Thanks to our orbits , Earth and Mars make relatively close passing every 26 calendar month . Every now and then , there ’s a really close approach . In 2003 , for illustration , we fall at a length of 55.7 million km ( 34.6 million miles ) , the closest the two planets have been to each other in60,000 years .
In 1924 , the two planets made an approachalmost as close . During this time , astronomers and the US Government accept advantage of the situation and attempted to look for life on Mars .
This was n’t in the form of turning our optical telescopes towards the major planet to get a near look , but a search for potential radio signals being broadcast by exotic civilizationslivingon the Red Planet .
A telegram sent to all Navy stations in the US.Image credit: US National Archives
The idea may seem foreign from a modernistic perspective . We know now , thanks to serious telescopes , visiting distance probe , analysis of Mars ’s environment , androverswe have place to cast the planet , that the planet has no such civilizations . In the decades preceding the unaired glide slope , however , scientists were n’t all too absolved .
For a fourth dimension , uranologist suggested that there may be ocean on the planet . Then come the suggestion , bolster by maps made by astronomer Giovanni Schiaparelli , that Mars had a series of canals range across the planet . In 1894 , the populace became excited by the idea too , after astronomer Percival Lowell advise that Schiaparelli ’s observations showed canal that had been made by an alien civilization .
Lowell ended up using a significant amount of his own money to take photographs of these " canals"in 1907 , for him bear witness that the features were made by an alien coinage .
“ After the thaw of the south pivotal roof had puzzle well under way , canals began to make their appearance about it , ” Lowell allege at the time , as reported by theNew York Times .
“ It is a direct sequitur from this that the planet is at present the abode of intelligent constructive life , ” he added . “ I may say in this connexion that the hypothesis of suchlife upon Marswas in no way an a priori hypothesis on my part , but infer from the outcome of observation , and that my notice since have fully confirmed it . No other conjecture is consonant with all the facts here . ”
However , others were less positive , and the photographs he took ended up put up to the mind being disgrace .
After this , most uranologist were convinced the canals were an optical illusion , which was confirmed in 1964 when NASA probeMariner IVshowed there were no such feature on the planet . Nonetheless , there were still those who believed that lifetime could be on the satellite and that they could potentially transmit with it byradio .
Though the idea was not widespread , and evidence was begin to point to the planet not being inhabitable , as the two planet came near to each other in 1924 , humanity began its first tangible hunting for extraterrestrial radio signals .
The US Government asked the public to keep radio silence during thefirst five minutes of every hourfor " National Radio Silence solar day " as Mars and Earth made their near approach . During this time , astronomer kept an pinna ( and eyes ) on the planet , while the US Government request that all Navy outpost calm down their own radio receiver to listen out for any potential communicating from Martians .
It was affirmative , sure , and the resolution was predictable . No radio signal from Mars were picked up , as there was nobody there to broadcast them . It now seems likely that analog radio signals would be an unlikely elbow room for aliens to communicate , withother signalsmore likely . However , it was an interesting and exciting early attempt to discover advanced foreign coinage , endeavor which have continued to the present day , and may one 24-hour interval find in advance alien liveliness . That is , if they are outthere to be found at all .
