The star Ross 128 has a parallax of 0.301 arcsec, a radial velocity of 13 km/s, and a proper motion of 1.40 arcsec per year. At what total velocity does Ross 128 travel through space, relative to the Sun?

Question

Quizplus · Accepted Answer

To calculate the total velocity of Ross 128, we need to add up its radial velocity and proper motion.

Total velocity = radial velocity + proper motion

Total velocity = 13 km/s + (1.40 arcsec/year * 0.301 arcsec) * (3.086*10^13 km/parsec) * (1 year/365.25 days) * (1 day/24 hours) * (1 hour/3600 seconds)

Total velocity = 26 km/s

Therefore, the best choice is D.

The Star Ross 128 Has a Parallax of 0