Monday, 11 January 2016

Famous Wow! Signal Caused by Comets, Not Aliens?

Image courtesy of The Ohio State University Radio Observatory and the North American AstroPhysical Observatory (NAAPO), public domain.

Joel Kontinen

Science fiction and Darwinian evolution have played major roles in shaping the way many people look at the universe. There’s a tendency to assume that life mysteriously pops up almost anywhere it possibly can – without any input from a Designer.

Even brilliant minds have jumped on the alien life bandwagon. Steven Hawking, for instance, has warned earthlings of big bad aliens. Others have speculated that we have already seen them, while some others are planning to communicate with them.

What is needed is a reality check. We don’t know of any other star system expect our own that harbours life, and the search for alien intelligence (SETI) has been marked by false alarms.

The latest to go is the famous Wow! Signal. A recent article in New Scientist gives some background facts:

On 15 August 1977, radio astronomers using the Big Ear radio telescope at Ohio State University picked up a powerful signal from space. Some believe it was our first interception of an alien broadcast.”

Hopes were high when the assumed message was first received:

The signal – known as the “Wow! signal” after a note scribbled by astronomer Jerry Ehman, who detected it – came through at 1420 megahertz, corresponding to a wavelength of 21 centimetres. Searchers for extraterrestrial transmissions have long considered it an auspicious place to look, as it is one of the main frequencies at which atoms of hydrogen, the most common element in the universe, absorb and emit energy. What’s more, this frequency easily penetrates the atmosphere.”

However, the almost 40 years following the signal have been silent ones. Now it seems that the signal was caused by two comets that passed Earth. Antonio Paris, a professor of astronomy at St Petersburg College in Florida came up with this view recently.

He might well be right.


Emspak, Jesse. 2016. Famous Wow! signal might have been from comets, not aliens. New Scientist (11 January).