500 000 light-years from Earth, Leo IV is one of more than a dozen ultra-faint dwarf galaxies found lurking around our Milky Way galaxy.
Image credits: NASA, ESA, and T. Brown (STScI)
Astronomers have used the NASA/ESA Hubble Space Telescope to study some of the smallest and faintest galaxies in our cosmic neighbourhood. These galaxies are fossils of the early Universe: they have barely changed for 13 billion years. The discovery could help explain the so-called “missing satellite” problem, where only a handful of satellite galaxies have been found around the Milky Way, against the thousands that are predicted by theories. (read more)