[acsinuk (OP)]

Grand Canyon Formation  a Coronation Revelation
Just visited the south side and was amazed to see the layers of our planet’s historic topology staring at me.  See pictures courtesy of US national parks.    https://www.nps.gov/grca/learn/nature/grca-geology.htm 
Geologists believe that this 250 km long 25 km wide canyon was formed around 2 to 4 million years ago but cannot explain how.  Well, neither could I as if a huge asteroid collided with earth in the east west direction then the crater would be huge with smashed out rocky matter blasted forward of which there is no evidence.
But if the asteroid was made of positron enclosed anti-matter then what we see makes sense as a 25 km wide chunk of anti-matter coming in at a low angle would hit the surface of the planet and bouncing slightly as it moved forward leaving a ragged path as it annihilated kilogram for kilogram of planetary electron enclosed matter magnoflux stuff could leave behind a canyon deep enough to expose the earth’s mantle that formed over 2 thousand million years ago.
Asteroids can attain velocities of 50 km/second which means the Grand Canyon could have been formed in just 5 seconds but the annihilation of the adjacent atmosphere would have certainly sucked all trees and vegetation out of the ground tens of kilometres around the site and the Colorado river later forced to find a new way inside the canyon.
If the asteroid were a 25 km cube then around 5x10^14 tons of planetary matter would have been annihilated resulting in what we see now.

[Origin]

    I certainly hope this is a bad joke!

canyon was formed around 2 to 4 million years ago but cannot explain how.

Wrong and wrong.

Give it up while your behind...

[Zer0]

How would an Anti-matter asteroid reach & impact the Earth's surface?

What about the Matter particles in the Earth's atmosphere?


@OP
I have a Query as well.
Do Photons interact with Positrons?
If so, what is the observed effect or end result?

[Kryptid]

An antimatter asteroid would explode as soon as it touched the atmosphere.

Do Photons interact with Positrons?

Yes, but it's pretty much the same as photons interacting with electrons. Nothing special really happens.

[alancalverd]

A bouncing antimatter asteroid would leave a series of large deep lakes joined by shallow streams. Not like the Grand Canyon. Nor is there evidence of mantle material upwelling into the slot. Every other canyon in the world seems to have been made by a river - what's so special about this one?

The final program in the Archaeological Apocalypse series (Netlfix, Prime or Channel 5 - I can't remember which) concerns a much more interesting and credible hypothesis about an apparent "shock" canyon in Wyoming which almost certainly wasn't formed by slow erosion.

[Origin]

Asteroids can attain velocities of 50 km/second which means the Grand Canyon could have been formed in just 5 seconds but the annihilation of the adjacent atmosphere would have certainly sucked all trees and vegetation out of the ground tens of kilometres around the site and the Colorado river later forced to find a new way inside the canyon.
If the asteroid were a 25 km cube then around 5x10^14 tons of planetary matter would have been annihilated resulting in what we see now.

Ignoring the kinetic energy aspect, the energy release from that much antimatter annihilating with matter would be about 4 x 10^19 megatons of TNT or the total energy of the output of the sun for several hundred days.  All life would be eradicated and a good portion of the earth would be blown out into space.  So I think your idea needs some tweaking. 

[Bored chemist]

It's interesting to see the layers of rocks in places like the Grand Canyon.
A matter/ antimatter explosion would have destroyed that structure.
A gentle process like running water will cut through the layers, leaving the strata visible.

The OP needs to check the credibility of sources better.

[acsinuk (OP)]

Space .com have queried this post as they consider huge energy would be released.
I have referred them to review the Tunguska event.
Please consider what happened in the Tunguska event but notice that no crater or burning rocks were ever reported the material just simply vanished. Impossible!!
If it was an anti-matter meteors that hit us this would immediately annihilate the atmospheric gases and cause a huge vacuum that of course causes an air blast that destroys forests and dwellings by sucking then out of the ground as in the case of the Tunguska event but there was no evidence of scorched trees so little or no energy creation.

Further, where is the meteorite matter gone? Simply vanished impossible; no it was annihilated kg for kg by our atmospheric gases.

[Bored chemist]

Please consider what happened in the Tunguska event

OK.
We will consider a meteor strike.
Do you not understand that an antimatter collision would have eft the area intensely radioactive?
There is absolutely not way it is possible for Tunguska to have been caused by antimatter.
So why are you mentioning it on a science page?

Further, where is the meteorite matter gone?

Vapourised and distributed round the world by atmospheric currents of course.

[Bored chemist]

If it was an anti-matter meteors that hit us this would immediately annihilate the atmospheric gases and cause a huge vacuum

Yes and no.
Any explosion creates a rarefaction wave.
The atom bombs worked by annihilating matter.
Do you think they sucked stuff in, or do you realise that the explosion pushed stuff out?

