Our planet has some leakage of radio waves in space, from FM radio, television, military radars, and communications between the earth and our orbiting spacecraft. However, this leakage radiation is still quite weak and therefore difficult to see at distances from stars. at least with the radio technology we have. At present, our attempts to communicate with other civilizations are involve to receive messages, but not to send them ourselves.
However, some scientists believe that it is inconsistent to look for beacons of other civilizations without announcing our presence in a similar way. So should we regular try to send easily decrypted messages into space? Some scientists warn that our civilization is too immature and defenseless to report to us at this early stage in our development. The decision whether or not to send into space turns out to be an interesting reflection on how we feel about ourselves and our place in the universe.
Discussions about transmission raise the question of who should speak for planet earth. Today anyone and everyone can send radio signals, and many companies, religious groups, and governments do. It would be a humble move for the same organizations to use or build large radio telescopes. and start deliberate transmissions that are much stronger than the signals emanating from Earth today. And when we intercept a signal from an alien civilization, the problem of reaction arises.
Who should make the decision as to whether, when and how humanity announces itself? The cosmos? Is there freedom of expression when it comes to sending radio messages to other civilizations? Do all nations on earth have to agree before we send out a signal strong enough that it has a serious chance of being received in the distance of the stars? Deciding on such questions can be a test of whether there is intelligent life on earth or not.
Whether or not we are finally the only intelligent species in our part of the galaxy, our exploration of the cosmos will certainly continue. An important part of this exploration will continue to be the search for biomarkers from inhabited planets that have not spawned technological creatures that send out radio message signal. After all, living things like butterflies and dolphins may never build radio antennas, but we love to share our planet with them and would be happy to find their counterparts on other worlds.
Whether or not there is life exists elsewhere is just one of the unsolved problems of astronomy. A humble appreciation of how much we have yet to learn about the universe is one of the fundamental hallmarks of science. However, this shouldn’t stop us from excited about how much we’ve already discovered and curious about what else we will discover in the years to come.
The Ideas of Astronomy Progress Report ends here, but we hope your interest in the universe does not. We hope you will keep abreast of advances in astronomy through the media and online, or attend an occasional public lecture by a local scientist. Can you even imagine the amazing things future research projects about the universe and our connection to it will reveal?