The Landsat Program is a joint 

effort of the U.S. Geological Survey 

(USGS) and the National Aeronautics 

and Space Administration (NASA) 

to gather Earth resource data using 

a series of satellites. NASA was 

responsible for developing and 

launching the spacecrafts. The USGS 

is responsible for flight operations, 

maintenance, and management of all 

ground data reception, processing, 

archiving, product generation, and 

distribution. A primary objective of 

the Landsat Program is to ensure a 

collection of consistently calibrated 

Earth imagery.

Landsat’s mission is to establish and 

execute a data acquisition strategy 

that ensures the repetitive acquisition 

of observations over the Earth’s land 

mass, coastal boundaries, and coral 

reefs and to ensure that the data 

acquired are of maximum utility in 

supporting the scientific objective of 

monitoring changes in the Earth’s 

land surface.

A Brief History of the Landsat 

Program

In the mid-1960s, stimulated by 

success in planetary exploration 

using unmanned remote sensing 

satellites, the Department of the 

Interior, NASA, the Department of 

Agriculture, and others embarked 

on an ambitious initiative to develop 

and launch the first civilian Earthobserving satellite to meet the needs 

of resource managers and earth 

scientists. The USGS assumed 

responsibility for archiving the data 

acquired by the new program and 

for distributing the anticipated data 

product. 

On July 23, 1972, NASA launched 

the first in a series of satellites 

designed to provide repetitive global 

coverage of the Earth’s land masses. 

Landsat, originally named “ERTS” 

for Earth Resources Technology 

Satellite, has continued to provide 

high-quality, moderate-resolution 

data depicting the land and coastal 

regions of the planet. As a result of 

subsequent satellites launched in the 

Landsat series, there is a continuous 

set of Landsat data from mid-1972 

until the present.

NASA was responsible for operating 

the system through the early 1980s, 

with the USGS having responsibility 

for archiving the data and producing 

image products. In January 1983, a 

plan was made to transfer operation 

of the Landsat Program to the private 

sector. The first step of this plan 

required transfer of the Landsat 

system operation to the Landsat 

Commercialization Division of the 

National Oceanic and Atmospheric 

Administration (NOAA). In October 

1985, the Earth Observation Satellite 

Company (EOSAT), now Space 

Imaging, assumed responsibility for 

Landsats 4 and 5 under contract to 

NOAA. This contract was transferred 

to the USGS in 1998, but Space 

Imaging continued to operate 

Landsats 4 and 5 until mid-2001, 

when it returned responsibility to 

the U.S. Government. Throughout 

these changes, the USGS retained 

primary responsibility for long-term 

preservation as the Government 

archive of Landsat data. The Landsat 

Program underwent additional 

management changes with the 

passage of the Land Remote Sensing 

Policy Act of 1992. This act, 

which returned Landsat Program 

management to the Government 

under joint management of the 

Department of Defense (specifically, 

the U.S. Air Force (USAF)) and 

NASA, created the legislative 

mandate for the National Satellite 

Land Remote Sensing Data Archive 

and assigned this responsibility to the 

Department of the Interior. 

Landsat Program management 

structure changed repeatedly from 

1992 through 1998, from 

NASA/USAF/USGS to 

NASA/NOAA/USGS to 

NASA/USGS. The USGS assumed 

operational responsibility for the 

Landsat Program in 1999, but 

NASA continued flight operations 

for Landsat 7 until 2000, when the 

USGS implemented a new flight 

operations contract. In mid-2001, the 

USGS also assumed responsibility 

for Landsats 4 and 5 flight 

operations.

U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet 023-03

March 2003

Landsat: A Global Land-Observing Program
Characteristics of the Landsat 

System

All Landsat satellites have flown in 

a Sun-synchronous orbit. This allows 

the satellite to maintain a constant 

orientation between the Earth and the 

Sun. As a result, the mean Sun time 

at each point in the orbit remains 

fixed. For example, equatorial 

crossing times range from 8:30 a.m. 

