PAUL
Welcome to Idaho Skies for
the week of January 27th. We’re your hosts, Paul…
STEPHEN
…and Stephen.
PAUL
German astronomer Johannes Hevelius was born on the 28th
in 1611. Since most of our listeners are not familiar with this astronomer,
let’s talk about him and his telescopes. Johannes was originally a beer brewer.
Then after studying jurisprudence, he settled down in his hometown to become an
astronomer.
STEPHEN
In 1641, Johannes started building telescopes on the roofs
of building. Since lens back then were of poor quality, astronomers had to compensate
by increasing their focal lengths. For example, one of Johannes’ first long
telescopes was twelve feet long. And his telescopes were about to get a lot larger
than that.
PAUL
And by large, we mean large. Johannes eventually made
telescopes 60 and 70 feet long. He even built a telescope 150 feet long in
1673. These were called aerial telescopes and they had open tubes. The lenses
were held in place with a series of wires. It took a crew to move these
telescopes around.
STEPHEN
Johannes was encouraged to use his telescopes to collect
data. Unfortunately, the long and cumbersome telescopes were not a good fit for
this. Nonetheless, he did spend four years making lunar maps. They were
spectacular for the time and today we still consider Johannes the founder of
lunar topography.
PAUL
That’s Idaho Skies
for the week of January 27th.
STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this
week’s event reminders and sky maps.
For Idaho Skies this is Stephen…
PAUL
…and Paul.
STEPHEN
Dark skies and bright stars.
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