McNaught's Matinee
Credit & Copyright: Stefan Seip - Inset: David Levy
Explanation:
Comets grow bright when they're close to the Sun, basking in the intense solar radiation. Of course, they're also usually impossible to see against the overwhelming scattered sunlight. But surprising Comet McNaught - whose January 12 closest approach to the Sun (perihelion passage) was well inside the orbit of Mercury - gave an enjoyable performance in bright blue daytime skies. In fact, comet expert David Levy captured this remarkable inset (upper left) telescopic view of McNaught within an hour of perihelion, with the comet in broad daylight only about 7 degrees away from the Sun's position. Stefan Seip's wider daytime view of the comet and fluffy clouds was recorded approximately a day later. Seip used a polarizing filter and a telescope/camera set up near Stuttgart, Germany. No longer visible in broad daylight, Comet McNaught is now touring twilight southern skies.
說明:
當彗星越來越接近太陽時，亮度也會增加，很像是沐浴在強烈的太陽輻射裡。通常在白天是很難用肉眼看到，因為太陽散射光太強。 但是令人驚訝的麥克諾特彗星最接近太陽時，它的 近日點(perihelion passage)位置 比水星的軌道還接近太陽，彗星的亮度高到能在大白天 欣賞。 事實上，彗星專家(David Levy)拍攝到這張相當不錯的照片(在左上角)，當彗星在近日點位置附近一個小時，大約距離 太陽的位置只有七度。 隔了一天，史蒂芬(Stefan Seip)利用 廣角鏡頭 捕捉彗星的影像。 史蒂芬使用偏極化的濾鏡、望遠鏡及相機，裝置在德國。 麥克諾特彗星目前在 南天的星空中，在白天是看不到的。
可參考: 日地關係觀測衛星拍攝的麥克諾特彗星
加泰隆尼亞上空的麥克諾特彗星
麥克諾特彗星 - 近數十年來最亮的彗星
朝向太陽的麥克諾特(McNaught)彗星
南半球天空的彗星
日期: 01/19/2007
資料來源: Scientific American
Department of Physics, NCKU
