Feedback on a scheme to cloak Earth from hostile aliens

David Kipping doesn’t want to hide from aliens.

By Hamish Johnston at the APS April Meeting in Salt Lake City 

Earlier today I caught up with David Kipping of Columbia University in the US after his fascinating talk about what could make an exoplanet habitable. I wanted to ask Kipping about a quirky paper that he and Alex Teachey published a few weeks ago, which I wrote about in the The Red Folder.

Kipping and Teachey described how a laser could be used to cloak the Earth from the prying eyes of an extraterrestrial civilization. The paper was published just before 1 April, so at the time I wasn’t sure whether the paper was legitimate (it is) and Kipping told me that publishing before April Fools’ Day did cause some confusion.

So what feedback has Kipping had about the paper?

“Why bother?” and “What a waste of resources” were two unhelpful comments. More constructive criticism came from people who pointed out that an intelligent alien observer would easily see through Kipping’s ruse.

On a positive note, Kipping told me that the paper has inspired others to come up with new ways of cloaking the Earth. Kipping’s scheme guards against the detection of Earth by aliens using the transit method – others are now working on schemes for hiding the wobble of the Sun caused by its planets and even preventing the direct observation of light from Earth.

Does Kipping think that we should try to hide from alien civilizations? No, but his research tells him that it could be done – at least in principle using a relatively small amount of energy.