A study that evaluates sci-fi scenarios for extraterrestrial encounters, published in the journal Acta Astronautica, said that E.T. could decide whether we're a threat to intergalactic order and may try to kill us. 

At the heart of these scenarios is the possibility that intrinsic value may be more efficiently produced in our absence, the researchers wrote.  Humanity benefits not only from the major moral victory of having defeated a daunting rival but also from the opportunity to reverse-engineer ETI [extraterrestrial intelligence] technology, the researchers added.

The researchers also said that there may be great payoffs if we win. 

The 33-page study carefully evaluated the potential risks of a hostile alien encounter, citing that the possibility of harmful contact with ETI suggests that we may use some caution for METI [sending messages to extaterrestrial intelligence] and that given that we have already altered our environment in ways that may be viewed as unethical by universalist ETI, it may be prudent to avoid sending any message that shows evidence of our negative environmental impact. The chemical composition of Earth's atmosphere over recent time may be a poor choice for a message because it would show a rapid accumulation of carbon dioxide from human activity. Likewise, any message that indicates widespread loss of biodiversity or rapid rates of expansion may be dangerous if received by such universalist ETI.

The study began to frighten the general population after the media released headlines such as NASA REPORT: Aliens may destroy humanity to protect other civlizations... and NASA: Aliens May Destroy Humanity Over Greenhouse Gases.

One of the study's authors, postdoctoral student Shawn Domagal-Goldman, who works at NASA Headquarters, initiated the controversy.  Domagal-Goldman, who admitted that the NASA affiliation was a horrible mistake, issued a public apology.  It was just a fun paper written by a few friends, one of whom happens to have a NASA affiliation, Domagal-Goldman wrote.

NASA was forced to post the following Twitter update: Yes, @drudge and @guardiannews are mistaken about an 'alien' report. It's not NASA research. Ask the report's author.... 

On the bright side, New York Times columnist Paul Krugman said last weekend that an alien invasion hoax may facilitate economic salvation.