Nemesis and Planet X: Can they be Ruled Out?

[Nereid]

The former is a hypothesis that originated with observations of (apparent) periodicity in the extinction record, and has had its share of fame and controversy; the latter began as an innocent follow-on to the discovery of Pluto ('that puny little thing, a planet??') but in the late 20th century was kidnapped by a tribe of anti-science Californians.

But can either be 'ruled out'? More precisely, in what regions of parameter space may such objects still lurk, awaiting discovery?

Of the many techniques that could be used to discover any such 'hidden perturbers' (lovely phrase, donchathink?), which are the most powerful (in principle)? I mean this in the sense of 'straight-forward application with today's technology, at modest cost, could put much improved constraints on the existence of such objects in vast realms of parameter space'.

 

[Andre]

Hi Nereid, long time no see. Happy New Year.

Richard Muller "invented" Nemesis based on both that extinction pattern and the perceived asteroid impact history of the moon derived from spherule research:

http://muller.lbl.gov/papers/Lunar_impacts_Nemesis.pdf

However, new scrutinized reseach shows a different cyclic extinction pattern (same author) of 62 million years instead of the previous 26 million years.


http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/03/10/MNGFIBN6PO1.DTL

http://www.baa.duke.edu/weillab/publications/fossilsmakewaves.pdf

Now check that this is about marine micro fossil extinctions and the last one seemed to have been 65 Mya

http://www.futurepundit.com/archives/002689.html

So a new extinction seems overdue or perhaps not and the Mid Pleistocene Stilostomella extinction has been overlooked?

http://jfr.geoscienceworld.org/cgi/content/abstract/32/3/274

Anyway, there seems to be no more reason for a 26 My orbit of Nemesis, making it chances of it's existence more remote.

 

[quantumcarl]

Nice thread Nereid!

Something else to consider... the Galactic Orbit model as it applies to the periodic extinctions of (most of) life on earth. Please excuse the long quote:

A Galactic Orbit Model for Periodic Mass Extinction



New Theory Explains Timing of Major Impacts and Extinction Events

Life on planet Earth has experienced 6 major and several minor extinction events over the past 620 million years. Statistical analyses suggest a periodic nature to these events. However, no model has been able to elegantly explain the apparent non-randomness in the data. A new astronomical model presented here, the Galactic Orbit model, shows a much stronger correlation with extinction and impact data (both craters and extraterrestrial geochemical signatures in Earth sediments) than previous models. It explains periodicity by invoking a 186 million-year galactic orbital period (corresponding to a galactic "year" for our solar system) with three discreet zones of high extinction for every trip around the galactic nucleus.

In recent years, two periodic extinction models have received the most attention in the scientific community and the media. The first is known as the Nemesis model and the second is the Galactic Plane transit model. Both involve a perturbation of Oort cloud comets, resulting in comet showers to the inner solar system. One or more of these comets then strike the Earth, causing catastrophic environmental changes and mass extinction of species.

The Nemesis model asserts that a somewhat massive solar companion gravitationally disrupts the Oort cloud at perihelion every 26 million years. However, such an object has not been found in spite of searches. Furthermore, an object with the necessary mass and orbital period is likely to have an unstable orbit. Passing stars would probably have stripped it away from our sun eons ago. The Galactic Plane transit model asserts that our solar system’s passage through the matter-rich galactic plane every 32 million years provides sufficient gravitational flux to disrupt Oort cloud comets. This idea is similar to "disk stripping" of globular clusters’ outer stars, also thought to occur due to passage through the galactic plane.Both of these models fail the predictions test. A group of extinctions should line up on 26 or 32 million year intervals. No such grouping is observed in the fossil record, although gaps of 26-32 million years are sometimes observed between extinctions.

The periodic nature of impacts and extinctions is displayed in detail on my educational map entitled:"A Correlated History of the Universe" by Pan Terra Inc. Notice the four largest probable impact events:(the K/T, P/Tr, O/S, Stu/V boundaries) are evenly spaced by ~186 million year intervals. The Galactic Orbit model implies that these four events occurred when our solar system passed through the most dangerous zone, or Zone-1. The impact/extinction data also suggests 2 minor Zones, also causing extinctions with a 186 million year period (just like Zone-1). Zone-2 transit follows Zone-1 transit by about 32 million years. Zone-3 follows Zone-2 by about 40 million years. After we get past Zone-3, there is a relatively quiet gap of 114 million years until the solar system returns to Zone-1.

