保护地球，探索宇宙，发现文明
在预测北极地区未来将继续变暖的程度和速度方面，云层是最大的不确定因素之一。根据一年中的不同时间以及它们形成和存在的不断变化的环境，云既可以起到保温的作用，也可以冷却它们下面的海面。 几十年来，科学家们一直认为，北极海冰覆盖面积的减少使得更多的云在海洋表面附近形成。现在，NASA的一项新研究表明，暴露的海洋通过海冰上一个被称为“冰间湖（polynya）”的大洞释放热量和水分，促进了更多云的形成，这些云捕获了大气中的热量，阻碍了新海冰的再冻结。 这一发现来自于一项对位于格陵兰岛和加拿大之间的巴芬湾北部被称为北方水域冰间湖的研究。该研究是最早利用卫星上的主动传感器探测冰间湖与云之间相互作用的研究之一，科学家们可以利用卫星上的主动传感器分析大气中低层和高层的垂直云层。 领导这项研究的美国宇航局汉普顿兰利研究中心的大气科...
2021年9月25日 The Bubble and the Star Cluster Image Credit & Copyright: Lorand Fenyes Explanation: To the eye, this cosmic composition nicely balances the Bubble Nebula at the right with open star cluster M52. The pair would be lopsided on other scales, though. Embedded in a complex of interstellar dust and gas and blown by the winds from a single, massive...
On the night 175 years ago on Sept. 23-24, 1846, astronomers discovered Neptune, the eighth planet orbiting our Sun. The discovery was made based on mathematical calculations of its predicted position due to observed perturbations in the orbit of the planet Uranus. The discovery was made using a telescope since Neptune is too faint to be visible to the naked...
2021年9月24日 Perseid Outburst at Westmeath Lookout Image Credit & Copyright: Pierre Martin Explanation: This year an outburst of Perseid meteors surprised skywatchers. The reliable meteor shower’s peak was predicted for the night of August 12/13. But persistent visual observers in North America were deluged with a startling Perseid shower outburst a...
2021年9月10日，即任务的第198个火星日，NASA的毅力号火星车使用其WATSON相机，在一块绰号为“Rochette”的岩石上拍摄了这张自拍照。照片中可以看到火星车使用其机械臂钻取岩芯样本的两个孔。 图片来源：NASA/JPL-Caltech/MSSS 科学家们利用六轮火星车上的一系列成像仪，获得了这颗红色星球的全景图。 NASA的毅力号火星车已经在杰泽罗火山口探索了超过217个地球日（211个火星日），那里的尘土飞扬的岩石开始讲述它们的故事——关于一个流淌着熔岩和水的年轻火星。 这个绵延数十亿年的故事正在展开，这在很大程度上要归功于毅力号上的七台强大的科学相机。这些特殊的相机能够从很远的距离拍摄到微小的特征，对火星的景观进行大范围的扫描，并放大微小的岩石颗粒，这些相机还帮助火星车团队确定哪些岩石样本提...
The atmospheric glow blankets the Earth’s horizon beneath the stars, as shown in a photo taken while the International Space Station orbited 261 miles above the Pacific Ocean southeast of Japan. 如国际空间站在日本东南的太平洋上空261英里处运行时拍摄的照片所示，大气层的光辉覆盖了星空下的地球地平线。 On Tuesday, Sept. 28, three residents of the station will take a short ride aboard a Soyuz MS-18, relocat...
2021年9月23日 Harvest Moon Trail Image Credit & Copyright: Mike Cohea Explanation: Famed in festival, story, and song the best known full moon is the Harvest Moon. For northern hemisphere dwellers that’s a traditional name of the full moon nearest the September equinox. Seen from Saunderstown, Rhode Island, planet Earth, this Harvest Moon left a broa...
2021年9月22日 Equinox on a Spinning Earth Image Credit: Meteosat 9, NASA, earthobservatory, Robert Simmon Explanation: When does the line between night and day become vertical? Today. Today is an equinox on planet Earth, a time of year when day and night are most nearly equal. At an equinox, the Earth’s terminator — the dividing line between day and...
Time capsules from the birth of our Solar System more than 4 billion years ago, the swarms of Trojan asteroids associated with Jupiter are thought to be remnants of the primordial material that formed the outer planets. The Trojans orbit the Sun in two loose groups, with one group leading ahead of Jupiter in its path, the other trailing behind. Clustered aro...
Space Station Commander Akihiko Hoshide of the Japan Aerospace Exploration Agency conducts research using DNA sequencing to help monitor and identify microbes on spacecraft to increase the safety of future human missions to the Moon, Mars, and beyond. 日本宇宙航空研究开发机构的空间站指挥官星出彰彦（Akihiko Hoshide）利用DNA测序进行研究，以帮助监测和识别航天器上的微生物，以提高未来人类登月、火星等任务的安全性。 Image Credit: NASA...