The first mission to Mars that was to make a successful landing consisted of Viking 1 and Viking 2. It was an exciting mission with the orbiter picking landing spots for the lander to make a landing.
Viking Lander
Both spacecraft launched in 1975. They both made a successful landing and have lasted for about six years Voyager 1 failing when it was cut off by a faulty command sent by ground control which resulted in a loss of contact. Viking 2 also lasted about six years but failed due to a low battery.
Viking Orbiter
The lander’s main mission was to look for life. Life was assumed to be carbon-based and assumed therefore to metabolise simple organic compounds. Metabolism is the set of chemical reactions that, in life on Earth, allow organisms to maintain life. Of course there could be life elsewhere and they could use metabolism as well.
Viking Lander Two on Mars Surface
There were three biology experiments used to look at life on the surface.
- pyrolytic release experiment PR
- gas exchange experiment GEX
- labeled release experiment LR
The pyrolytic release experiment tested for life by exposing a soil sample to a simulated Martian atmosphere. The gases were then broken down by heat and then passed through a detector looking for carbon.
The gas exchange experiment was designed to test for life under two separate conditions. The first experiment assumed that life had been dormant for a long time and would be revitalized by exposure to moisture. In the second experiment the soil that was exposed before was now exposed to a rich organic broth containing amino acids vitamins and a number of other organic compounds called chicken soup by the inventor. A change in the gas mixture would indicate that some kind of organism was present.
The labelled release experiment was designed to detect carbon dioxide released by microorganisms. The microorganisms would release the carbon dioxide by their metabolic activity. Soil and another broth of chemicals was used and it was assumed that if any life was present it would metabolise the organic compounds in the broth and release a radioactive carbon dioxide which would be picked up by a Geiger counter.
So did these experiments detect life? Well, if they had it would be all over the news and would probably have saved NASA a lot of money as no other probes to search for life would have been needed. They may have sent probes to bring back microbes but this would have been much more interesting than the present rover missions and worth a little cash.
Unfortunately the tests revealed that Mars has a very chemically active surface as all the experiments yielded results. Unfortunately the results were and still are controversial and still open to interpretation at both ends of the scale. Some scientists still believe there is life and some do not.
All is not lost for the search for life on Mars though. The mars science labatory is due to go to Mars to continue the search for life. Unfortunately it has been put back by hardware and software problems and will launch in 2011.
It is slowly becoming a belief that life could exist in all sorts of environments and some other interesting areas to look are Europa and Titan but we will have to wait a while for missions to these moons.
It is fascinating these missions to explore Mars and other planets, I’d like to see in my lifetime development of manned missions to these planets using splendid spaceships.
http://www.youtube.com/watch?v=9ScAHXN_kAY
That’s another good idea. I wonder which one is the most efficient and cost-effective solution.
There already were manned Mars landings in 1976 – Vikings 1 and 2 landed Chuck Yeager and Bob Crippen on Mars.
When they returned, they found the Earth they knew was no more as their new commander-in-cheif was Jimmy Carter.