For ten points, the distance and recession velocity of cosmological objects are related by what constant named for a famous astronomer.
Implicitly required by universal homogeneity and isotropy, its reciprocal is proportional to time since the Big Bang.  Usually given in units of kilometers per second per Megaparsec, constraints on its value come from observing distant Cepheid variables.  For ten points, the distance and recession velocity of cosmological objects are related by what constant named for a famous astronomer.
Implicitly required by universal homogeneity and isotropy, its reciprocal is proportional to time since the Big Bang.  
Hubble constant