Friday, July 17, 2015

More on Pluto (if you're not already fed up with the Big Stories!)

The New Horizons photos of Pluto are, as all the quivering hype suggests, magnificent and truly thought-provoking. But, for us, maybe the thoughts are rather different from what most people seem to be thinking.

The first close-up is here, as given by NASA.

From the news description that we are referring to for convenience here, these are 'historic'. Of course, this may not sound like simple hype, but in fact even my yesterday's dinner napkin is 'historic', unique, and never to be repeated. Perhaps the headline's adjective should have been more like 'first' or 'unique' or something more measured than that.

The photo shows a rocky Plutoscape, with ice, or icy, mountains on the size range of the Rockies. Essentially all of these findings seem entirely within the range of what we know from extensive near-space exploration (Pluto is still near-space in this context). There are wet and cold or warmer or denser or gassier planets, there are various moons and other flying objects. Each is different, of course, just as each, say, watermelon or mountain range is different. But is there something more than more of the same here? More of the same just confirms what we basically already knew about space and the charivari flinging about in it.

To find something curious to report, it was said by one commenter that it is noteworthy that Pluto doesn't have pock marks indicating meteor hits. That might be somewhat different from the routine cataloguing of mountain heights and so on. If true it could be an important fact to explain: How could this planet not have been peppered with meteors like the others?

We are not astrophysicists so can only react to what the news media, quoting various physicists, are saying. The idea is that the 'hits' are occurring, but that the dynamics of Pluto is patching up the holes, so we don't see the remains. This would not be a unique physical process, but could tell us something about Pluto. We wonder about this. Look at these two NASA images, also from New Horizons.

On the top is Charon, the Plutonic moon (these are not to scale; Charon is much smaller even than tiny Pluto). If you look carefully, you'll see that it has what, to an amateur like us at least, looks like meteor-hit pock marks. And if you look at the bottom image, which is Pluto from just after the fly-by, so farther away and showing the whole once-a-planet, you'll see what seem to be pock marks on it as well.

At one point, the BBC quotes a scientist as saying "We have not found a single impact crater on this image. This means it must be a very young surface." Another quote is that Pluto has been "resurfaced by some geological process - such as volcanism - within the last 100 million years". But in the final image, or the latest that was released in the news stories, showing the whole once-a-planet, there is a crater identified, in the lower left part of the image, and we have also labeled the location of the close up (our first reproduced figure above), which shows that it is rather close to the area that is being said to have some particular crater-erasing geological dynamics.

So it is not clear what conclusion one should draw from these images. Are we now in an ad hoc, mode, where we will see specific processes invoked for each specific feature, rather than a more theoretically based unifying idea of the inner nature of Pluto? That could be interesting, if there will be evidence of geographically different regions, in the way that the Earth has seismically active regions, regions where moving plates intersect, and so on. Or will it just be guessing? How accurately can photographic images resolve such issues?

What real scientific news would be like
So the first looks at Pluto from up close, spectacular in their own way, aren't all that scientifically new or shockingly novel as the news blares indicate. If we found that Pluto was made entirely of copper, or contained formations of polycarbonate plastic, or was made of green cheese, then we would really be facing something truly new, something not already very well established in our theoretical cosmological repertoire. That would be something to energize the mind and drive us to explore an unexpected fact of nature! It would be compelling to explore more directly, even with a lander vehicle, for its own sake but more importantly because it would signal that there are fundamental things we don't yet understand, and that probably apply all over the universe. If Pluto were made of green cheese, that would then also engage the biologists, to try to explain it, because it would, so to speak, be a true udderly new discovery, and we'd need to know what type of cheese, and we'd want to find the source animals--and their grazing lands!

In that sense, if researchers must claw and scratch to find something to claim is seriously new in what is really rather ordinary, it's a problem. In terms of basic physical processes, these photos certainly provide new factual knowledge, and the voyage is certainly an engineering feat, but it's only very minor science. But it's early days yet; we will have to see if this mission really shows us anything other than local particulars about the nature of a couple of ordinary rocks roving around in space.

If not, then maybe we already know enough about the basic nature of these aspects of cosmology, and maybe we should be concentrating on other things, such perhaps as dramatically better kinds of telescopes (or other sensing instruments) to explore some of the more fundamental questions about the cosmos, of which there are plenty.

