The major reason behind considering Mars as a planet for human colonization is the presence of atmosphere. Terraforming or transforming the atmosphere of Mars to suit human beings is one of the options considered by scientists. With the discovery of water on its surface, colonization on Mars can become a reality in the near future.
The approximate time required to reach Mars is 9 months. Reducing the time spent in traveling is possible, however, not with the currently used chemical rockets. Instead, the space propulsion technology would be required. Use of constant-acceleration technologies is one more option. Ion drives and solar sails are the constant-acceleration technologies and their use can cut down traveling time to just a few weeks.
Mars is more suitable for human inhabitation than any other planet or even the Moon. There have been speculations about transforming or terraforming the prevalent conditions on Mars to suit human habitation. The idea has however, drawn flak from all over the world.
The atmosphere of Mars is not as thick/dense as that of the Earth. It means the ionizing radiation can enter the environment of Mars. More research needs to be undertaken to obtained detailed inputs about the Mars' atmosphere.
Communication between Mars and Earth
The NASA and European Space Agency (ESA) have placed communication satellites in the orbit of Mars. These satellites are the relay equipment used for communication. The communication delay between Mars and Earth (attributed to speed of light) ranges from 3 to 22 minutes. The possibility of setting up communication pathways by means of telephone lines, however, doesn't seem practical due to the time lag.
Creating a path to Mars for regular traveling is of utmost importance if we are thinking about colonizing this planet. Robotic systems that are currently being used should prove to be instrumental for traveling and also in carrying out further research. NASA's robotic mission, the 'Mars Exploration Rovers' has sent two unmanned rovers, 'Spirit' and 'Opportunity' to this planet till date. The robotic systems have reduced transportation cost and proved to be useful in finding ice and water on its surface. Establishing the bases for landing spacecraft and setting up permanent bases on the surface of Mars can be done with the help of such space vehicles.
Locations for Establishing Colonies
Different regions of Mars are being studied for the purpose of habitation. Owing to the presence of ice caps, polar regions are looked upon as possible areas for setting up colonies. Natural caves are found in equatorial regions of the planet and there is a possibility of water reserves being present in these caves. As the surface of Mars is not fully explored, scientists are awaiting more useful information. The topography of Mars may be varied and diverse than what has been predicted. Let us now turn our attention towards other aspects of colonizing Mars.
Advocating Colonization of Mars
'Mars Society', an organization founded by Robert Zubrin, promotes and advocates the colonization of Mars. It was established in 1998 and does the work of educating people and governments about benefits of space exploration and colonization of Mars.
'Mars Drive' is another group that supports space exploration and colonization of Mars. Founded in 2005, this group has spread out in Europe, North America and Australia.
Areas of Concern
The atmosphere of Mars is very thin. Its density is about 1% of that of earth; this poses problems for landing of heavy spaceships on the surface of Mars. Thus, a specially designed braking and landing system is needed. The currently used robotic systems for landing on Moon and Mars cannot be used in the case of Mars. Effects of Martian gravity on human health have not been studied yet. So, it is difficult to predict whether Mars can support human life in the long-term. The dust storms which affect Mars form another area of concern for the mission of colonization. These storms reduce solar radiations that reach the surface of this planet.
Colonizing the planet Mars is challenging, both from the economical and technological point of view. However, efforts are being taken to resolve the issues and clear all hurdles. Let's hope that a human colony on Mars comes into reality in the near future.