Follow-Up on Saturn’s Moon Titan, its Craters, and its “Youth”

As a quick follow-up to my last blog post, a reader wrote in and their comment was published on the Creation.com website. From Mark V. of New Zealand:

You mentioned that Titan has fewer impact craters than would be expected. Does this mean that a moon or a planet which has a lot of impact craters such as earth’s moon Mercury Mars etc. is therefore old? I would suggest that the reason for the few craters is Saturn, which with its much higher gravity, would draw the various comets meteors etc away from Titan.

The CMI (Creation.com / Creation Ministries International) astronomy guy, Jonathan Sarfati, responded (links removed):

In answer to your question, no it does not. This would be committing the fallacy of denying the antecedent, as explained in Logic and Creation. The explanation for lots of craters on the moon is a brief intense swarm of meteoroids, travelling on parallel paths, probably during the Flood year. This is supported by ghost craters, evidence of rapid succession of impacts, and by the fact that 11 of the 12 maria are in one quadrant, evidence that the major impacts occurred before the moon had even moved far enough in one orbit (month) to show a different face to the swarm. See On the origin of lunar maria and A biblically-based cratering theory.

In my original blog post, I said there were two alternative ideas to cratering that would save the creationist idea behind this article:

The alternative is that the crater calibration stuff is off, and radiometric dating is wrong. So, the Moon is not 4 billion years old, it’s 6000 years old. With the crater population of Titan, that means Titan can only be, oh, around 15-150 years old. Except that it was discovered in 1655.

Or, the entire crater calibration stuff is completely wrong. Which means you can’t use it to say Titan’s surface is young, which is what he is claiming — that it is young because scientists are showing it’s young because it has few craters.

When writing that, I specifically left out the special pleading idea even though I thought that CMI would probably try to use that in responding to anyone’s question. Which they did. The special pleading is that, “Hey, we actually can’t use the Moon as a guide to cratering because its craters came in a quick, special burst!” (that some creationists attribute to Noah’s Flood because, well, ¿why not?)

I left that out because it’s really a form of my second alternative: The crater calibration techniques are bogus, you can’t use them. By Jonathan Sarfati claiming that the lunar cratering is unique and special, it means that the cratering calibration is way off because cratering chronology is BASED on the Moon. And, if it’s off, if we don’t know how to calibrate any ages with craters, then you can’t possibly use them to say Titan’s surface is young or old, which is the basis of the claim that the CMI article is based on.

So again, this doesn’t solve the problem, it introduces more problems and shows yet again that the young-Earth creation model is internally inconsistent.

You can be a young-Earth creationist and claim Titan is young (you’ll be wrong, but you can claim it). Just don’t use the crater chronology to do it. If you do, you’ll wind up going in circles as I’ve demonstrated in this and the previous post. Why? Because it’s inherently inconsistent to do so. If the consequence of a CONSISTENT crater chronology were that Titan’s surface was <6000 years old, then that would be the mainstream science thinking on the subject. It's not. Because the crater chronology doesn't show it, if you use a consistent chronology across solar system bodies.

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Under a Creationist’s Reasoning, Titan (moon of Saturn) Is Just a Few Years Old

Introduction

I’m always amazed at the penchant for young-Earth creationists (YECs) to use science for part of their argument and creationism for another part, when it relies on the science being right, but they’re arguing that the science is wrong.

If that was confusing to you, let me explain …

Crater-Age Modeling

The basic idea behind using craters to estimate the age of a surface is that, if you have an older surface, it’s been around longer and has had more time to accumulate more craters. So, more craters = older.

We can use samples from the Moon to correlate crater densities with absolute ages and get a model for how many craters of a certain size equals a certain age.

That’s the basics … if you want more, see my podcast, episodes 40 and 41: Crater Age Dating Explained, Part 1 and Crater Age Dating and Young-Earth Creationism, Part 2.

So, we have, from the moon, the idea that a heavily cratered surface equates to one that’s been around for billions of years. This REQUIRES radiometric dating to be correct and the basics of crater age-modeling to be correct.

The implication is that a surface that has just a few craters is much younger.

