One of the common questions we always ask when dealing with cosmic topics, is the distance of an object or phenomenon from Earth. This Google hangout by the Space Telescope Science Institute should help shed some light on this topic.
This Hubble hangout was hosted by Tony Darnell of Space Telescope Science Institute with Dr. Mario Livio and winner of the 2011 Nobel Prize in Physics (for discovering that the universe is accelerating as it expands), Dr. Adam Riess. One of the concepts discussed was the “Hubble Concept” – which postulates how fast the distant galaxies of the universe are moving away from us.