An arc of stars stretches across the night sky, twisted by gravitational effects caused by the Milky Way galaxy.

Originating from a cluster of some 50,000 stars, dubbed NGC 5466, the stellar arc stretches across a 45-degree swatch of the night sky.

For comparison, the Moon is about one-half a degree. Your fist – measured from thumb to pinky – covers about 10 degrees.

Researchers at the California Institute of Technology’s (Caltech) Spitzer Science Center backtracked star positions to NGC 5466 to find the previously unseen arc. The research is detailed in the March issue of the journal Astrophysical Journal Letters.

NGC 5466 and its star stream sit about 76,000 light-years from Earth and rise upwards from the bright star Arcturus in the constellation Bootes. The stream arcs over the Milky Way galaxy, which slowly ripped stars into the formation around NGC 5466 through a gravitationally-dependent process known as tidal stripping.

The stream of stars was not previously detected because its pattern was drowned out by the light of the Milky Way, researchers said. The arc begins just south of the Big Dipper and continues downward across the sky towards the Arcturus position, they added.

-- SPACE.com Staff

Credit: Caltech/Spitzer Science Center.