The largest telescopes in the world

In article
,
Richard DeLuca wrote:



ARRGH!!
20th Century. Gonna take a nap now........


Gosh,
Would you believe I'm doing some public speaking tonight? True, but
sad.....:-(

"Mike Simmons" wrote in message
snip
As with the Sky and Telescope article, it would be interesting to
separate telescopes by design as well. The 40-inch refractor remains
the world's largest of its kind despite being well over a century old.
Surely that deserves some special recognition! :-)

Along the same line of thought, I'd think that there should be a catagory
for single mirrors. The Keck is 10 meters but made up of smaller hexagonal
segments. In 1999, the Subaru telescope had the largest (8.2 meter) single
mirror.


--
terry
19.52°N, 155.92°W

Richard DeLuca wrote:
In article ,
Chris L Peterson wrote:


Fun project. I assume your interest here is in _astronomical_ telescopes? I
only
ask this because I doubt that Galileo's telescope was the largest telescope
in
the world at the time, although it was certainly the first that we know to
have
been used as a truly astronomical instrument. This raises the interesting
question of whether there have been any non-astronomical telescopes since
that
time that were actually the largest telescopes in the world.

________________________________________________ _

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


Chris,

I remember a very interesting article in Sky & Tel several years ago.
It was about a lens or mirror, touted as the world's largest, that was
displayed or possibly even mounted at about the turn of the 19th
century. Either a World's Fair or possibly the Colombian Exposition?
Anyone recall the details??

Starry Skies,
Rich

I recall a lens larger than the Yerkes 40 inch that was displayed at
an exhibition in Europe (Paris?) but not mounted.
Ah ha ... google rules!
http://www.wikipedia.org/wiki/List_o...ing_telescopes

"Paul Schlyter" wrote in
message ...
Currently, the list looks as below. By a curious coincidence
Lord Rosse's 72-inch Leviathan was dismantled in 1908, the same
year that Mount Wilson's 60-inch reflector became operational;

I visited the Science Museum while I was in London (just got back
tonight!) - And they have the original 72-inch mirror from the Leviathan
telescope on display. If I recall correctly, the text which accompanied it
said that the Leviathan telescope was the largest in the world until the
Mount Wilson 100" telescope in 1917. The Leviathan telescope was built in
1842, and was the largest for 75 years (i.e. until 1917 when the Mount
Wilson 100" came along)

Although this page: http://www.lawrencetown.com/birr.htm claims the
Leviathan was dismantled in 1914 - So I don't know who's telling the truth!
If the '75 year' claim for the Leviathan is accurate, then that eliminates
the Mt Wilson 60-inch from the list. Perhaps the Leviathan existed up until
1914, but ceased being functional/operational in 1908 - when it fell into
disrepair?

John.

http://www.irishastronomy.com

Paul Schlyter wrote in message ...

================================================== ============
World's
largest Aperture Scope
scope in

1908-1917 1.5 m 60-inch, Mt Wilson, California, USA; operational
20 Dec
1917-1948 2.5 m Hooker 100-inch, Mt Wilson, California, USA

Between the commissioning of the 60 and 100 inch telescopes on Mount
Wilson, the 72inch Plaskett telescope at the Dominion Astrophysical
Observatory, Victoria, British Columbia was commissioned for the first
time in early 1917 I believe (final configuration in 1918). Being
built at essentially the same time as the Hooker, it is debatable
(depending on what you accept as the completion date of the two
telescopes) whether it was ever the world's largest telescope. But the
DAO staff insist it was for a few months, as it did beat the Hooker to
first light.

Chris L Peterson wrote:

On Tue, 30 Sep 2003 21:58:29 +0200, Paul Schlyter
wrote:


The world's largest telescope today is of course the twin Keck
telescopes, even taken one by one. And before that, the largest
scope was the Russian 6-meter reflector. And before that the Hale
5-meter telescope, and before that the Hooker 2.5-meter telescope.

But before that?

I'd like to assemble a list of the world's largest telescopes, in
chronological order. Ideally it should cover all the time from
Galileo's telescope in 1609 to the present time, and be complete,
but quite naturally available information may be incomplete or
inaccurate particularly from the 1600's and 1700's.

Paul-

Fun project. I assume your interest here is in _astronomical_ telescopes? I only
ask this because I doubt that Galileo's telescope was the largest telescope in
the world at the time, although it was certainly the first that we know to have
been used as a truly astronomical instrument. This raises the interesting
question of whether there have been any non-astronomical telescopes since that
time that were actually the largest telescopes in the world.

