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Ursa Major

Ursa Major, Latin for 'Great Bear,' is a prominent constellation in the northern sky. It is the third-largest constellation and contains the Big Dipper asterism, which is often used as a navigational aid due to its proximity to Polaris, the North Star.

Source: science.nasa.gov

APODs including "Ursa Major"

NGC 2685: The Helix Galaxy

14/07/2025

NGC 2685: The Helix Galaxy
Image Credit: Stefan Thrun / NASA APOD

What is going on with this galaxy? NGC 2685 is a confirmed polar ring galaxy - a rare type of galaxy with stars, gas and dust orbiting in rings perpendicular to the plane of a flat galactic disk. The bizarre configuration could be caused by the chance capture of material from another galaxy by a disk galaxy, with the captured debris strung out in a rotating ring. Still, observed properties of NGC 2685 suggest that the rotating helix structure is remarkably old and stable. In this sharp view of the peculiar system also known as Arp 336 or the Helix galaxy, the strange, perpendicular rings are easy to trace as they pass in front of the galactic disk, along with other disturbed outer structures. NGC 2685 is about 50,000 light-years across and 40 million light-years away in the constellation of the Great Bear (Ursa Major). Piece it All Together: Astronomy Puzzle of the Day