The data come from NASA's orbiting Chandra X-ray Observatory, which between 2000 and 2009 took occasional observations of Cassiopeia a (cas a), a neutron star 11,000 light-years from Earth.

数据来源于NASA的钱德拉X射线轨道天文台，该天文台在2000年至2009年偶然观测了Cassipeia a (Cas a)这颗距离地球11000光年的中子星。

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