Space

Speeding star offers a rare glimpse of the Milky Way's galactic centre

A star has been spotted shooting away from the heart of our galaxy at around 500 kilometres per second, giving astronomers clues about a group of stellar objects that are hard to observe directly

By Alex Wilkins

7 March 2025

A map of the sky assembled using data from the Gaia space telescope, with the centre of the Milky Way in the middle of the image
ESA/Gaia/DPAC

Astronomers have had a rare glimpse into the heart of the Milky Way thanks to an errant star expelled from the galactic centre.

At the middle of our galaxy is a supermassive black hole, closely surrounded by a group of hundreds of stars. Slightly further out is a larger disc of stars, and further out still is an even larger star group, called the nuclear star cluster (NSC).

Astronomers have…

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