October 21st 05, 05:08 PM
http://www.lowell.edu/press_room/releases/recent_releases/DCTmb.html
For Immediate Release
October 20, 2005
contact:
Steele Wotkyns
Lowell Observatory
(928) 233-3232
Lowell Observatory Announces
Completion of Discovery Channel Telescope Primary Mirror Blank
Flagstaff, Ariz. - Lowell Observatory announces completion of the
4.3-meter-diameter (14 ft.) primary mirror blank for the Discovery
Channel Telescope by Corning, Inc. After two years in production at
the
Corning plant in Canton, New York, the nearly $3-million mirror blank
will be transferred to a different vendor for the two to three-year
polishing process that will yield the ultra-high-precision shape
required of the finished telescope mirror.
Lowell Observatory Director Bob Millis noted that achievement of this
major milestone in the building of the telescope was achieved on time
and within specifications. "Working with the highly skilled
professionals at Corning has been a pleasure," said Millis.
The mirror blank was manufactured by Corning in a multi-step process
that began with production of multiple boules of Corning's patented
ultra-low-expansion glass (ULE?). The ULE boules were shaped to
correct
thickness and fused together to produce a single disk for the mirror
blank. In early 2005, the fused mirror blank went into a large furnace
and was slumped over a mold giving the blank its approximate final
shape. The process ended with grinding the mirror's front surface to
within a couple of mils of the final shape.
"Corning takes great pride in knowing that we have produced a mirror
blank which meets Lowell Observatory's requirements and will enable
scientists to observe the newly discovered Kuiper Belt, explore the
outer solar system, and investigate distant stars and galaxies," said
Andy Filson, Director of Corning's Semiconductor Materials business.
The finished mirror blank weighs about 6,700 lbs and is only 100 mm (4
inches) thick. Relative to its diameter, the mirror blank is very thin.
Such meniscus mirrors have been used in only a handful of other modern
large telescopes. The advantage of such mirrors is their comparatively
light weight and their ability to maintain a temperature close to that
of the surrounding air as the temperature drops during the night.
However, these mirrors are relatively flexible, and accordingly are
supported by an active system that maintains optimum mirror shape
regardless of the orientation of the telescope. A mirror of the
correct
shape in temperature equilibrium is crucial to producing ultra sharp
images of celestial objects.
The Discovery Channel Telescope is a joint project of Lowell
Observatory
and Discovery Communications, Inc. When fully operational in 2010, the
new telescope will allow Lowell astronomers to enter new research areas
and conduct existing programs much more efficiently and effectively.
When completed, the Discovery Channel telescope will be the fifth
largest telescope in the continental United States.
end
Note: A photo of the completed Discovery Channel Telescope mirror blank
is available for download and publication (using credit line and
caption
as stated below) at:
ftp://ftp.lowell.edu/pub/steele
photo caption and credit line: The completed Discovery Channel
Telescope
mirror blank with Corning and Lowell Observatory staff from left to
right: Holly Wisniewski, Bruce Wells, Byron Smith, Matt Mitchell, Larry
Sutton, Bob Millis, Randy VanBrocklin, and Mary Edwards. photo:
Corning,
Inc.
For Immediate Release
October 20, 2005
contact:
Steele Wotkyns
Lowell Observatory
(928) 233-3232
Lowell Observatory Announces
Completion of Discovery Channel Telescope Primary Mirror Blank
Flagstaff, Ariz. - Lowell Observatory announces completion of the
4.3-meter-diameter (14 ft.) primary mirror blank for the Discovery
Channel Telescope by Corning, Inc. After two years in production at
the
Corning plant in Canton, New York, the nearly $3-million mirror blank
will be transferred to a different vendor for the two to three-year
polishing process that will yield the ultra-high-precision shape
required of the finished telescope mirror.
Lowell Observatory Director Bob Millis noted that achievement of this
major milestone in the building of the telescope was achieved on time
and within specifications. "Working with the highly skilled
professionals at Corning has been a pleasure," said Millis.
The mirror blank was manufactured by Corning in a multi-step process
that began with production of multiple boules of Corning's patented
ultra-low-expansion glass (ULE?). The ULE boules were shaped to
correct
thickness and fused together to produce a single disk for the mirror
blank. In early 2005, the fused mirror blank went into a large furnace
and was slumped over a mold giving the blank its approximate final
shape. The process ended with grinding the mirror's front surface to
within a couple of mils of the final shape.
"Corning takes great pride in knowing that we have produced a mirror
blank which meets Lowell Observatory's requirements and will enable
scientists to observe the newly discovered Kuiper Belt, explore the
outer solar system, and investigate distant stars and galaxies," said
Andy Filson, Director of Corning's Semiconductor Materials business.
The finished mirror blank weighs about 6,700 lbs and is only 100 mm (4
inches) thick. Relative to its diameter, the mirror blank is very thin.
Such meniscus mirrors have been used in only a handful of other modern
large telescopes. The advantage of such mirrors is their comparatively
light weight and their ability to maintain a temperature close to that
of the surrounding air as the temperature drops during the night.
However, these mirrors are relatively flexible, and accordingly are
supported by an active system that maintains optimum mirror shape
regardless of the orientation of the telescope. A mirror of the
correct
shape in temperature equilibrium is crucial to producing ultra sharp
images of celestial objects.
The Discovery Channel Telescope is a joint project of Lowell
Observatory
and Discovery Communications, Inc. When fully operational in 2010, the
new telescope will allow Lowell astronomers to enter new research areas
and conduct existing programs much more efficiently and effectively.
When completed, the Discovery Channel telescope will be the fifth
largest telescope in the continental United States.
end
Note: A photo of the completed Discovery Channel Telescope mirror blank
is available for download and publication (using credit line and
caption
as stated below) at:
ftp://ftp.lowell.edu/pub/steele
photo caption and credit line: The completed Discovery Channel
Telescope
mirror blank with Corning and Lowell Observatory staff from left to
right: Holly Wisniewski, Bruce Wells, Byron Smith, Matt Mitchell, Larry
Sutton, Bob Millis, Randy VanBrocklin, and Mary Edwards. photo:
Corning,
Inc.