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《Flash Physics: LIGO resumes its search, sound moves magnetic domains, asteroid is tiny and bright》

  • 来源专题：水声领域信息监测
  • 编译者： ioalib
  • 发布时间：2016-12-12

  • The Laser Interferometer Gravitational-wave Observatory (LIGO) – a pair of gravitational-wave detectors in Hanford, Washington, and Livingston, Louisiana – have been turned back on following almost a year of upgrades. On 11 February, the LIGO collaboration announced the first-ever direct observation of gravitational waves, which were generated by the collision of two black holes 1.3 billion light-years away. This was followed by the announcement of a second gravitational-wave detection on 15 June, also from merging black holes. The detections were made during LIGO's first run from September 2015 to January 2016, and since then engineers have been making improvements to the facility's lasers, electronics and optics. The Livingston detector now has about a 25% improvement in sensitivity, allowing it to spot black-hole mergers at greater distances. The sensitivity of the Hanford detector, meanwhile, is similar to the first run, however the power of the laser has been increased and the detector is more stable, increasing the time that the detector is operational. "Already LIGO has exceeded our expectations, and, like most of the scientific world and beyond, I am excited to see what a more sensitive, upgraded LIGO will detect next," says National Science Foundation director France Córdova. The detectors are now expected to run for around six months before undergoing further maintenance and upgrades.

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  • 《引力波天文台LIGO发起公民科学项目--”重力间谍”》
    • 来源专题：天文仪器与技术信息
    • 编译者：zwg@niaot.ac.cn
    • 发布时间：2016-10-24
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  • 《Slovakia to send its first ever satellite into space》
    • 来源专题：中国科学院紫金山天文台科技信息监测服务
    • 编译者：zhoubz
    • 发布时间：2016-04-12
    • April 11th, 2016 Artist’s rendering of the skCUBE in space. Image Credit: SOSA Slovakia is gearing up to launch its first satellite to orbit with the aim of demonstrating the country’s ability to carry out scientific experiments in space. The pocket-sized one-unit CubeSat, named skCUBE, is currently slated for liftoff in June atop SpaceX’s Falcon 9 rocket from the Cape Canaveral Air Force Station in Florida. The central European state is one of the last countries on the continent to have its own satellite. Weighing about 2.2 lbs. (1 kg), skCUBE is a 4-inch (10-centimeter) cube that will carry an onboard computer, a communications system and a small camera to conduct experiments when orbiting Earth. The main goal of this project is to demonstrate that Slovakia is capable of doing highly sophisticated space research. “We see the development of skCUBE as a first spark of light in showing the world that Slovakia belongs to countries with a potential in space science and industry. 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Many Slovak companies support the project with their know-how, qualified employees and also financially. SkCUBE satellite being presented at a press conference on Jan. 7, 2016. Photo Credit: SOSA “SkCUBE is developed and built by Slovak engineers and scientists as a national project demonstrating an excellent cooperation of our state, universities, students, companies and other supporters, such as astronomy fans,” Labajova said. The tiny spacecraft is fitted with an electricity supply system, a sensory system and an orientation control instrument. The camera onboard the satellite will be capable of taking images with a resolution of 750 x 480 pixels. Its angle of view is 60 degrees and it contains infrared and neutral density filters. SkCUBE will focus on ham radio experiments that will include connection of two amateur radio operators via the satellite, sending of basic telemetry data via Morse code for easy listening and high speed data and image transmission via the 2.4 GHz band. 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