保护地球，探索宇宙，发现文明
2023年8月21日 Introducing Comet Nishimura Credit & Copyright: Dan Bartlett Explanation: Will Comet Nishimura become visible to the unaided eye? Given the unpredictability of comets, no one can say for sure, but it currently seems like a good bet. The comet was discovered only ten days ago by Hideo Nishimura during 30-second exposures with a standard digita...
2023年1月31日 A Triple View of Comet ZTF Image Credit & Copyright: Javier Caldera & Miguel Gracia Explanation: Comet ZTF has a distinctive shape. The now bright comet visiting the inner Solar System has been showing not only a common dust tail, ion tail, and green gas coma, but also an uncommonly distinctive antitail. The antitail does not actually le...
2023年1月9日 Tails of Comet ZTF Image Credit & Copyright: Jose Francisco Hernández Explanation: Comet ZTF may become visible to the unaided eye. Discovered early last year, this massive snowball has been brightening as it approaches the Sun and the Earth. C/2022 E3 (ZTF) will be closest to the Sun later this week, at which time it may become visible even w...
2022年12月24日 Comet 2022 E3 (ZTF) Image Credit & Copyright: Dan Bartlett Explanation: Comet C/2022 E3 (ZTF) was discovered by astronomers using the wide-field survey camera at the Zwicky Transient Facility this year in early March. Since then the new long-period comet has brightened substantially and is now sweeping across the northern constellation Coron...
2021年12月30日 The Further Tail of Comet Leonard Image Credit & Copyright: Daniele Gasparri Explanation: Comet Leonard, brightest comet of 2021, is at the lower left of these two panels captured on December 29 in dark Atacama desert skies. Heading for its perihelion on January 3 Comet Leonard’s visible tail has grown. Stacked exposures with a wide an...
2021年03月08日 Three Tails of Comet NEOWISE Image Credit & Copyright: Nicolas Lefaudeux Explanation: What created the unusual red tail in Comet NEOWISE? Sodium. A spectacular sight back in the summer of 2020, Comet NEOWISE, at times, displayed something more than just a surprisingly striated white dust tail and a pleasingly patchy blue ion tail. Some color...
2020年7月22日 The Structured Tails of Comet NEOWISE Image Credit & Copyright: Zixuan Lin (Beijing Normal U.) Explanation: What is creating the structure in Comet NEOWISE’s tails? Of the two tails evident, the blue ion tail on the left points directly away from the Sun and is pushed out by the flowing and charged solar wind. Structure in the ion tail ...
2020 January 27 Comet CG Evaporates Image Credit & License: ESA, Rosetta, NAVCAM Explanation: Where do comet tails come from? There are no obvious places on the nuclei of comets from which the jets that create comet tails emanate. One of the best images of emerging jets is shown in the featured picture, taken in 2015 by ESA’s robotic Rosetta spacec...
