You're likely thinking of Anders Celsius (1701-1744), a Swedish astronomer. While he's best known for the temperature scale that bears his name, Celsius made important contributions to astronomy as well:

1. The Celsius Temperature Scale:

* Invention: Celsius proposed the centigrade scale, later renamed the Celsius scale, in 1742. It defines the freezing point of water as 0 degrees and the boiling point as 100 degrees.

* Impact: The Celsius scale became the standard for measuring temperature in most parts of the world, replacing the Fahrenheit scale used in the United States. Its simplicity and ease of use made it highly practical for scientific and everyday use.

2. Astronomical Observations:

* Northern Lights: Celsius made detailed observations of the aurora borealis (Northern Lights), contributing to the understanding of this natural phenomenon.

* Astronomical Measurements: He established an observatory at Uppsala University and conducted extensive measurements of star positions, contributing to the field of astrometry.

* Cataloging Stars: Celsius created a catalog of approximately 300 stars, providing a valuable resource for astronomers.

3. Advocacy for Scientific Progress:

* Founded the Royal Swedish Academy of Sciences: Celsius was one of the founders of the Royal Swedish Academy of Sciences in 1739, playing a crucial role in promoting scientific research in Sweden.

While his temperature scale is his most recognized contribution, Celsius was a versatile scientist who made significant advancements in astronomy and played a role in promoting scientific progress.