<p>There was japanese research into nebula winters, to find correlation of weather records with starbusts, dark bok clouds and supernovae:</p>

<p><a href="https://i.sstatic.net/M2JMp.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/M2JMp.jpg" alt="enter image description here"></a></p>

<p><a href="https://www.sciencedirect.com/science/article/pii/S1342937X13001597" rel="nofollow noreferrer">research reference</a></p>

<p>A global winter caused by a proto-stellar clouds, called bok globules, is possible too, because there may be 100 times more of them than we can see, they are abot 1ly diameter and 2-50 solar masses, completely dark. Perhaps they would dim the sun by at least 10-40 percent. 
<a href="https://i.sstatic.net/F1myA.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/F1myA.jpg" alt="enter image description here"></a></p>

<p>You can also find a document that regroups current research for Nebula Winters, corresponding to image 1. the geology evidence is the following:</p>

<p>Bodiselitsch et al. (2005) found iridium anomalies at the base of all cap carbonates both after
the Marinoan and Sturtian glaciations; iridium and other platinum-group elements are typical
proxies for extraterrestrial (including exosolar) materials and are much more abundant than in
the Earth’s upper mantle and crust. These authors interpreted the anomalies to be the product of
the rapid accumulation of extraterrestrial material once trapped in the surface ice and later
transported to the ocean floor via the melting of the ice at the end of the glaciation.
Nevertheless, the excursion of iridium may also reflect the enhanced flux of extraterrestrial
material due to an encounter with a nebula.
Moreover, 244Pu is expected to remain in the Fe/Mn crusts of interest. Fields et al. (2005)
estimated the 244Pu production by a supernova explosion to approximately 0.9 ×10-7
solar
masses. The expected flux of the 244Pu at the Earth is approximately 10-16 kg m-2
yr-1
. A
significant amount (0.1 Bq m-2
) of the accreted 244Pu remains in the sedimentary rocks, even
considering the half-life of 244Pu (80 Myr).
The existence of abundant 100-μm spherical iron balls in pelagic sediments is also possible
direct evidence. For example, Miono et al. (1993) argued that the spherules accumulate in
Paleozoic-Mesozoic bedded cherts. These spherules are generally believed to originate from 
25
micro-meteorites. The nebula winter model can be tested by similar but further advanced
investigations, including the analysis of the abundance of the isotopes and platinum family
elements of the minerals separated from spherules in the pelagic sediments, detailing their
exosolar nature. In addition, mineralogical investigations on the ages, the abundances of
platinum family elements, and the isotope ratios of the minerals of the exosolar grains in the
pelagic sediments at that time, will clarify the influence of the galactic environment on the
natural history of the Earth.</p>

<p>The theory is supported by time correlation, which is fairly close to starburts, which occur every 100Ma.</p>

<p>Specific evidence of historical astronomical events require the presence of supernovae elements, i.e. Iridium, in rocks from snowball times. </p>

<p>Other reasons for the Cambrian explosion are the edvent of bilateral animals, 600Ma, the last snowball event from 630Ma, PH and oxygen instability in the ocean, algea blooms. I found this pic which gives an idea of the oxygen concentrations from the cambrian: <a href="https://i.sstatic.net/tB1TL.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/tB1TL.jpg" alt="enter image description here"></a></p>

CC BY-SA 4.0
2018-08-28T16:57:32.840Z
What is the source of these plots? What are the error bars?
Anders Sandberg
CC BY-SA 4.0
2018-08-28T17:00:03.383Z
Downvoted for a complete lack of references.
David Hammen
CC BY-SA 4.0
2018-08-28T17:01:46.167Z
The first graph looks a bit suspect. The very deep Marinoan glaciation is typically included in the Cryogenian (look at the name) rather than in the Ediacarian.
David Hammen
CC BY-SA 4.0
2018-08-29T03:47:29.490Z
https://www.sciencedirect.com/science/article/pii/S1342937X13001597  and http://www.luckysci.com/2014/06/did-a-starburst-cause-earth-to-get-buried-in-kilometers-of-snow/
bandybabboon
CC BY-SA 4.0
2018-08-29T03:58:43.023Z
reference added.
bandybabboon
CC BY-SA 4.0
2018-09-30T01:26:19.367Z
https://www.youtube.com/watch?v=nVWy0bB2bVk&t=405s

