Lincoln and the Moon

Antionette Wilkins

On February 9, 2018 The CCBC Catonsville Campus held an event called “Young Mr. Lincoln and the Moon” at the Banneker Planetarium in the Mathematics and Science Hall.

The show was put together by Professor David Bradstreet of Eastern University in Philadelphia, PA to demonstrate how a young lawyer name Abraham Lincoln was able to use the phases of the moon to prove the innocence of his client.

Before Abraham Lincoln became the President of the United States, he was a country lawyer. He had a client named William “Duff” Armstrong. Armstrong was accused of murdering James Preston Metzker a few minutes before midnight of August 29, 1857.

Lincoln was a friend of the accused man’s father Jack Armstrong, who’d just died, and so he offered to defend Duff Armstrong without pay as a favor to Jack Armstrong’s widow. The prosecution had a witness named Charles Allen who testified that he’d seen the murder occur from about 150 feet away.

Lincoln asked Allen how he could tell it was Armstrong if it was in the middle of the night and that he was far away. Allen replied, “By the light of the moon.”

That’s where Allen went wrong. Lincoln produced a copy of the 1857 edition of the almanac, turned to two calendar pages for August and showed the jury that not only was the moon in the first quarter but it was riding “low” on the horizon, about to set.

There wouldn’t have been enough light for Allen to identify Armstrong or anyone else. The jury agreed with Lincoln and Armstrong was acquitted.

The audience at the Banneker Planetarium got to see how the different moon phases ride low and high on the horizon. The show demonstrated how the moon’s phase depends on its position relative to Earth and the sun. At the exact time of the murder, when the moon is at first quarter the moon lies perpendicular to a line between Earth and the Sun. Only half the moon is illuminated by the sun, the other half lies in shadow.

Besides seeing a story being told by using astronomy, there were other attributes added to the show. In the beginning Professor Bradstreet included the scene from the 1939 Frank Capra film "Young Mr. Lincoln" starring Henry Fonda. It was the trial scene when Lincoln played by Fonda proved Armstrong’s innocence.

“I’ve never seen that movie before but watching that scene made me want to watch the whole movie. I want to know more about that story,” said Audience member, Ja’Bria Ross.

Another thing that he included was the theme song from the TV series called “Perry Mason” that began in the late 50’s. It provided a theme for the show because "Perry Mason" was about a defense attorney that defended people that were falsely accused.

The Banneker Planetarium puts on many shows throughout the year. For information on upcoming shows visit:

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