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SMAP Large Antenna

SMAP Large Antenna

The large antenna that is shared by both radar and radiometer is SMAP’s most prominent feature. It operates just like a satellite dish, only is much larger, where a reflector collects all of the radio waves which focuses them into the feed horn. The feed horn collects the echoes from the radar and the surface emissions from the ground and sends them to the radar and radiometer electronics for processing. The feed horn is a large cone visible on the outside of the spacecraft. The antenna reflector is a mesh antenna 6 meters (about 20 feet) in diameter.

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Results of a study reveal that SMAP soil moisture retrievals are generally better than AMSR2 soil moisture data.

Soil moisture products acquired from passive satellite missions have been widely applied in environmental processes.

Validation Analysis of SMAP Products Using Ground-Based Measurements

NASA scientists are auditioning the radar aboard a European satellite to see how well it stands in for the radar that failed aboard the U.S. space agency’s newly launched Soil Moisture Active Passive (SMAP) satellite in July.

NASA scientists are auditioning the radar aboard a European satellite to see how well it stands in for the radar that broke down aboard the U.S. space agency’s newly launched Soil Moisture Active Passive (SMAP) satellite in July.

NASA Focused on Sentinel as Replacement for SMAP Radar

SMAP data provide another way to see flooding in South Carolina.

SMAP data provide another way to see flooding in South Carolina.

Devastating Carolina Floods Viewed by NASA's SMAP

SMAP’s radiometer, which measures temperatures on Earth’s surface, can do more than previously thought, and the spacecraft remains healthy, scientists say.

SMAP’s radiometer, which measures temperatures on Earth’s surface, can do more than previously thought, and the spacecraft remains healthy, scientists say.

Scientists Hopeful About SMAP After Loss of Radar

Discovery Channel features students exploring Mount Kilimanjaro. They will learn about collecting environmental data on the mountain’s six biomes and meet a NASA Jet Propulsion Laboratory scientist to discuss the SMAP Mission, a satellite that measures the Earth’s soil moisture.

Discovery Channel features students exploring Mount Kilimanjaro and learning about SMAP.

Students Learn About SMAP during Mount Kilimanjaro Expedition

Dara Entekhabi, the science team leader of NASA’s Soil Moisture Active Passive (SMAP) satellite, was selected by the American Geophysical Union (AGU) to receive the 2015 Hydrologic Sciences Award.

Dara Entekhabi, the science team leader of NASA’s Soil Moisture Active Passive (SMAP) satellite, was selected by the American Geophysical Union (AGU) to receive the 2015 Hydrologic Sciences Award.

Dara Entekhabi Is Recipient of 2015 Hydrologic Sciences Award

NASA's SMAP satellite observatory conducted a field experiment as part of its soil moisture data product validation program in southern Arizona.

NASA's SMAP (Soil Moisture Active Passive) satellite observatory conducted a field experiment as part of its soil moisture data product validation program in southern Arizona on Aug. 2-18, 2015.

SMAPVEX 15 Field Campaign Measures Soil Moisture Over Arizona

NASA scientists are on a mission to map global soil moisture, and through SciStarter, they’re teaming up with citizen scientists to gather valuable data from the ground to complement and validate what is seen from space.

Known as the Soil Moisture Active Passive (SMAP) satellite mission, the research will help scientists understand links among Earth’s water, energy and carbon cycles.

NASA and SciStarter Enlist Citizen Scientists to Examine Soil Moisture

News from the fourth Soil Moisture Active Passive (SMAPEx-4) field campaign, carried out in Yanco, NSW, Australia, from May 1-23, 2015. This field experiment is part of the CalVal activities for the NASA SMAP mission.

Notes from the Field

Notes from the Field

NASA-funded study finds that Texas’ historic rainfall and resulting soil moisture could strengthen a storm moving inland from the Gulf of Mexico.

NASA-funded study finds that Texas’ historic rainfall and resulting soil moisture could strengthen a storm moving inland from the Gulf of Mexico.

'Brown Ocean' Effect May Bedevil Soggy Texas as Storm Nears

An assessment of surface soil moisture is necessary for applications such as weather forecasting, climate change modeling, monitoring of agricultural productivity, water resources management, drought prediction, flood area mapping, and ecosystem health monitoring.

he SMAP observatory separated from the upper stage 57 minutes after liftoff, and solar arrays opened one minute after separation.

