I would imagine that dark matter would be attracted to areas of higher mass density like star systems, as the stronger gravity would pull them in. Would this mean that the solar system would have a mini dark matter halo? If so, would this have an observable effect on the orbits of the planets? submitted by /u/verrma [visit reddit] [comments ..read more

submitted by /u/missvocab [visit reddit] [comments ..read more

I've been thinking about all this recently. I've been playing with the idea that our universe is just a black hole to a host galaxy in a host universe. It seems that we can account for about 5% of stuff in our universe and we have an issue with all this missing stuff. Since gravity can communicate between a galaxy and its black hole, and since a black hole can be about 5% of the galaxy, wouldn't this explain it? And CBR is just stuff falling into the black hole (our universe)? submitted by /u/7_7_7_343 [visit reddit] [comments ..read more

Hey! As an indie developer and astronomy lover i have decided to create an app for learning interesting facts on astronomy and space exploration in the format of quiz. It is called Space Academy and available in the App Store. I hope you will have fun with it! I will also appreciate your thoughts on my app. submitted by /u/yanandera [visit reddit] [comments ..read more

From what I understand within galaxies and inside the space between galaxies that are close enough, gravity is strong enough to overpower the effects of the universes expansion. My question is does expansion occur within these spaces and gravity just keeps cosmological structures intact? Or does the presence of a strong gravitational field stop the expansion from actually occurring? submitted by /u/NoSatisfaction9969 [visit reddit] [comments ..read more

For example, how far apart would the milky way need to be from Andromeda for space between them to increase from dark energy, vs their gravity keeping them at the same distance / coming together (excluding gravity impact of other galaxies in our cluster, if the 2 galaxies were in a void). submitted by /u/db720 [visit reddit] [comments ..read more

submitted by /u/le_bok94 [visit reddit] [comments ..read more

I have heard that the expansion of space does not apply within gravitationally bound structures, such as between the stars in a galaxy. If this is true, why does space expand only when there's nothing around? Or does space technically expand at the same rate everywhere, but within a galaxy it's just so little as to be negligible? submitted by /u/yallakoala [visit reddit] [comments ..read more

I am very new in the study of cosmology so please forgive me and be patient. I’ve been incredibly curious about black holes and how they form, work, and die. My current topic I’m looking into is hawking radiation, but the seemingly basic principles of “virtual particles” really stumps me. How are there particles, or anything for that matter, within space? Isn’t space literally just “space” with nothing in it? What are these particles and how do they exist, let alone react with each other? Where do they come from? What makes them virtual? Why have I never heard about them in other areas of cos ..read more

Hi, looking for a serious cosmologist with an even more serious sense of humor. Working on a film script that requires s a factual (miss) representation of the elements and history of the universe as backdrop for the main story. I need help making the milieu/ world building rock solidly accurate before I take my comedic liberties. DM me if interested. submitted by /u/shamus_gumshoe [visit reddit] [comments ..read more