Download Remote Sensing

Remote Sensing
Space-based Earth exploration and planetary
exploration began with the International
Geophysical Year (IGY) which was also the
beginning of the space race (1957)
IGY was an 18-month international scientific
research project that spanned 1957-1958

Research included Earth sciences: aurora and
airglow, cosmic rays, geomagnetism, gravity,
ionospheric physics, longitude and latitude
determinations (precision mapping), meteorology,
oceanography, seismology and solar activity
Remote Sensing

Instruments for the early
Explorer program were
improved and modified for
lunar and planetary
exploration in the Pioneer
(lunar) and Mariner (Venus,
Mars) missions
 Explorer 1 was America’s
first satellite
 Continued through
Explorer 78
 Launched in 2000
Remote Sensing

Remote sensing is traditionally used for
Earth observation, but also applies to
planetary exploration


The same or similar or instruments used for both
Measurements at a distance use
electromagnetic (EM) sensors




Radio, microwave
IR
Visible
UV
Remote Sensing

Sampling (in situ) measurements

Generally for accurate measurements of
composition and abundance

Include:
 Mass spectrometers
 Atmospheric particle detectors
 Surface analysis
 Particle and EM radiation detectors
Remote Sensing

Sampling (in situ)
measurements on
Earth can be relatively
inexpensive

In situ measurements
on planets/moons are
the most expensive
space exploration
projects
Earth observation



Ground-based
Airborne
Space-based
Remote Sensing
Atmosphere is an important element in Earth
observation
1. Direct atmospheric studies


Complex circulation effects climates in many
ways
Changes in circulation important
2. Atmospheric interaction includes:




Absorption
Emission
Chemical interactions
Water (liquid and vapor)
Remote Sensing
Atmospheric absorption spectra
Mostly due to H2O, O2, CO2
Remote Sensing
Space-based observations
EM radiation sensors include:

Imaging data

Spectral data

Spectral imaging data

Color television is an example of
sequential spectral (color) images
Remote Sensing
Spectral data
example
(Chandra X-ray
Telescope data)
Remote Sensing
Spectral image
data mosaic
Remote Sensing
Spectral image data of aurora
Remote Sensing – Spectral Bands
Remote Sensing – Spectral Bands
Radio band

Various definitions of frequency range


0 - 300 MHz (1 MHz = 106Hz)
0 - 1 GHz (1GHz = 109Hz)

Lowest EM frequencies

Often used for upper-atmosphere and
ion/electron measurements
Remote Sensing – Spectral Bands
Microwave band

300 MHz - 300 GHz

Used for:




Surface feature identification
Atmospheric layer measurements
Radio astronomy
Synthetic aperture (imaging) radar
Remote Sensing – Spectral Bands
Infrared band

300 GHz - 400,000 GHz (400 THz)


1 THz = 1 Tera Hertz = 1012Hz = 1,000 GHz
Used for:







Surface feature identification
Atmospheric layers and thunderstorm activity
Atmospheric energy exchange
Energy absorption or emission in atmosphere
Vegetation characteristics
Planetary heat flow
Stellar and galactic activity
Remote Sensing – Spectral Bands
Visible band

4x1014Hz - 8x1014Hz (400 THz - 800 THz)

Used for:





Surface feature identification
Clouds & precipitation
Vegetation layers
Ocean surfaces
Mineral identification
Remote Sensing – Spectral Bands
UV band

7.5x1014Hz - 3x1016Hz

Used for:




Upper atmosphere measurements
Solar emissions
Stellar characteristics including star birth
and star death
Galaxy characteristics
Remote Sensing – Spectral Bands
X-ray band

1016 - 1019Hz

Used for:



Planetary surface composition from
radioisotope emission spectra
Stellar activity (primarily for stars, including our
sun, and galaxies)
Excited (hot) gas in the solar system,
surrounding stars, in galaxies, and between
galaxies
Remote Sensing – Spectral Bands
Gamma-ray band

1019Hz and higher (no defined maximum)

Used for:




Planetary surface composition from
radioisotope emission spectra
Used to identify energetic stars and galaxies
Supernova detection
Neutron star formation
Applications
Agriculture






Crop type classification
Crop condition
assessment
Crop yield estimation
Mapping of soil
characteristics
Mapping of soil
management practices
Compliance monitoring
(farming practices)
Applications
Forestry






Forest mapping
Clear-cut mapping
Forest inventory
Deforestation
evaluation
Watershed
evaluation
Coastal forest
protection
Applications
Geology













Bedrock mapping
Surface deposit mapping
Surface deformation &
changes
Sedimentary mapping
Structural mapping
Mantle & crust motion
Volcanic evolution
Event mapping
Mineral exploration
Hydrocarbon exploration
Environmental geology
Geo-hazard mapping
Planetary mapping
Applications
Ice Pack & Hydrology








Wetlands mapping &
monitoring
Soil moisture
estimation
Snow pack evaluation
River & lake ice
Flood mapping &
monitoring
Glacier dynamics
River delta changes
Irrigation evaluation &
monitoring
Applications
Environmental planning







Atmosphere
Oceans
Public health
Coastal changes
Industrialization
Forests
Rivers, lakes &
estuaries
Applications
Disaster Planning &
Evaluation






Floods
Tornadoes
Hurricanes/cyclones
Fires
Earthquakes
Droughts
Applications
Weather





Forecasting
Adverse weather
planning
Aviation & marine
weather
Global atmosphere
Sun-Earth
interactions
Applications
Planetary
Observations

Surface
characteristics






Geology
Composition
Activity
Atmosphere
Environment
Solar interactions