(local time) for Landsat 1, to 9 a.m. 

for Landsat 2, and to approximately 

10:00 a.m. for Landsats 5 and 7. 

Landsats 1, 2, and 3 operated in a 

near-polar orbit at an altitude of 920 

km. These satellites circled the Earth 

every 103 minutes, completing 14 

orbits a day. It took 18 days and 251 

overlapping orbits to provide nearly 

complete coverage of the Earth’s 

surface with 185-km image swaths. 

The primary sensor aboard Landsats 

1, 2, and 3 was the multispectral 

scanner (MSS). The MSS sensor 

scanned the Earth’s surface across 

the satellite track as the satellite 

moved in its descending (north-tosouth) orbit over the sunlit side of the 

Earth. The combination of scanning 

geometry, satellite orbit, and Earth 

rotation produced the global coverage 

necessary for studying land surface 

change. The resolution of the MSS 

sensor was approximately 80 m, with 

radiometric coverage in four spectral 

bands from the visible green to the 

near-infrared (IR) wavelengths. The 

MSS sensor on Landsat 3 had a fifth 

band in the thermal-IR wavelength.

Landsats 4 and 5 carried both the 

MSS and a new, improved thematic 

mapper (TM) sensor. The MSS 

sensors onboard Landsats 4 and 5 

were identical to the one that was 

carried on Landsat 3. The MSS 

and TM sensors detect reflected or 

emitted energy from the Earth in 

the visible and IR wavelengths. TM 

bands 1-5 and 7 collect reflected 

energy; band 6 collects emitted 

Satellite Launched Decommissioned Sensors

Landsat 1 July 23, 1972 January 6, 1978 MSS and RBV*

Landsat 2 January 22, 1975 February 25, 1982 MSS and RBV*

Landsat 3 March 5, 1978 March 31, 1983 MSS and RBV*

Landsat 4 July 16, 1982 June 30, 2001 MSS and TM

Landsat 5 March 1, 1984 (Operational) MSS and TM

Landsat 6 October 5, 1993 (Did not achieve orbit) ETM**

Landsat 7 April 15, 1999 (Operational) ETM+**

*The return beam vidicom (RBV) was essentially a television camera and did not achieve the popularity of the MSS sensor.

**The sensor onboard Landsat 6 was called the enhanced thematic mapper (ETM). Landsat 7 carries the enhanced thematic 

mapper plus (ETM+)

Value of the Acquisition Cycle for Images - 

Olympic Peninsula, Washington

These images were taken by Landsats 5 and 7 from June through August 2001. They illustrate why regular repeated coverage by multiple satellites 

helps to ensure cloud-free images are acquired for users.
Band Designation

The TM sensor (Landsats 4 and 5) and the ETM+ sensor (Landsat 7) operate in seven spectral bands, shown in the 

table below:

Spectral Bands Use

1 blue-green Useful for bathymetric mapping and distinguishing soil from vegetation and deciduous from 

 coniferous vegetation.

2 green Emphasizes peak vegetation, which is useful for assessing plant vigor.

3 red Discriminates vegetation slopes.

4 Reflected IR Emphasizes biomass content and shorelines.

5 Reflected IR Discriminates moisture content of soil and vegetation; penetrates thin clouds.

6 Thermal IR Useful for thermal mapping and estimated soil moisture.

7 Reflected IR Useful for mapping hydrothermally altered rocks associated with mineral deposits.

Note: Landsat 7 also carries a panchromatic band (visible through near infrared) with 15-m resolution for “sharpening” of 

multispectral images. 

The four MSS band designations are numbered differently for Landsats 1, 2, and 3 and Landsats 4 and 5:

Landsats 1,2, & 3 Landsats 4 & 5 

Spectral Bands Spectral Bands Use

Band 4 green Band 1 green Emphasizes sediment-laden water and delineates areas of shallow 

 water.

Band 5 red Band 2 red Emphasizes cultural features.

Band 6 near IR Band 3 near IR Emphasizes vegetation boundary between land and water, and 

 landforms.

