M100
spiral galaxy · Coma Berenices · 9.4ᵐ
A Messier catalogue object — spiral galaxy in Coma Berenices.
Notable facts
About 1/4 the apparent diameter of the Moon.
In brief
Which constellation is M100 in?
M100 lies in Coma Berenices.
Is M100 visible to the naked eye?
9.4ᵐ — a telescope is needed.
When is the best time to observe M100?
Best observed in March.
Data
- RA / Dec (J2000)
- 12h 23m · +15° 49′
- Type
- spiral galaxy
- Constellation
- Coma Berenices
- How to observe
- 9.4ᵐ — a telescope is needed
- Angular size
- 7×6′
- Designation
- M100 · NGC 4321
Observing tip
Get away from city light pollution — it washes out the faint glow of galaxies first.
Altitude above the horizon by latitude
| Latitude | Maximum altitude | Rise azimuth |
|---|---|---|
| +60° | 46° | 57° |
| +55° | 51° | 62° |
| +45° | 61° | 67° |
| +30° | 76° | 72° |
| 0° | 74° | 74° |
| −35° | 39° | 71° |
Geometric altitude at upper culmination, atmospheric refraction not included. Positive latitudes are in the northern hemisphere.
Culmination time by month
| Month | Culmination |
|---|---|
| January | 04:37 |
| February | 02:30 |
| March | 00:45 |
| April | 22:51 |
| May | 20:57 |
| June | 18:51 |
| July | 16:47 |
| August | 14:46 |
| September | 12:53 |
| October | 11:04 |
| November | 09:04 |
| December | 06:55 |
Upper culmination in local solar time — no time-zone or daylight-saving correction applied.