The largest telescopes in the world

On Thu, 2 Oct 2003 10:32:42 +0000 (UTC), (Paul
Schlyter) wrote:

In article ,
Alan Moore wrote:

On Wed, 01 Oct 2003 19:57:48 +0200, Paul Schlyter
wrote:

snip

(Will we ever see a segmented refractor? :-)

Wasn't it Frauenhofer who used a split objective lens refractor to
measure the distance to 61 Cygni? First measurement of stellar
parallax, IIRC...

The parallax of 61 Cygni was first measured by Bessel, not
Fraunhofer. And I think he used a quite ordinary achromat.

I wen't back and checked. Fraunhofer was the maker of the telescope,
and it did have a split objective, to form two images, close together,
to allow accurate measurement of small angular separations, rather
after the fashion of a split-image rangefinder.

Al Moore

In article 4qHhb.55811$AH4.54917@lakeread06,
John Oliver wrote:

As noted before the soon (we hope) to be largest 10.4m Gran
Telescopio Canarias is the GTC, not CTC. Probably not ready for
prime time until 2005.

Thanks; I've updated that page accordingly.

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