Transcript for Febuary 15th to 21st

RACHEL
Welcome to Idaho Skies for the third week of February. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
The moon is new on the 17th.

PAUL
So you should look for Earthshine on the mornings of the 15th and 16th.

RACHEL
And again on the 19th and 20th.

PAUL
Earthshine is sunlight reflected off of the Earth and onto the moon.

RACHEL
Through your binoculars, you’ll see that earthshine faintly illuminates some of the lunar maria on the moon’s dark side.

PAUL
Over 100 years ago, some astronomers hypothesized that a planet existed beyond Neptune, the most distant planet known at the time.

RACHEL
They did because they believed Neptune was not traveling around the sun in a proper orbit.

PAUL
However, it turns out these hypothesizes where based on poor positional data, Neptune actually was traveling around the sun as it should.

RACHEL
One observatory looking for this unknown planet, which they called Planet X, was the Lowell Observatory in Flagstaff, Arizona.

PAUL
They hired Clyde Tombaugh, a Kansas farm boy to photograph regions of the sky at night and then scan the photographic plates during the day.

RACHEL
He was literally looking for a needle in a haystack.

PAUL
That needle was a single faint star that appeared to shift its position relative to millions of fixed stars.

RACHEL
This was very time consuming and Tombaugh required intense concentration and dedication.

PAUL
However it paid off, Tombaugh succeeded in detecting Planet X 85 years ago on the 18th.

RACHEL
His discovery was eventually named Pluto, the Roman god of the underworld.

PAUL
Tombaugh’s planet was tiny, only 1,400 miles across or about 60% the size of the moon.

RACHEL
On average, Pluto is 4.5 billion miles away from the sun or over 45 times farther from the sun that Earth.

PAUL
At that distance, the sun’s gravity is so weak that it takes Pluto 247 years to orbit the sun and its surface temperature is -380 degrees Fahrenheit.

RACHEL
For over 60 years, Pluto was listed as one of the nine planets of the solar system.

PAUL
Late last century, some astronomers argued that Pluto shouldn’t be classified as a planet at all.

RACHEL
Pluto they believed was part of an undiscovered disk of small icy bodies surrounding the outer edge of the solar system.

PAUL
This belt was apparently the home of many of the comets that graced our skies.

RACHEL
It took until 1992, but eventually astronomers began discovering some of these millions of icy bodies.

PAUL
As a result, Pluto got an official demotion.

RACHEL
However, get ready for more news about Pluto and its place in the solar system.

PAUL
That’s because this tiny world will be in the headlines on July 14th.

RACHEL
On that day, the New Horizons spacecraft will visit Pluto during its flyby mission.

PAUL
Much closer to home, look for the young crescent moon on the evening of the 20th.

RACHEL
That evening however, you might first notice much brighter Venus.

PAUL
Just above Venus will be the planet Mars and our moon.

RACHEL
Since the moon will be an incredibly thin crescent, earthshine should be very easy to see once the sky gets dark.

PAUL
If you have a camera, you might want to try taking a few photographs.

RACHEL
That’s Idaho Skies for the third week of February. Many of the comets we see reside inside a belt surrounding the outer edge of the solar system and that’s our topic next week. 

PAUL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul...

RACHEL
...and Rachel.

RACHEL
Dark skies and bright stars.