How is astronomical distance determined? Just cannot get my head around cepheid variables, parallax, etc. How is it possible to tell how far away something is when you cannot bounce a radar beam off ...

A wide open space (It could be your backyard or a park.) Two Hula-Hoops (Alternatively, you could use two flat rocks or bricks that you can sit on.) A yardstick or meterstick (Use one that has clear ...

One of the greatest problems that confronts astronomers at the present time is an accurate knowledge of the distances of stars. From the earliest times, the relative positions of stars or their ...

Through a new digital archive, the University of Pittsburgh is making six decades of astronomy research available to scientists and ambitious armchair astronomers. The archive, called the Parallax ...

Astronomical distances are best measured by trigonometric parallax — using the annual shift in star position caused by Earth's motion around the Sun to derive distance. Now James Miller-Jones of the ...