Space Oblique Mercator Projection
Jun 26, 2014Space Oblique Mercator Projection

To continually map the Earth’s surface using Landsat data, an entirely new projection had to be created. This new projection was created by John Parr Snyder and is known as the Space Oblique Mercator (SOM) projection. This projection has been referred to as, “one of the most complex projections ever devised” by Library of Congress cartographic historian, John W. Hessler.

Spacecraft orbit of Landsat 1, 2, and 3.
Jan 22, 2013Landsat Spacecraft Orbit

Source: The Landsat Tutorial Workbook This schematic appears in The Landsat Tutorial Workbook: Basics of Satellite Remote Sensing, written by Dr. Nicholas Short and published by the NASA Scientific and Technical Information Branch in 1982. Dr. Short writes, “The Landsat-1 spacecraft was launched on July 23, 1972, and positioned in the orbit shown in [this figure]. […]

Schematic diagram illustrating the seasonal illumination variations on a sun-synchronous orbit.
Jan 22, 2013Seasonal Illumination Variations

Source: Landsat-6 Programming and Control Handbook This schematic appears in the Landsat-6 Programming and Control Handbook that was prepared by Martin Marietta Astro Space in 1993. Like all of the Landsat satellites, Landsat-6 would have been in a sunscreen orbit had its launch been successful. The L6 Handbook tells us, “Establishment of the sun-synchronous orbit provides for […]

A Transverse Mercator projection.
Jan 22, 2013Transverse Mercator Projection

Source: 1983 Landsat Short Course Lecture This schematic appears in the handbook that accompanied the1983 Landsat Short Course lecture on “TM Data Processing and Correction” that was given by Jeff Dozier of UCSB. To continually map the Earth’s surface using Landsat data, an entirely new projection had to be created. This new projection was created by […]

Diagram showing the flight profile of ERTS-1.
Jan 22, 2013ERTS Flight Profile

Source: Earth Resources Technology Satellite Reference Manual This schematic appears in the ERTS Reference Manual that was prepared by General Electric prior to the Landsat 1 (ERTS-1) launch in 1972. The schematic shows the Landsat 1 flight profile, from liftoff (0) to spacecraft separation (10). The manual tells us, “an all-inertial guidance system, consisting of an inertial […]

Schematic diagram illustrating the geometry of a sun-synchronous orbit for the morning descending node of Landsat.
Jan 22, 2013Geometry of a Sun-Synchronous Orbit

Source: Landsat-6 Programming and Control Handbook This schematic appears in the Landsat 6 Programming and Control Handbook that was prepared by Martin Marietta Astro Space in 1993. Like all of the Landsat satellites, Landsat 6 would have been in a sun-synchronous orbit had its launch been successful. The L6 Handbook tells us, “for a nominal sun-synchronous orbit […]

Schematic diagram showing distribution of reflected radiation from a diffuse reflector.
Jan 22, 2013A Lambertian Reflector

Source: The Landsat Tutorial Workbook This schematic diagram depicts the behavior of a perfectly diffuse, or Lambertian, surface. This diagram appears in the The Landsat Tutorial Workbook: Basics of Satellite Remote Sensing written by Dr. Nicholas M. Short and published by the NASA Scientific and Technical Information Branch in 1982. Dr. Short writes, “Consider a bundle of […]