A bright streak of stars containing a clump of glowing pinkish gas at its right end, surrounded by many more distant galaxies.

An intriguing young-looking dwarf galaxy

The bright streak of glowing gas and stars in this NASA/ESA Hubble Space Telescope image is known as PGC 51017, or SBSG 1415+437. It is a type of galaxy known as a blue compact dwarf. This particular dwarf is well studied and has an interesting star formation history. Astronomers initially thought that SBS 1415+437 was a very young galaxy currently undergoing its very first burst of star formation, but more recent studies have suggested that the galaxy is in fact a little older, containing stars over 1.3 billion years old.

Credits: ESA/Hubble and NASA Acknowledgement: Alessandra Aloisi (STScI) and Nick Rose