Astronomers have discovered two new dwarf galaxies in the Milky Way's immediate neighbourhood. The dim clusters are both around 640,000 light years from our Sun, Reuters reports.

One of the new boys is located in the constellation Canes Venatici. The other, found in Bootes is the least luminous galaxy yet discovered. In universal terms it's a mere tealight, with a brightness of about 100,000 Suns.

Measurements of metal abundances detected the pair. They are too dim to be revealed by Earthbound photography.

The dim duo bring the total number of dwarves around the Milky Way to 14, though theory predicts there should be hundreds embedded in dark matter clumps. The discrepancy between observations and calculations is yet to be resolved.

The finding comes from the Sloan Digital Sky Survey, which aims to systematically map a quarter of the universe in unprecedented detail. ®