SMAP OVERLOAD

SMAP-- Soil Moisture Active Passive-- is a NASA program whose story dates back to the early 2000's. The origins of SMAP stemmed from analog style land research. Tired of surveying on foot, scientists sought to formulate other options for their teams. A plane radiometer that collected aerial footage proved to be an effective tool for conducting water content data collection and analysis. A global space mission program known as Hydros  went into development in years to come. In a 2007 Decadal Survey, NASA's SMAP was granted mission funding by the National Academy for the 2010-2020 top ten projects. The program went into research, design, and lot of testing with the hopes of launching November of this year.

Erika Podest, a land flux and ecosystem scientist at JPL talked to us about her work with water and carbon cycles in northern wetlands. SMAP measures the top 5 cm of surface soil moisture and determines its frozen or thawed state. With this data Podest is able to to collect information for application in weather forecasting, plant growth and runoff data. The water cycle-- evaporation, condensation and precipitation-- is what determines the weather, which is always changing. The signals will accumulate information on different types of soil and humidity modulations that affect crop yield and agricultural production. Furthermore, the data will aid in flood, drought and hurricane forecast. SMAP will enable her to compile her research seasonal solid and liquid changes of state in northern high latitude regions more efficiently. With that, she can better understand the timeline of carbon content in the atmosphere in order to determine the viability of local vegetation. The mission vehicle has two main functional tools: a radar and a radiometer. The former measures the overall radiation emitting from earth. The latter actively sends and receives soil sensitive signals. In three days, the entire globe soil moisture content is collected. The signals fall under microwaves on the electromagnetic spectrum-- this enables them to pass through clouds, reaching up to 36 km at a time.

Throughout the entirety of SMAP's design process, form follows function. It utilizes a rocket for launch which emits carbon and noise into Earth's atmosphere. It also serves as an observatory-- a robit with the ability to take measurements and relay them back to Earth, where it is processed and archived. Designers must emphasize the need for a compact craft that is both lightweight and cost-effective. Furthermore, team members must consider the need to use materials in an out-of-the-box manner-- applying thermal reflection paint onto the radars exterior in order to protect the amplifier and RF deck from overheating, for example. One component of the mission's structure that intrigued me was the antenna's parabolic surface is able to focus the RF signal wavelengths. The parabola-- a bell like shape-- has been used in physics, art, geometry and even by the military to focus sound, heat, and light waves.  SMAP is able to implement telecom features through the parabola's structure that acts like a mirror for ultrasound-like rays to be targeted. SMAP's antennae is able to collect high resolution feedback with it's radar component and radiation emission information that is of the highest accuracy.