Bats
"Blind as a bat" is a common expression. It is true that bats don't use thei...
The U-2 is an old spy plane. It used to fly over the former Soviet Union. Now, the plane has a new name and a new mission. NASA calls the plane ER-2. Its new mission is to help spot toxic waste. A special instrument is on board the ER-2. It is called an imaging spectrometer. It measures wavelengths, or spectrums, of light. All materials absorb and reflect light differently. In other words, they have their own "spectral fingerprint." The spectrometer gives scientists the data they need to identify minerals. Scientists then make maps. They focus on areas near old mines. These areas are sources of pollution. The areas harm rivers and streams. Scientists use colors to show locations of different minerals. They look for high concentrations of dangerous minerals. The maps are very helpful. They pinpoint the exact location of toxic areas. They make clean up efforts easier and less expensive.
Every fall, the leaves on some trees turn different colors. Leaves are green in the spring...
Salt is everywhere. It is in restaurants and kitchens. Little packets of salt come with fa...