Mission to Monitor Soil Moisture with Active-Passive Remote Sensing

“We’re entering the golden age of satellite missions for water,” says Jay Famiglietti, NASA’s senior water scientist. His research team is mapping the dwindling water supply of the drought-gripped western United States.

“We’re entering the golden age of satellite missions for water,” says Jay Famiglietti, NASA’s senior water scientist.

California Has No Idea How Much Water It Has Left; NASA Can Help

SMAP’s measurements will help scientists to understand the circulation of water and carbon. The carbon cycle has more branches than the water cycle; it transfers from the air, in the form of carbon dioxide, to soil, rocks, surface water and frozen surfaces.

SMAP’s measurements will help scientists to understand the circulation of water and carbon.

SMAP Will Help Scientists Understand Circulation of Water and Carbon

With its antenna spinning at full speed, NASA's new Soil Moisture Active Passive (SMAP) observatory has successfully re-tested its science instruments and generated its first global maps, a key step to beginning routine science operations.

With its antenna spinning at full speed, NASA's new Soil Moisture Active Passive (SMAP) observatory has successfully re-tested its science instruments and generated its first global maps, a key step to beginning routine science operations.

NASA Soil Moisture Mission Produces First Global Maps

Kent Kellogg will be the featured speaker May 11 when the La Cañada Flintridge Coordinating Council holds its annual Les Tupper Awards ceremony in von Karman Auditorium at the Jet Propulsion Laboratory. The event begins at 7 p.m.

SMAP Manager to Join Tupper Awards

SMAP Manager to Join Tupper Awards

The 20-foot (6-meter) "golden lasso" reflector antenna atop NASA's new Soil Moisture Active Passive (SMAP) observatory is now ready to wrangle up high-resolution global soil moisture data.

SMAP's spinning antenna sweeps out a wide swath to map soil moisture.

It's 'full spin ahead' for soil moisture mapper

Mission controllers at NASA's Jet Propulsion Laboratory in Pasadena, California, have commanded the 20-foot (6-meter) reflector antenna on NASA's new Soil Moisture Active Passive (SMAP) observatory to begin spinning for the first time. The partial spin-up is a key step before science operations.

NASA's New Soil Moisture Mapper Goes for a Spin

NASA's New Soil Moisture Mapper Goes for a Spin

NASA's new Soil Moisture Active Passive (SMAP) observatory has successfully completed a two-day test of its science instruments. The observatory's radar and radiometer instruments were successfully operated for the first time.

NASA's Soil Moisture Mapper Takes First 'SMAPshots'

NASA's Soil Moisture Mapper Takes First 'SMAPshots'

Mission controllers at NASA's Jet Propulsion Laboratory in Pasadena, California, today sent commands to unfurl the massive 20-foot-wide (6-meter) reflector antenna on NASA's new Soil Moisture Active Passive (SMAP) observator. The deployment of the mesh reflector antenna, which supports the collection of SMAP's radar and radiometer instrument measurements in space, marks a key milestone in commissioning the satellite. S

SMAP Completes Key Milestone

SMAP Completes Key Milestone

Over the past 12 months NASA has added five missions to its orbiting Earth-observing fleet – the biggest one-year increase in more than a decade. NASA scientists will discuss early observations from the new missions and their current status during a media teleconference at 2 p.m. EST Thursday, Feb. 26.

NASA Briefing to Highlight Early Results from New Earth Science Missions

NASA Briefing to Highlight Early Results from New Earth Science Missions

NASA's SMAP has successfully separated from the Delta II rocket off the east coast of Africa, and engineers have successfully established communication with the spacecraft.

NASA Launches Groundbreaking Soil Moisture Mapper

NASA Launches Groundbreaking Soil Moisture Mapper

A United Launch Alliance Delta II rocket with the Soil Moisture Active Passive (SMAP) observatory onboard launches from Space Launch Complex 2, Saturday, Jan. 31, 2015, Vandenberg Air Force Base, Calif. S

We have liftoff!

We have liftoff!

NASA's Soil Moisture Active Passive mission (SMAP) now is scheduled to launch from Space Launch Complex 2 at Vandenberg Air Force Base, California at 6:20 a.m. PST (9:20 a.m. EST) Saturday, Jan. 31, on a United Launch Alliance Delta II rocket. NASA Television coverage of the launch will begin at 4 a.m. PST (7 a.m. EST).

