1642 in science
The year 1642 in science and technology involved some significant events.
Astronomy
- Rundetårn astronomical observatory for the University of Copenhagen is completed, as is also the Panzano Observatory.
Computing
- 19-year-old Blaise Pascal begins to develop the Pascaline, the first practical mechanical calculator, initially to help with the recording of taxes.
Exploration
- November 24 – Abel Tasman, Dutch explorer, is the first European known to sight Tasmania, which he names Anthoonij van Diemenslandt.
- December 13 – Tasman is the first European known to sight New Zealand.
Technology
- Opening throughout of the Briare Canal in France, the first summit level canal in Europe built using pound locks.
- The printmaking process of mezzotint is developed by Ludwig von Siegen.