It looks like mankind is only a few decades or even just years away from reaching Mars. But the truth is that even though interplanetary travel would be possible in the near future, it entails a hefty price.

SpaceX CEO Elon Musk is determined to send the first humans to Mars by 2024. President Barack Obama, in support of NASA, recently said that Americans will "take the giant leap" to Mars by 2030 and plane maker and commercial space flight company Boeing, says it may be able to send the first humans to Mars instead of SpaceX.

However, despite the organizations' adamant and aggressive intent to send humans to Mars, the discussion on how much money is needed to turn these goals into reality are very rarely discussed, aside from the initial $10 billion ticket to Mars price tag per head as revealed by SpaceX CEO Elon Musk.

This is the concern of astrophysicist Neil deGrasse. It appears that the price to pay for sending people to Mars will serve as a big obstacle in making the Martian dream a reality. But it looks like more companies private and government-owned, are willing to invest in "interplanetary" missions.

In his former works, deGrasse revealed three reasons why mankind still pursue a very expensive ambition, to become a multiplanetary species. The reasons include the praise of deity or royalty, war and the search for economic return, according to a report by Forbes.

In an essay written by President Obama, the most powerful leader in the world revealed that NASA and its partner organizations including private companies could achieve space explorations programs. This can also mean that deep space explorations and interplanetary travel can be executed when they have a deeper pocket and more resources at hand.

"Getting to Mars will require continued cooperation between government and private innovators, and we're already well on our way. Within the next two years, private companies will for the first time send astronauts to the International Space Station," President Obama said in an essay he wrote published by CNN.

Experts are also calling on to the next president of the United States to also invest in space science and deep space explorations because in the end, it will generate income for the government and its partners and in the long run, will be beneficial for mankind in general.

The investors, including the government, should always remember that space exploration is not easy and it is not cheap so in whatever program or project they pursue aside from Mars, the price to pay will also amount to a hefty sum.