Exposing PseudoAstronomy

April 23, 2015

How Do We Know How Old Stuff Is on the Moon?


Introduction

While this movie is branded under “Exposing PseudoAstronomy” for legal reasons, it has less to do with popular misconceptions/conspiracies/hoaxes and more to do with real science. This is my third more modern, lots of CGI movie, and my second to explain a research paper that I wrote.

In the movie, I go through how the lunar crater chronology is the fundamental basis for how we estimate the ages of surface events across the solar system. I also explain how my work affects the lunar crater chronology and what can be done to better constrain it.

I’m still waiting for a young-Earth creationist to claim that because of a factor of 2 uncertainty, 4.5 billion becomes 6.019 thousand.

I also wrote a blog post about this for The Planetary Society. Because it was posted there over two weeks ago, I think it’s fair game to repost here. You can click on any of the images for larger versions, and all of them are screenshots from the YouTube movie.

Planetary Society Blog Post

Three years ago, I started a project to replicate work done by various groups in the 1970s and 1980s. When the project was completed, the result implied that much of what we think we know about when events happened in the solar system were wrong, needing to be shifted by up to 1 billion years. I presented this in a talk at the recent Lunar and Planetary Science Conference at 8:30 AM, when most people were learning about the latest results from Ceres.

The project started simply enough: I downloaded some of the amazing images taken by NASA’s Lunar Reconnaissance Orbiter’s Wide-Angle Camera (WAC) that showed the Apollo and Luna landing sites. Then, I identified and measured the craters (my dissertation work included creating a massive global crater database of Mars, numbering about 640,000 craters).

The reason to do this is that craters are the only proxy we have for ages on solid surfaces in the solar system. We can determine the relative age of one surface to another (is it older or younger?) by looking at which has more craters: The surface with more craters will be older because, when you assume that craters will form randomly across the body, then the surface with more craters has had more time to accumulate them.

How to Use Craters to Understand Ages

Basic principle behind this work. (Background image © NASA/ASU; composite © S.J. Robbins.)

If we want to use craters for an absolute timeline – as in, actually put numbers on it – then we need some way to tie it to real ages. This was made possible only by the United States’ Apollo and the USSR’s Luna missions that returned rocks from the moon that could be radiometrically dated in labs on Earth.

With these radiometric ages, we then identify the craters on the surface those rocks were gathered and say that a surface with that many craters per unit area is that old.

That’s the lunar crater chronology: The spatial density of craters larger than a standard size versus radiometric age (we use 1 km as that standard size). This crater chronology is then scaled and used as a basis for the chronology across the rest of the solar system. When you hear someone say that something on the surface of Mars is X number of years old, chances are that’s based on the lunar samples from the 1960s and 70s and the crater counting done 40 years ago.

Apollo 15 Landing Site

Example landing site area, Apollo 15 (yellow star). Blue outlined areas indicate regions on which craters were identified, blue shaded areas were removed because they are a different type of impact crater, and blue circles are the craters mapped and measured. (Background image © NASA/ASU; data and composite © S.J. Robbins.)

And, that’s where my project came in. While the rock samples have continued to be analyzed over the decades, the craters were not. It’s easy to assume that the researchers back then did a great job, but by the same token, science is about replication and re-testing and we have developed new ways of doing things in the crater community since the Apollo era. A simple example is that the crater chronology requires a spatial density, and therefore you need to know the area of the surface on which you have identified craters. Over the past 40 years, we have better understood the shape of the moon and now have computers to allow for much more precise area calculations. This can result in changes by 10s of percent in some cases.

When I had finished my reanalysis, my results differed for many of the landing sites, in some cases by a factor of 2 from what the standard is in the field. I was surprised. I checked my work and couldn’t find any mistakes. So, I combed through the literature and looked to see what other people had published. I ended up finding a range of values, and only in one case was my result at the extreme low or high of all the published results. I showed my work to colleagues and none of them could find any issue with it. So, eventually I published it, early last year.

