‘X’ Marks a Curious Corner on Pluto’s Icy Plains | Hacker News Reader

‘X’ Marks a Curious Corner on Pluto’s Icy Plains

nasa.gov

79 pointsjapaget43 comments

Reminding us once again how cool it would be if we could "easily" send robotic probes to go and stay on various solar system "places of interest."

Something I hope that comes out of SpaceX's reusability of boosters is a way to put a mission package into orbit, then launch a boost unit with the necessary engine and fuel that then docks with it, and then puts it into the necessary orbit to get to its destination.

This...but. We need to gain the ability to make more of these things (or equivalent): https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

We're doing that. Production of Pu238 (the RTG isotope) is being restarted.

http://www.universetoday.com/100875/u-s-to-restart-plutonium...

That's exciting news! Thank you so much for sharing that.

Pluto in particular would be a problem, though, because it is a) very small, and b) very far away. In order to get there in a realistic time, your probe has to be going _very quickly_; in order to stay in Pluto orbit, the probe has to be going _very slowly_.

So, unfortunately, to stay in Pluto orbit, either you carry a lot of fuel with you to slow down (which makes launch incredibly difficult, because you need more fuel to accelerate the fuel you need to slow down, and then you need more fuel to accelerate _that_ fuel, and so on), or you wait a long time to get there.

The bigger, closer planets and planetoids, though, will see a lot more exploration as the cost of launch decreases.

Or you send some self replicating stuff on the moon, build some factories and solar panels, and build and launch robots from there. We have the technology to do this right now if we are willing to put the money. And if we polish the moon we could beam excess energy to earth.

What do you mean by "polish the moon"?

Chrome the moon?

I can only assume it means creating a large, vigorously reflective surface. Not the whole moon, but presumably making a reflective, concave part large enough to send a focused beam of directed energy.

(NB: this doesn't sound like a good idea to me, or necessarily realistic, I'm just guessing that's what is meant.)

Cover it with solar cells.

Colonize it with Polish people, of course.

Just make sure to send the government up there first.

> Or you send some self replicating stuff on the moon [...] > We have the technology to do this right now

Do we? Self-replicating robots would be very exciting, even on Earth, but I thought we weren't close to being able to make them. Do you have a citation/link?

You have 3d printers that can print themselves. That is a cornerstone.

Everything except assembly, the motors, and the electronics. It's definitely getting closer but we don't have printers that can actually print themselves just yet.

FANUC factories.

2003:

http://money.cnn.com/magazines/business2/business2_archive/2...

2007 (?):

https://www.youtube.com/watch?v=-SREct28lJM

2010:

http://www.bloomberg.com/bw/magazine/content/10_49/b42060442...

2015:

http://www.wsj.com/articles/japanese-robot-maker-fanuc-revea... (put google in the referrer to avoid paywall)

They are just a industrial automation company. Why should they be able to build stuff on the moon?

>> to stay in Pluto orbit, either you carry a lot of fuel with you to slow down

Gravity assist can be used often used to speed up a spacecraft, but can also be used to slow it down.

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

In addition, atmospheric drag can also be used to slow down a spacecraft passing a planet.

While both of those statements are true, Pluto is too small and its atmosphere is too thin for either of those approaches to slow down a probe enough.

Generally the gravity assists act on other planets on the way to the destination. For example, Cassini got assists off of Venus twice, then Earth, then Jupiter on its way to Saturn.

Note: I'm no astrophysicist, and this is just back of the napkin math

Uranus is the physically closest planet to Pluto at the minimum distance of 11AU (about 1,64 billion km). Pluto's escape velocity is about 1,2 km/s (putting the orbital velocity at about 0,7 km/s). So a naive brake on Uranus would need to put the craft such that it brakes down to less than 1 km/s. 1,65 billion km at 1 km/s is about 52 years. Which seems to be a like letting off the gas in a car while going up a hill to break, but then getting to the top and still needing to go 50 miles to your destination. So something else needs to be in place other than just relying on gravity assists/braking.

This is an interesting study that could get 20kg into Pluto orbit. It uses gridded ion engines coupled to multiple Radioisotope Thermal Generators.

