哈勃望远镜瞥见一个闪烁的星系团

The glittering, glitzy contents of the globular cluster NGC 6652 sparkle in this star-studded image from the NASA/ESA Hubble Space Telescope. The core of the cluster is suffused with the pale blue light of countless stars, and a handful of particularly bright foreground stars are adorned with crisscrossing diffraction spikes. NGC 6652 lies in our own Milky Way galaxy in the constellation Sagittarius, just under 30,000 light-years from Earth and only 6,500 light-years from the galactic center.

Globular clusters are stable, tightly gravitationally bound clusters containing anywhere from tens of thousands to millions of stars. The intense gravitational attraction between closely packed stars in globular clusters is what gives these star-studded objects their regular, spherical shape.

This image combines data from two of Hubble’s most powerful cameras: the Advanced Camera for Surveys and Wide Field Camera 3. It also uses data from two different observing programs conducted by two different teams of astronomers. The first team set out to survey globular clusters in the Milky Way galaxy in the hope of shedding light on topics ranging from the ages of these objects to the gravitational potential of the galaxy as a whole. The second team of astronomers used a trio of exquisitely sensitive filters in Hubble’s Wide Field Camera 3 to disentangle the proportions of carbon, nitrogen, and oxygen in globular clusters such as NGC 6652.

Text credit: European Space Agency (ESA)
Image credit: ESA/Hubble & NASA, A. Sarajedini, G. Piotto

在这张由NASA/ESA哈勃太空望远镜拍摄的众星云集的照片中，球状星团NGC 6652的内部物质闪闪发光。星团的核心充满了无数恒星发出的淡蓝色光，少数特别明亮的前景恒星点缀着纵横交错的衍射尖峰。NGC 6652位于银河系人马座，距离地球不到3万光年，距离银河系中心只有6,500光年。

球状星团是稳定的，被引力紧密束缚的星团，包含着数万到数百万颗恒星。球状星团中紧密排列的恒星之间强烈的引力使这些恒星云集的物体具有规则的球形。

这幅图像结合了哈勃最强大的两台相机的数据：高级巡天相机和广角相机3。它还使用了由两个不同的天文学家团队进行的两个不同观测项目的数据。第一个团队开始调查银河系中的球状星团，希望能揭示从这些天体的年龄到整个星系的引力势等主题。第二组天文学家使用哈勃广角相机3上的三个非常灵敏的滤镜来解开球状星团（如NGC 6652）中碳、氮和氧的比例。

文字来源：欧洲航空局（ESA）
影像来源：ESA/Hubble & NASA, A. Sarajedini, G. Piotto