<?xml version='1.0' encoding='utf-8'?>
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    <logical_identifier>urn:nasa:pds:context:telescope:gemini_north-maunakea.8m1</logical_identifier>
    <version_id>1.2</version_id>
    <title>Frederick C. Gillett Gemini North 8.1-m Telescope</title>
    <information_model_version>1.22.0.0</information_model_version>
    <product_class>Product_Context</product_class>
    <Alias_List>
      <Alias>
        <alternate_title>8.1-m Gemini Ritchey-Chretien altazimuth reflector</alternate_title>
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        <modification_date>2026-07-07</modification_date>
        <version_id>1.2</version_id>
        <description>Removed duplicate Internal_Reference entries from Reference_List.</description>
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      <Modification_Detail>
        <modification_date>2025-01-07</modification_date>
        <version_id>1.1</version_id>
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      <Modification_Detail>
        <modification_date>2022-02-24</modification_date>
        <version_id>1.0</version_id>
        <description>Initial export from OLAF</description>
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    <Internal_Reference>
      <lid_reference>urn:nasa:pds:context:facility:observatory.gemini_north-maunakea</lid_reference>
      <reference_type>telescope_to_facility</reference_type>
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    <Internal_Reference>
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      <reference_type>telescope_to_instrument</reference_type>
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  <Telescope>
    <aperture unit="m">8.1</aperture>
    <telescope_longitude unit="deg">204.53096</telescope_longitude>
    <telescope_latitude unit="deg">19.823807</telescope_latitude>
    <telescope_altitude unit="m">4213</telescope_altitude>
    <coordinate_source>Aerial survey - North American (1983) datum</coordinate_source>
    <description>The Gemini Observatory consists of twin 8.1-meter diameter optical/infrared telescopes located on two of the best observing sites on the planet. From their locations on mountains in Hawai'i and Chile, Gemini Observatory's telescopes can collectively access the entire sky.  The Frederick C. Gillett Gemini North telescope is located on Hawaii's Mauna Kea as part of the international community of observatories built to take advantage of the superb atmospheric conditions on this long dormant volcano which rises about 4,214 meters (13,824 feet) into the dry, stable air of the Pacific.   Primary Mirror: Diameter: 8.1 meters/26.58 feet/319 inches Mass: 22.22 metric tonnes/24.5 U.S. tons Composition: Corning Ultra-Low Expansion (ULE) Glass Surface Accuracy: 15.6 nm RMS (Between 1/1000 - 1/10,000 thickness of human hair)`</description>
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