Mastering Astronomy T-1

Part A Shown here are six galaxies, each labeled with its approximate distance from Earth. Rank the galaxies from left to right based on the amount of time it has taken their light to travel to Earth, from the longest time to the shortest time.

- 10 billion light-years - 5 billion light-years - 2 billion light-years - 800 million light-years - 230 million light-years - 70 million light-years

Part B Consider again the galaxies you ranked in Part A. This time, rank them from left to right based on the age of the universe at the time these galaxies emitted the light we receive from them today, from oldest (closest to today) to youngest (furthest back in time).

- 70 million light-years - 230 million light-years - 800 million light-years - 2 billion light-years - 5 billion light-years - 10 billion light-years

Part A Shown here are astronomical objects located at different distances from Earth. Rank the objects based on their distances from Earth, from farthest to nearest.

- star on far side of Andromeda Galaxy - star on near side of Andromeda Galaxy - star on far side of Milky Way Galaxy - star near center of Milky Way Galaxy - Orion Nebula - Alpha Centauri - Pluto - The Sun

Part B Consider again the objects you ranked by distance in Part A. Suppose each object emitted a burst of light right now. Rank the objects from left to right based on the amount of time it would take this light to reach Earth, from longest time to shortest time.

- star on far side of Andromeda Galaxy - star on near side of Andromeda Galaxy - star on far side of Milky Way Galaxy - star near center of Milky Way Galaxy - Orion Nebula - Alpha Centauri - Pluto - The Sun

Part C Look once more at the objects you ranked in Parts A and B. This time, rank the objects from left to right based on how much they have aged since they emitted the light we see today, from greatest to least.

- star on far side of Andromeda Galaxy - star on near side of Andromeda Galaxy - star on far side of Milky Way Galaxy - star near center of Milky Way Galaxy - Orion Nebula - Alpha Centauri - Pluto - The Sun

Part B Rank the following items that describe distances from longest distance (left) to shortest distance (right). (If two distances are equal, drag the second item on top of the first item.)

- the distance from the Milky Way Galaxy to the Andromeda Galaxy - the distance from the Sun to the center of the Milky Way Galaxy - the distance from Earth to Alpha Centauri - one light-year - the distance across out solar system (to Neptune) - the average distance from Earth to the Sun & one astronomical unit (AU)

Part A Rank the following items according to their size (diameter) from left to right, from largest to smallest.

- the universe - the local supercluster - the Local Group - the Milky Way Galaxy - our solar system - the Sun - Jupiter - Earth