Idaho Skies Transcript for January 23rd and 24th

RACHEL
Welcome to Idaho Skies for January 23rd and 24th. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
On January 23rd, 1930, American astronomer Clyde Tombaugh was scanning photographic plates of the sky when he noticed a star that shifted its position between the plates.

PAUL
Tombaugh was a Kansas farm boy who the Lowell Observatory in Flagstaff, Arizona hired in 1929. The founder of the observatory was Percival Lowell and he was certain that there was a planet beyond Neptune, the most distantly known planet known at the time. Therefore, the observatory tasked Tombaugh with searching for this planet by taking photographs of the night sky.   

RACHEL
He was therefore searching for a star-like point that shifted it position from one night to the next just enough for a distant planet. To help him in his search, Tombaugh took pictures of the same star field several nights apart. He then loaded each photographic plate into a light box and then quickly alternated between the two plates. In his blink comparator, stars remained stationary, but moving objects jumped back and forth.

PAUL
He discovered a lot of asteroids this way. In fact, there were so many asteroids in photographic plates that astronomers called them the vermin of the sky. However, Tombaugh knew that a distant planet wouldn’t shift its position as much as an asteroid would. That’s because asteroids orbit closer to the sun and therefore, move more quickly.

RACHEL
Lowell had lucked out, there actually was a more distant planet, but not because of the reasons that he thought. The planet was eventually named Pluto after the Roman god of the underworld. And in 1999, Pluto lost its status as a planet to become the first Kuiper Belt object to be discovered. Eighty-five years after its discovery, the New Horizons spacecraft gave us our first close up look at Pluto when it flew by. 

PAUL
That’s Idaho Skies for the 23rd and 24th of January.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.