Sunflower Galaxy
What is Sunflower Galaxy?
Galaxies· Distance ~27 million ly. Instead of bold arms, short broken spiral fragments tile its disc like the seeds of a sunflower. It is the classic 'flocculent' spiral, and a faint stream of stars — the wreckage of a devoured satellite — loops around it.
📍 Visible from where you are right now — computed in your browser
bearing · altitude · rise time · best time tonight
Where Sunflower Galaxy is in your sky right now: https://nowsky.org/solar/sky?sel=sunflower galaxy — location and time set automatically, no login.
Its place in the sky
A galaxy, in the direction of Canes Venatici, spanning about 12.6 arcminutes of sky — 0.4 times the width of the full Moon.
Distance and scale
| Distance | ~27 million ly |
|---|---|
| Diameter | ~100,000 ly |
| Type | flocculent spiral — short, fragmented arms |
| Constellation | Canes Venatici |
Figures are representative approximations. Source: compiled from NASA and IAU public data.
Discovery and name
Found by Méchain in 1779 — the archetype of a "flocculent" spiral with fleecy, fragmented arms.
Frequently asked
- How far is Sunflower Galaxy from Earth?
- ~27 million ly.
- How big is Sunflower Galaxy?
- ~100,000 ly.
- What kind of object is Sunflower Galaxy?
- flocculent spiral — short, fragmented arms.
- Where in the sky is Sunflower Galaxy?
- In the direction of Canes Venatici.
- Where is Sunflower Galaxy in the sky right now?
- Open the sky view for your location and time and it shows the position in the sky right now.
A flat rotation curve — a specimen for dark matter
The Sunflower Galaxy's disk is tilted at a convenient angle for measuring rotation. Its rotation curve, measured from radio observations of neutral hydrogen, does not fall off with distance from the centre but stays nearly constant — the visible mass of stars and gas alone could not keep the outer stars moving that fast. Such "flat rotation curves", confirmed in many spirals by Vera Rubin in the 1970s, cemented the case for dark matter, and M63 is one of the specimen galaxies.
The hydrogen disk extends far beyond the visible stars and its edge is warped like a dish, read as the trace of a recently swallowed satellite — the same event that left the faint stellar stream wrapping the galaxy in deep images. The short spiral fragments that make the sunflower pattern mean star-forming regions are scattered across the whole disk rather than gathered in grand arms, and why some galaxies grow great arms while others grow fragments remains an open problem.
The galaxy in depth
The Sunflower Galaxy, M63, is a spiral about 27 million light-years away in Canes Venatici. Roughly 100,000 light-years across, it matches the Milky Way in size but not in looks: rather than two or three sweeping arms, dozens of short, broken spiral fragments tile the disc like seeds packed into a sunflower's head — the archetypal 'flocculent' spiral.
Méchain found it in 1779, the first of his discoveries to enter the Messier list. It belongs to the M51 Group along with the Whirlpool, and deep images show a faint loop of stars wrapped far outside the disc — the remains of a dwarf galaxy swallowed billions of years ago. Its fragmented arms arise not from density waves but from local star-forming patches sheared out by rotation, making it a neat contrast with grand-design spirals.
Look between Alkaid at the tip of the Dipper's handle and Cor Caroli in Canes Venatici. Select the Sunflower in the Sky view to mark it; a small telescope shows a bright core inside an oval halo, and large apertures bring out the mottled texture.
Related
Figures are representative approximations. Simulated positions use J2000 mean elements.