AFP-675 was a Space Shuttle

Space Shuttle

The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

 experiment package that was carried into orbit on Discovery

Space Shuttle Discovery

Space Shuttle Discovery is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States, and was operational from its maiden flight, STS-41-D on August 30, 1984, until its final landing during STS-133 on March 9, 2011...

as part of STS-39

STS-39

-Mission parameters:*Mass:**Orbiter landing with payload: **Payload: *Perigee: *Apogee: *Inclination: 57.0°*Period: 89.6 min-Mission highlights:...

.

AFP-675 consisted of six experiment packages mounted on a pallet in the Discovery's cargo bay. The total weight of the package was 5,080 kilograms (11,200 lb). The objectives of the project were:

1. To obtain data in several wavelength regions to support the development of Department of Defense
   United States Department of Defense
   The United States Department of Defense is the U.S...
   
    (DOD) systems
2. To validate technologies for DOD applications
3. To validate the use of man as an autonomous experimenter in space
4. To demonstrate the cost effectiveness of performing DOD experiments on reusable systems.

The experiments

Cryogenic Infrared Radiance Instrumentation for Shuttle

The Cryogenic Infrared Radiance Instrumentation for Shuttle (CIRRIS 1A) experiment was designed to measure the spectral, spatial, and temporal properties of the Earth's limb (edge). The primary instruments in this experiment were a Michelson spatial interferometer

Michelson interferometer

The Michelson interferometer is the most common configuration for optical interferometry and was invented by Albert Abraham Michelson. An interference pattern is produced by splitting a beam of light into two paths, bouncing the beams back and recombining them...

 and a spatial radiometer

Radiometer

A radiometer is a device for measuring the radiant flux of electromagnetic radiation. Generally, the term radiometer denotes an infrared radiation detector, yet it also includes detectors operating on any electromagnetic wavelength....

. Infrared radiation was collected through a cryogenically cooled telescope that was controlled from the flight deck. The principal investigator

Principal investigator

A principal investigator is the lead scientist or engineer for a particular well-defined science project, such as a laboratory study or clinical trial....

 (PI) for the instrument was Dr. Robert R. O'Neil of the Phillips Laboratory.

Far Ultraviolet Cameras

The Far Ultraviolet Cameras experiment was to capture imagery and photometry

Photometry (astronomy)

Photometry is a technique of astronomy concerned with measuring the flux, or intensity of an astronomical object's electromagnetic radiation...

 of naturally occurring and man-made emission phenomena such as airglow

Airglow

Airglow is the very weak emission of light by a planetary atmosphere. In the case of Earth's atmosphere, this optical phenomenon causes the night sky to never be completely dark .-Development:The airglow phenomenon was first identified in 1868 by Swedish scientist...

 and diffuse aurora. Secondary missions were to study interplanetary and interstellar objects (such as comets and stars) and to make atmospheric density measurements by stellar occultation

Occultation

An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. The word is used in astronomy . It can also refer to any situation wherein an object in the foreground blocks from view an object in the background...

s. The instrument consisted of two imaging cameras and a low-light-level TV camera mounted on the same base. Like CIRRIS, they were controlled from the flight deck. Dr. George R. Carruthers, then working for the United States Naval Research Laboratory

United States Naval Research Laboratory

The United States Naval Research Laboratory is the corporate research laboratory for the United States Navy and the United States Marine Corps and conducts a program of scientific research and development. NRL opened in 1923 at the instigation of Thomas Edison...

, was the PI for this experiment.

Uniformly Redundant Array

The Uniformly Redundant Array conducted a technology demonstration of coded aperture

Coded aperture

Coded Apertures or Coded-Aperture Masks are grids, gratings, or other patterns of materials opaque to various wavelengths of light. The wavelengths are usually high-energy radiation such as X-rays and gamma rays. By blocking and unblocking light in a known pattern, a coded "shadow" is cast upon a...

 imaging in space and the capability to form images without stabilization. The instrument was a wide field-of-view, photon-counting imaging device. Edward E. Fenimore of the Los Alamos National Laboratory

Los Alamos National Laboratory

Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...

 was PI for this experiment.

Gamma Ray Advanced Detector

GRAD was another technology demonstration program to test the suitability of bismuth germanate

Bismuth germanate

Bismuth germanium oxide is an inorganic chemical compound with main use as a scintillator. It forms cubic crystals....

 in gamma-ray detectors

Gamma spectroscopy

Gamma-ray spectroscopy is the quantitative study of the energy spectra of gamma-ray sources, both nuclear laboratory, geochemical, and astrophysical. Gamma rays are the highest-energy form of electromagnetic radiation, being physically exactly like all other forms except for higher photon energy...

, the suitability of n-type, high-purity germanium

Germanium

Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....

 gamma-ray detectors for space, the performance of an advanced gamma-ray spectrometer and to study the gamma ray background around the shuttle, as well as the gamma-ray spectrum of the sun and the Galactic Center

Galactic Center

The Galactic Center is the rotational center of the Milky Way galaxy. It is located at a distance of 8.33±0.35 kpc from the Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest...

. The instrument is non-steerable and is pointed by moving the Shuttle. Dr. C. Rester from the University of Florida

University of Florida

The University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...

 was the PI.

Horizon Ultraviolet Program

The Horizon Ultraviolet Program demonstrated the ability to measure the spatial and spectral characteristics of the Earth's horizon in the vacuum ultraviolet

Ultraviolet

Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 wavelength. The sensor was an Ebert-Fastie spectrometer

Spectrometer

A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization...

 telescope. F. S. Leblanc of the Phillips Laboratory was PI.

Quadrupole Ion Neutral Mass Spectrograph

The Quadrupole Ion Neutral Mass Spectrograph was designed to support the CIRRIS 1A experiment by providing positive ion and neutral contaminant species identifications, concentrations, and temporal variabilities. The sensor package was made up of an electron impact ion source, an ion-focusing grid system, a set of quadrupole rods

Quadrupole magnet

Quadrupole magnets consist of groups of four magnets laid out so that in the multipole expansion of the field the dipole terms cancel and where the lowest significant terms in the field equations are quadrupole. Quadrupole magnets are useful as they create a magnetic field whose magnitude grows...

, and an electron multiplier

Electron multiplier

An electron multiplier is a vacuum-tube structure that multiplies incident charges. In a process called secondary emission, a single electron can, when bombarded on secondary emissive material, induce emission of roughly 1 to 3 electrons...

. Dr. Edmond Tryczinski of Phillips Laboratory was the PI.