Rare Rock from Jupiter and Beyond Killed the Dinosaurs

What? The dinosaurs are dead? No more Jurassic Park sequels?

Of course we all know the dinosaurs haven’t been around for quite some time. For 160 million years they dominated life on Earth then suddenly disappeared from the fossil record. For the last 200 years scientists have been weaving together tiny threads of evidence to discover exactly what happened.

A recently-published report details the efforts by a group of scientists to identify the culprit responsible for killing the dinosaurs. That’s not really news; there are more theories than dinosaurs. Many similar investigations have been conducted over the years. This time around however, the research also attempts to identify the unknown object’s origin by taking us on a wild detour through the outer reaches of the solar system.

The reports that I critique typically have three things in common: the research involves something that does not need to be studied; it employs methodology unlikely to yield useful data; and a 3-D printer is used as a toy. Two of these criteria were satisfied here. To this research team’s credit, a 3-D printer was not abused.

The subject of this investigation is actually valid, as scientists are still looking to answer many questions about that great extinction. But the evidence itself seems to be of questionable value, not solidly supporting the researchers’ conclusions, and the reporting just makes it worse. A good reporter should be able to identify ambiguities, contradictions and holes, and seek to clarify the report instead of contributing to the confusion. That did not happen here.

For a little background on the subject of today’s report, we have to journey back to a time when dinosaurs ruled the Earth.

Our story begins 66 million years ago when a massive, as yet unidentified object slams into the Earth, setting into motion a long-term global climate catastrophe that results in the extinction of over 70% of all plant and animal species, including all of the non-avian dinosaurs. That is generally accepted as fact, and it is supported by abundant evidence. Although the object in question has never been discovered or positively identified, most scientists agree that the evidence points to an asteroid.

That extinction, now known as the Cretaceous-Paleogene Extinction, is the most recent of the five known major extinction events that have occurred since life began here more than 3.5 billion years ago.

Prevailing evidence suggests that the impact of the unknown object left a huge crater in the Gulf of Mexico near what is now Chicxulub, Mexico. That impact threw into the atmosphere hundreds of billions of tons of water, water vapor, rocks and dust, much of which remained suspended for many years. It drifted globally, and eventually settled to the surface all over the world.

How do we know all of that? For that answer we must return to a much more recent time in history.

In the 1970s, the chemical element iridium was found to be present in the 66-million-year-old geologic layer that separates the older Cretaceous era (dinosaurs) from the more recent Paleogene era (no dinosaurs). Iridium is very rare on Earth, but it is known to be abundant in some asteroids.

That discovery led to the 20-year search for the asteroid presumed to have been responsible for the increased levels of iridium in that layer.

That search eventually brought researchers to Mexico, where unusually high levels of iridium had been detected in the vicinity of the Yucatan Peninsula. In the early 1990s, extensive surveying in the area led to the discovery and subsequent dating of the Chicxulub Crater, the center of which lies off the coast of Yucatan in the Gulf of Mexico. It has since been considered to be the final resting place of the asteroid that is responsible for the iridium discovered in the Cretaceous-Paleogene layer, making that asteroid the prime suspect in the environmental disaster which ultimately led to the dinosaurs’ demise.

That seemed settled. But science is never finished.

30 years later, in 2021, a published report on some new research sought to shift the blame to a colliding comet, rather than the more likely asteroid strike. That research relied primarily on reinterpreting existing data rather than any discoveries of new evidence. Being more of a second opinion, the conclusion implicating a comet was largely dismissed by the scientific community.

Now, in 2024, a new group of researchers has again attempted to determine the identity of the mystery object, known by scientists as the Chicxulub Impactor. They apparently took that 2021 comet theory seriously enough that they felt it had to be refuted.

The published reporting on this current research is what I will autopsy here.

Like the decades-old iridium anomaly, this research is based upon the presence of a rare-earth element that was also detected in higher levels at the Cretaceous-Paleogene division. The research seeks to again identify an asteroid as the source of that element, and link that asteroid to the Chicxulub Crater.

Going one step beyond identifying the object and its impact location, though, the research also attempts to pinpoint its origin. Where in outer space did it come from? That is a lofty endeavor.

This is the title of the report as published on Space.com: “Dinosaur-killing asteroid was a rare rock from beyond Jupiter, new study reveals.”

That caught my attention and piqued my curiosity. We were already fairly certain that the rock was an asteroid, due in no small part to the decades-old iridium discovery and subsequent research. That’s not news. But how can scientists now determine the origin of the asteroid? That is news to me.

