It looks like we might have overestimated how many neighbors we have. New predictions show that the universe might be an emptier place than we imagined.
Since the Hubble launched, we’ve been seeing stunning image of the crowded universe. Most of the images come accompanied by assurances that what we see in the images is just the start. Astronomers have been excitedly guessing at the amount of faint, distant galaxies that they can’t see. Lurkers surely outnumbered visible galaxies.
New simulations done on Blue Waters, a supercomputer at the National Center for Supercomputing Applications indicate that that isn’t the case. Researchers at Michigan State University simulated the formation of the early universe. The number of bright, luminous galaxies that the simulations predicted just about synced up with the data we can see from the Hubble. But the simulations indicated that number of faint galaxies, which the Hubble can’t see, wasn’t anywhere near what previous predictions had estimated. Conservative estimates reduce the number of faint galaxies ten times, but it’s just possible that the universe has only one hundredth the faint lurker galaxies we previously thought it did.
We’ll get an idea of whether those estimates are correct when the James Webb telescope goes up in 2018. Rest assured, there are still plenty of galaxies to explore.
[Source: The Astrophysical Journal Letters]