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Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by cheeko1234 on Saturday January 19, 2019 @11:45AM (#18947822)
Dragonfly is such an amazing concept. A nuclear powered quadcopter!

http://dragonfly.jhuapl.edu/

>Unable to use solar power under Titan's hazy atmosphere, Dragonfly would use a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), like the durable Curiosity rover on Mars. Flight, data transmission, and most science operations would be planned during Titan's daytime hours (eight Earth days), giving the rotorcraft plenty of time during the Titan night to recharge.

Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by Isamu on Saturday January 19, 2019 @01:15PM (#18948306)
An octocopter, from the renderings.

They call it a dual-quadcopter. That may indicate that the configuration is for control redundancy, as well as increased lift and compactness.

Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by xtagon on Saturday January 19, 2019 @04:24PM (#18949271)
Interesting, I've never heard it referred to as "dual-quadcopter". It's a common configuration in the model aircraft hobby where it's referred to as "X8" octocopter. I supposed "X8" doesn't really describe their renderings though, since the airframe doesn't really look like an X.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by Latteland on Saturday January 19, 2019 @05:32PM (#18949635)
How about a smallish wheeled rover, with temporary battery pack, powered by the nuclear battery? Guess that would be greatly limiting the power of the main device to fly. At first I was thinking you could try for a solar powered rover, but it's much farther than mars, and you pointed out the atmosphere is blocking.

I feel so lucky to live in this grand age of exploration - where computer power, materials science and advanced engineering enable us to visit our solar system.

Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by bakery2k on Sunday January 20, 2019 @05:01AM (#18952251)
Does an RTG count as "nuclear power"?
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by ianai on Saturday January 19, 2019 @01:09PM (#18948272)
There’s got to be a way to do that here. Ie replacing oil power generation with nuclear - say for the largest container ships.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by reaperducer on Saturday January 19, 2019 @01:39PM (#18948426)
It's already being done. Since 1955 in submarines. Since 1959 in ice breakers. Since 1962 in commercial shipping.

https://en.wikipedia.org/wiki/Nuclear_marine_propulsion

Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by kolinko on Saturday January 19, 2019 @04:17PM (#18949231)
I wonder - why don't they use it for container ships and so on? I would imagine fuel savings there, and lower pollution would be immense.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by Armisael16 on Saturday January 19, 2019 @04:34PM (#18949327)
Well, it does result in enriched nuclear material floating all over the ocean, ripe for the taking by pirates or nation-states that we'd rather not have access.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by russdill on Saturday January 19, 2019 @07:17PM (#18950120)
Hopefully one day we'll see fusion powered container ships.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by ianai on Saturday January 19, 2019 @08:47PM (#18950431)
So you use the same naval threat that we already use to deter idiots from our nuclear powered vessels.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by nradov on Saturday January 19, 2019 @11:54PM (#18951207)
Pirates still seize large merchant ships in Asian and African waters on a monthly basis. There are only a few hundred surface vessels capable of effective anti-piracy patrols worldwide from all navies and coast guards; they can't be everywhere at once.
Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by dredmorbius on Monday January 21, 2019 @01:41PM (#18962423)
It's been done, commercially. It's proved noneconomic and technically problematic. Even without economic constraints, the US Navy reserves nuclear propulsion for carriers and submarines. It used to operate nuclear cruisers, but no longer does.

Several commercial nuclear powered ships were built, the Savannah by the US, and single ships by both Germany, the Otto Hahn, and Japan, Mutsu. All proved uneconomical, the Mutsu had major technical issues, and were either scrapped or converted to conventional fossil propulsion.

Among the more pressing problems is the size and loss rate of the civillian cargo fleet. From the United Nations Council on Trade and Development's Review of Maritime Transport: 2014. Total fleet size 47,601 registered ships, totaling 1.68 million deadweight tons. By type and deadweight tonnage:

* Container: 12.8%

* Dry Bulk: 42.9%

* General Cargo: 12.8%

* Oil Tanker: 28.5%

* Other: 11.2%

And those sink. With surprising frequency. From from "Monsterwellen", by Donovan Hohn in Outside magazine:

This is one reason merchant seafaring is still, by some accounts, the world's second-most-dangerous occupation, after commercial fishing. According to Imperial College London, 200 supertankers and container ships have sunk in the past two decades due to weather. Wolfgang Rosenthal, a scientist at the European Space Agency, which studies sea conditions via satellite, estimates that two "large ships" sink every week on average. Most of these, he says, "simply get put down to bad weather.'

See: https://old.reddit.com/r/dredmorbius/comments/3c52ll/shippin...

Re:NASA May Decide This Year to Land a Drone on Saturn's Moo... by nradov on Sunday January 20, 2019 @12:27AM (#18951345)
Sure we can do it. Use nuclear plants on land to provide power for the synthesis of carbon neutral artificial liquid hydrocarbon fuels, then burn that in ship engines.

Installing nuclear plants in modern civilian ships is a non-starter for safety, security, and cost reasons.