Yes, I assumed astronomical telescopes. And I'm quite positive that the
astronomical telescopes were the largest, except possibly in the very
earliest
history of the telescopes as you suggest here. And it may be next to
impossible
to find out which non-astronomical telescope was the largest at that
time....


_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


--
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Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/

Grant Gussie wrote:

Between the commissioning of the 60 and 100 inch telescopes on Mount
Wilson, the 72inch Plaskett telescope at the Dominion Astrophysical
Observatory, Victoria, British Columbia was commissioned for the first
time in early 1917 I believe (final configuration in 1918). Being
built at essentially the same time as the Hooker, it is debatable
(depending on what you accept as the completion date of the two
telescopes) whether it was ever the world's largest telescope. But the
DAO staff insist it was for a few months, as it did beat the Hooker to
first light.

The Hooker saw first light first. The 72-inch Plaskett telescope was
commissioned in 1918. The claim is that the 100-inch -- which saw first
light in 1917 -- was not operational at the time and thus the 72-inch
was the world's largest operational telescope.

Mike Simmons

Paul Schlyter wrote:

Mike Simmons wrote:

Paul Schlyter wrote:

I'd like to assemble a list of the world's largest telescopes, in
chronological order.

I've always been fascinated by this and hoped that someone would put
such a list together. There was a great article in Sky and Telescope a
few years ago that should help but I can't locate it. It had a list of
all of the world's largest telescopes of various designs and included
their commissioning dates. The section on refractors should prove
useful as that's where the older instruments are.

Could you try to remember, to the best of your ability, how many years
ago that article appeared? I have Sky and Telescope since about 40
years back, and can look through them, and it would be nice to have
the search narrowed down as much as possible.

I'm sure it was published no longer ago than 1996. I think it was at
least two years ago but I'm not sure of that. It was a feature article
so it shouldn't be that hard to find. Sky and Tel has an online search
of the archives in its section on buying back issues that can narrow the
candidates considerably. I tried searching it but there were a few
possibilities based on the titles so I wasn't sure which one it was.

1948-1974 5.0 m Hale 200-inch, Mt Palomar, California, USA

The correct location name is "Palomar Mountain".

OK, I've corrected that in my list. But it's "Mt Wilson" and not
"Wilson Mountain" ?

"Mount Wilson" is correct. When first named it was referred to as
"Wilson's Peak" but that name hasn't been used in 100 years. The
original name of the observatory -- at the time of first light of the
60-inch and 100-inch -- was "Mount Wilson Solar Observatory". The word
"Solar" was dropped after dedication of the 100-inch (some time in 1918,
I believe).

Mike Simmons

Ante Perkovic wrote:

Paul Schlyter wrote:

The world's largest telescope today is of course the twin Keck
telescopes, even taken one by one.

Wrong!

It's Arecibo!

:-) ....OK I assumed optical astronomical telescopes.

If we're going to include any kind of telescope, then what about
radio interferometers, like the VLA? Or what about radio telescopes
cooperating interferometrically on different continents, creating
sort of an effective aperture the size of the Earth !!! Compared
to those, Arecibo, Keck etc are midgets !!!! :-)


Ante


--
----------------------------------------------------------------
Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/

Thanks everybody for your comments! I have now updated my list, and I
believe
it's now fairly complete from 1783 and on. Now comes the hardest part:
try to
fill in the holes in the list before 1783.....

It's of course a good idea to consider a telescope the largest in the
world
only when it's operational. Therefore I now consider Lord Rosse's
Leviathan
to be the "king" of telescopes only until 1878, when it was used for the
last
time.

Another good idea is to divide the scopes in categories, and have
separate
lists for reflectors and refractors, and during recent years perhaps
also
a list for reflectors with segmented mirrors. And then we also have the
radio telescopes (yep, Arecibo is much larger than Keck!). And perhaps
we
also should have a list for radio interferometers (e.g. the VLA) and
also
optical interferometers (they'll probably soon be operational, although
the Hooker telescope used an early version of an interferometer decades
ago). And a category by itself would be the astrographs, i.e.
refractors
with 4-lens objectives, designed for the widest possible field of view;
that category ended when the Schmidt telescope appeared. And then we
have Schmidt telescopes and other catadioptric scopes.....

But those will all be future projects. This list is about optical
astronomical telescopes, both refractors and reflectors, and the latter
both single mirror and segmented.



The evolution of telescopes can be divided into several "eras":

1. The chromatic (= single-lens) refractor, from 1609 to perhaps 1730.
This
era culminated with the so-called "air telescopes", i.e. chromatic
refractors
with very large f-ratio and thus very long focal lengths (up to 50-100
meters),
in order to minimize chromatic aberration.