The Lunar Crater Chronologies

The new (blue) and old (red) chronologies and the data used to fit the model. The vertical axis shows the spatial density of impact craters larger than or equal to 1 km in diameter, and the horizontal axis shows the age of the surface from radiometric dating of collected rock samples. (© S.J. Robbins)

When I fit my crater data to the radiometric ages, my fit function showed a difference with the standard that has been used for three decades: Surfaces assigned a model age of about 3.5 to 3.7 billion years under the old chronology were older, by up to 200 million years. And, surfaces younger than about 3.4 billion years under the old chronology are younger, by up to about 1 billion years.

Differences Between the Lunar Crater Chronologies

The new and old chronologies in blue and red (top), and the difference between them in terms of model surface age. (© S.J. Robbins)

There are a lot of implications for this. One is that volcanism on the terrestrial planets may have extended to more recent times. This would imply that the planets’ cores stayed warmer longer. Another implication is that the large reservoirs of water thought to exist around 3 billion years ago may have existed for another 500 million years, with implications then for favorable environments for life.

But, something that I added near the end of my LPSC talk was the question, “Am I right?” The answer is an unsatisfying, “I don’t know.” I of course would not have published it if I thought I was wrong. But by the same token, this type of science is not about one person being right and another being wrong. It’s about developing a model to fit the data and for that model to be successively improved as it gets incrementally closer to explaining reality.

And, there are ways to improve the lunar chronology. One that I’m a big advocate of is more lunar exploration: We need more data, more samples gathered from known locations on the moon’s surface. We can then date those samples – either in situ or in labs on Earth – and along with crater measurements add more tie points to the lunar crater chronology function. Right now, there is a glaring gap in the sample collection, one that spans 2 to 3 billion years of lunar history. A single point in there could help differentiate between my model and the classic model. And more data would be even better.

Until we land robotic missions to send back samples from other planets or that can date samples there, the moon is still our key to ages across the solar system.

February 27, 2014

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.

February 24, 2014

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.

June 26, 2012

Podcast Episode 41: Craters and Creationism, Part 2


In a slightly delayed offering, episode 41 has been posted. Sorry to say that episodes over the next month may be delayed by a few days, as well, for I have several trips coming up and won’t have my equipment with me.

As the title suggests, this episodes details a few claims by creationists to try to argue that craters really show the solar system is only 6000 years old instead of the solar system being around 4.5 billion. It may get a bit technical at times — sorry.

June 16, 2012

Podcast Episode 40: Crater Age Dating Explained, Part 1


This is a bit of a longer episode. ‘Cause, this is what I do.

I give you a pretty detailed overview of how crater age dating works, the difference between absolute and relative age dating, how we can assign absolute ages to the relative ages of craters, how geologic mapping works and why it’s important for crater age dating, and then many of the known problems and caveats with the method.

Finally, there’s an open question about the puzzler: Is it worth doing? I wanted to do it initially to get interaction between me and the listeners. But participation has been around 1 for each. So if you have any opinion regarding the Puzzler, please let me know in the Comments to this post.

June 9, 2012

Podcast Episode 39: Young-Earth Creationist Attempted Refutations of Radiometric Dating


A slightly delayed episode is finally up. Part 2 of the series of 2 on radiometric dating, part 2 of the series of 4 (this month’s theme) on dating techniques. I talk about four of the main categories of claims that young-Earth creationist arguments fall into in their attempts to refute radiometric dating.

It’s also the first regularly formatted episode since #35, including the main segment, new news, Q&A, feedback, puzzler, and announcements.

June 1, 2012

Podcast Episode 38: Radiometric Dating Explained, Part 1


This is Part 1 of two parts, the next to be in the next episode, conveniently, and will discuss what young-Earth creationists say about the topic.

But in this one, I give you a 50-minute interview with geologist Rachael Acks who explains some of the history of radiometric dating, the very basic physics of it, how it works in practice, and some cases of when and why you can’t use the method.

This month begins a four-part series (though it’ll be labeled as two Parts 1 and 2) on age-dating techniques and then the young-Earth response. The first set is radiometric, second set will be craters. It’s a bit of a different thing, so we’ll see how it works out.