Titan

Titan is Saturn’s largest moon, its atmosphere is thicker than Earth’s, and the Cassini and Huygens probes have shown that its surface is geologically active. It also has very few impact craters.

YEC

Enter David Coppedge, a man I’ve talked about on this blog quite a bit. His latest writing was published by Creation Ministries International, “Saving the ‘Billions of Years’ Age of Titan.”

In his article, he is keying in on a recent popular article that explains that Titan’s surface looks young, and there are a few ways that it can still be geologically active (as in have a young surface, like Earth) and still have formed over 4 billion years ago.

The problem is that, for us to say it looks young, that’s because of the few impact craters. Versus old, that’s because of radiometric dating and then the calibration to lots of impact craters on the Moon. For Coppedge to say (effectively) “Yes, scientists are right, Titan’s surface looks young because it has few impact craters,” then he is REQUIRED to accept the basics of the crater chronology system, which he clearly doesn’t. Because, if Titan is young because it has few craters as he is agreeing with, then the Moon and other bodies must be much older under that same crater chronology system.

Yes, confusing. To get to point B, he must accept A. He thinks B is true, but he does not think A is true. Hence the confusing cognitive dissonance he just ignores.

Alternative

The alternative is that the crater calibration stuff is off, and radiometric dating is wrong. So, the Moon is not 4 billion years old, it’s 6000 years old. With the crater population of Titan, that means Titan can only be, oh, around 15-150 years old. Except that it was discovered in 1655.

Or, the entire crater calibration stuff is completely wrong. Which means you can’t use it to say Titan’s surface is young, which is what he is claiming — that it is young because scientists are showing it’s young because it has few craters.

Final Thoughts

Does anyone have a headache now? I think I gave myself one.

Podcast Episode 90: Investigation into Billy Meier’s Alleged Foreknowledge About Stuff About Jupiter and Saturn

Investigating
When people knew what about
Jup’ter and Saturn.

I’ve been doing some research on and off for this episode for quite awhile and finally had enough to post it: Episode 90: “Investigation into Billy Meier’s Alleged Foreknowledge About Stuff About Jupiter and Saturn.” The shownotes for this episode are extensive with lots of references. It’s been scheduled as Episode 90 for about two months. I decided to do it because I found it an interesting scavenger hunt, despite the fact that UFO-related posts are among my least-read blog posts.

The blog entry I reference towards the end of the episode is from January: “How Astronomers Are, According to Popular Press, Constantly Discovering the Same Thing.” I recommend looking through it because it’s a good example that has nothing to do with the Meier case where even peer-reviewed, professional science papers will sometimes ignore work that has shown the same “new” thing before, and it’s a good example of how press releases can play up various “discoveries” … even if they’ve been made before.

The podcast episode also has a few notes at the end, and there’s some feedback clarifying the discussion about why oxygen isotopes are important for understanding where objects formed in the solar system.

 

Given what’s happened in the past when I’ve talked about Meier’s material, I’m going to reiterate my comments policy: Comments need to be on-topic, and I make the final decision of what comes through; I do not owe you an explanation if your comment is not posted, my comments policy is pretty clear. Any comment to this post needs to be specifically about this podcast episode.

If you’re going to dispute material in it, you need to provide specific references and be specific about what you are disputing. You need to be succinct. That means no lengthy essays. That means no posts with numerous links to random stuff. That means no links to videos about trees — no embedded videos period, I will remove them and I will remove posts that are simply a bunch of random links to Meier material, especially if they do not support the specific thing you are refuting / referencing. That means not debating whether trees in a video are real or models.

This episode is specifically about certain claims about Jupiter and Saturn, whether those claims/statements were true, and whether it was known or openly speculated before Meier’s writing that they were true or existed, which is what the claim is for Meier’s prophecy: “… with literally dozens of other such documented examples of Meier’s having published specific, accurate information years, and even decades, before terrestrial scientists, the case must be recognized as being authentic based on these irrefutable facts alone.” It is not the claim that this stuff was known on Earth but Meier didn’t have access to that information so he still got it from ETs — and if that’s what is going to be claimed now, then that is an unfalsifiable and unverifiable claim and is moving the goalpost.

Podcast #72: Solar System Mysteries “Solved” by PseudoScience, Part 1 – Iapetus

Exploding planets,
Alien spaceships … Why is
Iapetus weird?

The subject of this episode is Saturn’s moon, Iapetus, and two mysteries about it that various branches of pseudoscience have claimed to solve: the brightness dichotomy via an exploded planet, and the equatorial ridge via a spaceship.

This is the first of what I plan to be a series much like “The Fake Story of Planet X” series — different mysteries of the solar system that have a pseudoscientific explanation and may or may not have a real science (agreed upon) explanation. Let me know what you think of the concept. Future ideas for shows are the Pioneer Anomaly and Mars’ crustal dichotomy.

Otherwise, there’s a bit of feedback and then I get into the puzzler from last time and one announcement.

Well, I sorta snuck in a second announcement — I’m headed to Australia, December 18 – January 20. I’ll be centered in Melbourne (which I enjoy pronouncing as “Mel-born-EE”) for most of the trip though should make it up to Sydney (I wanna see the Great Barrier Reef!). So, dinner in each city if I can round up enough interest. I’m slowly learning that Australia is not just a 5-hr drive across, so I’m less likely to make it to the eastern half. We’ll see if I can increase my Australian listenership in the meantime to make a dinner here or there worth organizing.

What Happens When All the Planets Line Up Against Us?

Introduction

This is a claim that has persisted for a long time, and though people who believe in the 2012 stuff have propagated it, it is not specifically a Planet X / 2012 claim: If all the planets (plus our moon) lined up opposite the sun, they would pull us out of orbit. As the “lolcatz” say, “Oh noez!”

Gravity

The force felt by an object due to gravity is a very simple mathematical function, codified by Newton’s Universal Law of Gravity:

In this equation, F is the force felt, G is the Gravitational Constant, M m are masses of the two objects in question, and r is the distance that separates them.

To figure out how much more or less two different objects will pull on the same object, we can simply remove one of the two masses, so the equation simplifies to F = G * m / r².

The Math

To determine the relative forces, one simply needs to know the mass of the planets and sun, and the distances between Earth and those objects. This can be found in any basic astronomy textbook or online source. One then can simply plug in the numbers and figure out the forces.

For the sake of argument, let’s say the sun is on one side of this tug-of-war, and the moon, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, and even Pluto are all on the other (Venus and the sun don’t count ’cause they would have to be on the sun’s side). Let’s calculate the force first due to the sun:

Object	Mass (1024 kg)	Distance from Sun (106 km)	Distance from Earth (106 km)	Relative Force
Sun	1,989,100	—	149.6	0.0059

Alright, now let’s do all the rest, remembering that for the planets, we’ll need to subtract out the distance between Earth and the sun from what are commonly quoted as the planets’ distances:

Object	Mass (1024 kg)	Distance from Sun (106 km)	Distance from Earth (106 km)	Relative Force
Moon	0.07349	—	0.3844	3.32·10-5
Mars	0.6419	227.9	78.32	6.98·10-9
Jupiter	1,899	778.6	629.0	3.20·10-7
Saturn	568.5	1434	1284	2.30·10-8
Uranus	86.83	2872	2723	7.82·10-10
Neptune	102.4	4495	4345	3.62·10-10
Pluto	0.00125	5906	5756	2.52·10-14
Ceres	0.00095	415	265.4	9.00·10-13

Final Thoughts

This is a really short post because it doesn’t need to be long. To be perfectly honest, I was actually surprised at how small the force of Jupiter actually is on Earth relative to the sun. If we add up the force from all of the other objects, we only get a force that is 0.566% as strong as the sun’s. And then if we take the moon out of the equation because that would be the first to move out of the alignment, then we have a force of only 0.000592% as strong as the sun’s.

If we look at Venus if it were also lined up, helping the sun, its force is 1.90·10^-7, or about half as much as all the other planets (again, leaving out the moon), so it would cancel 54% of the effect of all those other objects (again leaving out the moon). The force from Mercury is only about 1/3 that of Mars.