2. The metallic mirror reflector, from ca 1730 to 1878, which culminated
with
William Herschel's telescopes and Lord Rosse's Leviathan. The end of
this era
also marked the end of the era when the world's largest telescopes were
owned
by amateur astronomers.

3. The achromatic refractor: During 1878-1889 the world's largest
telescopes were
refractors. The evolution of big refractors met a dead end with the
Yerkes
refractor 1897 - no other operational refractor has ever been larger.

4. The sigle glass mirror reflector, from 1889 to 1993. These
telesscopes were
very successful and are now the most common scopes even among amateur
astronomers.

5. The multiple (segmented) mirror reflector, from 1993 and on. Future
large mirrors
will most likely be mostly segmented.

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



So here's what my list looks today. Comments and suggestions are still
welcome,
but I think I'll have to dig through many issues of Sky and Telescope
for more
info about the time period prior to 1783 (when Herschel's 0.43 meter
reflector
of 20 feet focal length became operational). That'll take some time, so
it'll
probably take awhile before I post a significantly updated version of
this list.
But whenever I have more info, I'll post it!



-----------------------------------------------------------------------------------
World's
largest Aperture Scope
scope in

1609 0.044 m Galileos 5-6 foot f.l. refractor, x33
1640 ca ? 15-20 foot refractors
1656 0.07 m Christian Huygens 23 f.l. foot refractor, x100
1670 ca ? Hevelius 140 foot refractor
1675 The "air telescope"

1730 ca Large reflectors

1774 William Herschel starts making telescopes

1783-1789 0.43 m William Herschel's 20 foot f.l. reflector, Bath,
England
Later used by John Herschel in South Africa
1789-1839 1.22 m William Herschel's 40 foot f.l. reflector, Bath,
England
Destroyed in a gale 1839
1839-1845 0.91 m Lord Rosse's first reflector with 3-foot
aperture, built in 1826
1845-1878 1.83 m Lord Rosse's Leviathan, 6 foot aperture, Birr
Castle, Ireland
Last used in 1878
Deteriorated rapidly from 1908
Dismantled in 1914 - mirror moved to Science
Museum
Restored in 1998 with a modern glass mirror
(original mirror remains at Science Museum)
1878-1887 0.69 m Refractor, Vienna Observatory, Austria
1887-1888 0.76 m Refractor, Cote d'Azur Observatory, Nice, France
1888-1889 0.91 m Refractor, Lick Observatory, Mt Hamilton, USA
1889-1908 1.52 m A.A. Common's 60-inch reflector; purchased by
Harvard
University around 1900
(1898-... 1.57 m John Peate's 62-inch mirror for the American
University
Observatory; never mounted in a telescope)
1908-1917 1.52 m 60-inch reflector, Mt Wilson, California, USA
1917 1.83 m 72-inch Plaskett reflector, Dominion
Astrophysical Observatory,
Victoria, British Columbia, Canada (largest for
a few months)
1917-1948 2.5 m Hooker 100-inch reflector, Mt Wilson, California,
USA
1948-1974 5.0 m Hale 200-inch reflector, Palomar Mountain,
California, USA
1974-1993 6.0 m BTA-6, Mt Pashtoukov, Caucasus, Russia
1993-2003 9.8 m Keck, Mauna Kea, Hawaii, USA
2003- 10.4 m CTC, Canary Islands, Spain



Interesting links related to the history of telescopes:
-------------------------------------------------------

Some early telescope history:
http://es.rice.edu/ES/humsoc/Galileo...telescope.html

Binocular history:
http://inventors.about.com/library/i...ltelescope.htm

Lots of links related to telescope and binocular history:
http://home.europa.com/~telscope/binotele.htm

Some historical telescopes:
http://www.space.com/scienceastronom...00913_MB_.html

Herschel museum:
http://www.bath-preservation-trust.o...hel/index.html
http://peterchow.com/photos/United-K...rschel-Museum/

Lord Rosse's Leviathan:
http://www.labbey.com/Telescopes/Parsontown.html
http://www.arm.ac.uk/history/birr6.html
http://www.astrosurf.com/lombry/univers-rosse.htm

Largest telescopes today:
http://www.wikipedia.org/wiki/List_o...ing_telescopes
http://www.wikipedia.org/wiki/List_o...ing_telescopes
http://www.seds.org/billa/bigeyes.html



--
----------------------------------------------------------------
Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/