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Caldwell 5 (IC 342) & Pinwheel Galaxy (NGC 5457)
Lauren Zuiderveen & Macy Schimmel

IC 342 NGC 5457
Caldwell 5 - Lauren Zuiderveen Pinwheel Galaxy- Macy Schimmel

Clouds of dust aren't always swept up; sometimes they are studied through a telescope. Both Caldwell 5 and the Pinwheel Galaxy are galaxies, specifically spiral galaxies. A spiral galaxy is a cluster of stars, dust, and gasses in a whorled shape. There are two different types of spiral galaxies: barred and unbarred. Caldwell 5 and the Pinwheel Galaxy are both unbarred because they don't have a line running through the middle of them, which would make their shape slightly elongated.

Caldwell 5, otherwise known as IC 342, was discovered by William Frederick Denning in 1895.This galaxy is located in the constellation known as Camelopardalis. Different stars, gasses, and dust within the Galactic Equator block the view of IC 342, making it rather faint and unclear. It is located in a group, called IC 342/Maffei Group, that is relatively near the Local Group where the Milky Way Galaxy is located. An important characteristic of Caldwell 5 is the thousands and millions of red and yellow stars. Because thses coller stars are able to last longer than hot, blue ones, this means that this galaxy is relatively old.

The Pinwheel Galaxy (NGC 5457) is about 21 million light years away from Earth in the Ursa Major constellation. Pierre Mechain discovered this galaxy on March 27, 1781. The average diameter is 170,000 light years which is about the same size as our Milky Way Galaxy. Its shape is very pinwheel-like, but it is lopsided due to gravitational interactions with other nearby galaxies.The small central bulge, or highly dense middle of the galaxy, is about 3 million solar masses (mass of the sun). The rotating ring of stars around the bulge, or disk, is 100 billion solar masses. In the Pinwheel Galaxy, there are high amounts of H II regions (atomic Hydrogen that is ionized), making it really easy for stars to form in this galaxy. Because forming stars is easy for the Pinwheel Galaxy, there are lots of new, hot, blue stars, making it stand out from other galaxies.

As seen by the pictures, both of the galaxies are spiral galaxies, meaning they are both made from different gasses and dusts and are shaped in a spiral, pinwheel-like pattern. Another similarity is that they have H II regions, Caldwell 5's being a nucleus. Both can easily form stars, but Caldwell 5 has slowed down star production. These two galaxies are also lopsided, a result of their close proximities to other galaxies and their gravitational pulls.

Caldwell 5 appears to have many more red and yellow stars which would then signify that it is an older galaxy and is not producing as many new stars as the Pinwheel Galaxy. The Pinwheel Galaxy has more blue and purple stars siginigfying that it is younger and still producing new stars. The Pinwheel Galaxy is also more defined in appearence, being easier to see in the night sky than Caldwell 5, which might contribute to why it was discovered sooner than Caldwell 5.


Buta, Robert J., and Marshall L. McCall. "The IC342/Maffei Group Revealed." Astrophysical Journal Supplement Series, vol. 124, no. 33-93, 1999. Accessed 24 Nov. 2016. <>.

"IC 342." Wikipedia.16 Nov. 2016, <>. Accessed 21 Nov. 2016.

Nemiroff, Robert, and Jerry Bonnell. "Hidden Galaxy IC 342.", edited by Robert Nemiroff and Jerry Bonnell, NASA, 29 Jan. 2016, <>. Accessed 21 Nov. 2016.

"Pinwheel Galxy." Wikipedia31 Oct. 2016, <>. Accessed 21 Nov. 2016.

Redd, Nola T. "Spiral Galaxy Facts & Definition." Space.com15 Aug. 2013, <>. Accessed 21 Nov. 2016.


Object Caldwell 5 Pinwheel Galaxy
Right Ascension (J2000) 03:46:48 14:03:12
Declination (J2000) +68:05:44 +54:20:58
Filters used B (Blue), C (Clear), R (Red), V (Green) B (Blue), C (Clear), R (Red), V (Green)
Exposure time per filter B(300s), V(150s), and R (150s); C (150s) B(300s), V(300s), and R (250s); C (250s)
Image dimension 1012x482 pixels; 21.9x10.4 arcminutes 691x512 pixels; 15.0x11.1 arcminutes
Date/time observed October 8, 2016, 7:39 UT October 7, 2016, 3:20 UT



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