在34亿光年之外，天文学家发现了一个快速增长的超大质量黑洞H1821+643，其活动性出乎意料地低，气体密度却更高。 3.4 billion light-years away, astronomers found a rapidly growing supermassive black hole, H1821+643, with unexpectedly low activity and higher gas density.

天文学家在34亿光年外发现了一个快速增长的超大质量黑洞H1821+643，这并不符合预期。 Astronomers discovered a rapidly growing supermassive black hole, H1821+643, 3.4 billion light-years away, which is not living up to expectations. 利用美国宇航局钱德拉X射线天文台和甚大阵列，研究人员发现类星体对其周围环境的影响比其他星团中的许多巨型黑洞要小。 Using NASA's Chandra X-ray Observatory and the Very Large Array, researchers found that the quasar has less influence on its surroundings than many giant black holes in other clusters. 分析显示，星系中心黑洞附近的气体密度较高，温度也低于预期。 The analysis revealed a higher density of gas near the black hole at the galaxy's center, with lower temperatures than expected.