The Science Of The Viking Missions

The NASA\u27s next missions to Mars are to land two unmanned spacecraft on the surface in 1976 to perform scientific experiments. This pair of missions called Viking consists of two identical spacecraft each launched from a Titan/Centaur in the summer of 1975- Each spacecraft consists of a Lander and an Orbiter combination and together carry 13 scientific investigations. The Orbiter carries its Lander to the planet and then acts as a relay to return the telemetered data to Earth. Following the launches in the summer of 1975\u3e there is an 11-month cruise to the planet. The spacecraft are injected into highly elliptical synchronous orbits about the planet. The periapsis of about 1500 km is selected to be over the appropriate preselected landing site. The missions are separated by about 2 months so that the missions can be handled consecutively. For each spacecraft, after the landing site is certified and the orbit is trimmed, the Lander is released. The nominal landing target is an ellipse about 100 by 500 km. The Lander enters the Martian atmosphere at about 15° traveling about 5 km/sec. The initial deceleration is from the aerodynamic drag of its 12-foot aeroshell. At about 5 km above the surface, a parachute is deployed as the second braking system. At 2 km as sensed by an onboard radar, three retrorockets are fired and the Lander is soft landed onto the surface (see Fig. 1). The scientific experiments aboard the Lander require several months of operation; the nominal length of the mission is 60 days. Power for this period on the Lander is obtained from two 35-watt radioisotope thermoelectric generators. The data from the experiments are telemetered by relay up to the Orbiter and back to Earth or may be telemetered directly from the.Lander to the Earth at a lower rate. Commands to both the Lander and Orbiter will be sent over the deep space net. A tape recorder aboard the Lander will allow storage of data for subsequent transmission, thereby permitting events to be recorded independent of the positions of the Orbiter or Earth

The 1989 NASA-ASEE Summer Faculty Fellowship Program in Aeronautics and Research

The 1989 NASA-ASEE Summer Faculty Fellowship Program at the Goddard Space Flight Center was conducted during 5 Jun. 1989 to 11 Aug. 1989. The research projects were previously assigned. Work summaries are presented for the following topics: optical properties data base; particle acceleration; satellite imagery; telemetry workstation; spectroscopy; image processing; stellar spectra; optical radar; robotics; atmospheric composition; semiconductors computer networks; remote sensing; software engineering; solar flares; and glaciers

COBE's search for structure in the Big Bang

The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle

Research and Technology Report. Goddard Space Flight Center

This issue of Goddard Space Flight Center's annual report highlights the importance of mission operations and data systems covering mission planning and operations; TDRSS, positioning systems, and orbit determination; ground system and networks, hardware and software; data processing and analysis; and World Wide Web use. The report also includes flight projects, space sciences, Earth system science, and engineering and materials

The 1991 research and technology report, Goddard Space Flight Center

The 1991 Research and Technology Report for Goddard Space Flight Center is presented. Research covered areas such as (1) earth sciences including upper atmosphere, lower atmosphere, oceans, hydrology, and global studies; (2) space sciences including solar studies, planetary studies, Astro-1, gamma ray investigations, and astrophysics; (3) flight projects; (4) engineering including robotics, mechanical engineering, electronics, imaging and optics, thermal and cryogenic studies, and balloons; and (5) ground systems, networks, and communications including data and networks, TDRSS, mission planning and scheduling, and software development and test

Research & Technology Report Goddard Space Flight Center

The main theme of this edition of the annual Research and Technology Report is Mission Operations and Data Systems. Shifting from centralized to distributed mission operations, and from human interactive operations to highly automated operations is reported. The following aspects are addressed: Mission planning and operations; TDRSS, Positioning Systems, and orbit determination; hardware and software associated with Ground System and Networks; data processing and analysis; and World Wide Web. Flight projects are described along with the achievements in space sciences and earth sciences. Spacecraft subsystems, cryogenic developments, and new tools and capabilities are also discussed

The 1994 research and technology report at the Goddard Space Flight Center

The breadth of subject material in this 1994 edition of the Research and Technology Report illustrates the broad scope of activities at the Goddard Space Flight Center. The numerous entries dealing with data processing and visualization show the strong emphasis on data and its interpretation. Reports are presented in the following sections: data processing and visualization; space sciences - high energy astronomy, solar system, and new techniques; earth system science - atmospheres, oceans and ice, solid earth, and soils and vegetation; networks, planning, and information systems - mission scheduling and operations, spacecraft operation and status, software engineering, and infrastructure support; engineering and materials - spacecraft subsystems, launch vehicles, thermal control, new mechanisms, and testing and evaluation; and flight projects

R and T report: Goddard Space Flight Center

The 1993 Research and Technology Report for Goddard Space Flight Center is presented. Research covered areas such as (1) flight projects; (2) space sciences including cosmology, high energy, stars and galaxies, and the solar system; (3) earth sciences including process modeling, hydrology/cryology, atmospheres, biosphere, and solid earth; (4) networks, planning, and information systems including support for mission operations, data distribution, advanced software and systems engineering, and planning/scheduling; and (5) engineering and materials including spacecraft systems, material and testing, optics and photonics and robotics

Biological Life Support Technologies: Commercial Opportunities

The papers from the workshop on Biological Life Support Technologies: Commercial Opportunities are presented. The meeting attracted researchers in environmental and bioregenerative systems. The role of biological support technologies was evaluated in the context of the global environmental challenge on Earth and the space exploration initiative, with its goal of a permanent space station, lunar base, and Mars exploration