â Open Transport Incorporated's implementation action plan focused on a 3 year rolling plan to improve roads highways and bridges to be monitored on an annual basis. â Was this Helpful? YES NO 3 people found this helpful.
This is the missing-mass problem. If this factor of ten holds throughout the Universe, then the total mass in the Universe would be about 6e52 kg. If the missing mass were mostly in the form of hydrogen atoms (which is not at all clear) then the number of atoms would be about 4e79.
According to Magnitudes of Physics , the density of the sun is about 1,410 kilograms per cubic meter. (For comparison, the density of water is 1,000 kilograms per cubic meter.). If you are willing to accept these three assumptions, then: A cubic light year contains about 1E+48 cubic meters. So all of the matter in the universe would fit into about 1 billion cubic light years, or a cube that's approximately 1,000 light years on each side. That means that only about 0.0000000000000000000042 percent of the universe contains any matter. The universe is a pretty empty place!