The story of space exploration starts on October 4, 1957 with the first orbital flight of Sputnik 1. But, beyond this historical success, an unknown factor remains: will man be able to survive in space? It is necessary to wait for the flight of Gagarine in 1961, then the many following manned missions, to answer this question. The space adventure is launched... Like any process, it knows cycles of progress or stagnation, false tracks, readjustments, and spectacular successes.
It is a time of economy, in all the meanings of the word. Paradoxically, public opinion claims sometimes for less expensive projects, sometimes for programs more ambitious than the “simple” fact of “turning around” on low orbits.
Space industry, however, is in expansion : pushed by military applications, it is also, in the field of communication, a major actor of the emerging information society. Space is a mirror turned towards the Earth: “space beacons” offer systems to navigate with an extreme precision thanks to the GPS, and satellites provide a full range of instruments for the observation of the Earth and its environment. With quite modest budgets, scientific programs are pursued : space telescopes scan the deep sky, and automatic probes fly through the solar system to reach comets, study the Sun, and explore the surface of Mars or Titan. All these new images of the Earth and remote stars contribute to change our conscientiousness of the world, maybe in a less spectacular way than, in its time, the Apollo program, but with the same force.
The mission must be economic, offer to the future crew perfect conditions of security - thus of redundancy of equipments -, while respecting the cycles of rotations of the Earth and Mars around the Sun ...
The adopted solution lasts a little more than three years. In fact, the first vessel sent towards the red planet does not carry passengers yet. This automatic machine is sent on a low energy trajectory, for a voyage of 8 to 9 months.
Arrived near Mars, it separates in two modules: one of them remains in orbit, it will be the future return vehicle for the astronauts; the second one land on the surface of the planet, and begins a chemical work of synthesis - exploiting atmospheric and in-depth water resources - in order to distil sufficient quantities of liquid oxygen and hydrogen. This fuel will be used by the crew for his return back to Martian orbit.
At this time, the manned vessel leaves the terrestrial orbit. Its trajectory, a little more expensive in energy, reduces the duration of the flight to 6 months. The crew must remain 18 months on Mars in order to find another favorable shooting window, and will be back to Earth after another 6 months flight. The full manned mission lasted about two years and a half. The interest of this program is to launch, together with astronauts, another automatic vessel identical to the first one, in order to initiate a second cycle of flights, and thus of new inhabited missions. It is also, because of the redundancy of the vessels, an additional security for the twelve astronauts of the crew.
The Moon is not forgotten. Compared to the distance of Mars, the Moon seems to come closer to the Earth. After a few decades, Man is back on his natural satellite. But the Moon is also the symbolic meeting point for two of the most important technological and human adventures of the XXième century: its conquest in 1969, and the development of Internet since the 90’s.
Automatic rovers have already been used to discover the beautiful landscapes of Mars. However, because of the distance of Mars, it would be forever impossible to control them in real-time.It is not the case anymore on the Moon : many of the future “virtual pilots” train themselves on simulators reproducing the shift of a little more than one second necessary for a command, transmitted at the speed of the light, to reach the robot.
The Moon is rediscovered thanks to Internet… Space exploration is not reserved anymore to a few specialists, but anyone can bring his skill, his curiosity, and his talent, to photograph a crescent of Earth above the Serenity Sea, visit deep craters, or explore mysterious fractures ...
Beyond the Moon, space robotics is improving. The two keywords are "micro" and "nano": the increasing miniaturization of electronics, and progresses in artificial intelligence, lead to new generations of probes and automatic vehicles. One is reminded that robots are both allies and rivals of man in space. Is there any interest for man to carry out dangerous tasks, when they could be done, perfectly and safely, by a machine? As a former spationaut said, the presence of man in space is only necessary when he brings what is the proper of man : his perception of the world, and his consciousness…
Automatic probes cross the solar system, and, for the first time, the surface of Pluto is photographed. Observation robots are orbiting around all major planets, with a very particular interest - with Mars - for Jupiter, Saturn, and their satellites. Astronomers discover that a comet emerging from the Kuiper’s belt should, in a few years, ineluctably collide Uranus: a mission is quickly programmed to study closely the phenomenon. Except when they are turned towards the Earth, scientific satellites move away from “traditional” saturated terrestrial orbits. It is first envisaged to send the new space telescope on a Lagrange point, between the Earth and the Moon. But scientists abandon this idea: too stable, they concentrate micro dust interfering with observations. It is a lot more interesting to satellise the space telescope around the Moon, waiting for the next generation of instrument built on the surface of the satellite, in a polar crater, eternally protected from the sunlight.