Note that because this interview ran longer than I like to make normal episodes, I’m pushing the not-main segments to Episode 39.

May 19, 2012

Podcast Episode 36 BONUS! – GAPs Young-Earth Creationists Must Believe or Ignore (Geology, Astronomy, Physics)


I ended up giving my talk anon how YECs arrive at their conclusion of a young Earth versus how “secular scientists” do it. This episode has been posted in both audio and video. Hopefully they both work, and hopefully not too many will yell at me for posting a 90 MB video without warning to the RSS feed. The video is MP4 format … that is the general universal format these days, right?

April 28, 2010

Young-Earth Creationists Need to Have a Consistent View Things: Radiometric Dating and Noah’s Ark


Introduction

One of the best and most reliable ways to determine the absolute ages of a material is through radiometric dating. Because of this, and because they show the age of things to be older than 6000 years, young-Earth creationists (YECs) have spent decades trying to show that it doesn’t work or just claiming that assumptions that scientists make are not true.

Their attempts at this include bringing samples of newly formed lava to a lab where they find an age of a few million years and then laugh saying that it only formed a decade ago. (Two issues there are that (1) the type of dating employed isn’t accurate for a sample younger than 500,000 years, and (2) they dated small minerals in the lava that did not melt in the original lava so actually were many millions of years old.)

Or they will claim that radiocarbon dating isn’t even used for dating dinosaur fossils … leaving out that radiocarbon dating can’t be applied to things that are more than ~50,000 years old.

Anyway, all that’s for another post. The purpose of this post is to point out that the point of science is to develop a model that can be applied to everything it attempts to describe. Gravity works the same on Earth as on the moon as in the center of a galaxy cluster. For the issue at-hand, YECs need to decide whether they believe in radiometric dating and its usable, or whether they don’t and so don’t use it.

Why Am I Talking About This?

In the news over the past week, yet another group of YECs have claimed to discover Noah’s Ark on top of Mt. Ararat in Turkey. There are many outlets for this story, but out of fun, I’ll link to the one over at FOX News. The relevance to radiometric dating? I’ll quote (emphasis mine):

“The group claims that carbon dating proves the relics are 4,800 years old, meaning they date to around the same time the ark was said to be afloat. Mt. Ararat has long been suspected as the final resting place of the craft by evangelicals and literalists hoping to validate biblical stories.”

Didja see that? Meanwhile, over at Answers in Genesis:

“All radiometric dating methods are based on assumptions about events that happened in the past. If the assumptions are accepted as true (as is typically done in the evolutionary dating processes), results can be biased toward a desired age. In the reported ages given in textbooks and other journals, these evolutionary assumptions have not been questioned, while results inconsistent with long ages have been censored.”

Or from an older Institute for Creation Research article:

“Creationists are not so much interested in debunking radiocarbon as we are in developing a proper understanding of it to answer many of our own questions regarding the past. At the present time it appears that the conventional radiocarbon dating technique is on relatively firm ground for dates which fall within the past 3,000 years. For periods of time prior to this, there are legitimate reasons to question the validity of the conventional results and seek for alternative interpretations.”

Or, a case of very special pleading from another ICR article:

“A ‘Back to Genesis’ way of thinking insists that the Flood of Noah’s day would have removed a great deal of the world’s carbon from the atmosphere and oceans, particularly as limestone (calcium carbonate) was precipitated. Once the Flood processes ceased, C-14 began a slow build-up to equilibrium with C-12—a build-up not yet complete. Thus carbon dating says nothing at all about millions of years, and often lacks accuracy even with historical specimens, denying as it does the truth of the great Flood. In reality, its measured disequilibrium points to just such a world-altering event, not many years ago.”

Final Thoughts

You can’t have it both ways. Or all four ways (I kinda lost count). Either (1) radiometric dating doesn’t work, (2) radiometric dating does work once you account for things that YECs have yet to really define, (3) it does work for the recent past to 3,000 years ago but not for anything before that, or (4) it works for everything made after the flood (as in the ark was built before the flood so can’t be dated with it).

