If we say that a galaxy has a lookback time of 1 billion years, we mean that ________.
A) its light traveled through space for 1 billion years to reach us
B) it is now 1 billion light-years away
C) it was 1 billion light-years away when the light left the galaxy
D) it is 400 million years old
Correct Answer:
Verified
Q52: Collisions between galaxies typically unfold over a
Q70: Given that white dwarf supernovae are such
Q110: Based on the number of galaxies visible
Q111: What two observable properties of a Cepheid
Q112: Current estimates place the age of the
Q116: What does Hubble's law tell us?
A) The
Q117: Current understanding holds that a galaxy's type
Q118: When we use an analogy that represents
Q119: Although the entire universe may be much
Q120: Which of the following is not one
Unlock this Answer For Free Now!
View this answer and more for free by performing one of the following actions
Scan the QR code to install the App and get 2 free unlocks
Unlock quizzes for free by uploading documents