Interstellar Asteroid Impacts and Ring Dike Complexes

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The lack of high velocity impact models creates problems when arguing about interstellar asteroids. Long period comets from this Solar System might have enough energy to produce these effects.

I guessed that only interstellar asteroids would have enough velocity to cross the energy threshold.

Every model that I have seen has either been an airburst or an impact at about 20 kms. The absence of higher velocity models appears intentional. Common sense argues that at some velocity asteroids would easily punch through the crust and enter the mantle.

Interstellar impacts are the invisible opposing argument that drives their deceptive public arguments (Anoxia).

Academic unicorns are often found in engineer’s meat lockers.

Impact plumes anchor structures into the mantle. With this deep anchor continents move over them or around them. I am putting this out there as a possible mechanism not as a fact.

It appears that in older plumes the magma production does not punch through the thin 10km oceanic crust. It appears to inflate and lift the oceanic crust. Some volcanoes do punch through creating an arc of islands visible on the surface.

In this illustration the South America and Antarctica plates are moving to the west. This is recognized for South America but Antarctic motion seems to be muddier.

It appears that the impact formed the South Sandwich Arc sometime in the last 40 million years. The South America and Antarctica plates appear to have split and moved around the impact plume anchor. The depth of the earthquakes in this location indicate an impact punching through the crust.

Plate tectonics began when Wegener and others noticed how continents fitted together. Sometimes the obvious solution is the correct one.

I lean toward an interstellar impact origin for this structure. Neat illustration.


"Science begets knowledge, opinion ignorance.
Whilst I appreciate the effort you put in to your posts, I am often overwhelmed. I don't believe that I am the only one here who appreciates the "softly, softly catchee monkey" approach. Acceptance a bit at a time.

"Common sense argues that at some velocity asteroids would easily punch through the crust and enter the mantle."
Sorry, my common sense is not common with your common sense unless you are talking extreme velocities. You could use this argument to say if you shot a bullet at the Sun with sufficiently high velocity, it would come out the other side and keep going. I would say you might be right unless that velocity would have to be faster than c. And I would say that the bullet would melt before it got into the photosphere.
That would be my common sense.
I retract the statement about common sense.

(Military technology) common sense if you know how kinetic anti-tank weapons work.

If I use kinetic energy as a baseline a 8.35 kilogram penetrator moving at 1750 meters per second has about 12.7 million joules of energy. This can penetrate 47 cm of steel armor.

A 100 kilogram projectile moving at 505 meters has the same energy.

The 100 kilogram projectile will give the crew one hell of a headache but it won’t penetrate the armor (big dent maybe a new paint job).

A material can change state (become vaporized) on impact yet its density can increase. The density of a uranium core is at least doubled during the implosion preceding the super critical chain reaction. An impact at 500kms will compress matter a lot more than any chemical implosion. If the mass penetrates the object, or comes to a complete stop within that object, the kinetic energy of the compressed matter converts to heat.

Because heat flow/diffusion is so slow temperatures of over a million degrees can result. Part of the heat (and compression) is transferred causing rock melting. A lot of energy is transferred into the vaporized impact plume which blasts material out of the gravity well.

Velocity is why interstellar asteroids are the best candidate for these impacts. Solar escape velocity at the distance of the Earth is somewhere in the 20-50 kms range. Asteroids in this system cannot hit Earth with velocities higher than this and remain gravitationally bound to the Sun. This velocity does not appear to be high enough to explain the deep impact structures found on the Earth.


"Science begets knowledge, opinion ignorance.
You obviously have a great deal of knowledge and are not prone to hoarding it, which is a good thing. However, all the detail about army missiles left me cold. After reading it, I thought 'that was impressive' but then I asked myself what the dickens it meant. Or, rather what was the relevance.

When I saw the last paragraph, I sighed with relief. 'At last a short succinct paragraph with a point', I thought. Then I came upon this: "Asteroids in this system cannot hit Earth with velocities higher than this and remain gravitationally bound to the Sun." If they hit Earth, which is surely what we are posting about, (Interstellar Asteroid Impacts and Ring Dike Complexes) how are they going to remain gravitationally bound to the Sun?

On a different point, have you seen "Our Solar System stole Asteroids from Interstellar Space" in All About Space just out?
Asteroids from our Solar System have a maximum velocity when they impact Earth. This velocity appears to be too low to create events like at the Scotia Arc.

Statistically it is much easier for an interstellar asteroid to impact than it is to be captured. An interstellar asteroid is moving with a relative velocity to the sun before it falls into the Sun’s gravity well. If it doesn’t run into anything, it will leave the Sun’s gravity well with the same velocity (but a different direction).

For an interstellar asteroid to be captured this relative velocity has to be removed/negated.

The simplest way to lose this velocity is for the interstellar asteroid to impact a small body and slow down enough to be captured.

Another way is for the interstellar asteroid to pass through the atmosphere of a planet or gas giant.

A third way is the reverse of a gravity slingshot. By sheer luck the interstellar asteroid passes by a planet at the correct orientation and at the right distance to lose velocity.

All of these processes are improbable so the presence of captured interstellar asteroids automatically argues that a lot of them had to have passed through the Solar System for these to be captured at all.

Direct impact could shatter an interstellar asteroid without slowing it down much. The atmospheric window to slow down an interstellar asteroid without it impacting is ridiculously small.

The opposite of the slingshot (gravity trampoline?) looks to be a very rare event. After capture it still has a short lifespan (impacting Jupiter or other bodies) since capture does not automatically mean going into a long term stable orbit.