What can be observed only by observing its effects on gravity?
A. dark matter
B. a solar nebula
C. gas and dust
D. a planetesimal
Answer (2)
The correct answer to the question is dark matter, as it is observable only through its gravitational effects on visible matter. Unlike other celestial objects, dark matter does not emit light, making it invisible and detectable only by indirect methods. Its influence is crucial in the study of galaxies and the universe's formation.
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The phenomenon that can be observed only through its effects on gravity is dark matter, which is inferred from its gravitational influence on visible matter. Unlike other celestial objects, dark matter does not emit light, making it invisible and detectable only by observing its gravitational effects. This has significant implications in astrophysics, particularly in the study of galaxy formation and dynamics. ;
