照亮暗物质
Dark matter, although invisible, makes up most of the universe’s mass and creates its underlying structure. Dark matter’s gravity drives normal matter (gas and dust) to collect and build up into stars and galaxies. Although astronomers cannot see dark matter, they can detect its influence by observing how the gravity of massive galaxy clusters, which contain dark matter, bends and distorts the light of more-distant galaxies located behind the cluster.
As seen in this image, large galaxy clusters contain both dark and normal matter. The immense gravity of all this material warps the space around the cluster, causing the light from objects located behind the cluster to be distorted and magnified. This phenomenon is called gravitational lensing. This sketch shows paths of light from a distant galaxy that is being gravitationally lensed by a foreground cluster.
In 1609, visionary scientist Galileo Galilei turned the newly invented optical device of his day — the telescope — to view the heavens. Almost four centuries later, the launch of NASA’s Hubble Space Telescope aboard the space shuttle Discovery in 1990 started another revolution in astronomy. Developed as a partnership between the United States space program and the European Space Agency, Hubble orbits 340 miles above Earth’s surface.
Along with pictures of the telescope and the astronauts who launched and serviced it during six space shuttle missions, certain memorable science images have become cultural icons. They appear regularly on book covers, music albums, clothing, TV shows, movies and even ecclesiastical stained-glass windows.
Explore thirteen representative topics with eye-catching images and thought-provoking discoveries.
Additional images and information can be found at https://hubblesite.org.
Image Credit: NASA/ESA
暗物质虽然看不见，却构成了宇宙的大部分质量，并创造了它的基本结构。暗物质的引力驱使普通物质(气体和尘埃)聚集并形成恒星和星系。虽然天文学家看不见暗物质，但他们可以通过观察含有暗物质的大质量星系团的引力如何弯曲和扭曲位于星系团后面的遥远星系的光线来探测暗物质的影响。
如图所示，大的星系团既包含黑暗物质也包含正常物质。所有这些物质的巨大引力扭曲了星系团周围的空间，导致位于星系团后面的物体发出的光被扭曲和放大。这种现象被称为引力透镜效应。这张草图显示了来自遥远星系的光的路径，该星系正被前景星系团引力透镜化。
1609年，远见卓识的科学家伽利略·伽利莱（Galileo Galilei）转动了他当时新发明的光学设备-望远镜，以观察天空。近四个世纪后，1990年发现号航天飞机发射了NASA的哈勃太空望远镜，掀起了天文学的又一场革命。哈勃望远镜是美国太空计划与欧洲航天局之间的合作开发的，它绕地球表面340英里飞行。
连同在六次航天飞机飞行中发射和维修过的望远镜以及宇航员的照片一起，一些令人难忘的科学图片已经成为文化符号。它们定期出现在书的封面、音乐专辑、服装、电视节目、电影，甚至是教堂的彩色玻璃窗上。
有关其他图像和信息，请访问https://hubblesite.org。
图片来源：NASA/ESA