When Robert Heinlein wanted a title for his new work of fiction about a young man born and raised on Mars and now returned to Earth, he selected a quote from Exodus which addressed the Israelites living in the foreign land of others:
"I have been a stranger in a strange land."
In 2003 three probes from Earth were sent to land on the distant planet of Mars; two succeeded. Mankind has been fascinated with the Red planet since it appeared to be the only one in our solar system most likely to be habitable. The fascination goes back to the 19th century when astronomer Giovanni Sciaparelli reported in 1877 his observation of large channels (canali) on the planet.
A number of scientists in United States have long desired to someday send a manned mission to the distant planet wherein we will be as Heinlein's Stranger in a Strange Land. 
Science Fiction writers have been fascinated with Mars since fantastic fiction has been around. One early writer was Herbert George Wells who wrote about an invasion of Earth by Martians. In his book, the people of Mars are cruel destroying humans until they themselves are destroyed. Other later imagined a gentle and intelligent race of Martians. Ray Bradbury's works wherein he writes of Mars speaks about an ancient race from which we humans can learn much. His Martian Chronicles is the opposite of Wells' story. In Chronicles, mankind destroys much of the beauty of the planet in addition to the race that created the beauty.
Radio provided to a public interested in the mystery of Mars usually by offering adaptations of these great writers.
In 1898, Herbert George Wells published his fictional account of an invasion of the Earth by Martians called War of the Worlds. In 1938, sixty years later, Orson Welles, John Houseman and their Mercury Theater produced a dramatic retelling of the Wells' story called Invasion From Mars. 
The radio play was adapted from the book by Howard Koch, but Welles, in his usual dominant and brilliant way, made changes which reflected the times he lived in. Using techniques similar to the recent news reporting on the Munich Crisis and playing upon the tightly wound emotions of the country as the rest of the world seemed poised for war, the play came alive as if events of the invasion were really occuring. The result was that the broadcast scared the country some even into panic.
In the first clip, the then new technique of interrupting programs for bulletins is used initially by Welles to introduce a touch of realism. Imagine for a moment that it is 1938. You have heard over your radio recent crisis bulletins about the continuing war drums in Europe. You read daily in the paper the struggle to keep America out of war. At the same time, you might recall how only 20 years ago one of the most devastating wars in the history of America finally ended. It is within this context that Welles genius in his use of radio becomes evident.
This is followed by the end of another interruption seguing into a musical interlude as the network prepares to switch to another bulletin rather than return to the original musical program. Then we are returned to an on-the-spot report of something awry. Frank Readick, the reporter Carl Phillips, is entirely believeable as he acts his lines of a fictional story. The excitement in his voice and the increasing failure in the explanations of Professor Pierson (Orson Welles) increase the tension. Finally, near the end of the clip something seemingly horrific occurs but the reporter must stop his broadcasting and we are returned to a musical interlude only increasing othe listener's frustration.
Finally building to the ultimate suspense of realism it appears Martians have truly invaded the Earth, we hear an on the spot report very reminiscent of the then recent Hindenburg Disaster report. As something seemingly horrific is happening, the report is cut off abruptly leaving the listener wondering what is happening - something about rays of light causing people to burst into flames! In the listener's frustration, he is told that there appears to be other landings throughout the country. The Martians it seems have invaded and appear bent on destruction of human life.
Another look at the nature of Martian civilization comes from a radio play broadcast in 1948 on the thriller series Mysterious Traveler. The story is about a planned invasion of Earth by Martians. 
They have been landing throughout the world and infiltrating our societies in places of power preparing to conquer Earth at a specific time - Zero Hour. A scientist and a reporter discover the plans too late. The idea is so fantastic no one will believe them.
The idea of civilizations on other planets including Mars has always been considered the turf of the dreamer. That thinking is depicted near the beginning of the radio play when the professor explains to the reporter why he generally keeps a low profile on his thoughts about alien life. But in advancing the story the professor explains that man is so caught up in traveling to other planets that he forgets that other planets might try to invade us.
