Strange Asteroids Baffle Scientists

Raver32 writes to mention that two nearby asteroids may be evidence of a new class of asteroid or long eroded mini-world. Mineral evidence gathered using photometric data shows these asteroids to contain basalt not normally found in asteroid belt objects. "The lack of basalt and another mineral, olivine, in asteroid belt objects has long puzzled scientists. These two minerals would have formed the crust and mantle, respectively, of belt objects the size of Vesta or larger; theory predicts that more than half of all asteroids should be composed of one or the other of these substances"

Comments

Re:interesting

[Anonymous Coward]

Just Googled Vesta, for instance, and at 525 km, it's pretty big for a projectile thrown clear from an impact:

the object that smashed into Earth to produce the moon was roughly the size of Mars, that kind of thing is plenty big a collision to make Vesta.

Re:Wish more people would fess up their bafflement

[EL_mal0]

what the parent is lauding is *admitting* when you're stumped.

And trying to unstump yourself is the next necessary step. That's the critical part of scientific progress.

wtf?

[sensei moreh]

From TFA:

The asteroids, (7472) Kumakiri and (10537) 1991 RY16, were found to contain basalt, a grey-black mineral Basalt is a rock, not a mineral!

Re:wtf?

[finarfinjge]

Huh? Did you read the link you posted? The op is entirely correct. Basalt is NOT a mineral.

A mineral is a naturally occurring homogeneous solid with a definite (but generally not fixed) chemical composition and an ordered atomic arrangement. Basalt is comprised of labradorite feldspar (a mineral), augite (a mineral), hypersthene (a mineral), olivine (a mineral) with minor biotite, magnetite, spinel, ilmenite and horneblende (all minerals). It is distinguished from gabbro (a rock) by being much finer grained. (From Manual of Mineralogy (after James D. Dana), 19th edition, Cornelius S. Hurlbut, jr.).

Basalt is NOT a mineral. It is made up of minerals, but it is NOT a mineral.

Cheers.

JE

Re:interesting

[MBGMorden]

Good ol' Theia :). IIRC, the Science Channel will be showing "What if we had no Moon" on the 28th (next Tuesday). I'm I'm remembering correctly this does a great explanation of the Giant Impact Theory (though the impactor is referred to as Orpheus on the show - both Theia and Orpheus are two different names used for the same thing, though Theia is a little more common).