Engineering topics

Denn, Fred M.

Publications and source records attributed to Denn, Fred M..

5 records

NASA NTRS1995

ATLAS-3 correlative measurement opportunities with UARS and surface observations

The third ATmospheric Laboratory for Applications and Science (ATLAS-3) mission was flown aboard the Space Shuttle launched on November 3, 1994. The mission length was approximately 10 days and 22 hours. The ATLAS-3 Earth-viewing instruments provided a large number of measurements which were nearly coincident with observations from experiments on the Upper Atmosphere Research Satellite (UARS). Based on ATLAS-3 instrument operating schedules, simulations were performed to determine when and where correlative measurements occurred between ATLAS and UARS instruments, and between ATLAS and surface observations. Results of these orbital and instrument simulations provide valuable information for scientists to compare measurements between various instruments on the two satellites and at selected surface sites.

Harrison, Edwin F.↗

NASA NTRS1993

ATLAS-2 and UARS correlative measurement opportunities during Space Shuttle mission on April 8-17, 1993

The second ATmospheric Laboratory for Applications and Science (ATLAS-2) mission was flown aboard the Space Shuttle Discovery from 8-17 Apr. 1993. The nighttime launch at 0529 Greenwich Mean Time provided maximum solar occultation sunrise coverage of the northern latitudes by the Atmospheric Trace Molecule Spectroscopy instrument. The ATLAS-2 Earth-viewing instruments provided a large number of measurements which were nearly coincident with observations from experiments on the Upper Atmosphere Research Satellite (UARS). Based on instrument operating schedules during the ATLAS-2 mission, simulations were performed to determine when and where correlative measurements between ATLAS and UARS instruments occurred. Results of these orbital and instrument simulations provide valuable information for the ATLAS and UARS scientists to compare measurements between various instruments on the two satellites.

Harrison, Edwin F.↗

NASA NTRS1992

Correlative measurement opportunities between ATLAS-1 and UARS experiments

The first ATmospheric Laboratory for Applications and Science (ATLAS-1) mission was flown aboard the Space Shuttle from March 24 to April 2, 1992. The ATLAS-1 instruments provided a large number of measurements which were coincident with observations from experiments on the Upper Atmosphere Research Satellite (UARS). During the ATLAS-1 mission, simulations were performed to predict when and where coincident measurements between ATLAS and UARS instruments would occur. These predictions were used to develop instrument operation schedules to maximize the correlative opportunities between the two satellites. Results of the simulations provide valuable information for the ATLAS and UARS scientists to compare measurements between various instruments on the two satellites.

Harrison, Edwin F.↗

NASA NTRS1992

Orbital analysis and instrument viewing considerations for the Earth Observing System (EOS) satellite

An orbital analysis was performed to evaluate the effects of orbit altitude and equatorial crossing time on meeting the scientific requirements for the various experiments on the Earth Observing System (EOS) satellite. Results show that a 705-km orbit is more advantageous than an 824-km orbit for EOS. The lower orbit has higher spatial resolution and provides global coverage in a shorter period of time with a reasonable scan angle than the 824-km orbit. Both late-morning and early-afternoon equatorial crossing times offer certain advantages depending on the specific EOS science objective. Multiple satellites with equatorial crossing times spaced throughout the day are required to study diurnal variations of clouds, winds, and radiative parameters.

Harrison, Edwin F.↗

NASA NTRS1988

Estimation of surface insolation using sun-synchronous satellite data

A technique is presented for estimating insolation at the earth's surface using only sun-synchronous satellite data. The technique was tested by comparing the insolation results from year-long satellite data sets with simultaneous ground-measured insolation taken at five continental United States sites. Monthly average insolation values derived from the satellite data showed a standard error of 4.2 W/sq m, or 2.7 percent of the average ground insolation value.

Darnell, Wayne L.↗