So its possible for it to cause a mass extinction, but simultaneously not possible to cause mass mutations?  i think some troll is doing the downvoting.
Anthony Bachler
CC BY-SA 4.0
2024-09-18T06:13:22.880Z
https://astronomy.stackexchange.com/questions/27862/how-dark-would-the-sun-become-if-we-traversed-a-bok-globule Please delete at least the paragraph about Bok globules or provide references.
ProfRob
CC BY-SA 4.0
2018-08-28T12:53:04.843Z
2018-10-02T08:41:58.527Z
2018-10-02T08:41:58.527Z
bandybabboon
<p>Are there any known major events around the 50-60 million years preceding the cambrian explosion that could explain the sudden increase in biodiversity?  Specifically a supernova, or active galactic center either in the milky way or some other nearby galaxy?</p>

CC BY-SA 4.0
2018-08-28T00:40:16.090Z
Hard to see why any such event would trigger the Cambrian Explosion.  Explanations I'm aware of are generally related to the complex climate, ecosystem and chemistry of Earth as it developed reaching various critical points e.g. the concentrations of microorganisms and/or chemicals.
StephenG - Help Ukraine
CC BY-SA 4.0
2018-08-28T00:46:48.020Z
@StephenG - I agree. I have posted an answer below saying that astronomical events have little to no effect on our planet.
MystaryPi
CC BY-SA 4.0
2018-08-28T16:52:57.637Z
@StephenG - I suspect the question refers to the Ediacarian explosion (aka the Avalon explosion), circa 575 Mya, rather than to the Cambrian explosion, circa 541 Mya.
David Hammen
CC BY-SA 4.0
2018-08-28T17:33:09.247Z
Complex life happened 33 million years prior to the Cambrian explosion. Life was quite simple up to the Ediacarian. About 2/3 way in to the Ediacarian, life got considerably more complex (multi-celled animals and plants), and did so rather quickly. This early complex life may well have been its own undoing, with the first mass extinction occurring at the Ediacarian / Cambrian boundary.  While it may have well been its own undoing, that early complex life most likely also formed the seed for the even greater Cambrian explosion. No external event was needed.
David Hammen
CC BY-SA 4.0
2018-08-28T17:34:55.953Z
I have found multiple references, but don't have time to write them into an answer. The key reference: [Biotic replacement and mass extinction of the Ediacara biota](http://rspb.royalsocietypublishing.org/content/282/1814/20151003) (open source).
David Hammen
CC BY-SA 4.0
2018-09-24T17:37:10.840Z
The reason I asked for the 50-60 million years prior is because the sudden increase in biodiversity began then, it peaked later, but in the context of exploring whether it was a major global mutagenic event, I presume the trigger would be close to the start of the sudden increase not the peak.
Now the level of radiation would not have to be a bazillion times higher, any significant increase in background radiation would suffice.
Anthony Bachler
<astrophysics>
Candidate major astronomical events circa 600-541 mya?
Anthony Bachler
# Candidate major astronomical events circa 600-541 mya?

(Asked by: username_0 on 2018-08-28)

Are there any known major events around the 50-60 million years preceding the cambrian explosion that could explain the sudden increase in biodiversity? Specifically a supernova, or active galactic center either in the milky way or some other nearby galaxy?

**Tags:** astrophysics
> **Comments:**
> **username_1**: Hard to see why any such event would trigger the Cambrian Explosion.  Explanations I'm aware of are generally related to the complex climate, ecosystem and chemistry of Earth as it developed reaching various critical points e.g. the concentrations of microorganisms and/or chemicals.  
> **username_2**: @StephenG - I agree. I have posted an answer below saying that astronomical events have little to no effect on our planet.  
> **username_3**: @StephenG - I suspect the question refers to the Ediacarian explosion (aka the Avalon explosion), circa 575 Mya, rather than to the Cambrian explosion, circa 541 Mya.  
> **username_3**: Complex life happened 33 million years prior to the Cambrian explosion. Life was quite simple up to the Ediacarian. About 2/3 way in to the Ediacarian, life got considerably more complex (multi-celled animals and plants), and did so rather quickly. This early complex life may well have been its own undoing, with the first mass extinction occurring at the Ediacarian / Cambrian boundary.  While it may have well been its own undoing, that early complex life most likely also formed the seed for the even greater Cambrian explosion. No external event was needed.  
> **username_3**: I have found multiple references, but don't have time to write them into an answer. The key reference: [Biotic replacement and mass extinction of the Ediacara biota](http://rspb.royalsocietypublishing.org/content/282/1814/20151003) (open source).  
> **username_0**: The reason I asked for the 50-60 million years prior is because the sudden increase in biodiversity began then, it peaked later, but in the context of exploring whether it was a major global mutagenic event, I presume the trigger would be close to the start of the sudden increase not the peak. Now the level of radiation would not have to be a bazillion times higher, any significant increase in background radiation would suffice.  

