Long Equatorial Grooves on Vesta

[dougettinger]

The subject grooves appear to be fairly new with little disturbance of meteor strikes. The grooves then may have occurred close to the time of the major recent impacts at the south pole of 1 and 2 bya.

A possible idea is that the energy of impact created a very molten, but intact interior core. The impact also caused both a tilt and and a spin. The spin in turn created both centripetal forces and unequal shear forces of the original crust. Some of this thinner crust which was originally at the poles began to shear and create large latitudinal cracks that eventually filled in to finally create the rounded bottom grooves.

Does anybody have any collaborating or additional thoughts?

Colliding some thinking,
Doug

[dougettinger]

Or perhaps these equatorial grooves were created by a very slow collision between two bodies. Their surfaces crumpled where they came together and eventually filled in with regolith materials to create the rounded grooves.

Have NASA scientists developed an postulations yet?

Doug

[bystander]

http://asterisk.apod.com/viewtopic.php?p=184575#p184575

[dougettinger]

http://asterisk.apod.com/viewtopic.php?p=184575#p184575

I have reviewed the referenced articles that have tried to explain these strange grooves. One article explains that a large collision could have created the asteroid's troughs. The article further explains: "The crustal layer at the surface appeared to stretch to the breaking point and large portions of the crust dropped down along two faults on either side of the downward moving blocks, leaving the giant troughs we see today."

I do not understand how a large collision stretches the crustal layer to the breaking point. Can anyone in the forum explain what NASA meant in more graphic terms. Thanks.

Doug