PDF: http://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-ISTS2004-Plut...

It'd be even cooler if we built some nuclear-engined robotic spacecraft and sent them to nearby star systems like Alpha Centauri. We really need much faster propulsion to do serious exploring; it took a decade to get New Horizons to Pluto, and that was the fastest spacecraft we've ever launched.

Safely getting that much nuclear material into orbit is tricky. What if the launch rocket fails and explodes in the atmosphere?

Ok, fine. We'll just stay on this planet and stop all space exploration because an accident may happen.

Besides, I'm pretty sure this has been addressed many times before. It's not that hard to secure nuclear material; we've dropped nukes in accidents before and they didn't detonate because they were so well-built. Even if you intentionally dispersed some nuclear fuel at high altitude, the concentration would be so low it wouldn't make a difference.

And what do you mean about "that much nuclear material" anyway? We safely launch tons of cargo all the time. How much nuclear material do you think it takes to power a rocket? Do you have any clue how little nuclear material is in a full-fledged bomb?

The nukes which were dropped were not attached to massive rocket engines that have a disturbing tendency of blowing up spectacularly >1% of the time.

Yes, they were just wrapped in large amounts of high explosive. Which sometimes exploded.

And don't forget about the hundreds of nuclear bombs deliberately exploded in the atmosphere last century.

"That much nuclear material" as in "enough to visit nearby star systems". Perhaps you've underestimated the literally astronomical distances involved, and how much power is required to get there in anything close to a reasonable time-frame. It would be required to accelerate at full speed for centuries, then turn around and decelerate for centuries more. It's easy to imagine that taking enough nuclear material to be able to cause a non-negligible nuclear disaster on a scale that meets or exceeds past nuclear disasters. Fukushima and Chernobyl weren't exactly trying to travel to another star system, after all.

Then again I might be completely wrong, but seeing as it's literally rocket science, I think you can forgive my ignorance and I can forgive your condescending tone.

I think the "snail" in the middle of the picture is more curious than the x. What is that?

> The darker patch at the center of the image is likely a dirty block of water ice “floating” in denser solid nitrogen, and which has been dragged to the edge of a convection cell.

I love that we (the public) are still getting regular updates about what scientists are finding from the Pluto flyby.

Some water ice farmer out late. :-)

It isn't really a capital 'X'. It looks more like the stylized, more wide than tall, X of a spaceX landing pad.

Compare with this:http://i.space.com/images/i/000/045/531/i02/spacex-rocket-la...

Looks to me like conditions ripe for life. Not necessarily life we're familiar with, mind. And maybe not necessarily clicking all of the check boxes of "Life", but structures far more interesting than dumb rocks.

Okay, as expected, Pluto is a very cold rock. No surprise.

What the heck is NASA looking for out there, some evidence of trash left by ET, a big, black, rectangular parallelepiped with some strange audio and electronic signals pointing to Jupiter? Don't think they will find it.

We have to expect that in the universe, both near and far, there are a lot of really cold rocks orbiting a lot of stars, "billions and billions". To get something "curious" on one of those will be really rare.

Want to see what one of the really rare ones looks like? Okay, three guesses, the first two don't count. Hint: Look at where you are standing.

IMHO, NASA needs to find some more important questions to ask.

Mars? Okay, if there is good reason to go to Mars, then, first, do a lot in robotics: Net, send robots that can build a colony, make rocket fuel from whatever is there on Mars, fuel a rocket, sent it back to earth successfully. Iterate several times. Build a bigger and bigger colony that is more and more capable. The colony should be really good, and safe for humans -- food, water, heat, comforts, safety, etc., and a rock solid, highly reliable, very well tested way home. Then test a lot more -- much, much more testing.

Then maybe send some humans.

gotta take pictures first, don't ya?

That's a 'couch explorer' way of doing it - explore as long as you sleep in your bed at the end of the adventure. There are very many people that would go without the need for a way home. And that would be a heck of a lot cheaper.

To do much on Mars, just must send a lot of robots. The robots have to be relatively autonomous if only because the time for radio communications is so long. Sending a lot of suicidal people is not so good. One reason is have a lot of dead people up there could in some respects corrupt the site under study.

