There is possibly 2 stars in our solar system

[peacewithoutgod]

Seriously?  Dinosaurs were 66 million years ago, not 70 thousand ;-(

Damn, I knew that!

Maybe there was another comet strike of slightly lesser global around 70,000? I thought I read something on that, but it was so long ago, and time muddles everything!

[Unbeliever]

It's interesting that 70,000 years ago is about when a population bottleneck happened, but that was apparently the result of volcanic activity, when Toba exploded.

[Gerard]

It's interesting that 70,000 years ago is about when a population bottleneck happened, but that was apparently the result of volcanic activity, when Toba exploded.

Yes. And the Oort cloud is somewhat further away from us than Toba.

Gerard

[Baruch]

Damn, I knew that!

Maybe there was another comet strike of slightly lesser global around 70,000? I thought I read something on that, but it was so long ago, and time muddles everything!

Comets and asteroids frequently go on strike, they are more Left than the machinist union ;-)

[Baruch]

Yes. And the Oort cloud is somewhat further away from us than Toba.

Gerard

If a neutron star had struck the Earth, we wouldn't be talking about it.  If it came within the Solar System close enough to Earth, it might have stressed tectonic plates.  If it went thru the Oort cloud, it could have dislodged a bunch of comets.  It's a small solar system after all, it's a small solar system after all ...

[SGOS]

Damn, I knew that!

Don't feel bad, I read it the same way.  I keyed in on dinosaurs/70,000, and thought it sounded in the ball park.

[trdsf]

I was going to suggest Barringer Crater (aka Meteor Crater) in Arizona as being the impact event, but that was "only" 50,000 years ago.  Close, but no cigar, and it was small enough that its environmental impact was regional -- the 'kill zone' was less than 15 miles in radius:



I can't find any known or suspected impacts dated to 70-75Kyears ago to coincide with the Toba eruption, so it looks like space was innocent of that one.

[Baruch]

I was going to suggest Barringer Crater (aka Meteor Crater) in Arizona as being the impact event, but that was "only" 50,000 years ago.  Close, but no cigar, and it was small enough that its environmental impact was regional -- the 'kill zone' was less than 15 miles in radius:



I can't find any known or suspected impacts dated to 70-75Kyears ago to coincide with the Toba eruption, so it looks like space was innocent of that one.

No ... no ... a dwarf star impact or neutron star impact would be big enough that a volcanic eruption would be tiny.  I am talking about crustal distortion due to strong gravitational fields ... and obviously when such a monster would be well within the inner solar system temporarily not while in the Oort Cloud.

[trdsf]

If there were a massive object in orbit around the sun, its presence would be already known from the distortion it would induce on the orbits of the other planets.  Considering that the precession of Mercury's perihelion was known long before Einstein (whose General Relativity explained it) and that the movement measured was 0.16° per century, the presence of another massive object in the solar system -- even at the range of the Oort cloud -- cannot remain hidden.

Had a 'rogue' massive object transiting the solar system some 75Kyears ago or so, that also has a few problems.  First, if it's massive enough to have a serious gravitational impact, we should see higher eccentricities at least in objects that are Earth-crossing, especially the Moon.  Second, if it were small enough to not have an observed gravitational impact on other planets and the Moon, then it's unlikely it would have one on the Earth.  Certainly if something passed close enough to tidally stress the crust of the Earth, there should also be recognizable damage to the Moon.

I don't think there's any need to call on any outside forces to explain the Toba eruption.  Large-scale volcanic events happen on a planet with an active geology, especially when your clock is on geological time.