Vladimir Shlyomin

I

n July specialists from leading Russian scientific research institutes focused on aerospace and nuclear industry related issues are expected to announce a project of a round-trip manned exploration to Mars. This announcement is supposed to be made within the framework of discussions initiated by the International Scientific Technical Center (ISTC). According to Vladimir Smetannikov, the chief designer of nuclear space propulsion systems, this project will be mainly based on the lates Russian nuclear technologies.

Academician Nikolai Ponomarev-Stepnoy, a vice president of RNTs Kurtchatov Institute scientific research center, estimates the prospect of a manned exploration to Mars as "a dream that is to come true in the cause of time". According to Mr. Ponomorev-Stepnoy this exploration is as inevitable as the discovery of America once was. However, interplanetary missions are impossible without nuclear space propulsion systems required to boost space vehicles and provide them with power. Such propulsion systems can hardly be designed without the rich experience of Russian space system designers who have been world leaders in development of nuclear technologies for space missions. Technological achievements of the Soviet era have still provided for unique solutions to aerospace technical challenges.

To take a space vehicle to Mars the vehicle’s propulsion unit should have a thrust of 15 to 20 MWt. According to analysis made by specialist from M.V. Khrunitchev State Space Scientific Production Center compared to chemical fuel nuclear powered space propulsion systems could cut the flight time by 1.5 times. Thus, with a 7 ton thrust propulsion unit consisting of several nuclear powered engines on board, a flight to Mars would take no longer than 460 days.

Intensive scientific research and tests in this direction were started half a century ago. Dozens of Soviet enterprises and thousands of distinguished specialists have worked on the problem of practical use of nuclear power for space applications. As a result, specifically for space missions, a small capacity thermal emission nuclear core was designed to provide power supply for onboard equipment of earth satellite vehicles.

In the mid 1960s reliable positive data was obtained with regard to the prospectiveness of developing an effective nuclear powered space propulsion system with a thrust exceeding that developed by the most powerful chemical fuel rocket engines. To develop major engineering solutions and consider adequate construction materials for the nuclear reactor core a special test facility was built in the town of Semipalatinsk equipped with a test nuclear reactor, a ground-based prototype of that proposed to be installed on board a space vehicle. The reactor was started up in 1975. By 1988 the Semipalatinsk test center had accumulated data on the possibility of the practical use of nuclear power for space missions. Experimental and test results showed an ability of the nuclear powered propulsion unit` s fuel assembly to perform effectively during four thousand seconds under temperatures of up to 3100 Ê and at a specific power release rate of up to 33 kWt/cm3. Thus, a sound argument was obtained confirming the possibility of creating compact and high capacity sources of power both for propulsion units and reliable power supply for different objects in space. In the 1970s -1980s more than thirty space purpose nuclear reactors were designed and successfully used in space missions to generate power for onboard equipment by means of direct energy conversion.

Sure, to assemble interplanetary stations in orbit and to create a lunar base will call for new types of powerful rockets. Russian scientists are now working on a new super heavy three stage launcher capable of boosting into close orbit payloads of up to 100 tones. The first and the second stages of this launcher are supposed to use well-reputed a RD-170 and RD-180 liquid fuel rocket engines, with the third stage being supposedly equipped with RD-122 hydrogen-oxygen propulsion unit which has been tested within the framework of the Energy-Buran space program.

To deliver the space vehicle to a Mars orbit and to bring it back to Earth it is supposed to use a RD-0410 nuclear rocket propulsion unit developed by KB Khimavtomatika aerospace design bureau. This propulsion unit has already passed through a series of ground tests.

Moreover, to boost into an orbit space modules for the assembly of an interplanetary station one can use both existing Proton-M rocket engines and the respective Angara-family means of delivery. As early as 2007 the first rockets of the Proton –M series may start placing into close orbits payloads of up to 25 tones while Angara -7 launchers will boost those of up to 41 tones.

"Today Russia has both an infrastructure required to start work on these projects and the requisite elements to organize manned interplanetary missions. I mean we have launchers, acceleration propulsion units, habitation modules, logistics modules and a space shuttle project, manned by six astronauts, to be placed into orbit by Angara-3 launchers. This shuttle will be capable of both aerodynamic and ballistic descent," says Anatoly Kuzin, deputy general director of M.V. Khrunitchev State Space Scientific Production Center. Mr. Kuzin said that there was a nuclear rocket propulsion unit prototype which was practically ready for use and featured performances required for the implementation of these projects.

Russian vice president Alexei Zhukov states that the Russian government offers its support to hi-tech projects. According to Mr. Zhukov these hi-tech projects include those in the field of nuclear and aerospace industries. The vice president emphasizes that a great deal is currently happening in terms of cooperation with foreign partners: "On our part we try to support these contacts and foresee a big future for international cooperation in this field."

It remains for us to add that the circle of countries interested in this challenge is getting wider. Besides the USA and Russia currently nuclear space technologies are also being developed by European countries and China, with competition for leading positions and orders in this lucrative technical sphere getting tougher. Hopefully, for a while Russia has a good chance to maintain its lead position in this latest stage of space exploration.