Assertion: dark matter's gravity | /r/HasProperty | measured via its effects
Facets:
value: on galaxy clusters
type: LOCATION
value: indirectly
type: MANNER
value: on the rotation rates of galaxies
type: OTHER
Source sentences:
text: But dark matter's gravity can be measured indirectly via its effects on galaxy clusters and the rotation rates of galaxies, so we know it's out there.