ユークリッド宇宙望遠鏡が暗黒の宇宙に光を当てる
ロンドン大学ユニバーシティ・カレッジ2023年8月2日
ESA の Euclid ミッションは、宇宙の 2 つの謎に満ちた構成要素である暗黒物質と暗黒エネルギーの性質を調査し理解するために欧州宇宙機関 (ESA) によって実施された非常に野心的なプロジェクトです。 2023 年 7 月 1 日に打ち上げられたこの探査機は、これまでに作成された中で最も正確な宇宙の 3D 地図を構築するために、最大 100 億光年離れた数十億の銀河を観測します。 クレジット: ESA
Euclid, a space mission led by the European Space AgencyThe European Space Agency (ESA) is an intergovernmental organization dedicated to the exploration and study of space. ESA was established in 1975 and has 22 member states, with its headquarters located in Paris, France. ESA is responsible for the development and coordination of Europe's space activities, including the design, construction, and launch of spacecraft and satellites for scientific research and Earth observation. Some of ESA's flagship missions have included the Rosetta mission to study a comet, the Gaia mission to create a 3D map of the Milky Way, and the ExoMars mission to search for evidence of past or present life on Mars." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">欧州宇宙機関(ESA)は、ユニバーシティ・カレッジ・ロンドン(UCL)の研究者によって設計・製作された巨大な光学カメラを備えており、暗黒物質と暗黒エネルギーという2つの神秘的な構成要素をより深く理解するために、宇宙の大規模構造を地図に描く予定である。
星、銀河、花、私たちの体、原子など、私たちが周囲の世界で見たり検出したりできるものはすべて、宇宙のわずか 5% にすぎません。 現在の理論によれば、残りは暗黒物質と暗黒エネルギーという 2 つの要素で構成されています。 それらの存在は間接的に推測されます。 暗黒物質は銀河を一つにまとめます。 暗黒エネルギーは宇宙の膨張を加速させています。 しかし、それらが何であるかは不明です。 この謎を解明するために、現在、望遠鏡が宇宙に打ち上げられています。
UCL ムラード宇宙科学研究所のトム キッチング教授は、欧州宇宙機関主導のユークリッド ミッションの科学コーディネーター 4 人のうちの 1 人です。 彼は、それが持ち帰るデータは、ダークエネルギーが「真空エネルギー」、つまり空の空間に現れたり消えたりする仮想粒子のエネルギーであるかどうかを決定する可能性があると述べています。 もしそうなら、この真空エネルギーは現在の理論の予測よりもはるかに強力である必要があるため、素粒子物理学の基本理論を修正する必要があります。 そうでない場合、アインシュタインの重力理論が間違っている可能性があります。 「どちらの方法でも物理学における革命となるでしょう」と彼は言います。
2019年、フランス、カンヌのタレス・アレニア・スペース敷地内にあるユークリッド宇宙船のレプリカ。クレジット: Stephane Corvaja/ESA
このミッションは大規模な共同プロジェクトであり、これを提案したコンソーシアムだけでも 15 か国の 2,000 人の科学者とエンジニアで構成されています。 望遠鏡には 2 つの機器があります。 1 つの近赤外分光光度計 (NISP) は、目に見えない近赤外スペクトルの光を捕捉します。 もう 1 つは VIS と呼ばれ、可視光を捕捉します。 マーク・クロッパー教授 (UCL ムラード宇宙科学研究所) (下の写真) は、UCL、オープン大学、およびヨーロッパ全土のチームと協力して、16 年以上にわたり VIS 光学カメラの設計と開発を主導してきました。
UCLムラード宇宙科学研究所のマーク・クロッパー教授。 クレジット: UCL
このカメラはこれまで宇宙に送られた最大のものの一つで、100億年前に遡り、夜空の3分の1をカバーする宇宙の広い範囲の高解像度のパノラマ画像を撮影する予定だ。 これらのデータを使用して、天文学者は 20 億の銀河の形状を測定し、弱い重力レンズと呼ばれる技術を使用して、遠くの銀河からの光が望遠鏡に向かう途中で介在する物質の重力によってどのように曲げられるかを観察し、大規模な銀河の形状を推測します。これまでよりも正確に可視物質と暗黒物質を分布させることができます。
VIS’s wide field of view means that, while it will take images nearly as sharp as the Hubble Space TelescopeThe Hubble Space Telescope (often referred to as Hubble or HST) is one of NASA's Great Observatories and was launched into low Earth orbit in 1990. It is one of the largest and most versatile space telescopes in use and features a 2.4-meter mirror and four main instruments that observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. It was named after astronomer Edwin Hubble." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"Hubble Space Telescope, it will cover a much larger area of the sky – covering the same area in one day as Hubble covered over 25 years. Each image would require 300 high-definition TV screens to display. Over six years it will allow the shape of more than 1.5 billion galaxies to be measured. “These are huge, unprecedented images,” says Professor Cropper./p> The laboratory, located in a Victorian mansion in the Surrey Hills, is staffed by 60 engineers and 140 scientists. It has supported 300 space missions. Instruments designed and built at MSSL have reached many corners of the solar system, from MarsMars is the second smallest planet in our solar system and the fourth planet from the sun. It is a dusty, cold, desert world with a very thin atmosphere. Iron oxide is prevalent in Mars' surface resulting in its reddish color and its nickname "The Red Planet." Mars' name comes from the Roman god of war." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">Mars to SaturnSaturn is the sixth planet from the sun and has the second-largest mass in the Solar System. It has a much lower density than Earth but has a much greater volume. Saturn's name comes from the Roman god of wealth and agriculture." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"Saturn to close to the Sun, and have helped illuminate the most distant galaxies. A model of Britain’s first rocket, the Skylark, sits at the bottom of a staircase./p> When I visit shortly before the Euclid launch, engineers in a clean room (pictured above) are testing a plasmaPlasma is one of the four fundamental states of matter, along with solid, liquid, and gas. It is an ionized gas consisting of positive ions and free electrons. It was first described by chemist Irving Langmuir in the 1920s." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"plasma analyzer for a space weather satellite, Vigil (due to launch in the mid-2020s), by firing ions at it. Nitrogen is piped in through tubes to keep instruments cold, mimicking the environment in space./p> This process — part of the ground segment, or ground-based element of the mission — is painstaking but crucial. “Every step of the ground segment has to be perfectly done,” says Professor Joachimi. “Any tiny mistake can mess up the science that comes out at the end. Some of the accuracyHow close the measured value conforms to the correct value." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"accuracy requirements can be measured as parts per million.” Euclid’s sharp view of galaxies – its increased resolution compared to previous surveys of the universe – “ups the ante on how accurately we have to process that information.”/p> On July 1, 2023, Euclid successfully launched aboard a SpaceXCommonly known as SpaceX, Space Exploration Technologies Corp. is a private American aerospace manufacturer and space transport services company that was founded by Elon Musk in 2002. Headquartered in Hawthorne, California, the company designs, manufactures, and launches advanced rockets and spacecraft. SpaceX's ultimate goal is to reduce space transportation costs and enable the colonization of Mars." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">SpaceX Falcon 9 rocket from Cape Canaveral Space Force Station in Florida, USA. Its instruments were turned on 11 days later. The spacecraft has now reached the second Lagrangian Point, a stable hovering spot about 1.5 million kilometers (1 million miles) from Earth, joining the NASAEstablished in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is "To discover and expand knowledge for the benefit of humanity." Its core values are "safety, integrity, teamwork, excellence, and inclusion." NASA conducts research, develops technology and launches missions to explore and study Earth, the solar system, and the universe beyond. It also works to advance the state of knowledge in a wide range of scientific fields, including Earth and space science, planetary science, astrophysics, and heliophysics, and it collaborates with private companies and international partners to achieve its goals." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">NASA-led James Webb Space TelescopeThe James Webb Space Telescope (JWST or Webb) is an orbiting infrared observatory that will complement and extend the discoveries of the Hubble Space Telescope. It covers longer wavelengths of light, with greatly improved sensitivity, allowing it to see inside dust clouds where stars and planetary systems are forming today as well as looking further back in time to observe the first galaxies that formed in the early universe." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"James Webb Space Telescope and the ESA Gaia mission: UCL-MSSL provided parts of both of those missions too./p>Euclid, a space mission led by the European Space AgencyThe European Space Agency (ESA) is an intergovernmental organization dedicated to the exploration and study of space. ESA was established in 1975 and has 22 member states, with its headquarters located in Paris, France. ESA is responsible for the development and coordination of Europe's space activities, including the design, construction, and launch of spacecraft and satellites for scientific research and Earth observation. Some of ESA's flagship missions have included the Rosetta mission to study a comet, the Gaia mission to create a 3D map of the Milky Way, and the ExoMars mission to search for evidence of past or present life on Mars." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"European Space Agency (ESA) that includes a massive optical camera designed and built by University College London (UCL) researchers, will map the large-scale structures of the universe to better understand two mysterious components: dark matter and dark energy./strong>