Bentonite, the name given to a group of industrially useful clays containing the mineral montmorillonite. Bentonite clays are primarily aluminum silicates, mixed with varying amounts of sodium, calcium, or magnesium. A major use of bentonite clays is in oil-well drilling mud, a mixture of water, bentonite, and chemicals used to cool the drilling bit and carry away cuttings from the well. Certain types of bentonite expand to several times their original volume when mixed with water; they are used as sealants in dams and concrete-lined canals.
Nebulae are collections of dust and gases scattered across the galaxy. They're the sites where stars are born and what's left behind after they die.
Albert Einstein was a pretty smart guy. When you look up the word "genius" in the dictionary, so the saying goes, it's a pretty safe bet you'll see Einstein's mug. Think you’re smart enough to take on a quiz about the famed thinker?