Lens size. Since stargazing is a nighttime activity, you’ll need a pair of binoculars that let in plenty of light — so you want to choose binoculars with larger objective lenses. While you could work with 40mm or similarly sized lenses, we’d suggest opting for a pair with 50mm lenses or larger to get the clearest, most detailed images. These are the most powerful binoculars for astronomy, so you’ll give yourself a jaw-dropping viewing experience!
Magnification. The best magnification choice comes down to what you want to see in the sky. If you’d like a big-picture view that allows you to peer at large portions of the sky, a small magnification like 8x might be sufficient. But if you want to get up close to stars and comets that are literally light years away, a greater magnification between 10x and 20x is a better pick. For that reason, you’ll find the most popular binoculars to see stars are these sizes: 10x50, 12x50, 15x50 and even 20x60.