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Helfert, Michael R.

Publications and source records attributed to Helfert, Michael R..

18 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Interfacing remote sensing and geographic information systems for global environmental change research

Because changes in the Earth's environment have become major global issues, continuous, longterm scientific information is required to assess global problems such as deforestation, desertification, greenhouse effects and climate variations. Global change studies require understanding of interactions of complex processes regulating the Earth system. Space-based Earth observation is an essential element in global change research for documenting changes in Earth environment. It provides synoptic data for conceptual predictive modeling of future environmental change. This paper provides a brief overview of remote sensing technology from the perspective of global change research.

Lee, Jae K.↗
NASA NTRS1992

Earth observations during Space Shuttle mission STS-45 Mission to Planet Earth - March 24-April 2, 1992

A description is presented of the activities and results of the Space Shuttle mission STS-45, known as the Mission to Planet Earth. Observations of Mount St. Helens, Manila Bay and Mt. Pinatubo, the Great Salt Lake, the Aral Sea, and the Siberian cities of Troitsk and Kuybyshev are examined. The geological features and effects of human activity seen in photographs of these areas are pointed out.

Pitts, David E.↗
NASA NTRS1992

Earth observations on Space Shuttle Flight 43 - It was a dirty world

Attention is given to earth observations made by the crew of Space Shuttle Flight 43, during which atmospheric haze and its various aerosols were investigated. The length-of-record time series from the Space Shuttle Earth Observation Program was used to photograph some of the sites under active investigation. It was found that Lake Chad's northern basin remained dry, and the southern basin showed no appreciable changes in water level. The Okavango Swamp areas in Botswana showed agricultural burning at several sites, and increasing evidence of land use activity in the areas of the swamp that previously had been under natural cover. Consideration is also given to Hurricane Fefa and Tropical Storm Guillermo, the smoke from the Kuwaiti oil fires, Mount Pinatubo, dust storms in the Sahara, biomass burning, South Asian monsoon runoff, land use patterns, landforms and geology, and oceans and coastal features.

Amsbury, David L.↗
NASA NTRS1992

Ice patterns and hydrothermal plumes, Lake Baikal, Russia - Insights from Space Shuttle hand-held photography

Earth photography from the Space Shuttle is used to examine the ice cover on Lake Baikal and correlate the patterns of weakened and melting ice with known hydrothermal areas in the Siberian lake. Particular zones of melted and broken ice may be surface expressions of elevated heat flow in Lake Baikal. The possibility is explored that hydrothermal vents can introduce local convective upwelling and disrupt a stable water column to the extent that the melt zones which are observed in the lake's ice cover are produced. A heat flow map and photographs of the lake are overlaid to compare specific areas of thinned or broken ice with the hot spots. The regions of known hydrothermal activity and high heat flow correlate extremely well with circular regions of thinned ice, and zones of broken and recrystallized ice. Local and regional climate data and other sources of warm water, such as river inlets, are considered.

Evans, Cynthia A.↗
NASA NTRS1991

Earth observations during Space Shuttle flight STS-35 - Columbia's Mission to Planet Earth, December 2-10, 1990

Some of the most significant earth-viewing imagery obtained during Space Shuttle Columbia's flight STS-35, December 2-10, 1990, is reviewed with emphasis on observations of the Southern Hemisphere. In particular, attention is given to environmental observations in areas of Madagascar, Brazil, and Persian Gulf; observation of land resources (Namibia, offshore Australia); and observations of ocean islands (Phillipines, Indonesia, and Reunion). Some of the photographs are included.

Lulla, Kamlesh P.↗
NASA NTRS1991

Earth observations during Space Shuttle flight STS-31: The earth from 600 km - April 24 through 29, 1990

Images taken aboard the Space Shuttle flight STS-31 are presented and discussed in terms of documenting key features and describing regional interrelationships. The images comprise regional views and continuous swath maps that are intended to serve as linkage and/or context for related photographs in the shuttle database. The Linhof hand-held mapping camera is employed at 20-s intervals resulting in contiguous swaths with 75-percent overlap, and Hasselblad images are taken simultaneously to complement the swaths. Specific examples of the products are given for regions including Lake Eyre, Australia, Madagascar, and Central America; specific landforms are also shown including the El Chichon volcano, and an example is shown of the differential heating of land and water. The photographs are considered useful for mapping large-scale features and for providing context for smaller image-data products.

Evans, Cynthia A.↗
NASA NTRS1991

Smoke palls induced by Kuwaiti oilfield fires mapped from Space Shuttle imagery

Consideration is given to initial observations on the Kuwaiti oilfield fires and the spatial and areal extent of these smoke palls as viewed from the Space Shuttle flights during April/May 1991. It is concluded that one of the early lessons learned from Kuwaiti oilfield fires is that the presence of intelligent observers on orbit is of great value for acquiring data and confirm/deny events.

Lulla, Kamlesh P.↗
NASA NTRS1991

Earth observations during Space Shuttle flight STS-41 - Discovery's mission to planet earth

An overview of space flight STS-41 is presented, including personal observations and comments by the mission astronauts. The crew deployed the Ulysses spacecraft to study the polar regions of the sun and the interplanetary space above the poles. Environmental observations, including those of Lake Turkana, Lake Chad, biomass burning in Madagascar and Argentina, and circular features in Yucatan are described. Observations that include landforms and geology, continental sedimentation, desert landscapes, and river morphology are discussed.

