Curiosity Drives Over a New Kind of Terrain
The Curiosity Mars Rover took this image with its Mast Camera (Mastcam) on Feb. 10, 2019 (Sol 2316).
按月归档： 2 月 2019
Sharpest Ultima Thule
2019 February 28 Sharpest Ultima Thule Image Credit: NASA, Johns Hopkins University APL, Southwest Research Institute, National Optical Astronomy Observatory Explanation: On January 1, New Horizons swooped to within 3,500 kilometers of the Kuiper Belt world known as Ultima Thule. That’s about 3 times closer than its July 2015 closest approach to Pluto....
宇宙有三分之一的质量不知所踪？它们的藏身之处终于被揭晓了
Credits: Illustration:Springel et al. (2005); Spectrum: NASA/CXC/CfA/Kovács et al. 为了找寻一种听起来不太像会消失的东西，天文学家已经花费了好几十年的时间，这种东西你大概不能想象，那就是宇宙中三分之一的“正常“物质。NASA 钱德拉 X 射线天文台 [ Chandra X-ray Observatory，NASA 于 1999 年发射的一颗X射线天文卫星，用于观测天体的 X 射线辐射，是一种空基望远镜（space-based telescope），以下简称“钱德拉” ] 或许能帮助我们解决这一难题，定位到这些遁形远世的大量消失之物。 [rml_read_more] 借助相互独立且得到公认已久的多次探测数据，科学家已经能准确地计算出...
Magnetic Orion
2019 February 27 Magnetic Orion Image Credit & Copyright: NASA, SOFIA, D. Chuss et al. & ESO, M. McCaughrean et al. Explanation: Can magnetism affect how stars form? Recent analysis of Orion data from the HAWC+ instrument on the airborne SOFIA observatory indicate that, at times, it can. HAWC+ is able to measure the polarization of far-infrared light...
Earnest C. Smith in the Astrionics Laboratory in 1964
Earnest C. Smith in the Astrionics Laboratory in 1964.
Simulation TNG50: A Galaxy Cluster Forms
2019 February 26 Simulation TNG50: A Galaxy Cluster Forms Video Credit: IllustrisTNG Project; Visualization: Dylan Nelson (Max Planck Institute for Astrophysics) et al. Music: Symphony No. 5 (Ludwig van Beethoven), via YouTube Audio Library Explanation: How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer sim...
Alvin Drew Works on the International Space Station
NASA astronaut Alvin Drew participated in the STS-133 mission’s first spacewalk.
新发现海王星的小卫星，其实来自海卫八？
新发现的这颗小卫星被天文学家称为“不该存在的卫星”。 2013 年的时候，行星科学家用 NASA 的哈勃空间望远镜（ Hubble Space Telescope）发现了一颗围绕海王星（Neptune）的神秘卫星，但直到多年之后的今天，他们才终于想出了一个说法来解释这颗小卫星的存在。 这个名为“海马”（Hippocamp）的小卫星与海王星另一个更大的卫星异常接近，这颗大卫星就是我们熟知的海卫八（Proteus）。通常情况下，像海卫八这样的卫星会对自己的运行轨道进行“清理”，利用引力的作用将较小的卫星扫到一边或是直接吞并。 那么，为什么海马这颗小卫星却会存在呢？海马很可能是数十亿年前较大的卫星与彗星碰撞后留下的碎片，这颗极小的卫星直径只有 20 英里（约 34 公里），是海卫八（直径约 418 公里）质量的千分之...
Red Sprite Lightning over Kununurra
2019 February 25 Red Sprite Lightning over Kununurra Image Credit & Copyright: Ben Broady Explanation: What are those red filaments in the sky? It is a rarely seen form of lightning confirmed only about 30 years ago: red sprites. Recent research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as 100-me...
The Expanding Echoes of Supernova 1987A
2019 February 24 The Expanding Echoes of Supernova 1987A Video Credit & Copyright: David Malin, AAT Explanation: Can you find supernova 1987A? It isn’t hard — it occurred at the center of the expanding bullseye pattern. Although this stellar detonation was first seen in 1987, light from SN 1987A continued to bounce off clumps of interstellar ...