You've probably seen the viral videos where planes appear to be frozen in the sky, hovering in place rather than flying forward as they usually do. While some are quick to call the situation a glitch ...

The telescope also sees their "parallax" - their apparent looping behaviour, which is a function of Earth and Gaia changing their vantage point as they circle the Sun (It is the parallaxes that ...

To learn more about parallax, try the activities in Project Earth Science: Astronomy, P. Sean Smith, NSTA Publications, 1992. Distances to stars and celestial objects are immense. Cars travel at ...