M101 - The Pinwheel Galaxy
Credits: Keith Turnecliff, Long Itchington
M101, also known as the Pinwheel Galaxy, is a giant spiral disk of stars, dust and gas is 170,000 light-years across — nearly twice the diameter of our galaxy, the Milky Way.
M101 is estimated to contain at least one trillion stars. The galaxy’s spiral arms are sprinkled with large regions of star-forming nebulas.
These nebulas are areas of intense star formation within giant molecular hydrogen clouds. Brilliant, young clusters of hot, blue, newborn stars trace out the spiral arms.
Located 25 million light-years away from Earth in the constellation Ursa Major, M101 has an apparent magnitude of 7.9.
Facts about M101 by Keith Turnecliff
The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) is a face-on spiral galaxy.
Discovered by Pierre Méchain on March 27, 1781, it was communicated to Charles Messier who verified its position for inclusion in the Messier Catalogue as one of its final entries.
It can be spotted through a small telescope and is most easily observed during April onwards.