Ever since humans evolved, efforts have been taken to explore the uncharted, leading to many discoveries. From exploring deep inside the earth to the great beyond, technology has opened its doors to such adventures. With time, space travel has advanced so much that astronauts and scientists are on the quest for ETs, Jadoos’ and Gimornicas. Movies like Galaxy, Interstellar and The Martian have displayed a glimpse on space travel.
With NASA coming up with a three stage plan to take humans to Mars, manned missions might soon become a reality. The first stage includes research projects taking place aboard the ISS (International Space Station) that can result in the possibility for humans to stay in space for prolonged periods of time while cutting down the possibility of health complications. The second stage is called the “Proving ground”, which is basically a quick trip to space that can shorten the period of travel to space. Scientists have been working on the SLS (Space Launch System) along with the Orion Spacecraft which can help us go farther into space. The third stage is “Earth Independent stage” wherein life can be established outside Earth making Mars as Earth’s new neighbour.
SLS is regarded as the world’s most powerful rocket for interplanetary travel and is being built in Marshall Space Flight Center in Huntsville, Alabama. Its ultimate purpose is to take humans to Mars one day. NASA’s article on SLS dated Sept 22, 2015 states that “On the program side, SLS recently completed its critical design review at Marshall. The in-depth review – the first in almost 40 years for a NASA exploration class vehicle – provides a final look at the design and development of the integrated rocket before full-scale fabrication begins.”. “We’ve picked the right vehicle for the journey to Mars,” said Garry Lyles, chief engineer for the SLS Program Office at the Marshall Center.
The Exploration Mission-I (EM-I) involving the SLS and a crew of astronauts is scheduled for launch on September 2018 which will mark the start of NASA’s mission to take humans to space by 2030s. The EM-I will complete its first mission with a duration of 3 weeks in space and is supposed to land on earth using parachutes.
The challenges of space travel starts along with take-off. The speed required to escape Earth’s gravitational attraction (aka Escape velocity) is achieved by shooting up in speeds exceeding 25000 mph, which is rather expensive. It costed nearly $200 million just to launch the Mars Curiosity Rover. Propulsion yet is another aspect to be focused on. The larger the mass, more is the force it takes and since rocket is heavy, higher capacity, liquid propellants are used. Chemical propellants such as kerosene can be used but they burn up in a matter of minutes and are not ideal for long missions. Most commonly used propellants are nuclear and plasma propellants.
Once the spacecraft enters space, Space debris pose a major challenge. Movies such as “Gravity” picturized the impact of space debris on the space station. This problem is dealt with the use of Whipple Shields- layers of metal and Kevlar that can protect against bitsy pieces but not against debris such as a satellite. Navigation in Space is done by Deep Space Network which includes a collection of antenna arrays in Australia, California and Spain. It is the only navigation tool for space. As more missions take flight, the network gets more congested and hence it is difficult to navigate spacecrafts that have gone farther. Scientists have been developing a system similar to that of GPS as in Earth called the DPS (Deep-space Positioning System).
We have had a glimpse of farming in space in the movie “The Martian” wherein, the stranded astronaut harvests potatoes in space. It is fascinating to know that a group of scientists cultivated lettuce in space in the ISS. As it comes with a lot of challenges, the scientists are working to develop a genetically modified plum tree which is 2 feet tall. They have also come up with water recycling systems in space stations to lower the energy toll.
Space travel seems very fascinating. Movies portray astronauts floating around the space shuttle with a heavy suit going easy on their diet, but that is far from the reality. Space travel causes long term health complications to astronauts such as loss of bone density and muscle injury. In order to prevent this, just like people on Earth, astronauts undergo 2 hours of workout in space everyday in the gym, including but not limited to treadmill exercises, to which the astronauts are strapped by bungee cords. In space, astronauts are subjected to a loss of their immune function making them more vulnerable to pathogenic infections.
What makes Earth unique is its atmosphere which has an ozone layer, but since Earth is the only planet we know of that contains an ozone layer, the major threat for astronauts in other planets is the UV-radiation which can mutate DNA and cause cancer. Exploration has always been the spirit of mankind. Since space travel poses a significant factor of harm to human beings, robots have been developed to explore further into space.
A holiday to space might soon become a reality. And soon enough, “What a small world!” might change to “What a small universe!”.