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Heath, D.

Publications and source records attributed to Heath, D..

Status of the Geostationary Spectrograph (GeoSpec) for Earth and Atmospheric Science Applications

GeoSpec will support future satellite mission concepts in the Atmospheric Sciences and in Land and Ocean Sciences by providing time-resolved measurements of both chemically linked atmospheric trace gas concentrations of important molecules such as O3, NO2, CH2O and SO2 and at the same time coastal and ocean pollution events, tidal effects, and the origin and evolution of aerosol plumes. The instrument design concept in development is a dual spectrograph covering the WMS wavelength region of 310-500 nm and the VIS/NIR wavelength region of 480-900 nm coupled to all reflective telescope and high sensitivity PIN/CMOS area detector. The goal of the project is to demonstrate a system capable of making moderate spatial resolution (750 meters at nadir) hyperspectral measurements (0.6 to 1.2 nm resolution) from a geostationary orbit. This would enable studies of time-varying pollution and coastal change processes with a temporal resolution of 5 minutes on a regional scale to 1 hour on a continental scale. Other spatial resolutions can be supported by varying the focal length of the input telescope. Scientific rationale and instrument design and status will be presented.

Janz, Scott

Oxygen species

The spatial distribution of ozone, as predicted by numerical models, is compared with observations. A set of reference ozone profiles was developed against which to compare current numerical calculations. Most of the analyses will focus on ozone between 30 and 70 km altitude.

Brasseur, G.

Twilight ozone measurement by solar occultation from AE 5

The BUV on AE 5 was used for a solar occultation measurement of atmospheric ozone. An observation was carried out during the morning twilight near 5 deg N, December 17, 1976, at the fixed wavelength of 255.5 nm, and a profile between 49 and 82 km was obtained. The number densities determined by this measurement were 3.7 x 10 to the 10th cu cm at 50 km, 5.1 x 10 to the 9th at 60 km, 3.9 x 10 to the 8th at 70 km, and 3.0 x 10 to the 7th at 80 km. No evidence of a high altitude secondary maximum was found. These concentrations are between a factor of 4 and 20 smaller than those midnight results reported from a Copernicus measurement, and similar to the values from the Krueger-Minzer Mid-latitude Model above 55 km. These values may be as much as a factor of 2 less than the Krueger-Minzer model below 50.

Guenther, B.

OFT-1 reference flight profile. Deorbit through landing

Changes made in the de-orbiting through landing reference flight profile because of increases in Orbiter weight during entry and in the circular orbital attitude prior to deorbit are discussed. The rationale for the shaping of each phase is also presented.

Heath, D.

Long duration solar active regions

Nimbus 3 and 4 observations of ultraviolet active regions of the sun have been investigated. It is not clear what is producing these UV-active regions, however, it could be changes in the overall intensity of the solar continuum near the region of the temperature minimum, or the solar flux variations that have been seen could be due to a continuous type of absorption like that associated with the ionization limits of elements such as aluminum, silicon, or magnesium.

Heath, D.