Galaxy-building theory says there are stars and there are stage hands. The bright, shining galaxies filled with stars, the theory goes, took star-building gas from somewhere else, but we couldn't find exactly where the help came from. Now astronomers have likely found that source; starless "dark galaxies" that fed others early in the history of the universe have been seen.
The European Southern Observatory's Very Large Telescope was able to catch a glimpse of the galaxies for the first time as they were being illuminated by a quasar. Since the galaxies are bad at forming stars on their own, they're difficult to see without a light source like a quasar, which shines UV light and can cause a fluorescent glow in the starless galaxies. Their existence has been hinted at before, but this marks the first direct look.
Some estimations were also offered by researchers on the properties of these galaxies. The mass of their gas is about 1 billion times that of the Sun's, and they're about 100 times less conducive to star-forming than similar neighbors.
The find also validates progressive rock band King Crimson's early scientific predictions.
Another nail in the coffin of dark matter.
Dark matter is used to explain interactions within a galaxy. What bearing would dark galaxies have on dark matter?
Wait, I thought dark matter was the stuff that collects under the rim of a toilet bowl. I'm so confused. How did NASA's $20,000 toilet get all the way out there?
Agreed, Democedes, this has nothing to do with Dark Matter, but to say, "dark matter is used to explain interactions within a galaxy," while technically correct, is a somewhat shallow explanation. The most defining features of dark matter are that it accounts for the vast majority of mass in the universe, though we only interact with it through gravity, and that it's gravitational pull seems to dictate where visible matter coalesces into galaxies.
It would be interesting to know the ratio of dark galaxies to visible ones, and if any are heading for the Milkyway.
Such a terrible thought. Whole galaxies, unimaginable spans of space, filled with frozen planets and nebulae. All existing in absolute pitch darkness for eternity. Nothing but the stars around them. What kind of life or organized structures might evolve in environments like that?