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A new type of galaxy, so compact that some have previously been misclassified as stars, has been discovered by astronomers led by Michael Gregg of °ÄÃÅÁùºÏ²Êͼ¿â and the Lawrence Livermore National Laboratory and Michael Drinkwater of the University of Queensland, Australia.

A galaxy like our own Milky Way is about 100,000 light years across and contains a hundred billion stars. The newly recognized galaxies squeeze their stars into a region only 1/500 the diameter of the Milky Way.

The researchers found the "ultra-compact dwarf galaxies" in the Fornax galaxy cluster, 60 million light years distant from Earth.

The team used the Anglo-Australian Telescope (AAT) at Coonabarabran, Australia, to conduct the initial survey and identify seven ultra-compact dwarf galaxies among 2,500 other objects in the Fornax cluster. They used the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope in Chile and the °ÄÃÅÁùºÏ²Êͼ¿â's Keck Telescope in Hawaii to measure the size of the galaxies and how fast stars are moving within them.

Ultra-compact dwarf galaxies could be the remains of larger objects that have been whittled away over eons by encounters with giant galaxies in the same cluster.

Other team members include: Michael Hilker of Bonn University, Germany; Kenji Bekki and Warrick Couch of the University of New South Wales, Australia; Harry Ferguson of the Space Telescope Science Institute in Baltimore, Md.; Bryn Jones of the University of Nottingham, England; and Steven Philipps of the University of Bristol, England. The finding was reported in the May 29 edition of Nature.