Idaho Skies Transcript for March 23rd, 24th, and 25th

RACHEL
Welcome to Idaho Skies for March 23rd, 24th, and 25th. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
The moon reaches first quarter this weekend.

PAUL
Scan along the terminator of the moon with binoculars or telescope and you’ll see lots of concavities on the moon.

RACHEL
These were first discovered by Galileo in 1609.

PAUL
The concavities are so small that it took Galileo’s first telescope to see even the largest one.

RACHEL
Galileo described them as depressions and not as mountains like some later astronomers did.

PAUL
His name for them, crater, comes from the name for a shallow cup.

RACHEL
Since their discovery, many astronomers wonder what was their cause.

PAUL
We’re familiar with volcanoes, so many geologists and astronomers believed that craters had a volcanic origin.

RACHEL
It was English astronomer Richard Anthony Procter who first made people seriously consider meteor impacts as their origin.

PAUL
Procter, by the way, was born 181 years ago on the 23rd.

RACHEL
Even into the mid 1960s, astronomers and geologists remained divided into two crater camps.

PAUL
The Vulcanists argued that lunar craters were the result of volcanoes on the moon.

RACHEL
The other camp, the Impact Theorists, argued that craters were the result of meteor impacts on the moon.

PAUL
There remained two camps until geologist Gene Shoemaker convinced scientists that Meteor Crater in Arizona was the result of a meteor impact on Earth.

RACHEL
And that was a scant four years before the first Apollo moon landing.

PAUL
Today, astronomers and geologists use crater densities as a tool for comparing the ages of planetary surfaces.

RACHEL
They can because they now understand craters are formed from a rain of meteors.

PAUL
And the more craters in a given area, the longer that area has been exposed to meteors.

RACHEL
That’s Idaho Skies for the 23rd, 24th, and 25th of March.

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.

PAUL
Dark skies and bright stars.