U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2005–3060

May 2005

Land Remote Sensing

Earth Observing-1 Extended Mission

Printed on recycled paper

Overview

Since November 2000, the National Aeronautics and Space Administration (NASA) 

Earth Observing-1 (EO-1) mission has demonstrated the capabilities of a dozen spacecraft sensor and communication innovations. 

Onboard the EO-1 spacecraft are two land 

remote sensing instruments. The Advanced 

Land Imager (ALI) acquires data in spectral 

bands and at resolutions similar to Landsat. 

The Hyperion instrument, which is the first 

civilian spaceborne hyperspectral imager, 

acquires data in 220 10-nanometer bands covering the visible, near, and shortwave-infrared bands. The initial one-year technology 

demonstration phase of the mission included a 

detailed comparison of ALI with the Landsat 

Enhanced Thematic Mapper Plus (ETM+) 

instrument. Specifications for the Operational 

Land Imager (OLI), the planned successor to 

ETM+, were formulated in part from performance characteristics of ALI. 

Recognizing the remarkable performance 

of the satellite’s instruments and the exceptional value of the data, the U.S. Geological 

Survey (USGS) and NASA agreed in December 2001 to share responsibility for operating 

EO-1. The extended mission continues, on 

a cost-reimbursable basis, as long as customer sales fully recover flight and ground 

operations costs. As of May 2005, more than 

17,800 scenes from each instrument have 

been acquired, indexed, archived, and made 

available to the public.

Applications

Multispectral and hyperspectral data from 

EO-1 are valuable for a variety of applications. Hyperion data contribute to fire monitoring and prediction by providing detailed 

spectral definition of forest composition and 

structure, forest canopy, and underlying fire 

fuels. The mapping of active fire burns has 

been enhanced by the ability to image crossFigure 1. Left: Hyperion centered image collect of Mt. Fuji, Japan, acquired on February 9, 2003. (Scene ID: EO1H1080352003040110PZ) Middle: ALI centered image collect of Mt. Fuji acquired on March 4, 2003. (Scene ID: EO1A1080352003063110KO) Right: EO-1 ALI and Hyperion data are suitable for studying various applications all over 

the world.

track and by the multispectral improvements 

of the ALI instrument.

For many years multispectral imagery 

has been the staple data for land use and land 

cover classification. Hyperion has proven 

to be beneficial for discriminating coral/sea 

grass in shallow coral reefs and monitoring 

ecosystem function. Hyperion also has been 

effective for identifying basic mineral spectra 

in arid environments. EO-1 data are a representative prototype for future remote sensing 

instruments, offering the global science community an important transitional reference for 

applications involving next generation sensors 

(Figure 1).

Sensor Capabilities

The EO-1 extended mission operates 

within constraints imposed by its technology pioneering origins, but it also provides 

unique and valuable imaging capabilities. The 

spacecraft has the ability to acquire a target 
scene three times in a 16-day period with its 

cross-track pointing capability (Figure 2).

ALI has an improved signal-to-noise ratio 

in comparison to Landsat 7 ETM+, which is 

due in large part to ALI’s pushbroom scanning 

technology (Figure 3).

The ALI instrument also has additional 

spectral coverage and greater radiometric 

dynamic range compared with ETM+, yet ALI 

data can still be cross-correlated with ETM+ 

data (Figure 4).

ALI can image a coincident patch on the 

ground simultaneously with Hyperion

(Figure 5).

Extended Mission Roles

NASA and the USGS are operating the 

EO-1 mission as economically as possible, 

leveraging the infrastructure and technical 

strengths of each agency. The NASA Goddard 

Space Flight Center (GSFC) in Greenbelt, 

Maryland, manages the mission and operates the spacecraft. The GSFC coordinates 

data collection among a network of polar and 

U.S. ground stations. The GSFC periodically 

adjusts the spacecraft orbit to ensure that it 

follows the Landsat 7 satellite by one minute. 

The spacecraft has sufficient fuel to remain 

in its current Worldwide Reference System-2 

(WRS-2) orbit through 2005, at which time 

NASA will determine when to decommission 

the spacecraft and conduct de-orbit maneuvers. 

The U.S. Geological Survey (USGS) National 

Center for Earth Resources Observation and 

Science (EROS) is responsible for acquisition 

scheduling, data reception, order processing, 

acquisition cataloging, data archiving, product 

generation, and distribution. The USGS will 

maintain the entire EO-1 collection in its 

long-term archive of global land data following 

decommissioning.

Extended Mission Goals

• Sustain and enhance USGS and NASA 

research and development of applications 

for hyperspectral and multispectral data. 

• Promote opportunities in the remote sensing community to apply evolving imaging 

technology for government, scientific, and 

industry applications. 

• Add unique land remote sensing data to 

the USGS National Satellite Land Remote 

Sensing Data Archive. 

• Characterize long-term performance of 

EO-1 advanced technology sensors.

Data Products and Availability

ALI data are available as systematic 

radiometrically (Level 1R) and geometrically 

(Level 1G) corrected products. Hyperion data 

are available as radiometrically (Level 1R) 

corrected products. 

Archived data products can be searched 

and ordered online at:

http://earthexplorer.usgs.gov and

http://glovis.usgs.gov

Data Acquisition Requests (DARs) can be 

submitted online at:

http://eo1.usgs.gov/DARInstructions.php

EO-1 provides the capability for a quick 

product turnaround by providing priority 

tasking and expedited processing. Additional 

costs are required for both of these services.

For More Information

EO-1 products, prices, sensors, and 

acquisition schedule can be found at:

http://eo1.usgs.gov

Technical information about the EO-1 

mission, satellite, and sensors is available at: 

http://eo1.gsfc.nasa.gov

Contact Information

Customer Services

USGS National Center for EROS

Mundt Federal Building

Sioux Falls, SD 57198-0001

Phone: 800-252-4547

Phone: 605-594-6151

TDD: 605-594-6933

Fax: 605-594-6589

Email: custserv@usgs.gov

Figure 2. EO-1 flies in formation with Landsat 7,

trailing Landsat 7 by approximately one minute. 

Pointable sensors that are onboard EO-1 allow 

off-nadir viewing capability outside of the current 

(nadir) WRS-2 path.

Figure 5. This graphic displays the EO-1 Hyperion 

(white) and ALI (yellow) ground tracks for a 42 

and 185 kilometer acquisition superimposed on a 

Landsat WRS-2 path/row (blue). Nadir pointing is 

displayed for the WRS-2.

Figure 4. EO-1 Spectral Ranges

Swath Width

IFOV

FOV

Back and Forth

Scan Line Flight Direction

Scan Direction

Whiskbroom Scanner

Swath Width FOV

Instantaneous

Scan Line

Pushbroom Scanner

Flight Direction

(Landsat 7) (EO-1)

Figure 3. Comparison of EO-1 ALI and Landsat 7 ETM+

EO-1 ALI and Hyperion Spectral Ranges

Nanometers

S

e

n

s

ors

300 800 1300 1800 2300 2800

Hyperion

ALI

Band 9

Band 8

Band 7

Band 6

Band 5

Band 4

Band 3

Band 2

Band 1

Panchromatic Band

Band 1 Band 220