Scientists know planets form out of the discs of material around young stars, but theory says the transition from dust disc to planetary system is rapid and few objects are caught during this phase.

科学家们知道行星是从年轻的恒星周围的物质盘中形成的，但是理论认为从尘埃盘到行星系统的转变非常快，人们很少见到在这一阶段的物体。

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At this point the quality of the planets in the energy accumulation phase, there is no loss of quality, nothing to do with gravity smaller.

此时行星处在质量能量积累阶段，不存在质量的损失，同引力变小无关。

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Astronomers who have been observing the star since 2005 have determined that as the star expanded into the red giant phase, it destroyed one of its own planets.

FORBES: Astronomers Discover A Star That May Have Destroyed Its Own Planet