I still don’t know, nor do they, because the text of the story quickly contradicts the asteroid’s origin alluded to in the title. The story begins by telling us that the signature element they traced comes from asteroids that lie between the orbits of Mars and Jupiter. ‘Between Mars and Jupiter’ is not ‘beyond Jupiter’ by anyone’s calculation, unless you’re reporting from Saturn…or beyond.

Adding to the confusion was another puzzling statement: “The space rock that wiped out the dinosaurs 66 million years ago was a rare strike from an asteroid beyond Jupiter.”

That is an even wilder tale, a rare strike indeed. That, my friend, is science fiction.

An asteroid ‘beyond Jupiter’ is just that, an asteroid that is located beyond Jupiter. That can only be interpreted as a location out past the orbits of Mars and Jupiter—presumably from Earth’s perspective—at the time of the impact.

How can a rock that is out beyond Jupiter crash into Earth, unless Earth traveled out to meet it?

I don’t believe that happened. There is no evidence suggesting that Earth had at any time taken a wild vacation, however short, away from its current orbit.

We can safely rule out an object ‘beyond Jupiter.’ So, we must assume the writer intended to say ‘from beyond Jupiter,’ as she did elsewhere in the article. If that is true, it means the asteroid traveled here. Although that is not out of the question, a question still remains: “did the object originate from beyond Jupiter’s orbit, as is stated, or was it actually from between the orbits of Mars and Jupiter, which is also stated?” A vast distance separates the two areas.

In our solar system the majority of asteroids reside in the aptly-named main asteroid belt situated between Mars and Jupiter. A much smaller population of asteroids exists beyond Jupiter, between the orbits of Jupiter and Saturn. And there are those rare nomads that pass through from somewhere outside our solar system.

There are millions of asteroids, and any of them can be pushed or pulled from their orbits by other asteroids, and sent on a collision course with Earth. While most are too small to be a serious threat, there are thousands that are large enough to cause catastrophic damage if they struck our planet.

They have not made a conclusive case for the origin of the presumed asteroid, though clarity may have been lost in translation. Maybe there is a better case to be made for the identification of the object itself, and its possible link to the Chicxulub Crater.

Scientists recently digging in Western Europe discovered that, besides iridium, another rare element was present in the Cretaceous-Paleogene division.

This time, that rare mineral is ruthenium, a chemical element that is likely found throughout the universe in second and third-generation star systems.

First generation stars would have been formed from only hydrogen, helium, and a tiny amount of lithium, the only elements created in the Big Bang. The nuclear fusion powering those stars formed heavier elements, iron being the limit. Heavier elements could only be created when that star died, collapsed and then exploded into a supernova. The tremendous energy involved allowed all the heavier elements to form. Those were now available when the second-generation stars formed from the supernova’s dust. Our own sun is thought to be at least a third-generation star, formed from the elements from the demise of countless other earlier-generation stars. All the planets in our solar system formed from the same dust.

Ruthenium is probably as common on Earth as anywhere in the cosmos, but not near the surface. It is a very heavy element, and during Earth’s more fluid early stages, gravity pulled much of it deeper into the planet. Ruthenium is apparently common in some asteroids, especially in those from the region of space that is in question, although the region in question is … in question.

Ruthenium’s presence in the 66-million-year-old layer is the entire basis of this research. It is the single reason for the scientist’s conclusions that it was an asteroid rather than a comet that left the crater, and it is the only thing suggesting that the asteroid came from out near Jupiter (or Mars, or wherever).

But at least two problems exist with that assertion. First, ruthenium, though rare near the surface, is found on Earth naturally, in deposits in North and South America, as well as Asia and Africa, and up to 30 tons is extracted every year for commercial use (contrasted to only 7 tons of iridium extracted).

So apparently it’s not that difficult to access with a little digging, and the Chicxulub Impactor could have penetrated several miles into the Earth and excavated billions of tons of ruthenium-bearing crust from deeper layers. There is also more ruthenium than iridium naturally, making it a less reliable indicator.

And second, though attempting to tie the ruthenium to the Chicxulub Crater, there was no mention of any ruthenium being found at the crater. If you recall, iridium was found at the crater in unusually high levels, seemingly linking it to the iridium in the layer.

If that evidence was mentioned in the paper, it didn’t make it to the reporting.

The crater today is only about a half-mile deep, and although on impact the asteroid is thought to have initially penetrated up to 12 miles deep, the material that was not launched into the atmosphere fell back into the hole immediately after the impact. Most remnants of the impacting object would have been buried very deeply in the Earth’s crust.

