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Questions tagged [rtg]

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RTG is a Radio-isotope Thermo-electric Generator. It uses the heat generated by the decay of a radioactive material to generate power. Often the heat as well, to hold off the cold temperatures in space or other planets.

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Are RTG-powered spacecraft restricted to only some launch vehicles? [duplicate]

This answer by PearsonArtPhoto mentions for spacecraft powered by an RTG there's "only a single rocket that can launch them (Atlas rockets)". Of course that probably doesn't apply to non-US launches, ...
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How do Stirling radioisotope generators maintain a temperature differential in a vacuum?

I was reading the wikipedia page on RTGs and happened to stumble upon the section about efficiency. There were three methods that seemed to rely on direct conversion of thermal energy into electrical ...
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Mass ratio of solar-electric versus radioisotope thermo-electric power for propulsion; beyond how many AU do RTGs win?

Solar-electric propulsion has been used several times now in deep space missions. This question explores the scalability in comparison to Radioisotope thermoelectric generation or other nuclear-based ...
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How (and when) was the RTG in the lunar modules installed?

In this answer, it is explained that the space probes RTG's are not installed until a couple days before launch because of the heat those things generate. Now I'm curious about the Apollo RTGs. From ...
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Can Dragonfly make it to one of Titan's Lakes?

Dragonfly is a drone set to land on Titan in the mid 2030s. As I've read, Saturn - and thus, Titan - won't be in the right orbital position at the time to allow for direct contact with the drone if it ...
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What is the current status of Stirling engine-based radioisotope generator technology?

@Heopps' cool answer to the question Any proposed missions to explore the black liquid on Titan? Technical challenges? has an interesting line: ASRG generator was planned as compact energy source ...
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Why did Voyager have to shunt unused electrical power and radiate as heat?

Reading about Voyager in The oldest computer (not) on Earth I saw the image below, where is shown a science instrument calibration panel and shunt radiator. According to the November 1980 NASA News ...
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Why are planetary probe RTGs tilted at a jaunty angle?

This image from here: Does the Dragonfly project (quadcopters on Titan) envision attached RTG's or would they be static and revisited for charging? and this image show that the RTGs on these two ...
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Does the Dragonfly project (quadcopters on Titan) envision attached RTG's or would they be static and revisited for charging?

In this answer I link to the Phys.org article Researcher sets eyes on Saturn's largest moon which describes the Dragonfly project, a way to explore extended areas of Titan's surface difficult to probe ...
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How exactly does Curiosity's floating bus work, and how does it continue to operate when voltage drops from 11 to only 4 volts?

@Hobbes's answer calls attention to Emily Lakdawalla's book The Design and Engineering of Curiosity : How the Mars Rover Performs Its Job which led me to reading excerpts in several Planetary Society ...
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What delta-v per orbit would a spacecraft need to hover next to Saturn's rings?

In order to collect Saturn's ring particles for sample return to Earth, a spacecraft would need to share the orbit of this debris. If it is inclined it will have to pass through the rings twice each ...
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Radioisotope thermoelectric generator behavior on reentry

The RTG has become a major source of power in places where solar power just wont cut it. but there has always been an issue with sending them into space. if the launch fails, radiation comes raining ...
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How an americium-241 RTG would differ from one using plutonium-238?

@TomSpliker's great answer mentions that ESA might be looking at producing Radioisotope (powered) Thermoelectric Generators (RTGs) based on the radioisotope americium-241. 241Am is a "kinder and ...
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Which countries have built RTGs and used them in Earth orbit and/or beyond?

I know the US has; a few have even left the solar system, there's some on the Moon, one on Mars, and one inside Saturn, though now "extensively modified". Rosetta had to hibernate for 2.5 years for ...
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How much RTG fuel does China have?

Chang'e 3 is still operating, 3 years later, sending good science from its LUT (Lunar-based Ultraviolet Telescope) - running on RTG batteries. NASA is supposedly scrapping the bottom of the barrel ...
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501 views

Tritium as energy source for probes?