---

## 1 answers

### Answer by username_4 on 2018-08-28. Score: 1

There was japanese research into nebula winters, to find correlation of weather records with starbusts, dark bok clouds and supernovae:

[![enter image description here](https://i.sstatic.net/M2JMp.jpg)](https://i.sstatic.net/M2JMp.jpg)

[research reference](https://www.sciencedirect.com/science/article/pii/S1342937X13001597)

A global winter caused by a proto-stellar clouds, called bok globules, is possible too, because there may be 100 times more of them than we can see, they are abot 1ly diameter and 2-50 solar masses, completely dark. Perhaps they would dim the sun by at least 10-40 percent.
[![enter image description here](https://i.sstatic.net/F1myA.jpg)](https://i.sstatic.net/F1myA.jpg)

You can also find a document that regroups current research for Nebula Winters, corresponding to image 1. the geology evidence is the following:

Bodiselitsch et al. (2005) found iridium anomalies at the base of all cap carbonates both after
the Marinoan and Sturtian glaciations; iridium and other platinum-group elements are typical
proxies for extraterrestrial (including exosolar) materials and are much more abundant than in
the Earth’s upper mantle and crust. These authors interpreted the anomalies to be the product of
the rapid accumulation of extraterrestrial material once trapped in the surface ice and later
transported to the ocean floor via the melting of the ice at the end of the glaciation.
Nevertheless, the excursion of iridium may also reflect the enhanced flux of extraterrestrial
material due to an encounter with a nebula.
Moreover, 244Pu is expected to remain in the Fe/Mn crusts of interest. Fields et al. (2005)
estimated the 244Pu production by a supernova explosion to approximately 0.9 ×10-7
solar
masses. The expected flux of the 244Pu at the Earth is approximately 10-16 kg m-2
yr-1
. A
significant amount (0.1 Bq m-2
) of the accreted 244Pu remains in the sedimentary rocks, even
considering the half-life of 244Pu (80 Myr).
The existence of abundant 100-μm spherical iron balls in pelagic sediments is also possible
direct evidence. For example, Miono et al. (1993) argued that the spherules accumulate in
Paleozoic-Mesozoic bedded cherts. These spherules are generally believed to originate from
25
micro-meteorites. The nebula winter model can be tested by similar but further advanced
investigations, including the analysis of the abundance of the isotopes and platinum family
elements of the minerals separated from spherules in the pelagic sediments, detailing their
exosolar nature. In addition, mineralogical investigations on the ages, the abundances of
platinum family elements, and the isotope ratios of the minerals of the exosolar grains in the
pelagic sediments at that time, will clarify the influence of the galactic environment on the
natural history of the Earth.

The theory is supported by time correlation, which is fairly close to starburts, which occur every 100Ma.

Specific evidence of historical astronomical events require the presence of supernovae elements, i.e. Iridium, in rocks from snowball times.

Other reasons for the Cambrian explosion are the edvent of bilateral animals, 600Ma, the last snowball event from 630Ma, PH and oxygen instability in the ocean, algea blooms. I found this pic which gives an idea of the oxygen concentrations from the cambrian: [![enter image description here](https://i.sstatic.net/tB1TL.jpg)](https://i.sstatic.net/tB1TL.jpg)

> **Comments:**
> **username_5**: What is the source of these plots? What are the error bars?  
> **username_3**: Downvoted for a complete lack of references.  
> **username_3**: The first graph looks a bit suspect. The very deep Marinoan glaciation is typically included in the Cryogenian (look at the name) rather than in the Ediacarian.  
> **username_4**: https://www.sciencedirect.com/science/article/pii/S1342937X13001597  and http://www.luckysci.com/2014/06/did-a-starburst-cause-earth-to-get-buried-in-kilometers-of-snow/  
> **username_4**: reference added.  
> **username_0**: https://www.youtube.com/watch?v=nVWy0bB2bVk&t=405s  So its possible for it to cause a mass extinction, but simultaneously not possible to cause mass mutations?  i think some troll is doing the downvoting.  
> **username_6**: https://astronomy.stackexchange.com/questions/27862/how-dark-would-the-sun-become-if-we-traversed-a-bok-globule Please delete at least the paragraph about Bok globules or provide references.  

---

