GIS SATELITES - LANDSAT

1. LANDSAT

2. INTRODUCTION
 Landsat was designed in 1960s by the combined effort of NASA and US.
 Launched in 1972 as the 1st tailored Satellite, specifically for broad scale
observation of the Earth’s Land areas.
 Seven satellite have been launched successfully, namely Landsat -1 to -5
and Landsat -7 & 8
 Landsat-6 suffered a launch failure.
 Five different types of sensor used namely RBV,MSS,TM,ETM and
ETM+.

3. OBJECTIVE
 To acquire data about earth resources on a
-Systematic,
-Repetitive,
-Medium resolution,
-Mulitispectral basis's
 All data can be collected in accordance with an
“open skies” principle.
 Meaning ,there would be nondiscriminatory access to data collect
anywhere in the world

4. LANDSAT 1-2-3
SATELITE LAUNCHED END OF SERVICE SENSORS
LANDSAT 1 23 JULY 1972 6 JAN 1978 MSS (1-3)
RBV (4-7)
LANDSAT 2 22 JAN 1975 25 JAN 1982 MSS (1-3)
RBV (4-7)
LANDSAT 3 5 MARCH 1978 3 MARCH 1983 MSS (1-3)
RBV (4-7)

5. CHARACTERISTICS
•Butterfly shaped , sun-synchronous
•3 meter tall , 1.5 m in Diameter with solar panels extending about 4 meter
•Satellite weighed about 815 Kg
•Altitude 919 Km
•Orbital inclination is 99 degree
•Orbits cycle is 18 days
•Orbital period is 103 min. or 14 orbits per day
•Ground track speed is 6.46 km/sec.
•Cross the equator at a time 9.30 to 10.00am

6. LANDSAT 1
LANDSAT 2
LANDSAT 3

7. LANDSAT 4 AND 5
SATELLITE LAUNCHED END OF SERVICE SENSORS
LANDSAT 4 6 JULY 1982 Transmission of TM data
failed in august 1993
MSS (1-4)
TM (1-7)
LANDSAT 5 1 MARCH 1984 Transmission by direct
downlink only
MSS (1-4)
TM (1-7)

8. CHARACTERISTICS
 Like Landsat,1-3 Landsat,4-5 are repetitive, circular, sun-
synchronous, near polar orbits.
 Altitude 705Km
 Orbital inclination is 98.2 degree
 Orbital period is 99 min. or 14.5 orbits per day.
 Orbits cycle is 16 days
 Cross the equator on north-south portion of each orbit at a time
9.45am 10.00am local sun time.

10. LANDSAT 6-7-8
SATELLITE LAUNCHED END OF
SERVICE
SENSORS
LANDSAT 6 5 OCT 1993 Failure upon launch ETM+ (1-7 plus
pan-chromatic )
LANDSAT 7 15 APRIL 1999 Still active ETM+ (1-7 plus
pan-chromatic )
LANDSAT 8 11 FEB 2013 Still active Operational land
imager (OLI)

11. LANDSAT -7
 Landsat-7 is a three-axis stabilized platform caring a single
nadir-pointing instrument the ETM+ .
 It is bases on scanning technology despite the fact that linear
“push-broom” technology.
 It acquires every day time scene on every pass over the United
States (US).
 It has similar orbits characteristic to Landsat-4 and-5.

12. LANDSAT- 8
 Sun-synchronous orbit at an altitude of 705 km (438 mi)
 233 orbit cycle; covers the entire globe every 16 days
(except for the highest polar latitudes)
 Inclined 98.2° and Circles the Earth every 98.9 minutes
 Power provided by a single 9 x 0.4 meter solar array and
one 125 Ampere-Hour (AHr), Nickel-Hydrogen (NiH2)
battery

14. LANDSAT SENSORS
 Sensors:
 sensors that observe the earth and then transmit
information by microwave signals to ground stations that
receive and process data for dissemination to a
community of data users.
 Landsat sensors recorded energy in the visible & near
Infrared spectrum.

15. RETURN BEAM VIDICON (RBV)
 RBV have high spatial resolution and geometric accuracy but lower spectral and radiometric
resolution.
 It is camera like instrument .
 Position of feature would be accurately represented.
 RBV sensor could acquire an image every 25 seconds to produce a series of images with a
small forward overlap.
 Function of RBV was primarily to provide data for accurate measurement of position and
distance.
•Disadvantage:RBV operations were plagued with various technical problems.

16. MSS
 MSS system were the 1stglobal monitoring systems of producing multispectral
data in digital format.
 It covered several tens of billions of square Kms of the earth' surface.
 MSS sensors use a whisk-broom design.
 It is an optical mechanical system in which a mirror scans the terrain perpendicular
to the flight direction.
 It scans focuses radiant flux from terrain onto discrete detectors elements.
 These detectors convert the radiant flux into electronic signals .
 It has four sets of filters and detectors.

17. WORKING
 MSS scanning mirror oscillate through an angular displacement of
±5.78°off-nadir.
 So 11.56°field of view resulted in a swath 185 Km for each orbit .
 When not viewing the earth ,the MSS detectors were exposed to internal
light and sun calibration sources .
 One scene has about 7.6 million pixels ,recorded in 27 seconds.
 Landsat scene are referenced by orbital path (numbered 0-255 east to west)
and row (numbered from north to south, with row 60 at the equator).

18. THEMATIC MAPPER(TM)
 TM was based upon the same principle as the MSS, but had more complex design.
 It provides finer spatial resolution , improved geometric fidelity, greater
radiometric detail and more detailed spectral information.
 Objective:
 The objectives were to asses the performance of TM ,to provide ongoing stability
of MSS and continue to foreign data reception.
 TM with MSS maintained a high degree of stability in orientation as a means of
improving geometric qualities of the imagery.

19. ENHANCED THEMATIC MAPPER(ETM+)
 It is designed to extend the capabilities of previous TMs by adding most
improvements to the TM’s original design.
 ETM+ has a 15 m panchromatic channel.
 Like TM,ETM+ scans 16 simultaneous lines per non-thermal band (32
panchromatic lines ).
 Data acquisition by the ETM+ is directed by the mission goal of acquiring
and updating periodically a global achieve of day time , substantially cloud
free images of land areas.

20. LANDSAT 9
 PLANNED LAUNCHING: DECEMBER 2020
 Landsat 9 will have a higher imaging capacity than previous
Landsat satellites (~740 scenes/day), allowing for more valuable
data to be added to the Landsat global land imaging archive.
 It handles power, propulsion, solid state recorder (SSR), space to
ground communications, and housekeeping.
 Sun-synchronous orbit at an altitude of 438 miles (705 km)
 SENSOR:Operational Land Imager-2 (OLI-2)
Thermal Infrared Sensor-2 (TIRS-2)