Russia is planning to launch a nuclear-powered spacecraft to Jupiter

Russia plans to launch a nuclear-powered spacecraft to the moon, Venus and Jupiter. Roscosmos announced Saturday that its "space tug," a term for a spacecraft that transports astronauts or equipment from one orbit to another, is scheduled to launch in 2030.

The spacecraft's energy module, called Zeus, is designed to generate enough power to propel heavy objects through deep space. It is essentially a mobile nuclear power plant.

Some countries see similar technologies as a way to shorten space travel. Currently, spacecraft rely on solar energy or gravity for acceleration. But that means astronauts could spend more than three years making round-trip visits to Mars.

NASA estimates that a nuclear-powered spacecraft could shave a year off the timeline.

The U.S. hopes to build a nuclear power plant on the moon — a 10-kilowatt reactor and a lunar lander — as early as 2027 — but, so far, NASA has sent only one nuclear reactor into space in 1965. Other spacecraft, like the Mars Curiosity and Perseverance rovers, are also nuclear powered, but they don't use reactors.

Meanwhile, Russia has placed more than 30 reactors in space. According to Russian state news agency Sputnik, its Zeus module will advance these efforts by propelling itself from planet to planet using a 500-kilowatt nuclear reactor.

The mission plan calls for the spacecraft to first approach the moon and then toward Venus, where it can use Earth's gravity to steer toward its final destination, Jupiter. This will help save propellant.

The entire mission will last 50 months (a little over four years), said Alexander Bloshenko, executive director of long-term programs and science at Roscosmos. In a speech in Moscow on Saturday, Blosshenko said Roscosmos and the Russian Academy of Sciences are still working to calculate the trajectory of the flight, as well as the weight it can carry.

The mission could ultimately be a precursor to a new frontier of Russian spaceflight: Sputnik reports that Russia is designing a space station using the same nuclear-powered technology.

Nuclear power has advantages over space solar

Most spacecraft get their energy from several sources: the sun, batteries, or unstable atoms called radioisotopes.

For example, NASA's Juno spacecraft on Jupiter uses solar panels to generate electricity. Solar energy can also be used to charge batteries in spacecraft, but as spacecraft get farther from the sun, the energy's effectiveness decreases. In other cases, lithium batteries can help themselves with shorter tasks. For example, the Huygens probe briefly touched down on Saturn's moon Titan in 2005 using batteries.

NASA's twin Voyager spacecraft use radioactive isotopes (sometimes called "nuclear batteries") to survive the harsh environments of extrasolar and interstellar space, but that's not the same as bringing nuclear reactors onboard.

Nuclear reactors have several advantages: They can survive in the shady regions of the solar system without the need for sunlight. They are also reliable over a long period of time - the Zeus nuclear reactors are designed to last 10 to 12 years. Plus, they could propel spacecraft to other planets in less time.

But nuclear power also faces challenges. Only certain types of fuel, such as highly enriched uranium, can withstand the reactor's extremely high temperatures -- and may not be safe to use. In December, the United States banned the use of highly enriched uranium to propel objects into space, provided that other nuclear fuels or non-nuclear power sources could be used for missions.

Russian engineers began developing the Zeus module in 2010, with the goal of sending it to orbit within 20 years. They are on schedule to achieve this.

Sputnik reported that engineers began building and testing prototypes in 2018. Roscosmos also signed a contract worth 4.2 billion rubles ($57.5 million) last year for preliminary designs by the St. Petersburg-based design firm Arsenal.

The technology could aid Russia's efforts to develop a new space station by 2025. The BBC reported last month that Russia plans to cut ties with the International Space Station (shared with the US, Japan, Europe and Canada) in 2025.

Russia launched the International Space Station in 1998 in partnership with the United States. However, Russian Deputy Prime Minister Yury Borisov told Russian state television last month that conditions on the ISS "leave a lot to be desired". In fact, the station has recently experienced an air leak and a breakdown of the oxygen supply system.

NASA has cleared the International Space Station to fly until at least 2028, but the agency is likely to deorbit its orbit in the next 10 to 15 years.