This iQuest has been created to take you on a journey that allows you to discover how water, the single most important ingredient for life as we know it, moves through Earth’s systems. We will also learn how NASA is able to follow the water as it moves in and out of its three phases during its travels, and why this is vital to our existence.

Let’s start by reviewing a little information about water. Use your background knowledge to answer these questions on your capture sheet:

• What exactly is water?
• How is water made?
• How did Earth gets its water in the first place? 

The answer to these questions can be found in the article, “Water’s Family Tree: Where Did it Come From” at http://go.nasa.gov/1jyN4io. Read this article, and use the information to answer the questions on your capture sheet. 

Earth is sometimes referred to as “The Water Planet”.

• Why do you think it has gotten that nickname?
• About how much of Earth’s surface do you think is covered by water?
• How much of Earth’s water is freshwater?

Watch the short animation called “Show Me the Water” (2:00) at http://go.nasa.gov/1A0pWw6​ and use the information to answer the questions on your capture sheet.  As you can see, we depend on freshwater resources to meet our needs in a great many ways. Read the article called “Precious Freshness: Water, the Way We Like It” at http://go.nasa.gov/15r8p6j and use that information to answer the questions on your capture sheet.

Have you ever thought about where the freshwater that comes out of your sink comes from? If you thought it comes from the water cycle, you are correct. Here is a quick refresher on Earth’s water cycle: http://go.nasa.gov/1pc6S8n.  NASA is helping scientists learn more about our water cycle as only NASA can- from space! As you watch “The Water Cycle: featuring Molecule Man” (4:56) at http://go.nasa.gov/1ppsYFU, fill in the data sheet on your capture sheet.

NASA has many satellites that are in orbit around Earth, studying various aspects of our water cycle. In this IQuest, we will take a closer look at four of these Earth-observing missions. We will begin with Terra-  - go to http://terra.nasa.gov/science/water-energy-cycle - and use the information you find on Terra to complete the data table column about Terra on your capture sheet.  The second mission is Aquarius/SAC-D, and the information can be found here: http://bit.ly/1viBngo.  Information on the third satellite, TRMM, can be found at: http://pmm.nasa.gov/TRMM. The final mission we will add to the data table is GRACE, and the information can be found at http://go.nasa.gov/1OvZiWd.

In the next iQuest, we will begin to look at data from these missions.