Descendant of Newton's apple tree gravitates to UW

May 23, 2001

by Terry Devitt

A direct descendant of the apple tree that bore the falling fruit that inspired the notion of gravitation by Sir Isaac Newton is being donated to UW-Madison by U.S. Rep. F. James Sensenbrenner.

The tree, which was presented to Sensenbrenner by the National Institute of Standards and Technology for his service as chair of the House of Representatives Committee on Science, will be planted and dedicated this Friday, May 25, at 11 a.m. in the UW-Madison Botanical Garden.

The tree is a graft of the original, which grew in the garden of Newton's mother. Newton was staying at the home when he did his early work on gravitation in 1665-66. According to accounts of Newton's work, the English scientist was aware at the time that there was a force pulling the moon toward the center of the Earth and that force prevented the moon from leaving its orbit around our planet. He also knew how great the force might be and how it must decrease with distance from the Earth. Pondering the phenomenon in his garden, the falling apple inspired calculations that showed that the moon and the apple were pulled by the same force. The work became a pillar of physics, linking physics and astronomy and providing clues to the motions of the moon, the sun, the planets and the stars.

In addition to enhancing the Botanical Garden with a feature of historic importance, the tree will be used for educating UW-Madison students and has already been incorporated into the summer Botany 101 curriculum.

A graduate of the Law School, Sensenbrenner served as chair of the House Science Committee from 1995 to 2000. As chair, he played a key role in oversight and support of the public scientific enterprise in the United States. He now chairs the House Judiciary Committee.

The planting and dedication of the tree, open to news media, will take place in the Botanical Garden behind Birge Hall. The garden is at the intersection of University Avenue and Mills Street.