Approximately how often does a supernovae occur in a typical galaxy?
If a star were rushing towards Earth at a high speed
An example of a standard candle is
If a galaxy that is 10 Mpc away is receding at 700km/s, how far would a galaxy be receding if it were 20 Mpc away?
The "apparent" magnitude of a star is
In the essay "Why the sky is dark at night", a graph of velocity versus distance is shown. What is odd about those galaxies in the Virgo cluster (circled in the graph)?
Why was it important to observe supernovae in galaxies that are close to us?
What if clouds of dust blocked the light from distant stars? Could that allow for an infinite and static universe?