So it appears as a diffuse group of stars covering a huge segment of the night sky -- an area 50 times that of the scoop on the Big Dipper.
"Maybe it's multiple clumps, or maybe it's very diffuse and forming stars over a large volume," Dey says.
The moral is that not only the universal expansion will never end, but the universe will die a death of excessive "thinness" as space becomes ever more diffuse of matter, stars die out, and galaxies disappear.
Last year, astronomers turned an array of small telescopes named Dragonfly on the famous Coma cluster of galaxies, located 340 million light-years from Earth, and discovered 47 "ultra-diffuse" galaxies whose stars are so spread out from one another that they look like ghostly phantoms.
There is now little dust remaining to form the diffuse nebulae where new stars are created, so the stellar population is dominated by old, population II stars that contain relatively low abundances of elements other than hydrogen and helium.
Dust is found to be present in a wide variety of astrophysical environments, ranging from circumstellar envelopes around evolved stars to diffuse and dense interstellar clouds and star-forming regions, and from protoplanetary disks around young stars to active galactic nuclei and distant objects.
"Some of this gas will fall into galaxies, but most of it will remain diffuse and never form stars. "The light from the quasar is like a flashlight beam, and in this case we were lucky that the flashlight is pointing toward the nebula and making the gas glow.
Emission nebula, in astronomy, a bright, diffuse light sometimes associated with stars whose temperatures exceed 20,000 K.
He supposed that stars began as diffuse red giants in the upper right corner of his diagram, became hotter (moving to the left) and eventually became denser, cooler and fainter as they moved down the diagonal line marked by the majority of stars on the "Russell diagram".
