Caldwell 21 — Galaxy in Canes Venatici
NGC 4449
About C21
Description
NGC 4449 is an irregular dwarf galaxy in Canes Venatici, about 12 million light-years away. It is undergoing a galaxy-wide starburst, producing new stars at a prodigious rate throughout its entire body rather than just in a central region.
Observing Tips
Visible as a small, rectangular glow in a 4-inch telescope. Higher magnification reveals a mottled texture from the numerous HII regions. Best observed in spring evenings when Canes Venatici is high.
History
Discovered by William Herschel on April 27, 1788. It is considered a Magellanic-type irregular galaxy similar in many ways to the Large Magellanic Cloud.
Fun Facts
NGC 4449 is one of the best-studied starburst dwarf galaxies. It is currently consuming a smaller companion galaxy, making it one of the few cases where dwarf galaxy cannibalism has been directly observed.
Observe
1Properties
Position & Identifiers
2How easy to spot?
| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Medium+ | Medium+ | Medium |
| 150 mm Newton 150mm Newt. | Easy | Easy | Easy |
| Celestron C8 (203 mm SCT) C8 203mm | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
3Visibility
Set a location in User Settings to see visibility data.
4
Eyepiece View
5
Best Magnification
Explore
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Surface Brightness
7
Morphology Decoder
8
Inclination & True Shape
9
Redshift
10
Size Comparator
Discover
11
Light Travel Time Machine
12
Relativistic Travel
Community Photos (1)
Credit: NASA, ESA, A. Aloisi (STScI/ESA), and The Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration. License: Public domain. (Wikimedia Commons)
Skybred Mar 2, 2026
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
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