Because of this, a set of satellite orbital elements very rapidly "ages" and for accurate predictions 'must' be updated every few days.

所以，人造卫星的轨道计算数据会很快就过期，如果你要准确计算它们的轨道，你就必须即使更新它们。

youdao

And there's actually a way that we can make predictions here, and what I'll tell you is molecular orbital theory predicts that h e 2 does not exist because it's not stabilized in terms of forming the molecule.

其实我们有一种办法可以做出预测，我要告诉你们的是分子轨道,理论预测He2不存在,因为它形成分子不稳定。

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