There's this ingenious little hack video: "How to make tritium nuclear battery at home". The idea is very simple: "tritium keychain lights" - tubes with tritium and luminophor - placed between solar ...
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If Curiosity had lights, could it drive or work in the evening?

If the Mars rover Curiosity had been equipped with lights, would it be able to drive or do other work in the evening? This could be some combination of LED headlights, wheel-lights, and/or a spotlight ...
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Why are RTGs different colors?

This is an image of the radioisotope thermoelectric generator (RTG) for Cassini: This one was for one left on the Moon: And this one is for the Multi-Mission RTG, used by Curiosity on Mars: One is ...
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What were the uses of the RTGs in the Apollo spacecrafts?

I was listening to the Plutonium episode of "the Elements" on the BBC, and between 07:00 and 08:30 they talked about uses of plutonium such as spacecraft power and heat. While the returning astronauts ...
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Does Curiosity pose a radiation hazard for would be colonists?

I understand Curiosity is powered by plutonium decay. I was wondering if that kind of battery leaks. If humans ever go to Mars, and they want to meet with Curiosity, would they need to take extra ...
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What's the total specific energy of RTG?

How many joules of electric energy can you draw out of an RTG battery over its lifetime - and what's the mass of that battery? (whole; shell, thermocouples, fuel and all.) (realizing, that the power ...
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Why wasn't an RTG used on the Juno spacecraft?

When I first heard about the Juno spacecraft, I was surprised that it would be using solar panels to generate power throughout the mission. Why wasn't a radioisotope thermoelectric generator (RTG) ...
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How does the launch risk for a plutonium RTG and a uranium fission reactor compare?

I was looking at this answer that talks about how a good alternative to Radioisotope Thermoelectric Generators would be fission reactors. It makes a number of good points, but in the comment thread ...
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Why was radio contact with Pioneer lost earlier than with Voyager?

Why was radio contact lost with the Pioneer probes much earlier than with the Voyager probes? The Voyagers were launched only 4 years after the Pioneers, yet the Voyagers are projected to last into ...
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Could radiated heat propel space-craft in outer space?

The comment chain on What is the feasibility of launching a probe to Sedna? indicates RTG thermocouples decay. With the passage of time the thermocouple may even have the ability to transduce an ...
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Could electricity propel Curiosity on Venus?

To-date the humans have dispatched surface missions to Mars Luna Venus Mars has a thin atmosphere. Luna lacks one. Venus has a soup-thick atmosphere. Landing a static craft on Venus is one thing. ...
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How would a satellite powered by RTG be terminated?

How will a satellite powered by RTG be terminated at the end of its life? Is there any set of rules to be followed? What's the general procedure?
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What happens to an RTG if the demand exceeds supply?

NASA writes to say As the electrical power becomes less and less, power loads on the spacecraft must be turned off in order to avoid having demand exceed supply. A lead battery would 'die' if ...
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Do nuclear batteries emit radioactive rays while in use by satellites and shuttles?

Nuclear batteries are very small in size. Hence they find application in satellites or shuttles as a replacement to solar batteries. They also use large amounts of energy released naturally by tiny ...
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How far from the Sun can solar power be used as a reliable energy source?

Space probes headed for the far reaches of our Solar System rely on radioisotope thermoelectric generators for power (Cassini–Huygens, Voyager 1, Voyager 2). Presumably this is because solar power ...
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How long will communication with the Voyager probes continue?

Voyager 1 and 2 are the most distant man made objects. How long will we be able to still communicate with them? What will be the first thing that prevents communication? RTG exhaustion? Signal ...
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How does the launch risk posed by plutonium compare to the launch risk posed by propellants?

For outer solar system exploration, virtually the only feasible power subsystem are Radioisotope thermoelectric generators (RTGs). These include plutonium, which may carry considerable risks (see ...
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Are there any safe-to-launch alternatives to RTG's for outer solar system exploration?

In the past two decades, NASA has launched at least three missions that use RTG's: Cassini Mars Science Laboratory New Horizons Those launches include plutonium, which is a reason for some to oppose ...