What this all boils down to is the Inconsistency Fallacy, one I didn’t address in my series the last two months of 2009 on Logical Fallacies (but I do intend to return to that series later this year). The Inconsistency Fallacy is basically summarized as, “Multiple statements that contradict one another.” For example: “Statement A is true and B is true. Use one of these statements to prove the other is false.” Or, “Bill is younger than Jill, and Jill is younger than Charles. Charles is the oldest of the three.”

And that’s the case here. Either it’s valid, or it isn’t. You can’t use radiometric dating to claim the Bible is literally true to claim that radiometric dating doesn’t work.

April 10, 2010

An Active Venus? — Another Pre-Emptive Creationism Post


Introduction

A few weeks ago, I wrote a post about Saturn’s rings, in a preemptive attempt to address some recent research that I thought some young-Earth creationists (YECs) may use to assert their views. I am somewhat surprised that the three main sources I read for creationist stuff have been silent on it. Swing and a miss on my part.

Let’s see if my fledgeling psychic powers are better-tuned for this one. This past week, several news outlets were running the story that the planet Venus may have active volcanism, revealed by the ESA spacecraft Venus Express (ESA press release, NASA press release, and Science journal article (the last one requires a paid subscription)). Seems like a possible story that a YEC may latch onto, so here’s another preemptive post explaining the science so if there is a YEC response, I can dive right into it without the background info needing to be repeated.

About Venus

There is some basic information about Venus that’s relevant to this discussion. First, as most people know, Venus is the second known planet from the sun, residing about 71% as far from the sun as Earth does. Conveniently, and importantly for this post, Venus has a diameter that is 94.9% Earth’s diameter. However, since its overall density is less, its mass is 81.5% that of Earth’s.

The surface of Venus is shrouded from Earth in visible light, hidden by clouds so thick that the temperature is around 465 °C, and hence you often hear that the surface is hot enough to melt lead. The atmosphere is nearly 100 times as massive as Earth’s exerting 92 bars of pressure on the surface that is the equivalent of being under about 1 km of water. Now you may have an idea why it’s hard to build a spacecraft to land on it and survive long enough to do anything useful.

The other thing about its surface is that it has been imaged, just not in visible light. The spacecraft Magellan mapped nearly 100% of Venus’s surface and determined its topography when it orbited in 1990 through 1994. Among other things, the data showed that Venus has many volcanoes, and it only has about 1000 craters.

Now you may be wondering, “Why is he talking about craters? Is it because he studies them and just thought it would be fun to mention?” Well, yeah, I do study them, but they are also the ONLY way to tell relative geologic ages in the solar system since we lack any way to absolutely determine the ages (such as through biological means on Earth and radiometric dating on Earth and the Moon). In contrast to Venus having only 1000 craters, and nearly all of them larger than 5 km in diameter, means that Venus’ surface is very young. In contrast, the planet Mars has about 45,000 craters that are larger than 5 km in diameter.

Based on a lot of modeling, current estimates of Venus’ surface cratering age shows it to be about 700 million years old. Yes, that may seem old, but compared to the moon, Mars, and Mercury – the other large, non-Earth bodies in the inner solar system – Venus has the youngest overall surface. And the last paper to really study the distribution of craters on Venus shows that they are completely random, so it’s not just that half the planet’s surface is 1 billion years old and the other half is 500 million, but the whole surface is about 700 million years old.

Catastrophic Eruptions

The next question one may logically ask is how an entire planet with a surface area 90% that of Earth’s (95%^2) can be resurfaced? From the geologic evidence of massive volcanoes across the planet, the general consensus is that it was volcanic eruptions.

Let’s look at Venus, Earth, and Mars. Mars is only 45% the diameter of Earth, and its mass is only 10%. The analogy I like to give is that if you take a little cupcake and a big cake out of the oven at the same time, which is going to cool faster? This is why Mars has long been termed “geologically dead,” though it does show some pittance of active geology today — but none from internal heat sources.