An analogue to this model would be the annual meteor showers seen from Earth. The comet debris trails that cause the showers are basically fixed with respect to Earth's orbit. We hit them the same time every year like clockwork as we orbit the sun. On the galactic scale, the time required for our solar system to make a lap around the galactic nucleus has been estimated to be in the range of 200-250 million years. The Galactic Orbit model suggests that 186 million years might be the effective period for our solar system. Perhaps we encounter stationary zones or features (relative to our galactic orbit) where gravitational flux or possibly shockwaves cause Oort cloud comets to venture into the inner solar system in large numbers.

Some candidate agents include spiral arms, giant molecular clouds, interactions between our galaxy and others, rapid bursts of star formation, supernovae generating shockwaves, etc. There may be multiple causative agents in this model. The 186 million year period and the three dangerous zones are the key ideas.The Galactic Orbit model might explain why the 26-32 million year periodicity ideas became popular. What researchers may actually have been detecting with statistical analyses are the stagger times (or sums and multiples thereof) between the three galactic danger zones.

Some predictions of the Galactic Orbit model can be tested. We should see a repeating pattern of Zone-1, 32 million year gap, Zone-2, 40 million year gap, Zone-3, 114 million year gap, then back to Zone-1. Research indicates a strong correlation between the predictions, the impact data and the extinction record. Also successfully predicted are the big gaps without mass extinction, which the other theories can’t explain. Curiously, the Earth’s magnetic field seems to stabilize for extended periods during this long 114 million year quiescent gap, as suggested by the Kiaman superchron preceeding the P/Tr and the Cretaceous magnetic quiet zone preceeding the K/T.

The impact and extinction data for Earth is a complex natural history puzzle. The Galactic Orbit model succeeds in predicting all of the major impact/extinction events as well as the long, relatively quiet times in between. One additional prediction is for an extraterrestrial signature to be found in rocks deposited during the Silurian/Devonian boundary interval. All of the other predicted times have strong statistical correlation with mass extinction, craters, and/or extraterrestrial geochemical signatures of various types. Events like the Jurassic/Cretaceous boundary (where craters and moderate extinction are present but the timing does not fit with the predictions of the model) would be caused by other culprits including random comets, random large asteroids, random gravitational effects from passing massive bodies or shockwaves/radiation from proximal exploding bodies(supernovae).

The question arises, where are we are now? Our solar system will hit the Zone-3 peak in about 7 million years. Given the cosmic scales and dating uncertainties, one might say our foot is at the door of Zone-3. In terms of galactic geography, we are beginning to enter the inner part of the Orion spiral arm. The last time we were "here", an 80km diameter crater (Puchezh-Katunki in Russia) greeted Earth and some of the dinosaur groups of that time had a noticeably bad year. On the Zone-3 visit previous to that (186 million years earlier), multiple craters and late Devonian mass extinctions were the result, perhaps the fourth or fifth worst extinction known from the fossil record. The Galactic Orbit model predicts 365 million years ago for the danger peak. We actually have evidence for two discreet extinction events during this interval, the Frasnian/Fammenian at ~367mya and the Devonian/Carboniferous at ~360mya. The good news is that the ultimate killer, Zone-1, is still 120 million years away and may be correlated to our solar system passing through the Crux spiral arm of the Milky Way.

If this model or something like it is shown to be useful, it might lead astronomers to examine our solar system’s local neighborhood in more detail, along with a closer look at the long-period comet data. It might be possible to determine favored directions from which comets might be emanating and focus more observational assets toward those regions.

In the course of my research, I occasionally discover something that merits additional publishing efforts to properly disseminate the discovery through the scientific community. I am seeking collaboration with interested parties who publish in the area of galactic dynamics, with the goal of refining and publishing the Galactic Orbit model in an appropriate, peer-reviewed publication.

References: " A Correlated History of the Universe" by Pan Terra Inc., © 2002

 

[Andre]

However, new scrutinized reseach shows a different cyclic extinction pattern (same author) of 62 million years

The Galactic Orbit model suggests that 186 million years might be the effective period for our solar system

186:62=3.0000. Curious.

 

[Nereid]

Interesting comments, but not (apparently) directly addressing my question (Of the many techniques that could be used to discover any such 'hidden perturbers' (lovely phrase, donchathink?), which are the most powerful (in principle)?)

That an examination of the fossil record of mass extinctions is a method for such discovery, I'd comment that it is a particularly poor one, for at least the following reasons:

-> mass extinctions in the fossil record (difficult to determine in any case) leave - in the fossil record itself - only the most indistinct of signals concerning Nemesis (or other causes of periodic bombardment) - the fossils themselves don't say "bombardment" or "plate tectonics" or "methane burps" or "flood vulcanism", or ...

