Landsat Data Provision Satellite Data Enquiry Form




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Landsat Data Provision

Satellite Data Enquiry Form

Sensors


  • Multispectral Scanner (MSS): The MSS was a cross-track (whiskbroom) scanner that acquired imagery in four channels (2 visible, 2 near-infrared) at 79-meter resolution. The MSS was included on Landsat-1 through Landsat-5.

  • Thematic Mapper (TM): The TM was flown on Landsat-4 and Landsat-5. The TM is a cross-track scanner providing seven multispectral channels (3 visible, 1 near-infrared, 2 mid-infrared, 1 thermal-infrared) at 30-meter resolution (120-meter resolution for the thermal-infrared band).

  • Enhanced Thematic Mapper Plus (ETM+): The ETM+ instrument currently flying on Landsat-7 is similar to the earlier TM, but adds an extra 15-meter resolution panchromatic band, and improved resolution for the thermal-infrared band (60-meters).

The American series of Landsat satellites has provided high quality multi-spectral data since 1972. Over the years, millions of scenes have been acquired to form a world-wide archive of earth observation data.

Landsat 7 was launched successfully on 15th April 1999 and has enhanced features, including a 15 metre panchromatic band. It is an ideal, multi-purpose, cost-effective tool for a huge range of applications.

Landsat 1 - 3 carried a MSS (multi-spectral scanner) sensor and a RBV (return beam vidicon).

Landsat 4 and 5, launched in 1982 and 1984 respectively, have a MSS and TM (thematic mapper) sensor on board.

Landsat 6 unfortunately suffered an early demise and is now thought to be one of a select group of Pacific Ocean sea-floor sensors.

The satellite orbits at an altitude of 705Km. A full size Landsat MSS or TM scene covers an area of approximately 185Km by 175Km. The swathe of the sensor restricts the maximum width, and the contiguous orbit data is then divided up into nominal scenes. Digital products include raw and system corrected data.



Landsat 7 ETM+ Data

The ETM+ sensor on Landsat 7 has a number of enhanced features, including:



  • New panchromatic band with 15 metre spatial resolution, co-registered with the multi-spectral bands

  • Thermal infra-red band 6 has increased resolution from 120m to 60m, and now has two gain settings

  • Worldwide data - the solid state tape recorder can collect 100 images per day from anywhere in the world

A summary of the band information is contained in the table below.

 

Band Width

Spatial Resolution

Band 1

0.45 - 0.52µm (blue)

30 metres

Band 2

0.52 - 0.60µm (green)

30 metres

Band 3

0.63 - 0.69µm (red)

30 metres

Band 4

0.75 - 0.90µm (near infra-red)

30 metres

Band 5

1.55 - 1.75µm (infra-red)

30 metres

Band 6

10.4 - 12.50µm (thermal infra-red)

60 metres

Band 7

2.08 - 2.35µm (near infra-red)

30 metres

Band 8

0.52 - 0.90µm (green - near infra-red)

15 metres

Landsat 4 & 5

Landsat 4 and Landsat 5 data are essentially similar to the 30 metre spectral bands of Landsat 7 ETM+ data. Band 6 has a resolution of 120 metres. Landsat 4/5 data is typically more noisy than ETM+ data.

The USGS, who operate these satellites, have now decommissioned them and no further acquisitions are planned.

Landsat Band Combinations

The Landsat ETM+ subset image on the left covers an area of approximately 30 by 30 kilometres and is over the county of Kent, UK. A similar area on the right is of Ra's al Khaymah, United Arab Emirates. Click on the thumbnails to view larger (not full resolution) examples of typical band combinations used (they open in a new window)





Bands 3, 2, 1 in red, green, blue. This is a natural colour composition and tends to be used primarily for display posters or familiarising and orientating the non-expert user of satellite data. Also the band combination to use for shallow water applications such as bathymetry mapping and sediment load.





Bands 4, 3, 2 in red, green, blue. A familiar looking band combination if you are using SPOT XS or IRS multispectral data, as they only have these three band wavelengths. Although this band combination can be used for many applications, typically other combinations are used if other bands are available.





Bands 4, 5, 3 in red, green, blue. This band combination is used mostly for vegetation and land cover analysis, providing the greatest distinction between vegetation types. This band combination is one of the most useful over similar land cover types to Kent





Bands 7, 4, 2 in red, green, blue. This combination is used for geological applications as it provides the greatest distinction between rock types. Band 1 may be used instead of band 2 in the blue band if the image quality is good enough. This combination works well in arid areas, but poorly over areas like Kent.





Bands 7, 5, 3 in red, green, blue. A rarely used band combination but useful in providing a pseudo-natural colour image in some circumstances.