There is no hard evidence in this study that the ruthenium came from a comet, an asteroid, or was simply churned up from our own planet’s crust and scattered about with the rest of the debris from the impact.

The report seeks to identify specific ruthenium isotopes as a “genetic fingerprint.” There were no genetics of course, because the asteroid was not a living thing, and there were no fingerprints. I will dismiss that characterization as a literary metaphor, although there is nothing else literary in the reporting.

Ruthenium occur naturally on Earth, so placing the blame on a ruthenium-bearing asteroid is like convicting a human suspect simply because he has fingerprints and genes.

Furthermore, the report also states, “The Chicxulub crater is the only known impact site on Earth made by an outer solar system asteroid.”

If that’s the case, if it is the only one, then how do they know asteroids from that region in space contain ruthenium? We would have nothing to compare it to. In turn, how would we know that’s the origin of the suspected object?

I’m so glad you asked, because, “The researchers compared the results to samples from other asteroid impact sites in South Africa, Canada and Russia.”

But wait, didn’t they just say there were no other known impact sites? On one hand, there are no other known impact sites of objects from that region of space. On the other hand there are other impact sites all over the world made by objects from that region of space. That sounds contradictory because it is.

They exist and do not exist simultaneously. Apparently they can have it both ways. I don’t think that is what Erwin Schrödinger had in mind.

There is one final, likely-meaningless-but-baffling contradiction in this report: the size of the crater itself.

The size is described as being 90 miles wide in one paragraph, and 125 mile wide in another. That is nearly a 40% discrepancy, and there is no explanation given for the different measurements.

To be fair, the actual size of the crater likely has no bearing on the origin or identity of the object. But why are two dimensions given? A discrepancy like that leads to a head-scratching that throws all other evidence into question. It was that one glaring detail that prompted me to examine the report more closely in the first place. I did not set out to pick it apart. In fact, I did not pick it apart. It simply fell apart.

Summing up, my own conclusions are understandably no less messy than the published reporting.

The impacting object left a crater that is either 90 or 125 miles across. Most sources describe the diameter as being “about 120 miles.” Pick one.

Scientists found an element in a 66-million-year-old geologic layer in Europe that they assert came from an asteroid from a specific region in space. But that element is also found on Earth, and it could have been churned up from our own planet’s depths, to be eventually deposited in Europe.

They say they know that element exists on asteroids from a specific region of space, but it’s not at all clear how they know that because that region is variously described in the reporting as being between Jupiter and Mars, or beyond Jupiter.

That is a discrepancy of at least 350 million miles, and it could be over a half-billion, encompassing two different asteroid belts. In fact, except for the Sun and 4 inner planets, the entire universe is beyond Jupiter’s orbit from Earth’s perspective.

They contend the element matches evidence from other impact sites of meteors from that region of space, even though they also state there are no other impact sites from that region of space.

But, and this is a big but, there is no mention of any ruthenium detected at or near the Chicxulub Crater, the presumed resting place of the suspected asteroid. Was it overlooked in the research or just left out of the report? That is a significant detail to omit. Without it, there is no link to the ruthenium found in the Cretaceous-Paleogene boundary. They will need to find another large 66-million-year-old crater.

With or without the link to the crater, though, any results are inconclusive. There was nothing proved or disproved. We got nowhere with our pointless journey out beyond Jupiter and back, but we enjoyed a lovely trip back in time to visit the dinosaurs on the day that sealed their fate.

Compound contradictions riddle this report and don’t make for a believable, or an easy-to-read report on a scientific paper. Omissions can suggest deceit or simple carelessness. Some of the problems are certainly based upon the reporting, but there are also problems with the science.

Can we expect the scientist’s own conclusions to be less ambiguous than the reporting? Prepare to be amazed.

In his closing remarks, the lead scientist asserted that his research found that a comet was “absolutely ruled out” as the dinosaur killer, but carefully added that “we can’t prove it.”

Asserted and contradicted in the same paragraph. If he can’t prove it, it can’t be ruled out, rendering this entire adventure inconclusive.

Those closing remarks by the scientist himself beautifully summarize the entire project as well as the reporting. I am again left wondering how papers like this get published in a scientific journal, or even as an article in the regular news. Do editors still read articles before publication? But I won’t ask that.

Here is my question for the researchers: Now that you are pretty sure that it was a rock, and you think you know where it came from, can you now check those genetic fingerprints to determine who threw it?

After all these years, the dinosaurs’ descendants deserve some closure.

Scott Wright © 2024

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