Lulla, Kamlesh P.↗
NASA NTRS1990

Earth observations during Space Shuttle Mission STS-33 - November 23-27, 1989

An overview is presented of photographs, astronaut impressions, and photographic equipment and techniques coincident with the Discovery STS-33 mission of November 23-27, 1989. Particularly significant geographical photographs of southern Africa, Madagascar, northern Africa, Southeast Asia islands, Pacific islands, and Australia are shown and reviewed. Meteorological and oceanographic observations are summarized along with film anomalies that occurred during this mission.

Amsbury, David L.↗
NASA NTRS1990

Mapping continental-scale biomass burning and smoke palls over the Amazon basin as observed from the Space Shuttle

Space Shuttle and Skylab-3 photography has been used to map the areal extent of Amazonian smoke palls associated with biomass burning (1973-1988). Areas covered with smoke have increased from approximately 300,000 sq km in 1973 to continental-size smoke palls measuring approximately 3,000,000 sq km in 1985 and 1988. Mapping of these smoke palls has been accomplished using space photography mainly acquired during Space Shuttle missions. Astronaut observations of such dynamic and vital environmental phenomena indicate the possibility of integrating the earth observation capabilities of all space platforms in future Global Change research.

Helfert, Michael R.↗
NASA NTRS1990

Earth observations during Space Shuttle mission STS-34 - 18-23 October 1989

An overview is presented of the 31st Space Shuttle mission, whose major objective was to deploy the Galileo spacecraft. Color images are presented of photos taken by the four videocameras in the payload bay, one 16-mm Arriflex in the cabin, a videocamcorder, three 35 mm cameras, two 70 mm cameras, and an IMAX camera. In addition, descriptions of visual observations by the mission astronauts are given. The most significant STS-34 earth photography for the major geographical regions is discussed. Individual highlights of this mission include observation of the apparent recovery of the water level of Lake Nasser to conditions similar to those during the second Space Shuttle mission of 1981; the documentation of the impact of the Yucatan forest blowdown and fires after the passage of Hurricane Gilbert; and the confirmation of the high value of space photography under low and very low sun angle conditions for geomorphological and geological analyses.

Helfert, Michael R.↗
NASA NTRS1990

Earth observations during Space Shuttle mission STS-30

The earth observations that were conducted during the STS-30 mission in May, 1989 are examined. An overview of the STS-30 mission is given, noting the launch of the Magellan spacecraft. The major positions of STS-30 photographs are illustrated and the sun elevation angles of the photographs and the types of films used during the mission are listed. Photographs of various regions are described, focusing on North Africa and the Middle East, South and Southeast Asia, Central America, the Caribbean, and the Southern U.S. The use of the photographs for various research purposes is discussed, including oceanography, meteorology, and polarization experiments. Also, consideration is given to the use of video/camcorders for earth observations.

Helfert, Michael R.↗
NASA NTRS1989

Earth observations during Space Shuttle flight STS-27: A high latitude observations opportunity - 2-6 December 1988

The earth observations from the STS-27 mission on December 2-6, 1988 are reported. The film and generic scene characteristics chosen for the mission are given. Results are given from geological observations of the Ruwenzori Mountains between Uganda and Zaire, four rift valley systems in Africa and Asia, and several volcanoes and impact craters. Environmental observations of Africa, the Middle East, South Asia, North America and the Soviet Union, are presented. Also, meteorological and oceanographic observations are discussed. The uniqueness of the high-inclination winter launch of the STS-27 mission for obtaining observations of specific features is noted.

Whitehead, Victor S.↗
NASA NTRS1989

The NASA Space Shuttle Earth Observations Office

The NASA Space Shuttle Earth Observations Office conducts astronaut training in earth observations, provides orbital documentation for acquisition of data and catalogs, and analyzes the astronaut handheld photography upon the return of Space Shuttle missions. This paper provides backgrounds on these functions and outlines the data constraints, organization, formats, and modes of access within the public domain.

Helfert, Michael R.↗
NASA NTRS1989

Monitoring tropical environments with Space Shuttle photography

Orbital photography from the Space Shuttle missions (1981-88) and earlier manned spaceflight programs (1962-1975) allows remote sensing time series to be constructed for observations of environmental change in selected portions of the global tropics. Particular topics and regions include deforestation, soil erosion, supersedimentation in streams, lacustrine, and estuarine environments, and desertification in the greater Amazon, tropical Africa and Madagascar, South and Southeast Asia, and the Indo-Pacific archipelagoes.

Helfert, Michael R.↗
NASA NTRS1989

Analysis of seasonal characteristics of Sambhar Salt Lake, India, from digitized Space Shuttle photography

Sambhar Salt Lake is the largest salt lake (230 sq km) in India, situated in the northwest near Jaipur. Analysis of Space Shuttle photographs of this ephemeral lake reveals that water levels and lake basin land-use information can be extracted by both the digital and manual analysis techniques. Seasonal characteristics captured by the two Shuttle photos used in this study show that additional land use/cover categories can be mapped from the dry season photos. This additional information is essential for precise cartographic updates, and provides seasonal hydrologic profiles and inputs for potential mesoscale climate modeling. This paper extends the digitization and mensuration techniques originally developed for space photography and applied to other regions (e.g., Lake Chad, Africa, and Great Salt Lake, USA).

Lulla, Kamlesh P.↗
NASA NTRS1989

The decrease of Lake Chad as documented during twenty years of manned space flight

Space photography has been successfully used to extend the space remote sensing data base for environmental monitoring by a decade. In this study of Lake Chad, space photographs were digitized and registered to a topographic base map before water classifications were performed. From 1966 to 1985 over a 21,000-square-kilometer decrease in lake surface area was observed.

Mohler, Robert R. J.↗