Assertion: asteroid belt's object | /r/HasProperty | mass
Facets:
Source sentences:
text: During a year spent in close orbit (5–56 km [3–35 miles]) around Eros, NEAR Shoemaker studied the object’s mass, structure, geology, composition, gravity, and magnetic field.
text: Additionally, other objects in the Solar System are massive enough to exert gravitational forces significant enough to alter the orbit of smaller objects.