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Submission + - Scientists Seek To Reinstate Pluto As A Planet - And Many More

Rei writes: After several years of publicly complaining about the "bullshit" decision at the IAU redefining what comprises a planet, New Horizons programme head Alan Stern and fellow planetary geologists have put forth a new definition which they seek to make official, basing planethood on hydrostatic equilibrium. Under this definition, in addition to Ceres, Pluto and other Kuiper Belt objects, large moons like Titan and Europa, as well as our own moon, would also become planets; "planet" would be a physical term, while "moon" would be an orbital term, and hence one can have a planetary moon, as well as planets that orbit other stars or no star at all (both prohibited under the current definition).

The paper points out that planetary geologists already refer to such bodies as planets, citing examples such as a paper about Titan: “A planet-wide detached haze layer occurs between 300-350 km above the surface; the visible limb of the planet, where the vertical haze optical depth is 0.1, is about 220 km above the surface”

Comment Re: Great idea... But there is a problem... (Score 1) 301

They didn't die after a few minutes - they lasted for 1-2 hours. And they didn't cost a billion dollars, they were built on the cheap. The Soviets launched almost all of their Venus missions in pairs because they considered it likely that something would blow up or fail at some point along the way - not a rare situation, a number of their Venus missions never even left Earth orbit, and some didn't even get that far ;). But of missions that actually got to Venus, they had great success, and even had one mission "rescued" by Venus (they designed it to parachute down, but the parachute broke - but the atmosphere slowed the fall so much that it survived the impact anyway).

For exploring Venus, if you're wanting PR, the Vega approach is the right one - aerobots, optionally paired with sondes. Aerial vehicles can fly for long periods of time studying the planet, and there's a number of exciting missions related to this being worked on (just waiting for funding). As for surface lifespans, they don't have to be limited. There's work on probes designed to "run hot" so that they don't need any (or only minimal) cooling, and there's also work on probes designed to lift off (bellows balloon) to a cooler layer of the atmosphere (to have any length of time to examine / process samples, cool down, etc) before re-descending any number of times. If you're only talking something with a ~2 hour lifespan on the surface and nothing else, you're talking something cheap, Discovery or at most New Frontiers class - not Flagship.

The main thing that's held everything back is that NASA almost never funds anything related to Venus. The last dedicated NASA mission to Venus (not counting flybies to other destinations that used Venus as a gravitational assist) was the Magellan probe, nearly three decades ago. And that came a decade after the previous NASA mission to Venus. Easiest planet to get to, and they almost never fund missions to study it. It's embarrassing.

Comment Re:Echo-chamber fake news (Score 2) 394

There were a lot of contributing factors, but yes, this sadly was one. The Thiokol engineers were against launch, but they failed to make a sufficient case as to why exactly they felt the O-rings were unsafe (there actually was a Thiokol document showing that not only was O-ring failure high at low temperatures but that the second O-ring ceased to be redundant - but they didn't have the document available to them). The Shuttle program managers were getting mad at them for insisting on delays due to the low temperatures without being able to back it up (one of them said something along the lines of "My god, Thiokol - when do you want me to launch, April?") and eventually the Thiokol management dropped their objections (even though the engineers were still strongly against launch). The engineers all gathered round to watch the launch on TV, thinking it was going to explode on the pad. When it lifted off they all breathed a sigh of relief, only to have it dashed during the explosion.

Comment Re:Echo-chamber fake news (Score 5, Informative) 394

Really, I have to give them credit where credit is due: by repeatedly pointing out errors (however trivial) out of the tens of thousands of news stories that are published every day, they've managed to get their supporters to the point where they'll trust a new story on www.siteiveneverheardofbefore.com/newishstuff/hillaryclintonpedophilering.html more than they will an actual newspaper. It's a real masterstroke in terms of controlling the narrative. "Anything negative you hear about me, it's fake, because there exist cases where newspapers have made errors, and we've selectively presented you only with those cases to create a narrative for you that newspapers are packed full of fakery." Not just newspapers - fact checkers, peer-reviewed articles, even official government statistics - all fake, because they've been presented with every case people can get their hands of of error, without the balancing context of the 10000x more that wasn't in error.

In the words of XKCD: "Dear God, I would like to file a bug report". ;)

It's the same thing that contributed to the Challenger explosion. They had a nice clean graph in front of them that plotted O-ring failures vs. temperature. There was no clear trend visible on the graph. The problem was that they omitted the successes, the cases where there were no O-ring failures. Here's what it looked like with that added in. All of the sudden there's a very clear trend of failure increasing at low temperatures - in fact, every low temperature launch had had O-ring failures, while very few high-temperature launches had. By being selective in what data you present (accidentally in that case, on purpose in the present case), you can get people to believe precisely the opposite of what is true.

Comment Re: Great idea... But there is a problem... (Score 1) 301

Anyone who can say "only 6000 m/s" with a straight face when talking about post-launch maneuvers has never worked with rocket mass budgets. ;) For a single stage, 6000 m/s with a 340s isp and 0.08 inert mass ratio is an over 10:1 scaling factor (aka, for every 10 kg you launch to LEO you get 1kg payload to your destination). Just 3000 m/s is a nearly 3:1 ratio.

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