How to use in-sentence of “proper motion”:
– The star system was discovered in 1948 by W.J Luyten in the course of compiling a catalogue of stars of high proper motion; he noted its exceptionally high proper motion of 3.37 arc seconds annually and catalogued it as Luyten 726-8.
– The proper motion of Barnard’s Star is ‘sideways’ relative to our line of sight to the Sun of 90kilometers per second.
– For example, Barnard’s star has the largest proper motion of any star, moving 10.3 arcseconds per year.
– Proper motion is useful to astronomers in figuring out how far away a star is from Earth because stars that are close usually have a larger proper motion than stars that are farther away.
– The position at other times can be measured by taking into account proper motion or orbital motion.
– The proper motion of a star is its angular change in position over time as seen from the centre of mass of the Solar System.
– Barnard measured its proper motion as 10.3 arcseconds per year.