On a positive note, unless there really is something truly new about Pluto or its moons and so on, then what New Horizons shows is that our physical sciences and our instrumentation have been very good for quite some time. We've truly overturned the classics' idea of the earth at the center, surrounded in crystal spheres. We know what's 'out there', at least within the nearby visible universe, and its utter predictability in our solar system, along with the rest of telemetry data, show that we can extend this to the rest of the universe. We can invoke Newton's clear idea about what a 'law of nature' is, as he expressed in his Principia Mathematica: if you find something in some examined corner of existence, you know (if you've discovered the 'laws' correctly, and the cosmos is law-like) that everywhere else is the same, too.

That's why, for example, the orbits of objects, including Pluto and its moon, and the rest of the material in the Kuiper belt, and the various comets and other debris, and the stars, and gravitationally affected spacecraft, all behave as they do, essentially following the laws of motion and gravity. It is marvelous to know these things (our own area, biology is far from that level of understanding at present, but is making progress rapidly). But it is no longer transformative. Diminishing returns have clearly set in. That is the very nature of scientific progress. We should celebrate that this means we really do understand things about the universe. And we should move on to things we really don't yet know.

This sort of mission doesn't seem to tell us anything about dark matter and things of that sort, that may be part of the story even in our own solar system or galaxy, but hide under the space-probe-vehicles' radar. Why don't dark matter or dark energy affect spacecraft? Why doesn't inflation affect the trajectory of a spacecraft? These are questions that to a cosmologist may be quite naive, but they show the nature of new kinds of things we can now be asking about, rather than what particular humps and bumps a given space-rock has on it.

Too hard to please?
The images we're seeing are in many ways spell-binding. Just to imagine a bit of ice, not to mention a Rocky Mountain range of it, so far away and yet being seen close up, is quite amazing. It's not that that bothers us. Our objection to the venture itself is largely due to the cost relative to other human priorities.

This is less profound new knowledge than it is amazing technology giving us views no humans have had before. There's no taking away from that. But documenting another space object up close is not much different than doing another GWAS study of the genetics of some trait. OK, yes, OK--but we already know the general picture. It's time to delve into the deeper questions.


Michael Finfer, MD said...

There are indeed structures that look,like impact craters in that global view, but in that high resolution, close up view, there are none apparent, yet. You are looking at a lossy compressed version of the lossy compressed version that was received on the ground this week. The uncompressed version will not be down for a while. It will take 16 months to downlink all the data because the vast distance involved limits data transmission rates to 2 kb per second vs. several mb per second in today's typical internet connections. There may yet be impact craters in that image that may be too small to see in the current version.

With that said, the geologists estimate the age of a planetary surface by counting impact craters. What was said that the upper limit of the age of the surface in that image is 100 million years. It may or may not be younger still, depending upon what can be seen in the full version of the image that is yet to be received. This is a big surprise. The theorists are now going to have to find a way to keep a small, icy body warm for at least 4 billion years without any tidal heating.

The age estimate is for the area in that image. Other areas may be older or younger. It would be surprising indeed to find no impact craters anywhere in any of the images, and indeed they are there in other areas.

Ken Weiss said...

To the extent that what you say turns out to be accurate, then there may be a problem for the theorists. Whether it is as profound as you seem to suggest you think it is, time will tell. Will it be something really new, or a challenge to model known geologic forces and factors?

As is obvious, I have a mix of admiration and skepticism, because in my view these days it is almost impossible to separate the lobbying from the substance. I've seen too, too much of this in my own field. If I'm too skeptical, then there will be some really interesting scientific gains from this.

Of course, this doesn't change my personal view about funding priorities, especially that I think a much more serious debate should take place, absent the vested interests, about what human problems should take precedence. Again, of course, this is all about personal views, but that is what politics is.

Ken Weiss said...

The excitement and media publicity has many people entranced, because the pictures and achievements are very noteworthy. The issue we raise is not that, but is what level of really new science this addresses. Is it akin to finding a new fossil that actually changes our understanding of phylogeny in a major way, calling for new understanding of adaptations? Or is it like another GWAS hit that, yes, identifies another gene that contributes to diabetes but in not much more than a cataloguing way? Or sequencing another human that shows we are all different?

