Collinder 121 — Open Cluster in Canis Major
Excellent (74/100)
Observe
1Properties
Magnitude
2.6
Angular Size
60 arcmin
Distance
3,500 ly
Open Cluster
Position & Identifiers
Physical size
61 light-years across
— tens of light-years across — wider than the solar neighbourhood
2How easy to spot?
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Easy | Easy | Easy |
| 150 mm Newton 150mm Newt. | Easy | Easy | Easy |
| Celestron C8 (203 mm SCT) C8 203mm | Easy | Easy | Easy |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Easy
on Seestar S50
3Visibility
Set a location in User Settings to see visibility data.
Best season
Nov – Jan
(peak: Dec)
4
Eyepiece View
5
Best Magnification
Discover
6
Light Travel Time Machine
7
Relativistic Travel
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.
NGC 2272
Elliptical galaxy
Galaxy
mag 11.9
4.1°
Canis Major
NGC 2354
Rich open cluster
Open Cluster
mag 6.5
4.1°
Canis Major
M41
NGC 2287
Rich open cluster
Open Cluster
mag 4.5
4.5°
Canis Major
C64
NGC 2362
Rich open cluster
Open Cluster
mag 4.1
5.1°
Canis Major
29 CMa
Eclipsing binary, period 4.4d
Variable Star
mag 4.98
5.1°
Canis Major
NGC 2367
Open cluster
Open Cluster
mag 7.9
6.1°
Canis Major
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