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PREPARED BY:Uttam Pudasaini

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TABLE OF CONTENTS

Background Introduction Launch Objectives Design Concepts Focal Plane Major Band Of MODIS Sensor MODIS PRODUCTS Receiving station of MODIS

Receiving station at ICIMOD ,NEPAL

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A SHORT HISTORY

1983 – NASA began to explore the concept of a polar-orbiting platform to complement a manned polar-orbiting space station

Beginning as System Z, gained momentum with NASA’s proposed “Global Habitability” program

After Challenger disaster, polar space station disappeared as did manned servicing requirement

System Z became EOS – Earth Observing System Several instrument suites were developed Surface Imaging and Sounding Package (SISP) included the Moderate

Resolution Imaging Spectrometer

MODIS soon split into 2 concepts MODIS-N focused primarily on land and atmosphere sensing but

included some ocean bands MODIS-T (tilting) focused on ocean

Due to budget constraints, MODIS-T vanished, replaced by MODIS-N

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INTRODUCTION

The Moderate Resolution Imaging Spectroradiometer

(MODIS), one of the key instruments for NASA’s Earth

Observing System (EOS), was built by Raytheon Santa

Barbara Remote Sensing (SBRS)

MODIS Proto Flight Model (PFM) was launched on board

Terra spacecraft on 12/18/99 (first light on 02/24/00). http://terra.nasa.gov

MODIS Flight Model 1 (FM1) on Aqua spacecraft was

launched on 05/04/02 (first light on 06/24/02) http://eos-pm.gsfc.nasa.gov

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Contd…

MODIS (Moderate Resolution Imaging Spectrometer) is an imaging instrument flying at an altitude of 705 km on two satellites in NASA’s Earth Observing System: Terra and Aqua.

Two sun-synchronous, near-polar orbiting satellites called Terra (EOS AM-1) and Aqua (EOS PM-1) each carry a MODIS sensor Terra orbits from south to north with a morning equatorial crossing. Aqua orbits from north to south with an afternoon equatorial crossing

Flying on two satellites allows it to image the same area at different times of the day as well as cover the entire earth in one or two days.

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MODIS SCAN CAVITY AND OBCS

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LAUNCH OBJECTIVES

Unprecedented look at terrestrial, atmospheric, and ocean phenomenology for a wide and diverse community of users throughout the world.

To develop a valid global, interactive Earth system models able to predict global change accurately enough to assist policy makers in making sound decisions concerning the protection of our environment

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DESIGN CONCEPTS The Scan Mirror Assembly uses a continuously rotating double-sided

scan mirror to scan ±55-degrees

The MODIS instrument consists of a cross-track scan mirror, collecting optics and individual detector elements.

The swath dimensions of MODIS are 2330km (across track) by 10km (along track at nadir).

The along track swath dimension is due to the optical set-up as well as the scanning mechanism of MODIS.

In contrast to other scanning sensors like e.g. AVHRR, MODIS is observing within one scan ten lines of 1km spatial resolution (40 lines of 250m resolution and 20 lines of 500m resolution, respectively).

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MODIS FOCAL PLANE

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Major Bands of MODIS Sensors MODIS reflectance products focuses on Red, Blue, NIR AND MIR

Red band highly related with plant growth- to calculate EVI(enhanced) AND NDVI

Blue band Shortest and nosiest band to monitor atmospheric dust and other

particles travelling across the globe Eliminating atmospheric noise on the calculation of vegetation indices The bands help monitor changes in vegetation ,soil and atmosphere

that can influence in calculation of ecosystem variables like vegetation indices

NIR to visualize land and water (land reflects it while water bodies almost absorb it all)

MIR band to determine cloud properties vegetation and soil moisture

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Its coarse spatial resolution is designed to observe land, ocean, and atmospheric conditions at a regional and global scale.

The MODIS instrument provides high radiometric sensitivity (12 bit) in 36 spectral bands ranging in wavelength from 0.4 µm to 14.4 over a 2330 km swath.

20 Reflective Solar Bands (RSB): 0.4 - 2.2 microns

16 Thermal Emissive Bands (TEB) 3.5 - 14.5 microns

Bands are imaged at a nominal resolution of 250 m at nadir, with

five bands at 500 m, and the remaining 29 bands at 1 km.

CONTD…

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MODIS PRODUCTS Availability of a suite of products ranging from raw images to

highly processed products such as vegetation indices. Products are made on varying temporal schedules, some of

which are made as often as daily and every 8 days. Products are all archived and available, usually at no charge. MODIS products are organized into different processing

levels. Level 0 products are raw digital number images. Level 1 products include raw radiance and calibrated

radiance images. . Level 2 and 3 products have more processing and are

derived from lower level products.

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WHERE TO GET MODIS PRODUCTS???

 Level 1 and atmosphere products are available through the Level 1 and Atmospheric Archive and Distribution System (LAADS). http://ladsweb.nascom.nasa.gov/ 

Level 2 and 3 Land Products are available through Nasa’s Warehouse Inventory Search Too (WIST) and the Land Processes Distributed Active Archive Center (LPDAAC) Data Pool at the U. S. Geological Survey EROS Data Center (EDC). https://lpdaac.usgs.gov/get_data

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MODIS on board the Terra and Aqua spacecraft have the feature of Direct Broadcast capability together with an on board data storage and a transmission capability initiated by a ground command.

Direct Broadcast means that all raw data collected on board are immediately transmitted to ground.

Everybody on the world can listen to the downloaded data whenever the satellite is above their horizon assuming appropriate hard- and software equipment.

An Overpass Predictor delivered by NASA can be used to determine when there will be a TERRA / AQUA spacecraft overpass. More than 50 stations world-wide are now in operation for receiving MODIS data by Direct Broadcast.

RECEIVING STATION

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MODIS receiving station at ICIMOD,NEPAL

MODIS, a sensor onboard NASA's Terra and Aqua satellites, includes the mid-infrared, allows the application to identify the locations of thermal anomalies, and thus active fires.

The Forest Fire Detection and Monitoring System application uses real-time data downloaded by ICIMOD's MODIS receiving station.

The application also adds key information from SERVIR-Himalaya, including administrative unit (i.e., district), protected area identification, land cover, elevation, and slope, as well as road network data.

The MODIS data, with ancillary data, are used to identify the affected areas, provide district-level fire count statistics, and provide information such as the distance to the nearest road.

The user can overlay the MODIS data with, for example, the land cover data, to assess the damage caused by the forest fire.  A key feature of this application is its ability to send fire alerts via SMS/text message and/or emails to fire officials on their mobile telephones.

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References

http://modis.gsfc.nasa.gov/

http://www.icimod.org/?q=10092

Images used in my slides are snapshots from presentation slides of different individuals

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THANK YOU