Since the early 1970’s the mysterious Red Planet has been closely examined by rovers and space probes, which have sent back invaluable information. Mars at large is a unique and different place compared to Earth, with the thin atmosphere that conjures winds and storms many times stronger than what we experience and the signs of liquid water in the past sparks curiosity in many astronomers.
The exploration of Mars there has been many discussions within space exploration institutions to send a manned-mission to Mars. Although media may portray Mars as the ideal destination the trip to the Martian soil, assuming both planets are properly positioned it would take roughly six months with the current rocket technology at our disposal to span the 54.5 million kilometers which separates Earth from Mars. There are many proposed methods to reach Mars, however currently the most energy efficient is the Hohmann transfer orbit, which uses the spacecrafts own velocity to escape out of Earth’s gravity and then decelerates as it approaches Mars gravitational field.
Once in the larger orbit of Mars, the spacecraft will begin aerobraking which has been previously successful in other missions. Aerobraking is used when the spacecraft first enters the orbit of Mars in an elongated elliptical orbit when can be circularizes (achieves the desired orbit, i.e orbit trim) by passing through the upper atmosphere many times to slow down. Depending on the atmosphere, a single rotation may be enough to slow down the spacecraft to the desired speed.
However, the heat caused through friction would require more heat shielding in turn adding more weight, also unpredictable turbulence effects and atmospheric conditions could be very difficult to predict. To reach the final orbit for Mars would take hundreds of passes (6 months) and would require some adjustment via thrusters at the final pass to remain in a stable orbit.
With these methods trip to Mars takes on average 300 days and with the transfer window open every two year, this makes manned mission to Mars rather difficult as the astronauts must wait a period of time to return back to Earth. However there are private companies that are researching better and more effective methods of rockets. Nuclear Thermal Propulsion (NTP) is a type of fuel which uses low enriched uranium which could theoretically half the journey time and could make it possible to execute mission even when the two planets are not aligned.
A faster Mars mission that takes 250 days for a return trip can be achieved with on-orbit staging (OOS). OOS is the combination of pre-positioning fuel supplies that are strategically placed in low-earth orbit (LEO) prior to the actual launch. This concept can be applied with many different types of rockets if not all, as the only variables are the number of assets in LEO. It is possible with modern technology to enable these methods, and with the combination with proposed NTP as the fuel source; the journey to Mars may not seem as difficult as once perceived.
Aerocapture, is similar to aerobraking but only undergoes one rotation. The drag generated would slow down the craft and would require a very small amount of fuel to decelerate, this would allow a noticeable increase in the overall payload for future missions; a economical gain nevertheless. With better thermal protection, aerocapture can allow faster deceleration to other planets and moons.
These new techniques in space exploration can be utilised and perfected through shorter trips to the moon, as it would be far more economically viable. Also the establishment of a moon base could potentially assist future missions to Mars, as the gravity is significantly lower compared to Earth.
Greater scientific findings
With only our remotely controlled robots exploring the Martian soil, there has been a ever growing fascination on humans to step foot on the red planet and the heightened competition between private institutions and government space programs, it is estimated humans may reach Mars as early as 2030. These human explorers can conduct a wider range of scientific experiments that is impossible for robots to do. We know that Mars was once a planet which had a warm climate and liquid water on its surface for over a billion years, Earth only had one fifth of the time to develop with liquid water. So if we consider this, life could have possibly appeared on Mars at some time in the past, and if we humans can find fossils of past life on Mars it would be a unfathomable scientific discovery. Contrasting to this, if we do not find any signs of past life, it is reasonable to conclude that the formation of life is near impossible.
As humans we grow and can expand our knowledge when we are given a challenge, as humans have already been to the Moon, there would not be a need for innovation for space exploration. However, if challenging task such as Mars is the goal there would be a major advancement in the current technology we have access to today.
Space exploration is perhaps the most inspiring for us, as it encapsulates the efforts of the great minds of engineers and scientists for a greater cause. It would motivate millions to pursue a STEM related career and the intellectual gains from all nations would greatly benefit mankind, outweighing the overall cost of the space program. Additionally, Mars is the first step towards a multi planet species, by utilising newer rocket technologies, interplanetary travel could become very common in the near future.
Mars contains many different elements and raw materials that are useful for the expansion of Mars colonise. These materials can be gathered to construct vehicles, buildings, and rockets, without needing to rely on Earth to send supplies. Metals that are both rare and valuable on Earth are abundant on Mars, Deuterium is five times more abundant which is the fuel used for nuclear fusion. This would easily spark commercial interest to manufacture and mine these minerals on Mars. Also, with the gravity on Mars being 2.4 times less than on Earth, the rockets would be able to carry a greater supply when exporting to Earth.