• New map shows saltiness of Earth’s oceans

    A NASA-built instrument aboard an international satellite has made its first global map of the saltiness of Earth’s seas, just three months after the high-tech sensor rocketed into orbit.On the colorful map, yellow and red represent areas of higher salinity (or salt

  • 2011 Skywatching Guide: Planets in the Solar System

    The planets of our solar system are at tomes some of the most rewarding and simplest skywatching targets to spot, if you know when and where to look. Here's a look at how to observe the planets of the solar system in 2011: Tip: Astronomers measure distances in…