Monday, November 9, 2015

No Radio Signals from KIC 8462852

Well that didn't take long. The SETI folks used the Allen Telescope Array to look for radio emissions from the star KIC 8462852 -- that's the star I discussed last week that shows an unusual pattern of dimming and brightening. You can read the scientific paper here. (They've got to find a shorter name for that star. How about KIC MEE?). So what did the SETI investigators hear over the radio?

They heard nothing. Total radio silence. Now to be fair, KIC MEE is 1500 light years away, which is very, very far, so the power required for us to actually detect any radio signals would be in the range from a few billion megawatts to a hundred trillion megawatts. In comparison, our most powerful radio transmitter on Earth produces only ten million megawatts of power. But what's a few trillion megawatts to an alien civilization capable of planetary engineering? So the bottom line is, "Nothing to see here -- just move along." Time to cancel the alien invasion movie.

1 comment:

Kathy said...

Well, just because you can do something doesn't mean you'll do it. Consider airplanes. We could load all planes with full tanks of fuel for every trip, but that would cost a lot more money in fuel and engine wear and tear (a higher power setting being necessary to take off with a larger fuel load, which uses up more fuel). Therefore we don't do it.

I could greet every stranger in the street with a hug. But 1) that would be really weird, 2) I'm rather introverted and hugs make me uncomfrotable, and 3) there are an awful lot of strangers in the street. So I don't do it.

We could also communicate by encoding all information in emails, texts, IMs, etc. in Morse Code. But that would be inefficient and take more time. We don't do it.

Maybe any hypothetical aliens in KIC MEE (nice pun name, that) don't build radio transmitters any more powerful than they need for local communications. Maybe they use lasers for long range communications. Maybe they're xenophobic and take pains to shield their low-power communications to minimize the odds of being discovered (maybe the odd changes in light from the star are part of the radio/laser suppression shield!).

Maybe, and more likely, there are no live aliens at KIC MEE.

Also maybe some bright undergrad will find something about this star and win the Nobel in Physics in a few years. That would really be exciting.