So really, if anyone who makes this claim were to bother to spend about 10 minutes looking up the numbers and plugging them into an Excel equation (what I did), they would quickly see that this claim is simply and utterly nonsense. And this is besides the fact that the planets aren’t lining up any time soon on the other side of Earth to try to pull us out of orbit.

The “Youthful” Dynamics of Saturn’s Rings – A Preemptive Anti-Young-Earth Creationism Post

Introduction

Several months ago, I posted on a young-Earth Creationism (YEC) article about uranium-238 radiometric dating of the solar system. In that article, I stated that I had one of my numerous psychic premonitions when I read the original science article that the creationists would use it somehow. But, I had no documentation backing that premonition up so I can’t apply for the James Randi Educational Foundation’s $1 Million prize. Darn.

In a much earlier post, nearly a year ago, I wrote a post on more YEC claims that the Saturnian system is young. I mentioned that they were indirectly using my own research in their claims.

Now, a year later, the science journal Icarus has its April special “Cassini at Saturn” edition out, and I happen to have a first-author paper in it. In addition, on Friday, the March 19, 2010 issue of the very prestigious journal Science has a 5-page article that kinda summarizes several of the papers in Icarus – including citing mine – that show that Saturn’s rings aren’t just boring slabs of particles orbiting away.

Call me “psychic,” but I have a feeling that some YECs will be using this in another of their attempts to propagate their version of a literal biblical worldview. This post is an attempt to summarize my own research on the rings and to show why the dynamics that we see are fully consistent with an old ring system.

Warning: This blog post rambles a bit more than usual. In it, I outline how models are created in astronomy, how that applies to the mass of Saturn’s rings, how the mass is linked to the age of the rings, and then my own research into the mass and hence age. It’s really a background post so that if/when the YECs pick up on this story I can just refer to it for background and just address the claims on that post.

How a Scientist Starts a Model

The entire purpose of physics is to mathematically produce a model that replicates the observable world. When a scientist starts out to create a model of a complicated system – say, Saturn’s rings – they will start with the simplest model possible and then add layers onto it in complexity.

Very early on, the rings were thought to be solid – thin disks that orbited Saturn. Later, that view changed to one where individual particles were thought to make up the rings. That’s the view we hold today.

In terms of the dynamics involved, in modeling the rings, one starts with a bunch of particles in orbit around a large central mass (the planet), and uses basic physics to describe how they would interact with each other. By adjusting parameters such as how big the particles are, how many there are, etc., you will get different results, and you can use the observable data to then constrain your model.

Some basic parameters that are still somewhat unknown about Saturn’s rings are the makeup of individual particles, their density, how “sticky” they are, how large they are, and how much material is actually there.

Old Voyager Results

Around the time I was born, the starship Voyager spacecraft (1 and 2) passed by Saturn. One of the many observations they made is called a “stellar occultation” through the rings. An “occultation” is when you block out a background object with a foreground one. In this case, a “stellar occultation” is when a star is blocked out, and this was by Saturn’s rings. The purpose was to measure how much light got through the rings in order to measure their “optical depth.” “Optical depth” is, well, how much light can get through something. An optical depth of 0 means that everything gets through.

Anyway, based on the Voyager measurements, which showed significant optical structure in the light that got through the rings, we had to complicate our models. And by “we” and “our” I mean the ring-studying community … I hadn’t quite entered kindergarden. The rings were still modeled as particles, but they were modeled like “granola bars” (in what is referred to as a “granola bar model”): Slabs of optically thick (no light gets through) clumps/aggregates of ring particles separated by optically thin (light gets through) gaps. In developing their models, the question now focussed on the width of those slabs and the width of the gaps between them.

It was from these models that values are still quoted today in terms of the height of the rings (“several yards” – though some places say “less than a mile”), the mass of the ring system (around the mass of the moon Mimas), and perhaps most importantly for this discussion, the age of the ring system.