Later in the story concrete evidence is found that points to an alien existence. The professor finds a small cylinder with symbols never seen before and as the professor points out, he knows twelve languages and this one is definitely not from Earth! They are determined to get back to Washington (our nation's capital, where political power is based, was always considered the key city in the pre-space exporation days for stories dealing with aliens. Just look at any of the science fiction films of the fifties). To expedite their need to relay information, they stop by a house with the nearest telephone to call. But through the scientist's intuition, we begin to get a sense of foreboding. The musical bridges and the foreign sounding accents help greatly in establishing that sense.
The final part of the broadcast drives home the point that we should fear Mars because it might contain a dominant civilization that could conquer us.
After reading about the "death" march by the American Indians who had escaped from their reservations in the 19th century, scriptwriter Ernest Kinoy penned a Science Fiction tale for the NBC Series Dimension X (later re-created on X Minus One) in which Martians have been placed in reservations by conquering Earth men. Some of the Martians escape with the help of a mystical man called John. But soon the Martians are once again rounded up and some are killed in the uprising. Radio drama (some science fiction writers) from the early fifties began to take a more benevolent look at the planet Mars with man being the destructive one. Remember, this is after both the United States and the then Soviet Union have exploded Atomic Bombs. The Martians are depicted as victims of the recklessness of Earth men.
The theme of Martians as victims always seemed to contain some element of hope that man was not all bad. Within the stories there was usually a savior who tried to protect the Martians or preserve their history.
Ray Bradbury 
was an up and coming writer of Science Fiction and Fantasy whose writing matured in the fifties. Many of his science fiction stories centered around the planet Mars. Like Ernest Kinoy's Martian Death March he wrote about the planet and Martians as benevolent people who often were wronged by invading Earth men. In The Martian Chronicles he tells many different stories about the planet and its fictional people.
The book though a collection of individual stories was adapted in a shortened form for a Dimension X broadcast also titled The Martian Chronicles. The book was adapted by Ernest Kinoy into the radio play. In one segment we meet Ylla and her husband as they lazily live their lives on the planet Mars. Bradbury writes of a loving people who almost seem as Adam and Eve before the fall as we get a foreboding of the coming of earth men. As we here on Earth wonder about Mars, Ylla dreams about life on Earth. The coming invasion of mankind destroying Mars is the reverse of what people had read and heard before 1950. Bradbury has turned the tables on traditional science fiction about Mars.
In a later scene in the radio play (a different story in the book) we get a sense of what man has done to destroy the Martian civilization. This is seen through the eyes of another savior of sorts - an Earth man named Jeff Spender. Speaking of his fellow spacemen he says "Where's their sense of what's right? Their respect for what's happened here?"
Not all of Bradbury's stories about Mars show the Martians in such an elevated light. In Mars Is Heaven we get a more horrific picture of the Martians. However, even in that radio play the Martians' actions have a sense of justification. Earth men have intruded on their planet and they seem to be taking action to protect themselves. Yet they are not really threatened as they were in The Martian Chronicles. Are their actions truly necessary?
Near the beginning of the play we get a feeling that the arriving Earth men are operating on fear of the unknown. This does not sound like a friendly crew! A little later Dr. Horst, who is totally a creation of the scriptwriter, Ernest Kinoy, and not in the original story, becomes the conscience of the Earth men.
As the men look around they discover that the planet does not appear to be Mars, but Earth in 1928! They begin seeing their families, their supposedly dead parents or siblings. What is going on? Are they themselves dead? In heaven? Are they on Mars? Perhaps Mars is heaven?.
Soon the whole town comes out to greet the ship. Soon most of the crew seems enamoured of where they are and are beginning to forget their mission. Even Captain Black seems taken in. But soon it will all go wrong. The foreboding is told through the character of Dr. Horst. The play ends with Captain Black locked in his ship as probably the sole survivor anxiously trying to contact and warn Earth. In Bradbury's excellent storytelling the horror is through the error that the Earth men have made by letting their guard down. But the Martians we learn are only acting for their own protection against a more powerful force. As in The Martians Chronicle man is the bigger enemy.
As the coming months approach with man's desire to once more reach out to other planets, we wonder what we will find. Our science has advanced to a point that there are little surprises. But popular culture especially science fiction continues to capture our wonder at the unknown distant planets - especially our relationship with the "Red" planet.
The complete radio plays in mp3 format. Right click to download: