But just a little farther - okay, 500,000 light-years farther - is another spiral galaxy, the third largest in our local group.
Triangulum, also called Messier 33, can be spotted by lucky skywatchers without an assist from a telescope, but it looks like a smudge.
This epic image of the Triangulum Galaxy - also known as Messier 33 or NGC 598 - has a staggering 665 million pixels and showcases the central region of the galaxy and its inner spiral arms. Today, September 9, 2009, NASA released the first images taken with the Hubble Space Telescope since its fix in the spring. 'My first impression on seeing the Hubble images was, wow, that really is a lot of star formation, ' project lead Julianne Dalcanton of the University of Washington said in a statement. It also provides an incredible view of the millions of stars that make up this galaxy. 'The star formation rate intensity is 10 times higher than the area surveyed in the Andromeda galaxy in 2015.' The Triangulum galaxy was chosen for this ultra-high-res photo op because it's positioned such that we can view its structure in great detail.
Astronomers think that Triangulum has avoided disruptive interactions with other galaxies, instead spending the eons tending its well-ordered spiral and turning out new generations of stars.
Another difference between the Triangulum Galaxy and the two more popular spiral galaxies is that the former does not have a bright bulge in its center.
The abundance of gas clouds in the Triangulum Galaxy is precisely what drew astronomers to conduct this detailed survey.
The galaxy contains a huge amount of gas and dust, giving rise to rapid star formation. When stars are born, they use up material in these clouds of gas and dust, leaving less fuel for new stars to emerge.
The Triangulum Galaxy is part of our "Local Group". One of these is the second brightest region of ionized hydrogen found across the entire Local Group-making it ideal for the study of stellar evolution.
As the junior member of this trio, the Triangulum Galaxy provides the valuable comparisons and contrasts that only a close companion can.