The Gaia spacecraft view of the whole sky: it’s measured the motion of two billion stars (ESA/Gaia/DPAC, CC BY-SA 3.0 IGO) We all know Edmond Halley because he’s immortalised by the comet that bears ...

Astronomers have long been able to measure the movement of stars in our 'line of sight' (i.e. the movement towards or away from us) by measuring the redshift, which is caused by the Doppler effect.

Home > Extreme Astronomers Successfully Measure the Motion of 66 Nearby Galaxies A team of astronomers has used the ESA's Gaia spacecraft to get insight into our celestial neighbors, determining the ...