The Copernican Principle

There’s a principle in astronomy that states, “We do not live in a unique time nor place until shown otherwise.” I’m not going to argue here whether that’s a good principle to live by and do research by, what its roots are, nor its “validity.” Regardless, it’s there and I personally think it’s fairly good to stick with for the time being because it forces us to do more work.

What came out of the Voyager results is that the ring system seemed “young.” “Young” here is in quotes because it means something on the order of 100 million years. That’s only 2.5% the age of the solar system, hence “young.” Part of the reason for this is that the “dynamical lifetime” of the rings of that mass is much less than the age of the solar system — the ring particles are slowly raining down on Saturn and in the future the ring system will be gone. But, that unsettles astronomers because of this principle that we don’t live in a unique time nor place.

It also makes different formation mechanisms much more difficult to justify statistically. In other words, it is much easier to justify, for example, two moons crashing together – or a moon and a large asteroid or comet crashing together – during the solar system’s formation or very soon afterwards when we know those kinds of collisions were common than it is to justify that happening recently, when the solar system is fairly well behaved.

My Work

I’m not going to discuss in detail my modeling of the ring system. If people are interested, they can e-mail me or post in the Comments asking for a copy of the 15-page paper. But I will give you the basic idea:

Cassini is a craft that’s been in orbit around Saturn since 2004. Besides many truly awe-inspiring pictures it’s taken, an instrument on it also performs stellar occultation measurements through Saturn’s rings. Over the course of nearly 6 years and well over 100 such observations, we have a much more detailed understanding of the optical thickness of the rings — how difficult it is for light to get through any given location in the rings as a distance from Saturn.

For my research, I performed what are called N-body simulations, where in the computer I created a mini saturnian ring section. I varied many different properties – including the ones I mentioned a few paragraphs ago – and I let the system evolve from an initially random state. I then simulated a Cassini observation through my little ring section.

I then compared the results of my simulated occultation to the real ones. From these results, I was able to further narrow-down some of the basic, fundamental properties of the rings. The most important one was that I was able to place a new, minimum mass constraint on the total mass of the ring system. This new constraint is about twice as large as the original one – about 2 times the mass of Saturn’s moon Mimas.

How Does Mass Relate to Age?

Directly, it doesn’t. But indirectly, it does, and I’ll explain here two examples of why.

One is the example that I explained above — if you have more material, then the dynamical lifetime is longer, and you can make the rings correspondingly older by the simple fact that they are still there today to be observed.

A second reason why is that of pollution. As the ring particles orbit Saturn, micrometeorite impactors rain down on the rings and will pollute them. Through various observations and modeling constraints (including mine), we know that the rings are more than 90% water-ice. This is really pure ice and raises the question of how something so old could be so fresh, especially with the pollution from other material.

The answer lies at least partially with the mass: If you have more material there to begin with, then you can more easily “hide” the pollution. For example, if a factory spits out sewage into a small lake, then after a day that lake will look pretty gross. But if that factory spits out the sewage into the ocean, it can do it for many, many years before the ocean is going to show any signs of being polluted. The same is true with the rings.

Hence, as a result of my paper and placing a new minimum mass constraint that’s larger than before, you can push the age of the rings further back in time. And my work is just a minimum estimate — if I had faster computers and more time and weren’t actually doing research on something completely different, then I could push the simulations to many more particles over a larger area and simulate even more massive rings to really try to nail down that mass. But, in 2017 or whenever they choose to kill off Cassini, it will fly between the planet and the rings and we will be able to directly measure the gravitational tug on the craft by the rings and should be able to answer that question. But I digress …

Anticipated YEC Responses

I don’t actually expect YECs to directly respond to my paper in particular. I think it approaches the problem too indirectly for them to take notice and think it’s worth writing about.

What I do expect is for them to respond to the Science article. It’s title is quote low-hanging fruit for the YECs: “An Evolving View of Saturn’s Dynamic Rings.” Wow. They have both “evolving” and “dynamic” in there. I expect that:

(1) Creationists will somehow try to link this to “darwinism” and that an old ring system “belief” is driven by some desire to provide “millions of years” for evolution to occur.

