101 Facts You Didn't Know about Space by Thompson Mark;

Author:Thompson, Mark;
Language: eng
Format: epub
Tags: SCIENCE / Astronomy
Publisher: Pen & Sword Books Limited
Published: 2020-08-27T00:00:00+00:00

FACT 51

The first telescope mirrors used arsenic

The first astronomical telescopes used lenses to focus incoming starlight but the original designs suffered from an optical effect known as chromatic aberration. The incoming light was a mixture of all ‘colours of the rainbow’ but their different wavelengths meant the simple telescope lens focussed them at different points. An astronomer looking through one of these telescopes would see an image surrounded by colour halos as the different components of light focussed at different points. In the seventeenth century, Isaac Newton was credited as the first person to develop a telescope using spherical curved mirrors instead of lenses to remove the unwanted effects of chromatic aberration. This was largely successful but other unwanted optical effects plagued the reflecting telescope as they became known.

The mirror of the Hubble Telescope being made. (NASA)

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.