Galaxy in Canes Venatici
Sunflower Galaxy (M63)
The Sunflower, and a flocculent spiral — not two clean arms but dozens of short patchy ones, which is exactly the texture the name is reaching for. A faint stream of stars loops around it, the remains of something it ate.
Flocculent spirals are the more common kind and the less photogenic, and what causes the difference is still open: grand designs like M51 seem to need a companion or a bar to drive a clean wave, while galaxies left alone produce this — dozens of short arms forming and dissolving independently, more like weather than structure.
- Catalogue
- M63
- Type
- Galaxy
- Constellation
- Canes Venatici
- Distance
- 27 million light-years
- Apparent magnitude
- 8.6
- Surface brightness
- 21.7 mag/□″
- Apparent size
- 10′ × 6′
- Right ascension
- 13h 16m
- Declination
- +42.03°
- Found by
- Pierre Méchain, 1779
Small enough that its 8.6 magnitudes arrive concentrated rather than smeared: 21.7 per square arcsecond, which is why it stands out from the sky better than its brightness alone suggests. Why surface brightness is the number that matters.
Could you see it?
Straightforward with 10×50 binoculars from Bortle 5.
| Sky | Eye | 10×50 | 80mm | 130mm | 200mm |
|---|---|---|---|---|---|
| Bortle 1 21.9 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 2 21.7 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 3 21.4 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 4 20.9 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 5 20.3 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 6 19.3 mag/□″ | No | Challenge | Challenge | Challenge | Challenge |
| Bortle 7 18.6 mag/□″ | No | No | No | No | No |
| Bortle 8 18.1 mag/□″ | No | No | No | No | No |
| Bortle 9 17.8 mag/□″ | No | No | No | No | No |
At the eyepiece
A bright, elongated glow with a core that stands out sharply, and no arms to speak of at the eyepiece — flocculent structure does not survive visual observation. 200mm from a dark sky gives a mottled texture across the face, which is as close as you will get to what the photographs show.
When, and from where
Highest in the middle of the night in April. Well placed for the northern hemisphere and overhead for anyone near 42°N. South of 48°S it stays below the horizon.
| Latitude | Highest it gets | |
|---|---|---|
| 60°N Oslo, Anchorage | 72° | Never sets |
| 51°N London, Calgary | 81° | Never sets |
| 40°N New York, Madrid | 88° | |
| 30°N Cairo, Houston | 78° | |
| 0°N the equator | 48° | |
| 33°S Sydney, Cape Town | 15° | Low — in the murk |
Nearby in the sky
The whole catalogue →One more of the catalogue sits within five degrees, close enough to take in on the same night without moving far. Everything below is measured from M63 itself, not from the middle of Canes Venatici.
- M94 Cat's Eye Galaxy 4.7° apart Canes Venatici · magnitude 8.2 · binoculars from Bortle 5 or darker
- M51 Whirlpool Galaxy 5.7° apart Canes Venatici · magnitude 8.4 · binoculars from Bortle 5 or darker
- M106 Galaxy 11° apart Canes Venatici · magnitude 8.4 · binoculars from Bortle 4 or darker
- M101 Pinwheel Galaxy 15° apart Ursa Major · magnitude 7.9 · needs more than binoculars
One of 110. Positions J2000; the sky is the final authority.