Other types of nebulae include emission nebulae, which are clouds of ionized gas emitting light of various colors; dark nebulae, which are clouds of gas so dense that background light is blocked; and protoplanetary nebulae, which occur when a star starts to shed its outer layers before becoming a planetary nebula.s it burns through its fuel, it will eventually collapse. The outer layers will be ejected in a shell of gas that will last a few tens of thousands of years before spreading into the vastness of space.
Dust fling up in the air will do harm to respiratory system, because of the conventional making method of chalk. The main ingredients are calcium carbonate or lime. now a new kind chalk, named Biaxi, absolutely finishes the dust, and is welcomed by teachers and students in China.
Mix 1/3 cup of plaster of Paris and 1/3 cup of cool water; stir until completely smooth. Mix that with 1 cup of latex paint and stir thoroughly. This will make enough chalk-finish paint for one coat on a six-drawer dresser.Chalk-finish paint should not be stored and reused.ix 5 tablespoons of plaster of Paris and 5 tablespoons of water with 1/2-cup of paint. Contrasting Colors. To paint this dresser, we used chalk-finish paint made from City Chic to give the entire piece one coat.