Pinwheel Galaxy
Overview
Spiral galaxy
A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as...
distanced 21 million light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s (six megaparsecs) away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Ursa Major
Ursa Major
Ursa Major , also known as the Great Bear, is a constellation visible throughout the year in most of the northern hemisphere. It can best be seen in April...
, first discovered by Pierre Méchain
Pierre Méchain
Pierre François André Méchain was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep sky objects and comets.-Life:...
on March 27, 1781, and communicated to Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
who verified its position for inclusion in the Messier Catalogue as one of its final entries.
On February 28, 2006, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
and the ESA released a very detailed image of Pinwheel Galaxy, which was the largest and most detailed image of a galaxy by Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...
at the time.
Unanswered Questions
