哈勃望远镜瞥见一个闪烁的星团
The teeming stars of the globular cluster NGC 6544 glisten in this image from the NASA/ESA Hubble Space Telescope. This cluster of tightly bound stars lies more than 8,000 light-years away from Earth and is, like all globular clusters, a densely populated region of tens of thousands of stars. This image of NGC 6544 combines data from two of Hubble’s instruments, the Advanced Camera for Surveys and Wide Field Camera 3, as well as two separate astronomical observations. The first observation was designed to find a visible counterpart to the radio pulsar discovered in NGC 6544. A pulsar is the rapidly spinning remnant of a dead star, emitting twin beams of electromagnetic radiation like a vast astronomical lighthouse. This pulsar rotates particularly quickly, and astronomers…