Guide to the Cosmos
on Radio

Hosted by
Dr. Robert Piccioni


Shop Now

Listen to Robert


About Dr. Piccioni

Free Videos

mailbox Newsletter

Henrietta Leavitt: First Famous Woman Astronomer 

Leavitt was told women couldn't be astronomers,
but she was deaf and didn't hear that.
She went on to solve the biggest challenge in astronomy.

Click here for Broadcast

Image #1

Henrietta Swan Leavitt at her desk at the Harvard Observatory

Henrietta Leavitt

Cepheid variable star

Image #2

A Cepheid variable star in galaxy M100. Below is a major part of M100, with a box around the region with the Cepheid. Above are 3 images of the boxed region taken at different times showing the Cepheid (circled) gradually brightening.

Image #3

Leavitt's discovery of a simple relationship between the period and luminosity of Type 1 Cepheids (yellow), Type 2 Cepheids (red) and RR Lyrae (blue) variable stars.
period and luminosity

Cepheid RR Pup
Image #4

Cepheid RR Pup has a period of 41 days. "Waves" of maximum brightness moving away from the star illuminate the surrounding gas; wave crests are 41 light-days apart. From the angle between the crests that we see on Earth sets the distance to RS Pup, 6500 light-years to a precision of almost 1%.



myspace visitors