Transcript for January 20th to 22nd

RACHEL
Welcome to Idaho Skies for January 20th, 21st, and 22nd. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
Stargazers should start looking for earthshine on the morning of the 22nd.

PAUL
Earthshine is also called the moon’s Ashen Glow.

RACHEL
Stargazers will notice the dark portion of the moon is not actually black.

PAUL
Instead, it’s faintly illuminated.

RACHEL
In binoculars, that illumination is bright enough to show some lunar details.

PAUL
Details like the lunar seas or maria.

RACHEL
We know that the illumination comes from sunlight reflecting off of Earth.

PAUL
It was Leonardo da Vinci in the 1500s that explained the moon’s ashen glow as the result of sunlight reflecting off of Earth.

RACHEL
Did you know that by monitoring earthshine, scientists can determine the percentage of Earth’s cloud cover?

PAUL
That’s because earthshine is brighter when there are more clouds.

RACHEL
Long term variations in cloud cover can be determined this way since there are records of the brightness of earthshine.

PAUL
Earthshine is one example of planetshine.

RACHEL
Planetshine is the general term for the illumination of satellites by the reflection of sunlight off of any planet.

PAUL
And it’s been observed on the moons of Saturn by the Cassini spacecraft.

RACHEL
Planetshine has allowed the spacecraft to map the surfaces of moons when they were not properly illuminated by sunlight.

PAUL
By the way, some of the dark hemispheres of Saturn’s moons were observed using sunlight reflecting off the planets rings.

RACHEL
Let me guess, this is called ringshine.

PAUL
Yep.

RACHEL
That’s Idaho Skies for the 20th, 21st, and 22nd of January.

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

For Idaho Skies this is Paul...

RACHEL
...and Rachel.

RACHEL
Dark skies and bright stars.