Sandpaper is typically made from silicate, with different impurities added depending on the hardness or coarseness of the sandpaper.
Hardened glass, however, is of a similar hardness to the silicate used in sandpaper and therefore can be scratched.
In some such formations, it would also react with local silicate minerals to form carbonates and bicarbonates that could stay put for millions of years.
The plates themselves are made of titanium silicate glass, an extremely strong material, and covered with low-friction diamond coatings which act as a lubricant.
Splitting the reflected sunlight from Mathilde into its component colours suggests that, along with silicate minerals such as pyroxine, she contains a lot of graphite and tar-like organic molecules.
In that event, a spacecraft would surely be scrambled to nudge the rock back into a harmless orbit.Secondly, the fly-by will help scientists determine if 2012 DA14 is made of dry silicate rock, like most asteroids, or of something more interesting, such as minerals that might be mined for water and rocket fuel.
On March 12th, Sean Hsu of the University of Colorado and his colleagues published a paper in Nature analysing tiny silicate grains spewed out by the plumes.
This substance (an iron-magnesium silicate whose greenish colour is reminiscent of olives) weathers rapidly in the presence of water.
Instead, they concentrated on serpentine, a substance rich in magnesium silicate which was found to cling efficiently to the internal surfaces of all common petrol and diesel engines.The problem was how to crush this mineral into small enough particles on an industrial scale.
It is composed of what sounds like a bizarre mixture: fly-ash, a fine-grained waste product from coal-fired power stations; carbon nanotubes, cylindrical molecules made of elemental carbon; and two binding agents, sodium silicate and sodium hydroxide.
Dr Schiraldi's approach does this by using a silicate clay called sodium montmorillonite as a skeleton that holds the plastic together.Sodium montmorillonite can be freeze-dried into a spongelike material known as an aerogel.
