The idea of a radio signal to the moon may sound fantastic, but is easily within the range of possibility, says Dr. A. Hoyt Taylor, Chief of the Radio Division of the United States Naval Research Laboratories at Washington, who plans such an attempt in the near future.

“We have reason to expect a good chance of getting the signal back in a time interval of slightly less than three seconds,” said Dr. Taylor.

To be exact, a radio signal should be reflected back to earth in a time interval of 2.8 seconds, this being the necessary elapsed time for it to carry the 250,000 miles to the moon and return at its speed of 300,000 kilometers, or 186,000 miles per second.

The signal would be very weak, Dr. Taylor points out, but not impossible of detection with the present refinement of receiving instruments, provided no great absorption took place in interstellar space.

A high frequency wave will be used, as such a wave penetrates readily the earth’s atmosphere and probably goes far beyond. The frequency of the wave will range between 20,000 and 30,000 kilocycles. Twenty kilowats of power will be used, enough to furnish current for about forty flatirons.

The value of a radio signal to the moon lies in the confirmation of whether there is or not heavy absorption of waves in the upper levels of our own atmosphere. If successful it would indicate a reasonably good reflection coefficient at the surface of the moon—the power of the moon’s surface to act as a joint agent in the perfection of the signal.

The signal might have some bearing also on whether the moon has an atmosphere—something pretty much settled already by astronomical observation. It would also lead to the possibility of fairly accurate determination of wave velocity in free space, all of interest to science, either confirming existing theories or establishing new ones.