This luminous Hubble space telescope image shows a small galaxy called the Sagittarius dwarf irregular galaxy (SagDIG for short).

Hubble's sharp vision reveals thousands of individual stars inside the galaxy, located 3.5 million light-years away.

Unlike spiral or elliptical galaxies, dwarf irregular galaxies like this one have a much smaller physical size and no particular structure.

Image description:

Thousands of small, blue stars dot the image and are more tightly concentrated near the centre. Closer stars in the foreground shine in yellow, white and orange hues, with diffraction spikes.