Usually, when astronomers talk about our neighboring galaxy, they are talking about Andromeda, which is a cozy 2.5 million light-years away. But just a little more – OK, 500,000 light years farther away – is another spiral galaxy, the third largest of our local group. Hubble has just released its more detailed view of the galaxy, which is known as Triangulum (can you see why?).
The full image contains almost 25 million stars and will help scientists study not only the Triangular Galaxy, but also Andromeda and ours.
Below is the full image, and you can find even higher resolution images here.
The image consists of 54 fields of view of Hubble, from February 2017 to February 2018, according to a statement from the Space Telescope Science Institute. The jagged edges are an artifact of how Hubble cameras are organized, as we explained in this April 2018 blog.
Astronomers have measured the Triangulum about 60,000 light-years across and contain about 40 billion stars – by comparison, the Milky Way spans about 150,000 light-years and has hundreds of billions of stars. But it is undergoing extreme star formation, perhaps 10 times more intense than Andromeda, according to the statement.
"My first impression of seeing the Hubble images was, wow, that there really is a lot of star formation," said astronomer Julianne Dalcanton of the University of Washington in Seattle, according to the press release.
Hubble shoots images at an incredibly high resolution, of course, but it's not the only telescope that can see this galaxy. The Triangulum is one of the most distant objects that can be seen with the naked eye in dark skies – it is in the constellation Triangulum, near Andromeda. Astronomer Steven Bellavia, an engineer at Brookhaven National Laboratory, coincidentally sent me an image he took of the galaxy with a 71mm refracting telescope and a 20-megapixel astronomical camera over two hours. He captured the view of the North Fork of Long Island (accessible from New York by train) two weeks ago.
As always, this is your reminder to see space! It's pretty cool.