Band 7 near IR Band 4 near IR Penetrates atmospheric haze best, emphasizes vegetation, boundary 

 between land and water, and landforms.

energy. The TM sensor has a 

spatial resolution of 120 m for the 

thermal-IR band and 30 m for the 

six reflective bands. The newest 

satellite in the series, Landsat 7, 

carries the enhanced thematic 

mapper plus (ETM+), with 30-m 

visible and IR bands, a 60-m spatial 

resolution thermal band, and a 15-

m panchromatic band. Failure of 

onboard electronics halted data 

collection by Landsat 4 in 1993. 

The spacecraft was maintained 

on orbit as a test bed until it was 

decommissioned in June 2001. 

Landsats 5 and 7, the two remaining 

operational satellites, orbit at an 

altitude of 705 km, and each provides 

a 16-day, 233-orbit cycle. (The two 

satellite orbits are offset, allowing 8-

day repeat coverage.) These satellites 

were also designed to collect data 

over a 185-km swath.

Applications of Landsat Data

Landsat data have been used by 

government, commercial, industrial, 

civilian, military, and educational 

communities in the United States 

and worldwide. They support a wide 

range of applications in such areas as 

global change research, agriculture, 

forestry, geology, resource 

management, geography, mapping, 

water quality, and oceanography.

Landsat 7 is providing the global 

science community with a wealth of 

data. As of January 2003, the three 

ground stations managed by the 

USGS had collected over 300,000 

Bolivia clear cutting - 1987 Bolivia clear cutting - 2000
scenes for the U.S. archive; more 

than 30 percent have 10-percent 

or less cloud cover. This network 

of ground stations allows virtually 

global coverage.

The consistency of the Landsat data 

over the three decades of acquisition 

offers opportunities to compare land 

cover changes over periods of time. 

The advances made in data reception 

and processing permit rapid access 

to imagery in times of natural or 

manmade disaster. For example, 

resource managers in Colorado 

battling a large forest fire were able 

to receive Landsat 7 data in the field 

within hours of an overpass.

Landsat Data Continuity Mission 

Landsat has provided the science 

community with an important archive 

of land feature observations. Plans 

are underway for the next generation 

of land-observation systems. The 

Landsat Data Continuity Mission 

(LDCM) is a cooperative effort 

between the U.S. Government and 

the private sector to ensure continuity 

of Landsat-like data well beyond the 

duration of the Landsat 7 mission. 

Landsat 7, with its nominal design 

life to end in mid-2004, is currently 

expected to last at least through 

2008. After a launch scheduled for 

late 2006, LDCM is expected to 

begin full operations early in 2007. 

At that point, the Government will 

be purchasing–from the commercial 

satellite’s owner/operator–seasonal 

global datasets of Landsat-like scenes 

at the average rate of 250 per day 

(the same rate as Landsat 7 scene 

acquisitions by the USGS). All such 

Government-procured LDCM data 

will be delivered to the USGS EROS 

Data Center for archive, access, 

and public distribution without user 

restrictions, as with the Landsat 

7 Program. The scientific-data 

procurement contract will be in effect 

through 2012, with an option for a 5-

year extension.

Information

Information about the Landsat 

Program and Landsat holdings in 

the U.S. archive can be found at: 

landsat7.usgs.gov.

Or by contacting: 

EROS Data Center

Customer Services

Mundt Federal Building

Sioux Falls, SD 57198

Telephone: 605-594-6151

Fax: 605-594-6589

E-mail: custserv@usgs.gov

Information about the Land Remote 

Sensing Program is available at: 

remotesensing.usgs.gov.

Information about LDCM is available 

at: ldcm.usgs.gov.

For information on other USGS 

products and services, call 1-888-

ASK-USGS or visit the USGS 

Geography Products Web site at 

erg.usgs.gov/isb/pubs/pubslists/.

For additional information, visit the 

ask.usgs.gov Web site or the USGS 

home page at www.usgs.gov.