Assertion: star's motion | /r/HasProperty | milli-arcseconds masper year
Facets:
value: in right ascension
type: TEMPORAL
Source sentences:
text: Vega's proper motion is 202.03 ± 0.63 milli-arcseconds (mas) per year in right ascension—the celestial equivalent of longitude—and 287.47 ± 0.54 mas/y in declination, which is equivalent to a change in latitude.