Peaceful atom for distant space missions

Soviet and now Russian rocket scientists have been working on nuclear rocket engines for more than 50 years already. Similar developments have been conducted by their colleagues in the US. There are two types of nuclear rocket engines.



by Sergei Mizerkin
Moscow (Voice of Russia) Apr 16, 2012


According to Russia's Nuclear Agency (Rosatom) the nuclear power and propulsion installation of the megawatt-class is to be built by 2017. The assembly will start already next year, first units of the installation. The development and construction of the nuclear installation will cost more than $247 million.

In the very beginning of the space era it was clear that it was impossible to launch space mission far from Earth using traditional chemical engines. The liquid and solid fuel powered engines, which are used now, have low technical and economic indicators, Alexander Zheleznyakov, academician with the Tsiolkovski Space Academy says.

"By now we have used almost all the potential of the chemical engines. It takes a very long time to accomplish a space mission to distant planets. Such missions are launched quite seldom and only relatively light and small spacecrafts can be used for such missions. The creation of nuclear rocket engine will enable us to significantly broaden our studies of the Solar system and may be also our possibilities to send missions to distant stars."

Soviet and now Russian rocket scientists have been working on nuclear rocket engines for more than 50 years already. Similar developments have been conducted by their colleagues in the US. There are two types of nuclear rocket engines.

The first type is impulse nuclear engine in which thrust is created by means of several blast of nuclear fuel. Tests proved that impulse nuclear engines have no prospects. The first prototypes of nuclear engines were built in the mid 1960s.

These were Soviet RD 0401 and American NERVA engines. In both engines the same principle was used: a working body (liquid hydrogen) was heated in nuclear reactor, and during the exhaustion thrust was created.

Though they were improved they were not used due to the high risk of nuclear reactor blast, which could be caused by overheating and due to high "exhaustion" of radioactivity. There were many accidents and emergency situations cased by satellites equipped with nuclear installations, head of the department of the Space Research Institute Yury Zaitsev says.

"We had a lot of accidents caused by these engines. Americans also had them. For example during the launch of the US Transit satellite - it burned above the Indian ocean and almost 1 kg of plutonium-238 was spread in the air. Later Soviet Kosmos 954 satellite fell on the territory of Canada contaminating the area of about 60,000 square meters."

But the new development solves the security issue. Spacecrafts will use ion electric reactive engines in which thrust is created by means of flow of ions, which are speeded up by an electric field. Nuclear reactor onboard of the station will fuel the engine and won't exhaust radioactive substances into the environment.
(My emphasis - Editor)

"Currently our space vehicles are using the energy generate by solar batteries. But they can operate only on the orbits close to Earth and can't be used for distant missions. That is why nuclear installations have a number of advantages in terms of capacity."

It is planned that nuclear energy installations will boost unmanned scientific spacecrafts which are sent to distant planets. In the future it may become possible to apply nuclear technology in spacecrafts which carry astronauts.

Source: Voice of Russia