Generally, if we are going to do much in exploration on rocks other than earth, then we need some good autonomous robots. So, we might as well get with building the robots.

For sending humans to Mars, we really will be very interested in getting them back safely. One way to have confidence that we can is what I outlined: Let robots do essentially all of the needed work first so that by the time humans go they are really just guests of the robots that have long since been very successful -- lots of trips back and forth with no mistake-ys.

Again, wrong about the part about getting back safely. Its ridiculous to assume we cant go to Mars until they have an entire space industry to launch vehicles. We can go decades earlier than that, just by establishing a colony.

Let's review some history for the moment. Back in the 19th century "egghead" scientists conducted numerous lines of research into several subjects which were at the time considered to be extremely esoteric, the essence of pure, "blue sky" research. Some examples from that century would be: electromagnetism, particle physics, quantum mechanics, and gas laws.

As it turned out, understanding such things lead to lots of innovations which had not been anticipated beforehand. Everything from electric motors and lightbulbs to micro-processors, cell phones, internal combustion engines, fertilizer, and AIDS drugs. Those innovations built on the back of once pure scientific research have resulted in billions of years of human lives lived that would not have been other wise, and billions of years of lives lived in improved conditions (due to more food, cleaner water, greater wealth, and so on), literally tens of trillions of dollars per year of added economic activity due to those innovations and quadrillions of dollars of added value and increased wealth to human civilization. All due to egghead scientists studying stuff just because they were curious.

What will be the next set of breakthroughs? Where will it come from? How much value will they add? We don't know, that's why we continue to sustain and support our curiosity across such broad ranges of subjects.

Not only might breakthroughs come from surprising directions, but I think the scientists have more than earned it. Not everything we do needs to have some tangible return-on-investment back to some concrete bottom line on Earth in the near term.

Sure, but you left out some crucial parts: "Often we find that a good question is more important than a good answer" - Richard Bellman. IMHO pictures of Pluto do not answer good questions.

Commonly, one of the most important steps in good research is good problem selection. IMHO, getting pictures of Pluto is not good problem selection.

Mars? It's closer in. There we might get some clues to the formation of the solar system. And we have a chance of setting up a base on Mars for astronomy or whatever. Pluto? As we have long known, it's really 'out there'.

Pluto? Wild guess: There is so little going on there, and it's so darned cold, that maybe we could use it as a source of a preserved record of some of the major events in the galaxy over the past 5 billion years or so Pluto has been going around out there. For this guess, maybe look at the justification NASA gave for the Pluto effort.

You seem to be missing it. Let me try to break it down again.

First off, plain and simple, we don't know what we don't know. So straightforward it's tautological. It makes sense to expand our knowledge in every direction possible.

This is the MO of a curious species. And curious species are vastly more successful than incurious ones. To paraphrase Randall Munroe, the legacies of incurious species are carefully discovered, studied, and remembered by curious ones. Curiosity is a survival trait.

Dedicating less than 4 parts per million of our country's enormous economic activity toward studying an important part of our stellar neighborhood seems a worthwhile entry in the activities column of a sufficiently curious people. Moreover, the return-on-investment on unbounded curiosity is so close to infinite that it's hard to view complaints about such comparatively tiny expenditures in regards to their practicality or short-term tangible returns as anything other than laughably myopic.

> It makes sense to expand our knowledge in every direction possible.

Not quite: Instead, for any amount of money, there are, or, as we start spending the money on research, soon will be, more candidate research projects than money. So we have to pick and choose our research projects.

IMHO we have better candidate research projects, including just in investigating the solar system, than getting fly-by pictures of Pluto.

Maybe NASA has some longer term ideas for research on Pluto where the recent pictures, and maybe also just the trip there, are just the beginning. Okay, land there, in a bunch of nitrogen snow. Take and analyze some samples and radio the data back to earth. Maybe get some data unique and valuable data on the formation of the solar system, maybe on some gamma ray bursts or super nova explosions, etc. Maybe. But just the pictures? IMHO, not so good.

kind of OT but, "Its surface is separated into cells or polygons 10 to 25 miles"

reminds me of glimmervoid: http://magiccards.info/mma/en/223.html

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