Foundations, and non-profit associations, benefit from the decreasing costs of space fights to carry out original projects. Soon, the Earth-Moon race of solar sails is finally organized : During a commercial flight, a little part of the payload is offered to launch in space three capsules of a few tens of kilogram. Each of them, once in orbit, unfolds a large solar sail able to use the photonic pressure of the sunlight. During several months, the solar sails race is followed by millions of spectators on Earth : a trophy is won by the first sail able to photograph the hidden face of the Moon. Encouraged by this success, organizers of this Earth-Moon race decide to renew the competition every four years, during the summer Olympic Games.
Private actors are interested by space tourism. They do not have yet the infrastructure to develop their own orbital launchers, but use little rocket planes able to fly during a few minutes or a few hours, under excellent conditions of comfort and security, on suborbital trajectories sufficient – for their privileged passengers - to contemplate the spectacular curves of the Earth. This new industry is based on serious marketing studies showing the existence of a real market, with a promising potential of development.
The space adventure is pursued on Earth too, in research laboratories, where two strategic priorities are closely related to space. The first one concern energy: if fossil resources appear to by sufficient to respond to demand for several decades – a short-term future anyway - their production costs increase continuously and ineluctably. Hydrogen technology, also strategic in space, appears as a major stake. Hydrogen fuel cells for example, resulting from Apollo’s research and development programs, are of a great interest for automobile industry. Solar energy, in same time, could find original solutions in space : giant hyperstructures of kilometers long, built in geostationary orbits, could capture the solar energy and send it to the Earth with microwaves beams.
The second priority responds to one of the major preoccupation of this early XXIst century: the protection of the terrestrial environment, and the study of its climate evolution. Constellations of satellites are dedicated to the observation of the Earth, the oceans, the atmosphere. This harvest of information collected from space has a goal: to change behaviors, mentalities, policies, on the surface of a small planet we never cease to rediscover the beauty, and the fragility.
A new generation of space shuttle is developed, exclusively used for passengers transport. Like any launchers, it uses liquid hydrogen and oxygen, whose combustion produces in the atmosphere a water vapor inoffensive for environment. This space plane is a gigantic flying wing, a wingspan larger than a jumbojet, from which, at very high altitude, a small shuttle takes off to reach low orbits, then return back to the Earth on the runway of any airport. The Earth has now an economic and sustainable system to reach the sky.
After the conquest of the Moon, for several decades, all the inhabited missions are concentrated on Low Earth Orbits, only a few hundred kilometers above the sea-level. During this period, the "technology of weightlessness" is improved, the capacity of man to accomplish very long stays in space is tested, and modular space stations are built.
One of the key elements of space programs is the Shuttle, an extraordinary space plane designed to minimize the cost of the "ticket to space” during multiple missions. It carries out nearly one hundred twenty flights in twenty-five years. However, this number is far from the initial objective of the program, and one cannot forget the tragic destruction of two of the six spacecrafts of its fleet.
In the early 2000’s, interests are focused back on a dreaming destination: the planet Mars. First of all, it is a middle/long term objective able to coordinate, and make more readable than in the past, the whole space program.
The debate is about flight strategy : is it preferable to plan a direct mission towards the red planet, or return beforehand on the Moon as a the first step for the voyage?
Soon, a new generation of launchers appears. The space shuttle is abandoned, and replaced by simpler - and more reliable – systems, distinguishing freight cargos from little manned spacecrafts. The public is surprised by this return, after a few decades, of spacecrafts similar, in their form and their principle, to Apollo’s designs. Space capsules, however, have never been abandoned : neither by Russia with Soyuz, nor China sending taïkonautes in space, in the same way , since 2003.
