All these Sky Pixels Are Yours The evolution of telescopes and CCD Arrays: The Coming Data...
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Transcript of All these Sky Pixels Are Yours The evolution of telescopes and CCD Arrays: The Coming Data...
All these Sky Pixels Are All these Sky Pixels Are YoursYours
The evolution of telescopes The evolution of telescopes and CCD Arrays: The and CCD Arrays: The
Coming Data NightmareComing Data Nightmare
Once Upon a Time: Life Was Once Upon a Time: Life Was SimpleSimple
• One Big Telescope
• One Thick Mirror
• One Lousy Detector
Thick MirrorsThick Mirrors
Made the support structure of the Made the support structure of the telescopes very expensivetelescopes very expensive
Capital Cost scaled as ACapital Cost scaled as A33
Would be limiting factorWould be limiting factor Thermal IssuesThermal Issues 1948-1982 1948-1982
Solution: Develop Thin MirrorsSolution: Develop Thin Mirrors
Lower Cost for Support StructuresLower Cost for Support Structures Thermal Issues are lessThermal Issues are less
Next: Combine Individual Light Next: Combine Individual Light SourcesSources
First done at the Multiple Mirror Telescope First done at the Multiple Mirror Telescope which was commissioned in 1982which was commissioned in 1982
Thin to Segmented Thin to Segmented MirrorsMirrors
Thin Mirror Technology (including Thin Mirror Technology (including Hubble) would dominate from 1982 Hubble) would dominate from 1982 to about 1998to about 1998
Keck 10 meter segmented mirrorKeck 10 meter segmented mirror
What about Detectors?
Photographic/Film is horrible non linear and no QE
Need a digital detectorBoyle and Smith 1969 CCD Nobel
Prize
Optical InterferometerOptical Interferometer
• Can it work at short wavelengths to combine the light from many mirrors?
But is Big Aperture = Big ScienceBut is Big Aperture = Big Science
Historically not – Historically its survey Historically not – Historically its survey instruments that advance the field.instruments that advance the field.
Here comes the LSST Here comes the LSST
LSST Concept
Single 8.4 M mirror3 degree FOV (!)80% encircled energy = 0.2” (Like HST)10s integration equivalent to 10hr
integration with 200 inch telescope.There are 40,000 square degrees in the
skySo …