[Origin]

Please consider what happened in the Tunguska event but notice that no crater or burning rocks were ever reported the material just simply vanished. Impossible!!

Perhaps you should review the Tunguska event since you seem to not understand what happened there.  You should go to a reputable site instead of a pseudoscience site, where it seem to have gotten your confused ideas.

[Bored chemist]

A bouncing antimatter asteroid would leave a series of large deep lakes joined by shallow streams.

I don't know if this song is well known among out transatlantic cousins
https://en.wikipedia.org/wiki/Ten_Green_Bottles
I gather they have a comparable "99 bottles of beer on the wall"

Wiki points out that there are other versions; some vulgar.

One such (stripped of vulgar language) runs as follows

Ten sticks of dynamite hanging on the wall
Ten sticks of dynamite hanging on the wall
And if one stick of dynamite should accidentally fall
There?d be no sticks of dynamite and no [expletive] wall

Technically, it's wrong. Dynamite is difficult to initiate and dropping from any sensible wall wouldn't initiate an explosion.

But I was reminded of it by the idea that a bouncing antimatter asteroid would leave lakes and streams rather than
"No bouncing asteroid and no [expletive] planet."

[alancalverd]

Tunguska was probably an air burst of a stony meteorite at 5 km altitude or more. This would produce a "down and out" blast that flattened trees but did not scorch them. Unlike an iron meteorite, any remnant of the projectile would be pretty indistinguishable from the surface soil.

A low-level nuclear explosion produces an initial outward shockwave but the characteristic mushroom cloud is an "in and up" convection cell that slurps debris from the ground and distributes it at high altitude.

The damage from both is essentially of circular symmetry. The Grand Canyon is a wiggly line about 250 miles long and no more than 20 miles wide.

[acsinuk (OP)]

Thanks Alan,
The shape of the antimatter meteor must have been in a horseshoe or boomerang shape.  It will be rotating of course as the earths magnetic field would make it spin sideways while moving forwards.

The atom bomb blasted out but the antimatter annihilation would have sucked in only; nothing would go up and be scattered about.

[Origin]

The shape of the antimatter meteor must have been in a horseshoe or boomerang shape.  It will be rotating of course as the earths magnetic field would make it spin sideways while moving forwards.

The atom bomb blasted out but the antimatter annihilation would have sucked in only; nothing would go up and be scattered about.

The simpler and more logical conclusion is that the grand canyon was made from erosion. 

Also a meteor made from antimatter would not rotate from the earths magnetic field.  The magnetic field would effect an antimatter meteor the same as it would a matter meteor.

[Bored chemist]

The atom bomb blasted out but the antimatter annihilation would have sucked in only;

Still wrong.
Repeating a false statement doesn't make it less wrong.

The simplest form of annihilation causes the creation of two gamma rays.
Gamma rays carry momentum.
They will spread out and they will push on teh air or whatever around them.
So there will be an explosion.
They also carry energy and that would be degraded to heat. So the air locally would be heated a lot and suddenly.
So it would expand violently.
It would be an explosion- just like a conventional nuke, but about a thousand times more potent.
This is true no matter how dearly you wish to believe that you know more than science does.

And you still haven't answered my  point about the radioactivity.

And you still haven't explained why the reaction  - which would create temperatures of billions of degrees and a blast to match- somehow didn't destroy features that are made of loose sand stuck together with a bit of dirt.

Your claim is like saying someone did reconstructive brain surgery using dynamite.

[paul cotter]

The matter/antimatter reaction would be the most violent of all possible explosive reactions by at least two orders of magnitude on a per weight basis.

[acsinuk (OP)]

"Also a meteor made from antimatter would not rotate from the earths magnetic field.  The magnetic field would effect an antimatter meteor the same as it would a matter meteor"
No, antimatter would spin backwards in a steady magnetic field and thus the antimatter magnoflux inertia energy stuff would annihilate the matter stuff kg for kg. 
Planetary matter stuff is made up of electromagnetic massless stuff contained in electron shells which allow it to slow down to become touchable negative material.

[The Spoon]

"Also a meteor made from antimatter would not rotate from the earths magnetic field.  The magnetic field would effect an antimatter meteor the same as it would a matter meteor"
No, antimatter would spin backwards in a steady magnetic field and thus the antimatter magnoflux inertia energy stuff would annihilate the matter stuff kg for kg. 
Planetary matter stuff is made up of electromagnetic massless stuff contained in electron shells which allow it to slow down to become touchable negative material.

How to demonstrate that you have complete ignorance of geomorphological processes without explicitly stating it. Likewise, scientific method.

[Bored chemist]

No, antimatter would spin backwards in a steady magnetic field

No it would not.
No more than normal matter spins "forwards".
That's just silly.

Planetary matter stuff is made up of electromagnetic massless stuff contained in electron shells which allow it to slow down to become touchable negative material.

That's nonsense.