《欧洲南方天文台决定建设39米极大望远镜主镜全部子镜》

  • 来源专题:天文仪器与技术信息
  • 编译者: zwg@niaot.ac.cn
  • 发布时间:2017-12-15
  • ESO’s governing body, the Council, has just authorised additional spending to cover the cost of both the five inner rings of segments for the main mirror (M1) of the Extremely Large Telescope (ELT), and one spare set of 133 mirror segments (one sixth of the total M1), and also an additional mirror segment maintenance unit. The decision was made at the recent meeting of the Council in Garching, Germany, after the positive recommendation by the ESO Finance Committee and made possible by an improved funding scenario.

    The ELT is a revolutionary ground-based telescope concept which will have a 39-metre main mirror made of 798 hexagonal segments. It will be the largest optical telescope in the world: “the world’s biggest eye on the sky”. First light for the ELT is targeted for 2024.

    Up to now the inner five rings of segments of the ELT primary mirror were in Phase 2 of the project, and had not yet been funded. This second phase also included a mirror segment washing, stripping and coating plant that was needed to keep the mirror at its full performance, as well as a spare set of 133 mirror segments [1]. These parts of the telescope’s Phase 2 have now received the green light.

    Construction of the telescope is proceeding rapidly and nearly 90% of the contracts for Phase 1, by value, are already awarded.

  • 原文来源:http://www.eso.org/public/announcements/ann17085/
相关报告
  • 《欧洲南方天文台签订39米望远镜主镜的子镜支撑合同》

    • 来源专题:天文仪器与技术信息
    • 编译者:zwg@niaot.ac.cn
    • 发布时间:2018-04-30
    • ESO has signed a contract with VDL ETG Projects B.V. (the Netherlands) for the manufacture, assembly, testing and delivery of the Segment Support Mechanics for the primary mirror of ESO’s Extremely Large Telescope (ELT). The segment supports together act as the backbone of the primary mirror, holding each of the 798 mirror segments in place. Sensors and actuators monitor and control each segment’s shape and position to very high accuracy. The contract was signed by Harrie Schonewille, Managing Director of VDL ETG Projects, Willem van der Leegte, President VDL and Xavier Barcons, Director General of ESO, at a ceremony at ESO Headquarters in Garching, Germany on 19 April 2018. When completed, the ELT’s primary mirror (M1) will be 39 metres in diameter and will consist of 798 hexagonal mirror segments. The hexagonal shape means that a common support structure can be used for all segments. Each segment will be connected to the back-structure by means of a segment support system. This is composed of three linkage mechanisms that balance the forces applied and hold the segment via 27 axial actuators and one lateral actuator. The shape of each segment can also be optimised by means of warping harness actuators. Each segment, some 1.4 metres across and weighing 250 kilograms, will be mounted on three position actuators. ELT first light is planned for 2024, when it will begin to tackle the biggest astronomical challenges of our time. The giant telescope is expected to allow the exploration of completely unknown realms of the Universe — it will be “the world’s biggest eye on the sky”.
  • 《欧洲南方天文台签订39米极大望远镜主镜位移促动器合同》

    • 来源专题:天文仪器与技术信息
    • 编译者:zwg@niaot.ac.cn
    • 发布时间:2017-06-22
    • ESO has signed a contract with the German company Physik Instrumente GmbH & Co. KG, based in Karlsruhe, to construct the position actuators (PACTs) that will adjust the positions of the 798 hexagonal segments of the primary mirror of ESO’s Extremely Large Telescope (ELT). The segments that make up the ELT’s enormous 39-metre main mirror will be connected to the main telescope structure via a support system (ann15003), of which the PACTs are fundamental components. Each segment, some 1.4 metres across and weighing 250 kg will be mounted on three PACTs — meaning 2394 in total. The PACTs will support the segment and actively control its position in three directions, known as piston, tip and tilt. The control system of the ELT primary mirror will initiate tiny adjustments to the PACTs to maintain the mirror’s overall shape, correcting for deformations which may be caused by changes in telescope elevation, temperature and wind forces, as well as limiting the effects of vibrations. More Information Physik Instrumente has worked with ESO before, providing the hexapods that align the subreflectors to the large main reflectors of the radio telescopes that make up the Atacama Large Millimeter/submillimeter Array (ALMA).