声化: 子弹星系团的物质

2020年12月16日

Sonified: The Matter of the Bullet Cluster
Image Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI, Magellan/U.Arizona; Lensing Map: NASA/STScI, ESO WFI, Magellan/U.Arizona; Sonification: NASA/CXC/SAO/K.Arcand, SYSTEM Sounds (M. Russo, A. Santaguida)

Explanation: What’s the matter with the Bullet Cluster? This massive cluster of galaxies (1E 0657-558) creates gravitational lens distortions of background galaxies in a way that has been interpreted as strong evidence for the leading theory: that dark matter exists within. Different analyses, though, indicate that a less popular alternative — modifying gravity– could explain cluster dynamics without dark matter, and provide a more likely progenitor scenario as well. Currently, the two scientific hypotheses are competing to explain the observations: it’s invisible matter versus amended gravity. The duel is dramatic as a clear Bullet-proof example of dark matter would shatter the simplicity of modified gravity theories. The featured sonified image is a Hubble/Chandra/Magellan composite with red depicting the X-rays emitted by hot gas, and blue depicting the suggested separated dark matter distribution. The sonification assigns low tones to dark matter, mid-range frequencies to visible light, and high tones to X-rays. The battle over the matter in the Bullet cluster is likely to continue as more observations, computer simulations, and analyses are completed.

Submitted to APOD: Notable images of the 2020 Geminids Meteor Shower

Tomorrow’s picture: twins meteors

声化: 子弹星系团的物质
影像提供: X-ray: NASA/CXC/SAO; Optical: NASA/STScI, Magellan/U.Arizona; Lensing Map: NASA/STScI, ESO WFI, Magellan/U.Arizona; Sonification: NASA/CXC/SAO/K .Arcand, SYSTEM Sounds (M. Russo, A. Santaguida)

说明: 子弹星系团有何重要性？这个大质量星系团（1E 0657-558）的重力透镜扭曲背景星系的方式，被引为支持”暗物质存在于星系团内学说”的强烈证据。然而不同的分析指出，不需要引进暗物质，只使用没那么炫的修正重力理论，就能够解释星系团的动力学行为，并且提出了较可能的前导过程。目前这二种科学假说正在争夺观测的诠释权，所以这是一场不可见暗物质与修正重力理论的对战。暗物质学派如果能找到颠扑不破的例证，就能击退简洁的修正重力理论。在这幅整合哈伯/钱德拉/麦哲伦观测数据的主题声化影像里，红色代表X射线数据，蓝色区块可能就是分落在两侧的暗物质。在此则声化处理里，低音代表暗物质，中音为可见光，而高音则是X射线。不过，随着针对子弹星系团的新观测、电脑模拟和数据分析逐渐出炉，这场争论仍会持续下去。

已提交至APOD: 2020年双子座流星雨的著名图像

明日的图片: meteor sky