(2) Creationists will have issues with the Copernican Principle and argue that we do live in a specially created time and place where “the heavens declare the glory of God.”

(3) I expect the creationists will key in on the dynamical nature of the rings that we see today. This is not something that I talked about in this post much at all. Very briefly, it has to do with moving from the “granola bar model” to self-gravity wakes of material clumps that we have observed in simulations, theory, and observations that move around, exchange material, and produce bumps, ridges, spokes, and cusps in the rings that Cassini observes. If they do happen to address this, then I’ll discuss it more in my response post.

Final Thoughts

There you have it. I have a prediction out there. I’ve preemptively discussed my own research in this area and hopefully explained it in a reasonably clear way. Now let’s see if the YECs bite.

Is Saturn a Young System? Apparently, According to the Institute for Creation Research

Introduction

In the last few days, I’ve seen a few blog posts about Saturn being a young system on the usual creationist sites or those responding to the creationist sites, and being a bit behind in my blog, I thought I’d check out the usual suspects. Predictably, I found the article posted yesterday, May 7, 2009, on the Institute for Creation Research by my own favorite, Brian Thomas (who I picked apart in this blog post.

The article in question now is entitled, “Planetary Quandaries Solved: Saturn Is Young.” Okay, I admit I needed to take a deep breath with this one before reading it. After all, you’d think that if scientists had really discovered that Saturn had been created/formed recently, it would be all over the news, right? So right off the bat, the title is misleading, but understandable for a creationist website.

Then I picked through some of the references. Why? Because I actually do research on Saturn’s rings. I will be submitting revisions to a 50-page manuscript to the journal Icarus in the next 3 days that should be published in a special edition of the journal at some point this summer, and the conclusions from my simulations are that the ring system is at least 2 times as massive as before, likely more, and the implications are that the system can then easily be a corresponding amount older (e.g., at least 2 times older).

And, lo!, one of the references in the article directly cites my work — a ScienceNews article from September 2008. (Check out paragraph 4 of the article.) So now, it’s personal — Brian Thomas is using MY research (in part) to advance his creationist agenda, and I will not be silent about it. Hence this blog post. 🙂

What Is the Evidence the Saturnian System Is Old?

Let’s ignore all of the outside evidence that it’s old. Let’s ignore solar system formation models. Let’s ignore standard conventional wisdom. Let’s ignore the scientific problems about biblical creation. What is the evidence that the system is old, or at least not young.

Well, being a crater counter when I’m not running simulations of Saturn’s rings, I point to craters. Craters are used throughout the solar system as the only cross-planetary method of relative dating methods. In other words, how many craters a solid object has is the only thing that we can measure, at present, that gives us the relative ages of two solid surfaces.

Crater ages have been calibrated via Apollo lunar sample returns, and so – at least for our moon – we know that a certain number of craters per unit area corresponds with one age, and a different number corresponds with a different age — and we know what those ages are to reasonable accuracy for the moon.

Much work has been done and is being done to try to extrapolate what we know from our moon to other solid bodies, including Mercury, Venus, Mars, and the giant planets’ satellites. While the work isn’t perfect and uncertainties remain, the state of the research is that we can tell the difference between an object that is 6000 years old or 4 billion years old.

The surface of Titan? The last number I saw is that there are around 150 impact structures that have been observed, so the present-day surface age of Titan is reasonably young. Yes, I admit that — I’m not hiding it.

What about the surface of the other moons, such as, say, Iapetus? Well, take a look at the image to the right. There are A LOT of craters there, and the surface age of Iapetus is likely on the order of a few billion years (I say “likely” because I haven’t actually done the crater counts there). Now, unless you’re going to engage in some very special pleading, this is pretty good independent evidence that at least some parts of the Saturnian system is old.

Enter the Argument for Youth: Saturn’s Rings

I grew up reading that Saturn’s rings were young – probably formed only 100 million years ago after the breakup of a medium-sized moon, about the size of Saturn’s moon Mimas (shown on the right). That was based on a few things, including estimates of its mass from Voyager data as well as spectroscopic observations showing that the rings are fairly “fresh,” showing relatively little contamination by, basically, space dust.

