NASA is celebrating 60 years of nuclear power in space

NASA is celebrating the 60 years of nuclear power in space. On June 29, 1961, the first nuclear-powered satellite was launched. Transit-IV-A was an experimental navigation satellite. The power source was a radioisotope-powered generator. Its main designer was the Laboratory of Applied Physics at Johns Hopkins University in Cape Canaveral. And NASA has since conducted more than 25 missions with the nuclear power system.

60 years of nuclear power in space

The SNAP-3B radioisotope generator installed in the Transit IV-A space satellite produced 2.7 W of electricity. This is approximately the amount to power an LED bulb. However, the satellite broke the record for the duration of the mission. Since 1966, the satellite has circled the Earth more than 25,000 times. And on May 1964, it was the oldest operating satellite in the space. Among other things, the satellite also confirmed that the Earth’s equator is elliptical.

Radioisotope energy systems use thermocouples to convert heat from the decay of plutonium-238 into electricity. Articles are one of two practical ways to provide a long-term source of electricity in space. Other options are solar panels. But solar energy becomes less efficient if the spacecraft travels further from the Sun. The efficiency is also limited by the local conditions of the environment in which it operates.

In general, radioisotope energy systems are reliable and efficient, says Ms. June Zakrajsek, manager of NASA’s Radioisotope Power Systems Program at the Glenn Research Center.

“They operate continuously over long-duration space missions regardless of sunlight, temperature, charged particle radiation, or surface conditions like thick clouds or dust. They’ve allowed us to explore from the Sun to Pluto and beyond,” she said.

Plutonium-238 used as fuel in NASA systems is manufactured with the support of the US Department of Energy (US DOE). The isotope is produced by irradiating neptunium-237. It is currently manufactured by Oak Ridge National Laboratory in cooperation with Idaho and Los Alamos National Laboratories.

Next missions with a nuclear power source

Radioactive energy systems also powered the Lunar Surface Experiment Package. It is a set of geophysical instruments. Their design is designed to monitor the environment of each Apollo landing site for at least one year after the astronauts have departed. So do the Pioneer, Viking, Voyager, Galileo, Ulysses, Cassini and New Horizons space missions.

The Perseverance rover landed on Mars in February 2021. It is powered by a multimission radioisotope thermoelectric generator (MMRTG) using the Pu-238 radioisotope energy system.

Another NASA mission with plans to use the MMRTG is the Dragonfly spacecraft, which is scheduled to launch in 2027. Dragonfly is part of the New Frontiers program. It is a so-called “octocopter” that examines and collects samples on Saturn’s moon Titan. The nuclear propulsion provides the power to charge the landing module battery as well as the heat to keep its instruments and electronics running.

Among other things, NASA is also working with the US DOE and other industries to develop nuclear power systems that will allow human presence on the moon’s surface and ultimately human missions to Mars. Finally we believe that we will humiliate 60 years of nuclear energy in space several times.

Source: After 60 Years, Nuclear Power for Spaceflight is Still Tried and True