The Hubble Space Telescope has snapped an incredible image of the Triangulum Galaxy, which is 3 million light years from our own Milky Way Galaxy. The Vast spiral galaxy is located just three million light-years from Earth, and can sometimes even be seen by the naked eye as a faint, nebulous object on a clear night.
It's our neighbor in a collection of dozens of galaxies called the Local Group, and was captured in unprecedented detail in image consisting of 54 Hubble fields of view stitched together, revealing almost 25 million individually resolved stars.
This image of the Triangulum Galaxy is a composite of about 54 different pointings with Hubble's Advanced Camera for Surveys.
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. These numbers are hard to grasp when already in this image 10 to 15 million individual stars are visible. Some 1500 light-years across, this is one of the largest, brightest concentrations of ionized hydrogen (H II) in our Local Group of galaxies, and it is a major center of star formation. By comparison, the Andromeda Galaxy is 200,000 light-years across and the Milky Way is 100,000 light-years in diameter.
Whilst both are spiral galaxies, Messier 33 differs from the Milky Way in many ways.
In contrast to the two larger spiral galaxies, Triangulum does not have a bright bulge at its centre - and it also lacks a bar connecting its spiral arms to the centre. It does, however, contain a huge amount of gas and dust, giving rise to rapid star formation.
ESA says the Triangulum image is the second-largest ever released by Hubble and will help astronomers better understand how stars form and evolve.
Usually when astronomers talk about our neighbouring galaxy, they're talking about Andromeda, which is a cozy 2.5 million light-years away. Striking areas of star birth glow bright blue throughout the galaxy, particularly in handsome nebulas of hot, ionized hydrogen gas like star-forming region NGC 604 in the upper left.