In contrast, Earth has a lot of internal heat, and we see that every day in the form of volcanoes and undersea vents. Our heat drives plate tectonics, making earthquakes that have also been in the news a lot lately with Haiti, Chili, and Mexico. So while Earth is internally molten, our lithosphere (the region below the crust and above the mantle) is thin enough and fractured enough to let some of that heat out.

The thinking is that Venus has a lot of internal heat like Earth, but, it has a thicker lithosphere. That lithosphere under normal circumstances is simply too thick to let heat escape, so the heat stays trapped inside.

Now here’s another analogy: Let’s say you’re going to spend another lonely night in your 1-bedroom apartment, and even the cat doesn’t want to have anything to do with you. You’re going to watch a cheesy movie and don’t want to cook, so you go to the freezer and look through your few dozen frozen microwaveable dinners that you bought in bulk at Costco. You choose one and read the directions for lack of anything better to do. The directions state quite clearly: “PUNCTURE WRAPPING BEFORE MICROWAVING.” From past experience, you know that if you don’t, the heat will build up and explode in what means 10 minutes of messy clean up. But if you do puncture the wrapping, the steam can escape and it’s all good.

This is the same – albeit simplified – thing that happens with planets. Since Earth can release its heat, it doesn’t “explode.” With Venus, the thought is that since the lithosphere is thicker, the heat builds up until the molten rock finally forces its way out. When it does, the lithosphere cracks and planet-wide, catastrophic volcanism ensues. And the last time this happened – based on the craters – was around 700 million years ago.

Fascinating … What Does This Have to Do with the Press Release?

Good question, I’m glad you asked. Let’s get back on-topic. With a last massive planetary resurfacing 700 million years ago, one question has been, “Is this going to happen again?” Another is, “How often does this happen?” And the most relevant to this discussion, “Is there still some dribble of volcanism today?”

It’s that last question that Venus Express may have found evidence to answer in the affirmative. From the NASA press release: “For the first time, scientists have detected clear signs of recent lava flows on the surface of Venus. The observations reveal that volcanoes on Venus appeared to erupt between a few hundred years to 2.5 million years ago. This suggests the planet may still be geologically active, making Venus one of the few worlds in our solar system that has been volcanically active within the last 3 million years.”

I’m guessing they had to add “one of the few” because of Earth and Io.

Anyway, going off of the press release (I don’t have access to the Science article right now — I’ll update this later if needed when I get ahold of it), the researchers were able to study the mineralogy on three of Venus’ volcanoes. The mineralogy matches that on recent volcanic eruptions from some volcanoes on Earth, like Hawai’i. On Earth, the rock’s reaction with oxygen quickly changes the mineralogy, and hence the research strongly suggests that the flows are young enough to not have been modified. They suggest anywhere from a few hundred to 2.5 million years old.

This may change the picture that I outlined above of the catastrophic volcanism. In perhaps the more controversial part of the press release to me, they suggest that this could indicate the volcanism on Venus has been gradual throughout time – in a kind of steady state situation where localized events happen to resurface the area and cover a few craters, die down, and then happen elsewhere, but not covering enough to maintain the 700-million-year-old crater surface age. It’s a possibility, but at least to me they will need to show more evidence before I find it more convincing than the catastrophic scenario.

What’s this to Do with Young-Earth Creationism?

Venus has come up in the YEC literature before. I wrote one of my first blog posts on, “ Venus and the Battle of Uniformitarianism (A Creationist Argument).”

In this case, I am guessing that if some YEC person or institute chooses to use this to try to add evidence for their claims it will be along the lines of, “Since Venus has active volcanism today, it must have been created in the very recent past – 6000 years ago. Evolutionists/Darwinists/Evilutionists will have to completely change their thinking in order to reconcile an active Venus with an old-Earth.” Or something like that.

Final Thoughts

We’ll see if my budding psychic powers have been led astray again. I hope not, but we’ll see. Even if they have, hopefully I’ve given you enough information to find this press release interesting and have newfound interest in the field of planetary geology and geophysics.

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