Building on the discoveries of Renaissance astronomers, the Modern era astronomers have expanded our understanding of the universe. Not only have they helped us understand what the universe is like right now, but these discoveries help explain what happened in the past.

There are four Modern era astronomers to know.


Williamina Fleming discovered that stars change their light intensity over time.

George Hale invented the "spectrohelioscope," which is a tool that shows which gasses and elements that make up stars.





Henrietta Swan Leavitt found out a way to measure the distance of stars from Earth by using their brightness.

The fourth astronomer, Edwin Hubble, will be discussed on the next page. His contributions are some of the most important in the Modern era.



Sources http://www.windows.ucar.edu (permits educational and research use)