一较为普遍的意见是它们由想要传达给我们信号、警告或其他信息的外星人创造。

One popular theory is that they are created by extraterrestrials who are trying to give us signs, warnings, or other information.

youdao

据悉，这项研究由美国国家航空和宇宙航行局和美国宾夕法尼亚大学研究团队发出的警告还是着实让一些渴望与外星人变朋友的人们感到失望，两个部门近日在起草一份名为：《与外星生物联系的利弊》中详尽勾勒出了倘若有机会与外星人“面对面”后的益处、客观效应还有弊端。

The report, a joint effort between Nasa and Pennsylvania State University, answered the question 'Would Contact With Extraterrestrials Benefit Or Harm Humanity?'

youdao

当然，外星智慧生物也可能生来就侵略成性，所以，和斯蒂芬·霍金前不久前的警告一样，前述研究报告作者们也认为：也许我们不该向太空中发送太多信息。

Of course, ETI might just be an aggressive race, so like Stephen Hawking's recent warning, the authors of the study suggest that perhaps we shouldn't transmit too much information into space.

youdao