Recently, president Barack Obama announced his administration’s commitment to the exploration of our solar system. One of the targets divulged was a mission to Mars. Set for around 2030.
For the fans of science fiction, the exploration and colonization of our solar system and beyond is the holy grail. Countless are the Science Fiction writers who already ventured and predicted how far the exploration of space can take us.
Isaac Asimov wrote books about a a hyperdrive propulsion that would be pivotal in permitting the expansion of mankind into a vast Galactic Empire. The technology, much similar to what is seen in Star Wars, allows the ship to jump into the hyperspace where the universe is compressed in tiny dimensions. The traveler moves inside the hyperspace to later jumps out into regular space and arrive at the desired destination.
Star Trek creator imagined the Warp Drive or Warp Engines. The Warp Drive generated the Warp Field in which space was bent (or warped) and origin and destination became “closer”. Thanks to that, the Enterprise could cross vast amounts of space and “boldly go where no one has gone before”. Interesting enough, many scientists are developing the theoretical basis in which, one day, warp drives could be constructed.
Other authors like Stephen Baxter and Carl Sagan went more scientifically close to what is known to us and employed wormholes as a way of transportation. These holes are, so far, a theoretical concept. They are ruptures in the fabric of space-time (since Einstein, space and time are seen as one aspect of nature as opposed to previous believe that space and time were separated entities) and form tunnels by connecting themselves with other wormholes. By traveling through these wormhole tunnels a person can cross vast amounts of space in almost no time. Both Baxter and Sagan believe that an sufficiently advanced civilization could construct a network of wormholes with the sole purpose of exploring the universe.
Arthur C. Clarke somewhat used the same concept of wormholes in his tetralogy “Space Odyssey”. Nonetheless, in his novels, humans were only capable of using nuclear powered rockets to cross the solar system at a high velocity. Such propulsion system is being currently developed in many places. In the near future it may become our gateway to new places. Even though this technology makes for faster ships, if compared to chemical fueled rockets employed today, a trip to another world would still be a matter of months or years .
Science Fiction writers focus a lot on artifices to reduce the duration of the trip. This is, when it comes to space travel, the most visible issue to most of us. However, there are some other aspects of the endeavor that deserve consideration.
Exploration is expensive. The Apollo program costed $25.4 billion. In today’s values that represents $170 billion. Long range (further than the moon) manned missions demand big spaceships that can only be built in space. Only the construction budget will tend to be enormous. To lift into orbit one pound costs $10’000 (For alternatives to this specific issue see article about space elevator).
Finally, when it comes to money, many country leaders are reluctant in spending fortunes because these missions take years to be planned and executed. Investment done by them will bear fruits only in a future and different administration.
In science fiction, ships have all comforts of modern life. The gravity is generated artificially, oxygen is abundant and a dampening force field protects the crew from harmful radiation. NASA, today, does not have these amazing gadgets available to equip the space ships.
On a long term mission astronauts can expect to be years away from home. During this time they will suffer the effects of micro gravity, will be exposed to radiation, may become ill or even have an accident. Because these are life threatening situations, some advocate in favor of lower cost and risk-free robotic missions.
An hyperdrive or a warp drive are great because they shorten the duration of any trip. Sadly our current technology relies on slow chemical rockets. Voyages to the planets of our solar system under this technology take an awful lot of time.
The Voyager I and II took decades to reach the outer solar system where they encountered Uranus and Neptune. Because of the duration of the missions, manned spacecraft will need systems to recycle water & oxygen. Furthermore, they will have to carry enough fuel, oxygen, food, water and medical supplies. The longer the mission, the bigger the “luggage”. An alternative to that is have part of the needed supplies and other tools could be sent ahead of the astronauts. Before returning home, the crew would replenish their stocks with the material sent ahead. The difficulty with this approach is that we need to ensure that the supplies and tools will resist the hardships of the trip, will not be destroyed during landing or during the time they wait for the crew to arrive. The landing has also to be precisely planned and mapped. Astronauts would not have enough resources to execute a planet wide search.
THE MECHANICS OF THE SKY
To sail across the solar system, timing is essential. On earth, origin and destination don’t move because they are “fixed” on the surface of our planet. With celestial bodies, this is different because both origin and destination move (or orbit). The flight path has to consider the speed of the space ship and the movements of the planets in space allowing a perfect rendezvous.
WHAT ABOUT TRAVELING TO THE STARS?
With our current technology, a trip to the closest star system (Alpha Centauri who is 25.6 trillion miles far from us) will take 165’000 years. If we travel quite close to the speed of light (around 188’000 miles per second), a one way trip still would need 4 years.
Because of the distances involved, interstellar travel requires a significant improvement in our current propulsion systems (or the invention of a faster than light drive) and a significant amount of planning. Number one, the mission can not simply arrive in this brand new place and star looking for planets. Somehow the flight path needs to be decided prior to departure. The mission must be equipped with every element that ensures survival of the crew, allows for research and even plan protocols in case we find life or intelligent life.
We all certainly hope that somewhere in our future we can leave the confines of our planet and start venturing into what Shakespeare called “undiscovered countries”. The universe has the capacity to teach us and humble us. Unlike so many centuries ago when Columbus and Magellan set sail to expand the boundaries of our own planet. The future explorers will have a much more difficult and yet much more fascinating task. These ambassadors for mankind will explore, learn, take risks and enrich our species.
TO KNOW MORE...