-> periodic mass extinctions tell us nothing of where 'Nemesis' is (or even what it is)

But perhaps you meant to say something like "a full analysis of the rocks at the times of identified mass extinctions"? Even allowing this, I don't feel it's a particularly powerful method, if only because there are so many links in the 'chain of evidence' that need to be locked solid before the nature of any 'hidden perturber' could be established.

In any case, isn't it so that there is very little in the rocks indicating KT-style impacts (no Ir spikes, no shocked quartz, precious few craters, ...)? IIRC, other than for the KT impactor, there's very little that relates any observed mass extinction to such evidence, with a sufficiently close temporal correspondence (back to the late Cambrian, there's only one, n'est pas?)

 

[Garth]

True Nereid, mass extinctions are very ambiguous.

Some time ago it was suggested (In Monthy Notices RAS but I've lost the reference) that the periodicity of such was about 32Myrs, so the dinosaurs suffered from one three cycles ago, with the last about 1Myr ago at the time of the onset of the Ice Ages.

What intrigued me about this figure was that it is also the period of an Oort comet with SMA of 10⁵ AU. Coincidence or Nemesis?

Garth

 

[Andre]

I have no answer to Nereids question but, then again how big are the chances of Nemesis existing in the 26My orbit when it's supposed to explain the cycles in biodiversity.
Would it help if we look at this overview of our current understanding of major and minor extinctions, bolide impacts and trap volcanism?

Would an orbit of 32 My still be stable enough?

 

[quantumcarl]

Interesting comments, but not (apparently) directly addressing my question (Of the many techniques that could be used to discover any such 'hidden perturbers' (lovely phrase, donchathink?), which are the most powerful (in principle)?)
That an examination of the fossil record of mass extinctions is a method for such discovery, I'd comment that it is a particularly poor one, for at least the following reasons:
-> mass extinctions in the fossil record (difficult to determine in any case) leave - in the fossil record itself - only the most indistinct of signals concerning Nemesis (or other causes of periodic bombardment) - the fossils themselves don't say "bombardment" or "plate tectonics" or "methane burps" or "flood vulcanism", or ...
-> periodic mass extinctions tell us nothing of where 'Nemesis' is (or even what it is)
But perhaps you meant to say something like "a full analysis of the rocks at the times of identified mass extinctions"? Even allowing this, I don't feel it's a particularly powerful method, if only because there are so many links in the 'chain of evidence' that need to be locked solid before the nature of any 'hidden perturber' could be established.
In any case, isn't it so that there is very little in the rocks indicating KT-style impacts (no Ir spikes, no shocked quartz, precious few craters, ...)? IIRC, other than for the KT impactor, there's very little that relates any observed mass extinction to such evidence, with a sufficiently close temporal correspondence (back to the late Cambrian, there's only one, n'est pas?)

Happy 2006... here is the link to where I scooped the "Galactic Model" of extinction events:

http://www.wmnh.com/wmgschuw.htm

Thanks to Nereid I may not get sued for copyright infringement... and if I do I will try to hold the court in appeal for 62 million years.

The author of that quote I gave is selling his idea and you can put it in a shopping cart. He is also looking for similar ideas and people who might want to write about them.

I have seen mention of a galactic model to explain periodic near extinction in other texts and contexts as well. I will search these out of the library. I think they're recent references and may even point back to the source I have linked above.

I do remember that the model in the book in question showed an occillation that occurs where our part of the gallaxy, (aproximal position on a spiral arm) travels in and out of some areas that are denser with stars and debri than others as the galaxy spirals.

It is difficult to prove the theory because we can't compare signature trace deposits of elements to original elements from the area our solar system has alledgedly passed through. This is because we are not in any of the areas at this time and supposedly won't be for another few million years.

There are stratified layers of the Earth that display changes due to radiation and so forth but, as the article says, the origin of these readings could be any number of events.

The debris from the 65mya (astroid?) event may hold an answer to Nereid's question. Perhaps using spectographic telescopy to find a match to the composition of such debris would tell us where we're headed and what's in store for the humans that may or may not be on Earth when Earth gets there.

 

[WarrenPlatts]

I didn't know that Jack Sepkowski had passed on. I took paleontology from him when he and Dave Raup first published their hypothesis. Last I saw him he was in strapping good health. Only age 50. . . . . . .

 

[Nereid]

I didn't know that Jack Sepkowski had passed on. I took paleontology from him when he and Dave Raup first published their hypothesis. Last I saw him he was in strapping good health. Only age 50. . . . . . .

