The farther the star is, the smaller the angles. For stars more than about 100 light-years from Earth, we cannot measure any shift and the method fails. The mathematical formula of a …

It is not an easy thing to measure the distances to objects in the universe since these objects are usually very far away. We can't just run out there with a ruler! To measure distances in the …

Redshift and Hubble's Law For very far objects (beyond about 1 billion light-years) none of the above methods work. Scientists must move from direct observation to using observations in …

Supernovae At large distances (up to about 1 billion light-years), astronomers can no longer use methods such as parallax or Cepheid variables. At such large distances, the parallax shift …

Cepheids, also called Cepheid Variables, are stars which brigthen and dim periodically. This behavior allows them to be used as cosmic yardsticks out to distances of a few tens of millions …

Galileo Galilei was an Italian physicist and astronomer. He was born in Pisa on February 15, 1564. Galileo's father, Vincenzo Galilei, was a well-known musician. Vincenzo decided that his …

A light-year is a unit of distance. It is the distance that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 …

This modern method of measuring distances is based on the fact that light (whether in the form of radio waves, microwaves, visible light, or X-rays) travels with a speed of 300,000 km/sec. …

Feb 15, 2016 · The parallax is one of the proves. In ancient times, some thinkers realized that if the Earth rotated around the Sun, we would see an oscilation of the "fixed" stars. They didn't …

May 14, 2018 · StarChild is a learning center for young astronomers ages 5-13 to learn about the solar system, the Milky Way galaxy, and the universe beyond. Use the links above to explore …