Which of the following best summarizes what we mean by dark matter?
A. matter that we have identified from its gravitational effects but that we cannot see in any wavelength of light
B. matter that may inhabit dark areas of the cosmos where we see nothing at all
C. matter consisting of black holes
D. matter for which we have theoretical reason to think it exists, but no observational evidence for its existence
Answer:A
Which of the following best summarizes what we mean by dark matter?
A. matter that we have identified from its gravitational effects but that we cannot see in any wavelength of light B. matter that may inhabit dark areas of the cosmos where we see nothing at all C. matter consisting of black holes D. matter for which we have theoretical reason to think it exists, but no observational evidence for its existence