Launch of NASA Soil Moisture Mapping Mission Set for Saturday

Launch of NASA Soil Moisture Mapping Mission Set for Saturday

This is a wonderful infographic brought to you by Space.com.

How NASA's Soil Moisture Satellite Works (Infographic)

How NASA's Soil Moisture Satellite Works (Infographic)

NASA's Soil Moisture Active Passive (SMAP) observatory is perched on the pad at Space Launch Complex 2 (SLC-2), and is set to launch Thursday, Jan. 29, at 6:20 a.m. PST (9:20 a.m. EST) from Vandenberg Air Force Base in California. A United Launch Alliance Delta II rocket will carry SMAP into orbit. The launch window lasts three minutes.

NASA's SMAP Earth Mission Awaits Launch

NASA's SMAP Earth Mission Awaits Launch

Precipitation and temperature are part of every weather forecast. Precipitation comes from clouds, clouds are formed of airborne water vapor, and vapor comes from evaporating soil moisture -- so soil moisture governs precipitation.

Building a Better Weather Forecast? SMAP May Help

Building a Better Weather Forecast? SMAP May Help

NASA doesn’t study just the stars and planets; it is also concerned with the soil beneath your feet. Studying the moisture in the top two inches of the soil from space with a satellite named "SMAP" can help weather forecasters predict flash floods, farmers grow more crops, and communities plan for drought.

NASA's Earth Minute: Dishing the DIrt

NASA's Earth Minute: Dishing the DIrt

NASA held a media briefing at 11 a.m. PST (2 p.m. EST) Thursday, Jan. 8, at NASA Headquarters in Washington to discuss the upcoming Soil Moisture Active Passive (SMAP) mission.

NASA Previews SMAP Launch

NASA Previews SMAP Launch

Scheduled for launch on Jan. 29, 2015, NASA's Soil Moisture Active Passive (SMAP) instrument will measure the moisture lodged in Earth's soils with an unprecedented accuracy and resolution. The instrument's three main parts are a radar, a radiometer and the largest rotating mesh antenna ever deployed in space.

SMAP Artist's Rendering of Instrument

Technology Innovations Spin NASA's SMAP into Space

SMAP will allow for improved weather forecasts that will upgrade predictions for heat stress and virus-spreading rates. In short, SMAP will allow policy makers to plan farther ahead into the future.

SMAP Artist's Rendering

New NASA satellite should help scientists better predict rain, drought

SMAP will be working with the Texas Soil Observation Network to help water managers in Texas.

How Underground Sensors In Texas Will Help NASA Predict Drought and Floods

How Underground Sensors In Texas Will Help NASA Predict Drought and Floods

NASA’s innovative soil moisture mapper, a new environmental satellite launching in January, has been fueled up for blastoff from Vandenberg Air Force Base in California.

Artist's Rendering of SMAP Instrument

Soil moisture mapper fueled for January launch

The Latest Images

Today's Map

Latest from SMAP

The launch of NASA’s Soil Moisture Active Passive (SMAP) observatory has been delayed to a targeted launch date of Jan. 31, pending completion of minor repairs to the United Launch Alliance Delta II launch vehicle.

SMAP Earth Mission Launch No Earlier than Saturday

SMAP Earth Mission Launch No Earlier than Saturday

Initial data from SMAP capture the 2015 spring thaw progression over the Northern Hemisphere, with a thaw front extending from predominantly non-frozen southern latitudes to the still-frozen north.

NASA SMAP Images Show Progression of Spring Thaw in Northern Hemisphere

NASA SMAP Images Show Progression of Spring Thaw in Northern Hemisphere

NASA celebrated the 45th annual Earth Day April 17-22 with a variety of live and online activities to engage the public in the Agency's mission to better understand and protect our home planet.

NASA Celebrates Earth Day with Public Events, Online Activities

NASA Celebrates Earth Day with Public Events, Online Activities

NASA's SMAP and University of Texas scientists are rounding up critical soil information for managing the Lone Star State's limited water.

NASA's SMAP and University of Texas scientists are rounding up critical soil information for managing the Lone Star State's limited water.

How Dry Is Texas? SMAP, TxSON Network Aim to Find Out

SMAP data show surface soil moisture in the Southeastern United States on Oct. 5, 2015 when large-scale flooding was experienced all over South Carolina.

SMAP data show surface soil moisture in the Southeastern United States on Oct. 5, 2015.

Devastating Carolina Floods Viewed by NASA's SMAP