Fluffiest galaxies discovered

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The adorably-named Dragonfly 44 is 70,000 light years across—about twice that of the Milky Way—and one of the most diffuse galaxies yet observed.

"If the Milky Way is a sea of stars, then these newly discovered galaxies are like wisps of clouds", said van Dokkum. "We are beginning to form some ideas about how they were born and it's remarkable they have survived at all. They are found in a dense, violent region of space filled with dark matter and galaxies whizzing around, so we think they must be cloaked in their own invisible dark matter 'shields' that are protecting them from this intergalactic assault."

The fluffy galaxies, captured by Keck Observatory, are about 300 million light years away and something of a cosmic mystery.