这幅插图描述了I型X射线爆发。这种类型的X射线爆发首先吹散氢层，氢层膨胀并最终消散。之后，不断增强的辐射积聚到一定点后会吹散氦层，氦层会超过膨胀的氢层。爆发过程中发射出的一些X射线从吸积盘上散射开来。然后火球迅速冷却，氦又重新回到脉冲星表面。 版权：NASA戈达德太空飞行中心/Chris Smith ，大学空间研究联合会（USRA） 美国东部时间8月20日晚10点04分左右，美国国家航空航天局（NASA）在国际空间站的中子星内部成分探测望远镜（Neutron star Interior Composition Explorer，NICER）探测到X射线的突然激增。这次X射线爆发是由脉冲星表面的 […]
Astronomers using data from the Chandra X-ray Observatory and other telescopes have put together a detailed map of a rare collision between four galaxy clusters. Eventually, all four clusters – each with a mass of at least several hundred trillion times that of the Sun – will merge to form one of th
The galaxy pictured in this Hubble image has an especially evocative name: the Medusa merger. Often referred to by its somewhat drier New General Catalogue designation of NGC 4194, this was not always one entity, but two. An early galaxy consumed a smaller gas-rich system, throwing out streams of st
The center of our Milky Way galaxy is hidden from the prying eyes of optical telescopes by clouds of obscuring dust and gas. But in this stunning vista, the Spitzer Space Telescope’s infrared cameras penetrate much of the dust, revealing the stars of the crowded galactic center region. The upc
Discovered in 2018 by NASA’s Transiting Exoplanet Satellite Survey (TESS) mission, planet LHS 3844b is located 48.6 light-years from Earth and has a radius 1.3 times that of Earth. It orbits a small, cool type of star called an M dwarf – especially noteworthy because, as the most common
In our vast universe, the heaviest black holes grew from seeds. Nourished by the gas and dust they consume, or by merging with other dense objects, these seeds grow in size and heft to form the centers of galaxies, such as our own Milky Way. But unlike in the realm of plants, the seeds of giant blac
Many of the best-loved galaxies in the cosmos are remarkably large, close, massive, bright, or beautiful, often with an unusual or intriguing structure or history. However, it takes all kinds to make a universe — as demonstrated by this Hubble image of Messier 110. Messier 110 may not look like much
Located in the northern constellation of Ursa Major, which also includes the Big Dipper, nearby galaxy Messier 81 is easily visible through binoculars or a small telescope. M81 is located at a distance of 12 million light-years. M81 was one of the first publicly released datasets soon after the laun
This image from the NASA/ESA Hubble Space Telescope shows NGC 5307, a planetary nebula that lies about 10,000 light-years from Earth. It can be seen in the constellation Centaurus (the Centaur), which can be seen primarily in the southern hemisphere. A planetary nebula is the final stage of a Sun-li
Sixteen years ago, NASA launched its Spitzer Space Telescope into orbit around the Sun. Since the observatory launched on Aug. 25, 2003, it has been lifting the veil on the wonders of the cosmos, from our own solar system to faraway galaxies, using infrared light. Spitzer’s primary mission las
