The Great Dying

[Fallingstar1971]

Could Fomalhauts ignition have had a contributing factor to the Great Dying seeing as its only 25 lys away?


Star

 

[origin]

I assume you mean the extinction event that occurred ~65 million years ago. I would think not for 2 reasons. The first is that it is estimated that the star 'turned on' 100 to 200 million years ago. The other reason is that the ignition of a star is not that energitic. I wouldn't want to be in the neigborhood(!) but at 25 ly it should not have a very profound effect.

 

[Fallingstar1971]

No.

The Great Dying ci. 250 my ago. 99% of all life was destroyed and that layer of black stuff went down where it is marked in the fossil records.

The 250 mya is what caught my eye when I was reading about Fomalhaut.

But if the rest of what you say is true, then it probably doesn't matter anyway

Star

 

[origin]

No.

The Great Dying ci. 250 my ago. 99% of all life was destroyed and that layer of black stuff went down where it is marked in the fossil records.

The 250 mya is what caught my eye when I was reading about Fomalhaut.

But if the rest of what you say is true, then it probably doesn't matter anyway

Star

Ah, the prelude to the dinosaur age...

 

[3488]

Hi Fallingstar1971.

Very interesting & inteliigent question.

I would like to contribute something here.

The short answer is no.

But let me explain.

Fomalhaut quick facts.
Fomalhaut is at most 200 million years old (0.2 GYO, Sun 4.6 GYO), so the age is just less than the time since The Great Dying. Fomalhaut is approx 2.1 times the Sun's mass, 18 times more luminous than our Sun & is approx 1.8 times the Sun's diameter. Fomalhaut's is an A3 star yielding a 'surface' temperature of 8,300 Celsius, our Sun is a G2 star yielding a 'surface' temperature of 5,500 Celsius. Fomaulhaut rotates on it's axis once every 1 day & 2 hours (equatorial, like our Sun probably has differential rotation, the polar regions being slower) as against our Sun's 25 days 8 hours (equatorial).

Fomalhaut is thought to be part of the Castor moving group, which includes Castor (obviously & AKA Alpha Geminorum), Vega (Alpha Lyrae), Alderamin (Alpha Cephei), Zubenelgenubi (Alpha Librae), Zeta Leporis (central star of a gigantic asteroid belt), & Psi Velorum amongst other lesser known stars.

All of these stars are thought to have formed together within a volume of only a few light years of one another in the same nebula, then for several million years were part of the same open cluster (like the Pleiades M45), then since have scattered, but still share the same general orbit around the centre of the Milky Way.

Regarding the ignition of Fomalhaut & The Great Dying. Certainly not.

1). Fomalhaut is in a different orbit around the centre of the Milky Way than our Sun & is currently receding at approx 6.3 KM per second. Closest approach to our solar system has already occured.

2). 250 million years ago, Fomalhaut was only a protostar at best.

3). 250 million years ago, Fomalhaut would have been in a very different part of the Milky Way, much further away, possibly several 1,000s of light years away.

4). The Great Dying was almost certainly entirely of the Earth's own making. Enormous continent Pangea formed, creating a gigantic hot desert in it's interior. Increased global temperatures resulted from this, this alone would have lead to the extinction of most land dwelling species, & chemical reactions in the oceans lead to lower PH levels (increased acidity) killing off most marine life. There was also increased volcanism during this period, leading to increased toxicity in the atmosphere.

The KT extinction 65 MYA, was certainly two fold, comet impact & mass volcanism together.

Andrew Brown.

 

[origin]

Thanks Andrew for a very informative post!

It is funny that I thought of Fomalhaut as being in the same proximity to earth now as it was 200 million years ago. Probably in my subconscious I think of the stars as unmoving when of course nothing is stationary.

 

[3488]

You are very welcome origin.

Over time the constellations to change, star brightness alter over time as they approach / recede from the solar system.

Approx 1 million years ago, Saiph (Kappa Orionis) was the brightest star, at approx magnitude -4.5 or about the same as Venus. Now Saiph is magnitude +2.

Approx 500,000 years ago, Mirzam (Beta Canis Majoris) was the brightest star, approx -2.7 or about the same as Jupiter. Now is at magnitude +1.95.

440,000 years ago, Capella was mag -1.8 & Aldebaran -1.1, both were within ONE degree of the Earth's north celestial pole.

Approx 500,000 years ago, Arcturus attained naked eye visibility as it moved within range, in just 4,000 years time will make the closest approach to our Solar System, & in approx 500,000 years time will have moved beyond naked eye range.

In approx 250,000 years, Menkalinan (Beta Aurigae) will blaze at approx mag -2.7, or approx the same as Jupiter. In 1.5 million years Eltanin (Gamma Draconis) will be the brightest star in Earth's skies at approx magnitude -1.7.

Andrew Brown.

 

[Fallingstar1971]

I have to agree, I find myself thinking about the stars as "fixed" even though in the back of my mind I know that the whole galaxy makes one spin per 250 million years as well. That should have been a tip off.

Its just amazing how fast these objects are moving in order to cover these distances, yet to us, they give the illusion of never changing. It all comes down to scale, I suppose. The milky way doesn't have many more spins yet before it collides with Andromeda.

Anyway, thank you for the information. I now realize that there is a lot more to take into consideration when thinking about these past events. Currently, we seem to have a very big puzzle, and you helped me see how a piece just didn't fit quite correctly. Thank you.


Star

 

[a_lost_packet_]

Hi Fallingstar1971.

Very interesting & inteliigent question.

I would like to contribute something here.

The short answer is no.

But let me explain.
...

Andrew Brown.

Excellent post!

 

[jasonpply]

is anyone else considering the fact as mentioned before......... the galactic rotation of our star around the milky way is 250 million years. and the dinosaurs went exticnt 250 million years ago. coincedence? are we on our way out tooo. maybe it was i part due to our position in the disk plane of the milky way????

 

[3488]

Hi jasonpply,

No that is wrong. The Dinosaurs became extinct 65 million years ago.

The Great Dying is another, even greater catastrophic mass dying approx 250 million years ago. The two are not related.

It is a coincidence for sure that the Solar System's orbit period around the Milky Way's centre of 225 million years is very close to the Milky Way's rotation of 250 million years, however, this is not enough to link The Great Dying, with our Solar System's orbital period around the galactic centre.

The Great Dying was almost certainly due to events following the formation of the giant continent Pangea.

Andrew Brown.

 

[3488]

Thanks A-L-P. Much appreciated. I love this sort of thing. Fascinating stuff. :mrgreen:

Andrew Brown.