"We can detect sunspots at a depth of 60,000 kilometers, but if we try to detect them deeper or closer to the surface, the travel-time shift becomes weaker," Ilonidis says.

“我们能探测六万公里深处的黑子，但如果探测更深些或者更靠近太阳表面的位置时，(声波的)传播时间的变化将变得不明显，”Ilonidis说。

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"We can detect sunspots at a depth of 60, 000 kilometers, but if we try to detect them deeper or closer to the surface, the travel-time shift becomes weaker," Ilonidis says.

“我们能探测六万公里深处的黑子，但如果探测更深些或者更靠近太阳表面的位置时，(声波的)传播时间的变化将变得不明显，”Ilonidis说。

youdao

"We can detect sunspots at a depth of 60, 000 kilometers, but if we try to detect them deeper or closer to the surface, the travel-time shift becomes weaker," Ilonidis says.

“我们能探测六万公里深处的黑子，但如果探测更深些或者更靠近太阳表面的位置时，(声波的)传播时间的变化将变得不明显，”Ilonidis说。

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