The dangers of space exploration are many. The excitement will still draw humans to learn more about outer space. Wouldn’t it be nice if humankind could indulge its passion for space exploration in a safe and secure manner. There is a new set of science projects in the works which may just allow humans to explore space by proxy.

There has been considerable progress in the field of robotics. The new generation of robots are smarter, more efficient and more flexible than the initial attempts a decade or so ago. Giant strides have been made in the programming of robots. There is a good chance of teaching a robot how to learn for itself.

An ongoing project has taught a robot to access the internet and learn how to do tasks that it is not programmed for. This kind of instant tutorial may eventually help develop Artificial Intelligence in the robot. The sensitivity of the robotic arm has also been improved drastically.

The robotic arm can now handle soft and fragile items with far greater ability and dexterity than before. It is able to handle complicated electrical repairs in outer space that would usually necessitate a space walk for a human astronaut. So with all these improvements thanks to different robotics based science projects it may soon not be necessary for the human beings to leave earth to explore space.

The call of the great unknown has always beckoned humankind. Now with all the terrestrial areas having been mapped the boundaries of the unknown have got pushed into outer space. The ongoing science project which is called space exploration is a dangerous business indeed.

Lives are at stake in every mission that seeks to send humans out into the hostile reaches of outer space. The point was driven home very effectively when the Space Shuttle Columbia crashed killing all seven crew members on board on February 1, 2003. The tragedy served an important purpose in reminding all of us of the frailty of human life and the strength of human spirit.

As the 106 metric ton weighing Space Shuttle Columbia re entered the over Texas there was anticipation at the completion of a mission well done. However shortly after the controlled, destructive reentry of the shuttle pieces of the space vehicle broke up. This happened when the left wing shielding during launch allowed hot gases to enter the wing structure of the shuttle.

The disintegration of the Space Shuttle Columbia saw pieces of debris scattering all over northern Texas and eastern Louisiana. The media covered the event extensively and it was humbling to learn that the best laid plans could really go astray. Not that it affected the science projects dedicated to exploring space as new missions still are being planned each day.

In the previous blog post we read about some of the satellites that have re entered the Earth’s atmosphere. It may seem like a waste of the science project for it to end up in little broken down fragments all over the Earth. However what we are trying to ascertain is if the fiery end of these monuments of science is dangerous to the denizens of earth.

Saturn S-II-13 was not exactly a satellite but the second stage used on the massive Saturn V rocket, famous for launching Apollo astronauts to the moon. This 49 metric ton projectile had a free fall, uncontrolled re entry into the atmosphere of the Earth on January 11, 1975 over the Atlantic Ocean. There were no known casualties.

The Cosmos 1402 was a nuclear spy satellite. The 4 metric ton satellite fell to the earth on January 23, 1983 in an uncontrolled re entry. It broke up over the Indian Ocean. Satellite nuclear reactors are usually jettisoned to a safe parking orbit when the satellites re enter the atmosphere but this did not happen in this case.

Mars 96 was a Russian Mars probe that was meant to send four probes to Mars. The science project mission was a disaster and the satellite fell to earth in an uncontrolled re entry on November 17, 1996. The 7 metric ton weight of the satellite was demolished as it entered over South America. Parts of the fragmented satellite fell in Bolivia, Chile, and the Pacific Ocean. No parts of the spacecraft, including its 200 grams of plutonium-238 fuel was recovered.

The International Space Station or ISS is probably the largest artificial satellite of the earth right now. There are plans to have the ISS crash in to the Pacific ocean soon. Many people are worried about the big satellite’s re entry into the Earth’s atmosphere. Do they have cause to?

Not if you go by historic data on falling satellites. The Skylab re entered the atmosphere over the South West Australian region on July 11, 1979. It was a 79 metric ton weighing satellite which had an uncontrolled re entry and managed not to kill or injure anyone when it fell burning to Earth.

Salyut 7 was a Russian satellite which re entered the atmosphere on February 7, 1991. The entry point into the atmosphere was over Capitán Bermúdez, Argentina. It weighed 40 metric tons and yes the residents in a small town in Argentina did get some shower of debris. But the large satellite was an uncontrolled re entry which again did not represent a danger to human life.

The Russian Mir satellite was the first of the controlled re entries of a satellite in to the Earth’s atmosphere. This science project is interesting as despite wanting to save the 120 metric ton satellite it broke down into fragments over the Pacific Ocean. It re entered the atmosphere over Fiji in the South Pacific Ocean on March 23, 2001.

The rather tragic end of a grand science project such as a space satellite is the re entry which practically demolishes it. We heard a lot of noise about the recent satellite crash to earth. People were searing that parts of it fell near a small town in Canada, while Forbes (dot) com insisted that the satellite fell in the Pacific ocean and no where near Canada.

The natural preoccupation that we have with space includes the fascination of something akin to the “sky falling on our heads” rather like Chicken Little. Of course in that story it really was a piece of an alien ship. Wonder what the Canadian would have to say if that happened.

Any how, to get back to the point in question. Is there any real danger when we hear of satellites falling to the earth? Not much. As with any science project you have a number of people working out the data of the orbit and crash landing site well before the satellite is allowed to re enter the atmosphere.

However as with all science projects there is also the element of risk. Something that has not been thought up of can often go wrong and often does. Still there no grave physical danger in most such cases as most of the large satellites that have fallen to earth have managed to do so without any major incident.