The main image shows the full extent of this 1% cutout, a combination of photometry from the VISible instrument (VIS, with wavelength range 550–900 nm) and the Near-Infrared Spectrometer and Photometer (NISP, here using the Y and H bands). Spanning 132 square degrees of sky, this cutout is located south of the celestial equator, close to the Large Magellanic Cloud in projection. Perhaps the most impressive feature here is the seemingly endless speckling of roughly 100 million galaxies and stars across the whole field of view. In addition to Euclid’s main objective to place constraints of unprecedented precision on the evolution of dark energy and the distribution of dark matter out to z ~ 2, the richness of this map shows the telescope’s great potential for advancing our knowledge of the evolution of structure across a range of much smaller scales.

Also striking in this image are the Milky Way’s diffuse, filamentary arms of dust, known as galactic cirrus for their visual similarity to the everyday cirrus cloud. Though, at a temperature of 25 K, their peak emission is in the far-IR (the reason Planck saw them so starkly), Euclid’s detailed detection of these warm dust grains highlights the telescope’s sensitivity at optical wavelengths. Galactic cirrus is sometimes regarded as a nuisance in extragalactic studies as it impedes observations of the low-surface-brightness Universe, but its characteristics provide important information about our Galaxy’s interstellar medium.

主图显示了这个 1% 切口的完整范围，这是 VISible 仪器（VIS，波长范围 550-900 nm）和近红外光谱仪和光度计（NISP，此处使用 Y 和 H 波段）的光度测量的组合。这个切口横跨 132 平方度的天空，位于天赤道以南，靠近投影中的大麦哲伦星云。也许这里最令人印象深刻的特征是整个视野中大约 1 亿个星系和恒星似乎无穷无尽的斑点。除了欧几里得的主要目标对暗能量的演化和暗物质向 z ~ 2 的分布施加前所未有的精确限制之外，这张地图的丰富性还显示了望远镜的巨大潜力，可以推进我们在一系列更小的尺度上对结构演化的认识。

这张图片中同样引人注目的是银河系弥散的丝状尘埃臂，因其在视觉上与日常卷云相似而被称为银河卷云。尽管在 25 K 的温度下，它们的峰值发射是在远红外线中（这就是普朗克如此明显地看到它们的原因），但 Euclid 对这些温暖尘埃颗粒的详细探测突出了望远镜在光学波长下的灵敏度。银河卷云有时被认为在银河系外研究中令人讨厌，因为它阻碍了对低表面亮度宇宙的观测，但它的特性提供了有关我们银河系星际介质的重要信息。