I have the means to place watermelon sized transmitters anywhere within our solar system. I try to fake first contact as smartly as possible.

How would earth's observatories go about verifying my attempt at communication as truly alien and not a hoax? (lets assume that any communication originating from inside the solar system is believed to be a hoax)

Do I as the hoaxer have to resort to burst transmissions, or can I send a steady stream, but as if I were lightyears away.


2 Answers 2


There are few points to check that come to my mind:

  • origin of the signal 1: whatever emitted that signal is in the same direction.
  • origin of the signal 2: if the signal is coming from somewhere along the ecliptic plane, it would be seen as a very lucky coincidence, too lucky to be credible
  • origin of the signal 3: if more than 2 observatories detect the signal, they can in principle triangulate its source
  • features of the signal: power, frequency might spoil your attempt
  • language: how you encode the message will also tell something about you. Again, an "alien" speaking Cherokee or exactly mimicking the Arecibo message would be too much luck to be credible

Bounce your signal off of a remote system.

People have been bouncing radio off of objects in our system for a while now.


It was not until the close of World War II, however, that techniques specifically intended for the purpose of bouncing radar waves off the moon to demonstrate their potential use in defense, communication, and radar astronomy were developed. The first successful attempt was carried out at Fort Monmouth, New Jersey on January 10, 1946 by a group code-named Project Diana, headed by John H. DeWitt.[3]

People have bounced radio off of lots of other things in the ensuing 70 years. But not an exoplanet. You will be the first to do that. You use your space melons to bounce a message off of the exoplanet(s) in Proxima Centauri b. You need to aim carefully. Carefully I said! It is 4 light years away so hopefully you have a paying gig to occupy you in the meantime.

You can use a continuous message which will bounce back and be received as a continuous message, 8 years later. Note that if the orbital path of your melons puts Earth between a melon and Proxima Centauri b it will expose what is going on because the signal will hit earth on its way out.


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