By 1673, approximately how long was the refractor constructed by Polish astronomer Johannes Hevelius?

Answer

150 feet (approximately 45 meters)

The optical arms race led Johannes Hevelius to construct a spectacular refractor measuring 150 feet long by 1673 in an effort to manage aberrations by increasing focal length.

By 1673, approximately how long was the refractor constructed by Polish astronomer Johannes Hevelius?
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