You must have seen him not long before the heart attack which killed him, in 1999 - http://www.findarticles.com/p/articles/mi_qa3790/is_199909/ai_n8871109".

 

[Nereid]

So searching the fossil record - even combined with looking for craters, Ir spikes, shocked quartz, etc - isn't a very powerful way to find (or rule out) a Nemesis (or Planet X).

How about a survey of parallaxes? How powerful a technique would that be?
The most recent, and perhaps best known, such survey was http://sci.esa.int/science-e/www/area/index.cfm?fareaid=20" ; what regions of parameter space* do the results from this mission leave open for a Nemesis (both the HIP and Tycho catalogues)?

*let's assume any such unseen companion is in an orbit around (or with, if you prefer) the Sun, and has been in such an orbit for at least a billion years.

 

[Garth]

So searching the fossil record - even combined with looking for craters, Ir spikes, shocked quartz, etc - isn't a very powerful way to find (or rule out) a Nemesis (or Planet X).

How about a survey of parallaxes? How powerful a technique would that be?
The most recent, and perhaps best known, such survey was http://sci.esa.int/science-e/www/area/index.cfm?fareaid=20" ; what regions of parameter space* do the results from this mission leave open for a Nemesis (both the HIP and Tycho catalogues)?

*let's assume any such unseen companion is in an orbit around (or with, if you prefer) the Sun, and has been in such an orbit for at least a billion years.

Searching the IRAS data might have proved more fruitful, only it didn't find Nemesis. Astrometric micro-lensing might also prove fruitful: Astrometric Microlensing Constraints on a Massive Body in the Outer Solar System with Gaia but I think if a brown dwarf was out there we would have found it in the IR by now.

Garth

 

[WarrenPlatts]

You must have seen him not long before the heart attack which killed him, in 1999 - http://www.findarticles.com/p/articles/mi_qa3790/is_199909/ai_n8871109".

Wow, thanks for the link. Actually, the last time I saw Jack, and I'm really dating myself now, was back in the mid-1980's. I also went on one of those spring break field trips. In 1985 we went to the Turks and Caicos. Jack was a nice guy. Once the sea was pretty rough, and I was having a hard time making it back to shore. Jack didn't have to help me, but he was right there in case I needed it. His legacy lives on though.

 

[Nereid]

I have no answer to Nereids question but, then again how big are the chances of Nemesis existing in the 26My orbit when it's supposed to explain the cycles in biodiversity.
Would it help if we look at this overview of our current understanding of major and minor extinctions, bolide impacts and trap volcanism?
Would an orbit of 32 My still be stable enough?

Thanks Andre.

Is there some explanation to go with this summary? For example, what's the difference between 'CRATERS - CLOSE' and 'Crater - other'? And what are 'IMPACTS - NO CRATER'?

Also, do you know if anyone has a chart of (well documented) iridium spikes, shocked quartz, tektites, etc?

Finally, what is the cratering history on the Moon, over the last ~600 million years? Especially of large (>50km) craters.

PS I did some surfing on the 'Bedout/PT?' crater - it sure isn't a Chicxulub, is it!

 

[Andre]

Is there some explanation to go with this summary? For example, what's the difference between 'CRATERS - CLOSE' and 'Crater - other'? And what are 'IMPACTS - NO CRATER'?

Sorry, it was a rush post. But here is the source with great links, like http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-4H9YCC8-2&_coverDate=11%2F15%2F2005&_alid=329050930&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5801&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9a2d1584bf5503c2f8977d02ae9d0922

It appears that the "Close" refers to a geologic boundary associated with extinctions.

Also, do you know if anyone has a chart of (well documented) iridium spikes, shocked quartz, tektites, etc?

If it exists, it would probably be http://md1.csa.com/factsheets/georef-set-c.php

But I haven't been exploring there since "To google" hasn't earned its status as verb for nothing.

Finally, what is the cratering history on the Moon, over the last ~600 million years? Especially of large (>50km) craters.

http://www.lbl.gov/Science-Articles/Archive/lunar-spherule.html about the dating of a few lunar spherules (also on the former chart) shows a market increase of impacts around 400 Mya was one of the two incentives for the Nemisis hypothesis of Richard Muller.

Not sure if my former link still works.

The real biggies appear to be rather old, ~3,85 - 3,9 Bya according to http://www.unm.edu/~abqtom/observing_the_moon.htm/

Indeed it's rather unlikely that the bedout event went by unnoticed.


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