This was still the predominant idea in 2002, when Jeff Cuzzi made his quite that Brian Thomas uses in the second paragraph of this article:

A history of mystery surrounds the youthful features of Saturn’s rings. Jeff Cuzzi, a planetary scientist at the NASA Ames Research Center, said in 2002, “After all this time we’re still not sure about the origin of Saturn’s rings….There’s a growing awareness that Saturn’s rings can’t be so old.” Cuzzi said, “There are two reasons to believe the rings are young: First, they are bright and shiny like something new. It’s no joke.” Indeed, after millions of years, the icy rings should have collected so much space dust that they should be charcoal-colored by now. Second, after only a few million years, the little moons embedded among the rings should have “flung away. This is a young dynamical system.”

And, this was still an issue in 2006, when I was just starting my simulations. The third paragraph of this article cites Josh Colwell in a presentation he gave. He was listing some of the current problems in a few-billion-year-old rings system, but the problems were still based on old data estimates for both the mass of the ring system and the viscosity of the particles (viscosity can be thought of as how well particles can transfer energy from one to another or how well they flow — water is not very viscous but molasses is).

Enter the simulations. I use Mark Lewis’ code for these simulations, and I make a point of that because Mark is quoted in the fourth paragraph of the ICR article:

Mark Lewis of Trinity University in San Antonio cautioned that it is still not known how they really clump. “It isn’t as straightforward as saying that high-density particles would lead to more clumping.”

This is true. There are many different parameters that go into these simulations to model the physics involved. Even though I explored a huge range of parameter space in my simulations, performing over 150 different N-body simulations that took over 27,000 CPU hours to run, I still did not explore the whole range of space, and a few of those parameters do affect how ring particles clump together.

Clumping is important because it directly affects how we estimate the mass of the rings. If the rings do not clump at all, then for every particle it will block an equal amount of light. Kinda like if you spread a lot of sand on a sheet of paper and you spread that sand evenly around, you will only see a little of the paper through the sand. But, if you use the same amount of sand and start to make little sand piles, you will see more and more of the paper.

That’s how we estimate the mass of the rings – by how much paper (how much light) can be seen through the rings. And, if the ring particles are clumped together, then you need many more ring particles to get the same amount of light blocked. What my simulations show is that clumping plays a much larger role than previously thought, and so we need more material in the rings to match the observed light-blockage.

Why do more massive rings mean that the ring system is older – or can be older? Because more massive rings means the viscosity is higher and so they spread out more slowly (one of the arguments they were young is that they would spread out too quickly). Also, it means they can be older because the same amount of pollution will get spread out over a larger area, and hence they won’t be as “dirty.” So, arguments that they are young because they don’t show a large amount of pollution can be answered that the pollution is just better hidden than we thought because there is more material within the rings to get polluted.

What was the connection to me here? Well, they’re my simulations. And that fourth paragraph has a quote from an article that talked about my results. Hence why I take this a little personally.

Moving On to Enceladus

In paragraph 5 of his article, Brian Thomas says that Saturn’s moon Enceladus “shows no hint of being 4.5 billion years old, but instead appears remarkably young.” I’m not going to harp on Brian’s grammar mistake here because I’m sure I have made my fair share of mistakes in this article grammar-wise, but I will say that it’s a poor journalist who doesn’t know what a sentence fragment is.

Anyway … this statement is simply wrong. It is true that the geysers that were discovered coming from Enceladus’ south polar region were a surprise, and they have made many people in the planetary community excited to find out why they are there. (Note – yes, new discoveries that challenge old models make scientists happy, not upset, as creationists would have you believe.) And a lot of Enceladus’ surface does appear to be young. However, a fair portion of the surface also appears to be very old, as shown in the picture on the right. Yes — I’m talking about all those craters.

Final Thoughts

That’s really the point of this article. So, no, the planetary quandary has not been “solved” to say that Saturn is young. Rather, the ring system can still easily be old based on the latest (and if I do say so myself, the greatest) simulations, and even though some features of Enceladus appear young and active, there are other parts of the moon that tell the tale of being ancient.