That Plutonics will involve some ad hoc explanatory efforts is not to be doubted, but the legitimate question is not just that, but whether it raises anything fundamental enough to have justified the mission or the flood of stories. The latter are being raised with great excitement, that may--may--be justified. But every thing any research does gets the same kind of treatment, and we raise questions about priority and relative importance (and that involves cost as well). Those who think it's all great science will have plenty of time to enjoy and think about it. Others may think there are deeper or more general questions that should take center stage.

David Evans said...

You are basing this on the first few days' comments on three high-resolution pictures (and not even the best versions of those, but the compressed versions which were sent first). Don't you think you could hold off on the snark until more of the data is in, and the scientists have had time to absorb it?

And don't go to the media, go to NASA. It's a cast-iron rule that if the media can possibly get science wrong, they will. Do the regular media distortions of gene therapy and evolutionary theory invalidate those disciplines?

Ken Weiss said...

Time will tell. NASA has been having pep rallies that match anything the 'news' media have been doing. Obviously, if some serious science that is more than ad hoc efforts to explain the Putonic particulars arise, then that will be good. The snark is intended, whether successful or not, in part to make what we write interesting to read, but yes, it is snarky. But any defender of this sort of project can be suspected of the same sort of bias, if opposite in direction. NASA scientists and spokesperson have been quoted by the media, so they aren't babes being misrepresented. So we'll all see what eventuates.

And the answer to the genetic/evolution question is that we think we are clearly similar in our treatment, and the successes are not invalidated but it is not, by any means, just the news media that are hyping things--they get this, as in the case of NASA and the ESA, as much from the agencies and investigators. The news media are not very knowledgable as a rule, so they have to do it that way, I guess. It's a mutual reinforcement operation.

But you may be right, and we'll just have see. We watch the same pictures with the same human interest in them as everyone else.

Michael Finfer, MD said...

Another lossy compressed image was released today that is truly amazing. It shows a terrain type that was totally unexpected on Pluto, and Charon seems to harbor similar surprises.

If you go to Nasa's Planetary Photojournal and compare these images to those of bodies of similar size, like Rhea, one of Saturn's moons, which is saturated with impact craters, you will appreciate why mouths are hanging open about these images. Terrain like that on Rhea is what I think most of the scientists expected of Pluto and Charon.

Anonymous said...

I worked at a NASA research center for several years (2001-2007). I wholeheartedly endorse the organization to be shut down. The 'mission' of NASA is entertainment along with various boondoggles to support worthless defense contractors.

Ken Weiss said...

It's the nature of our culture, media and entertainment drive. This doesn't take away from the wonder of stargazing and imagining what it must be like to be on Pluto, or that Pluto has real existence, all happening without anybody being aware of it, until now.

Real problems exist right here in our own neighborhoods on good ol' terra firma, so the public must be distracted with bread and circuses. If people like Trump have $10 billion, they and many in the actual entertainment industry could easily pay for these distractions. If this is a way to keep defense contractors funded without calling it 'defense', then that should be stopped so society can decide what legitimate defense research interests we have and make that a clear and legitimate part of DOD's budget.

Still, there are many interesting questions in physics and cosmology that are far more central and profound than explaining some ice mountains and hideaway craters. Dark energy and matter, entanglement, gravity waves and the nature of gravity, multiverses or cosmic inflation, and so on--and these are just the fundamental issues I happen to have heard of.

David Evans said...

I can't help imagining our first meeting with an alien species:

Did you explore your own solar system thoroughly?

No, we thought it more important to work on the Big Questions: dark matter, multiverses, the meaning of life...

Did you solve any of the Big Questions?


Ken Weiss said...

Well, your tale is science fiction and we've been saying the fiction industry ought to be funding this. In real life, any alien that could get here would have figured out warps or worm holes to do it, and would wonder why we spent our resources taking snaps of dead rocks rather than doing some actual science, so we would detect aliens early enough to varporize them, because after saying this the ETs would vaporize us (not because we were a threat, but because we were so stupid as not to be worth their intersteller conservation efforts).

Anyway we certainly disagree about this, so let's give it a rest.