M63 - SUNFLOWER GALAXY

The Sunflower Galaxy (M63, NGC 5055) is a spiral galaxy located approximately 29 million light-years from Earth in the constellation Canes Venatici. It was discovered by Pierre Mechain in 1779, and Charles Messier added it to his catalog shortly afterward. M63 is classified as a flocculent spiral galaxy, meaning that instead of having two or three well-defined grand-design spiral arms, its disk is covered with many short, discontinuous arm segments that create a patchy, multi-armed spiral pattern resembling the petals of a sunflower, hence its common name. The galaxy spans about 98,000 light-years in diameter and is a member of the M51 Group of galaxies, which also includes the Whirlpool Galaxy. M63 has a bright, yellowish central bulge surrounded by a disk mottled with dust lanes, blue star-forming regions, and pinkish HII regions. Deep imaging has revealed a faint, enormous tidal stream looping around the galaxy, extending far beyond the visible disk. This stream is the remnant of a smaller satellite galaxy that was tidally disrupted and absorbed by M63, providing direct evidence of the hierarchical galaxy growth process. The galaxy also possesses an extended outer disk of hydrogen gas detectable in radio wavelengths that extends well beyond the optical disk and shows a pronounced warp. In amateur telescopes, M63 appears as an elongated patch of light with a bright nucleus. A 6-inch telescope under dark skies can begin to show mottled structure in the disk, while 10-inch and larger instruments reveal the patchy spiral pattern that gives the galaxy its distinctive character.

M63 spans approximately 98,000 light-years in diameter and lies about 29 million light-years from Earth as a member of the M51 Group.