ASTER Data Provision

Satellite Data Enquiry Form

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) obtains high-resolution (15 to 90 square meters per pixel) images of the Earth in 14 different wavelengths of the electromagnetic spectrum, ranging from visible to thermal infrared light. We use ASTER data to create detailed maps of land surface temperature, emissivity, reflectance, and elevation.

ASTER was launched on the TERRA platform in December 1999.

The USGS have now started charging for ASTER data acquired by FTP. Even so, ASTER provides extremely cost effective coverage. Typically we use ASTER for geological and environmental interpretation, but it also has many other applications.

ASTER also has along track stereo capability. Accuracies obtainable from these stereo data are in the range of +/- 15m x,y and z with ideal conditions.



 

Band Width

Spatial Resolution

Band 1

0.52-0.60 (Green)

15m

Band 2

0.63-0.69 (Red)

15m

Band 3

0.76-0.86 (Near IR)

15m

Band 4

1.60-1.70 (SWIR)

30m

Band 5

2.145-2.185 (SWIR)

30m

Band 6

2.185-2.225 (SWIR)

30m

Band 7

2.235-2.285(SWIR)

30m

Band 8

2.295-2.365 (SWIR)

30m

Band 9

2.36-2.43 (SWIR)

30m

Band 10

8.125-8.475 (TIR)

90m

Band 11

8.475-8.825 (TIR)

90m

Band 12

8.925-9.275 (TIR)

90m

Band 13

10.25-10.95 (TIR)

90m

Band 14

10.95-11.65 (TIR)

90m

Swath width of the imagery is 60Km, with scenes covering a 60Km by 60Km area.


QuickBird Data Distribution

Satellite Data Enquiry Form

QuickBird was launched on the 18th October 2001. This is currently the highest resolution commercial satellite data available.

Example of a QuickBird pan sharpened 0.61 metre image of Tampa FL.



Example QuickBird pan sharpened 0.61 metre image of DC Airport.



Example of QuickBird 2.44 metre multispectral image of McMurdo Sound.



After an on-orbit calibration and commissioning period of about 90 days, QuickBird is now acquiring 61-centimeter (2-foot) resolution panchromatic (black and white) and 2.44-meter (8-foot) multispectral (color) imagery. At 61-centimeter resolution, buildings, roads, bridges and other detailed infrastructure become visible. The imagery will be used for a wide range of applications, focusing on the assessment and management of land, infrastructure, and natural resources.

QuickBird collects an industry-leading 16.5-kilometer (10.3-mile) swath of imagery that enables greater collection of large areas.



Rush Priority: The image acquisition window is 1 - 14 days, and the time from order to first acquisition is 48 hours. There is no cloud cover threshold. This service involves a price uplift of 100%

A summary of the multispectral band information is given below.



 

Band Width

Spatial Resolution

Band 1

0.45 - 0.52µm (blue)

2.44 - 2.88 metres

Band 2

0.52 - 0.60µm (green)

2.44 - 2.88 metres

Band 3

0.63 - 0.69µm (red)

2.44 - 2.88 metres

Band 4

0.76 - 0.90µm (near infra-red)

2.44 - 2.88 metres

More details and example imagery are at the DigitalGlobe website.

Infoterra offer QuickBird data through our official distributor agreement with Eurimage.



Ikonos Data Provision

Satellite Data Enquiry Form

The Ikonos-2 satellite was launched in September 1999 and has been delivering commercial data since early 2000. Ikonos is the first of the next generation of high spatial resolution satellites. Ikonos data records 4 channels of multispectral data at 4 metre resolution and one panchromatic channel with 1 metre resolution.  This means that Ikonos was the first commercial satellite to deliver near photographic high resolution satellite imagery of anywhere in the world.

Example of 1 metre Ikonos Pan imagery over Sydney, Australia.



Example of 4 metre Ikonos natural colour imagery over Cape Town, RSA.



Example 1 metre Ikonos pan sharpened image over Frankfurt Airport, Germany.



Radiometric Resolution: Ikonos data is collected as 11 bits per pixel (2048 gray tones). This means that there is more definition in the grey scale values and as a viewer you can see more detail in an image. In order to benefit from this additional information, you will need specialist image processing software.

Ikonos has both cross and along track viewing instruments which enable flexible data acquisitions and frequent revisiting capabilities - 3 days at 1 metre resolution and 1 to 2 days at 1.5 metre resolution.



 

Band Width

Spatial Resolution

Panchromatic

0.45 - 0.90µm

1 metre

Band 1

0.45 - 0.53µm (blue)

4 metres

Band 2

0.52 - 0.61µm (green)

4 metres

Band 3

0.64 - 0.72µm (red)

4 metres

Band 4

0.77 - 0.88µm (near infra-red)

4 metres

Pricing and timings of collecting / receiving data vary considerably depending on accuracy of product required, extent, area of the world and which ground receiving station collects the imagery. Contact us for availability and a quote.

DEMs are also available. These are quoted on an individual basis by Space


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