Historical RTG performance data through 2023

Radioisotope thermoelectric generators (RTG) are the only technology
currently available that can provide reliable and consistent electrical
power for decades while isolated in extreme environments. RTGs have been,
and will continue to be, a critical enabling component in some of
humankind's most impressive feats of space exploration in the past
(e.g. Cassini), present (e.g. Voyager), and future (e.g. Dragonfly). Power
produced by an RTG will slowly decrease over time due to decay of the
radioisotope fuel and degradation of the materials within the generator.
With over 60 years of history, the technology of RTGs has evolved from
producing only a few electrical watts (e.g. SNAP-3B ~3 W) to nearing a
kilowatt of total mission power (e.g. Cassini beginning-of-mission 887 W).
They also evolved from systems that were only designed to last a few years
into systems that are now exploring interstellar space 46 years after
launch. Obviously, understanding how the performance of these systems
changes over their lifetime is of very high interest to anyone planning a
future space exploration mission. This dataset presents all of the power
and performance information that is available for all spaceborne RTGs that
have been flown by NASA and the US Department of Defense through
mid-to-late 2023. Some performance data that has not previously been
published is also provided here, including the full lifetime for Galileo
and Pioneer 11, as well as a near complete lifetime for Pioneer 10. While
all of the available performance data for RTGs is presented here, it
should be noted that the context of each mission and RTG design is
extremely important in understanding RTG behavior. It is not possible to
provide enough context to fully appreciate the behavior of all 29 RTG
space missions in a dataset publication, so users are highly encouraged to
find the appropriate context in Chapter 8 of the book, The Technology of
Discovery: Radioisotope Thermoelectric Generators and Thermoelectric
Technologies for Space Exploration (ISBN: 9781119811367).