假天文图大观：只有一幅是真的

2021年11月09日

All of These Space Images are Fake Except One
Image Credit: M. J. Smith et al. (U. Hertfordshire)

Explanation: Why would you want to fake a universe? For one reason — to better understand our real universe. Many astronomical projects seeking to learn properties of our universe now start with a robotic telescope taking sequential images of the night sky. Next, sophisticated computer algorithms crunch these digital images to find stars and galaxies and measure their properties. To calibrate these algorithms, it is useful to test them on fake images from a fake universe to see if the algorithms can correctly deduce purposely imprinted properties. The featured mosaic of fake images was created to specifically mimic the images that have appeared on NASA’s Astronomy Picture of the Day (APOD). Only one image of the 225 images is real — can you find it? The accomplished deceptors have made available individual fake APOD images that can be displayed by accessing their ThisIsNotAnAPOD webpage or Twitter feed. More useful for calibrating and understanding our distant universe, however, are fake galaxies — a sampling of which can be seen at their ThisIsNotAGalaxy webpage.

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Tomorrow’s picture: gone in a flash

假天文图大观：只有一幅是真的
影提像供: M. J. Smith et al. (U. Hertfordshire)

说明: 为何要制作这类的假图呢？理由之一是要增进我们对真实宇宙的了解。许多进行宇宙性质量测的天文计画，常使用无人望远镜为夜空拍摄一系列的影像。然后再用先进的电脑演算法，分析这些数位影像，找出和量测其内的恒星和星系之性质。为了校准这些演算法，使用假宇宙的假影像进行测试，可确认演算法是否能正确找出事先故意植入的性质。这幅假天文图集锦，制作的目的是要模仿，NASA每日天文图（APOD）网站先前呈现过的影像。在全部的225张图里，只有一幅是真的，你找得到它吗？这些高明的假图作者，特地为这些假造的APOD影像，建造了可个别浏览的“这是假APOD影像网页”或推特信息条。而对校正与了解遥远宇宙更有用的假星系样本图，可参见“这是假星系网页”。

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明日的图片: gone in a flash