哈勃太空望远镜拍摄“迷失星系”的照片

Located in the constellation of Virgo (The Virgin), around 50 million light-years from Earth, the galaxy NGC 4535 is truly a stunning sight to behold. Despite the incredible quality of this image, taken from the NASA/ESA Hubble Space Telescope, NGC 4535 has a hazy, somewhat ghostly, appearance when viewed from a smaller telescope. This led amateur astronomer Leland S. Copeland to nickname NGC 4535 the “Lost Galaxy” in the 1950s.

The bright colors in this image aren’t just beautiful to look at, as they actually tell us about the population of stars within this barred spiral galaxy. The bright blue-ish colors, seen nestled amongst NGC 4535’s long, spiral arms, indicate the presence of a greater number of younger and hotter stars. In contrast, the yellower tones of this galaxy’s bulge suggest that this central area is home to stars which are older and cooler.

This galaxy was studied as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) survey, which aims to clarify many of the links between cold gas clouds, star formation, and the overall shape and other properties of galaxies. On January 11, 2021 the first release of the PHANGS-HST Collection was made publicly available.

Text credit: European Space Agency (ESA)
Image credit: ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team

NGC 4535星系座落在处女座，距地球约5,000万光年，真是令人惊叹不已。尽管从NASA/ESA哈勃太空望远镜拍摄的这张图像质量令人难以置信，但从较小的望远镜观看时，NGC 4535的外观仍然有些朦胧，有些令人毛骨悚然。这导致业余天文学家利兰·S·科普兰(Leland S. Copeland)在1950年代将NGC 4535昵称为“迷失星系”。

这张图片中的鲜艳色彩不仅看起来漂亮，还可以告诉我们有关该禁止旋涡星系中恒星的数量。 NGC 4535的长长的螺旋形臂中夹杂着明亮的蓝色，表明存在着更多的年轻和炽热的恒星。相反，该星系凸起的黄色表示该中心区域是更古老且温度较低的恒星的所在地。

该星系已作为“邻近星系”（PHANGS）中高角度分辨率物理学的一部分进行了研究，该研究旨在阐明冷气体云、恒星形成和星系整体形状和其他属性之间的许多联系。2021年1月11日，PHANGS-HST系列的第一版公开发布。

文字来源：欧洲航天局（ESA）
图片来源：ESA / Hubble和NASA，J·Lee和PHANGS-HST团队