; it puts our own Orion Nebula to shame. It’s one of the largest stellar factories in the Local Group of galaxies; if it were as close as Orion it would be visible in the daytime!

    If one would compare it to the Tarantula Nebula in the Large Magellanic Cloud, which one would win? The Tarantula has many very massive stars and is also extremely furious.

  12. I’ve seen M33 naked eye exactly twice, both times were on nights when I had trouble finding my way around the sky because there were too MANY stars. You know it’s a great night when…

  13. Anchor

    It’s without question a magnificent image.

    if only the interior bright portions of the HII regions weren’t maxed out I’d like it even better.

  14. Wes

    What is the galaxy in the bottom left corner?

  15. Anchor

    Bipedal Tetrapod : …EXACTLY!

  16. bassmanpete

    At about the midline just in from the right edge is an area with some bright blue stars surrounded by an irregular red border. Is this the expanding cloud from a fairly recent supernova? There are several other similar areas but this was the most prominent to my eyes.

    It’s images like this that make one realise just how incredibly brief our lives are. It would be nice to be able to say to some youngster “Well I remember when the Large Magellanic Cloud was captured by the Milky Way and I’m looking forward to us merging with Andromeda!”

  17. Kris Mrowwy

    The resolution is actually – or at least now – 3950 × 3984. I swear I’m not complaining…

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

ADVERTISEMENT

See More

ADVERTISEMENT
Collapse bottom bar
+

Login to your Account

X
E-mail address:
Password:
Remember me
Forgot your password?
No problem. Click here to have it e-mailed to you.

Not Registered Yet?

Register now for FREE. Registration only takes a few minutes to complete. Register now »