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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 199 records · Page 11
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NASA NTRS1996

Radar Reconnaissance of Near-Earth Objects at the Dawn of the Next Millenium

From Intro.: Radar, the most powerful groundbased technique for post-discovery investigation of NEOs, can contribute a great deal to their exploration as well as to identification and mitigation of hazardous objects. My intentions in this article are to review the current state of NEO radar reconnaissance, examine the imminent prospects for this work as upgraded instrumentation becomes available, and propose construction of a next-generation radar telescope that, unlike any existing radar instrument, would be optimized for, and dedicated to, NEO radar.

radar near-Earth objects NEO NEO radar↗
NASA NTRS2006

Dawn of a New Space Age: Developing a Global Exploration Strategy.

Jeff Volosin is an aerospace engineer with over 20 years of experience in the design, development, and operations of both robotic and crewed spacecraft. Mr. Volosin is currently leading the NASA effort to develop and integrate a global exploration strategy which reflects the lunar exploration interests of international space agencies, academia and commercial stakeholders. Prior to joining NASA as a member of the Exploration Systems Mission Directorate in 2004, Jeff was an aerospace contractor, serving in a number of leadership positions including: Operations Manager for the NASA Communications Network and Flight Operations Manager for the Advanced Composition Explorer, Tropical Rainfall Measuring Mission, and the NOAA Polar and Geostationary satellite constellations. Earlier in his career, Jeff spent 4 years as a system engineer supporting the Space Exploration Initiative studies on human voyages to the Moon and Mars and also supported the Space Station program as an advanced life support engineer.

Volosin, Jeff↗
NASA NTRS2006

IIP Update: A Packaged Coherent Doppler Wind Lidar Transceiver. Doppler Aerosol WiNd Lidar (DAWN)

The state-of-the-art 2-micron coherent Doppler wind lidar breadboard at NASA/LaRC will be engineered and compactly packaged consistent with future aircraft flights. The packaged transceiver will be integrated into a coherent Doppler wind lidar system test bed at LaRC. Atmospheric wind measurements will be made to validate the packaged technology. This will greatly advance the coherent part of the hybrid Doppler wind lidar solution to the need for global tropospheric wind measurements.

Kavaya, Michael J.↗
NASA NTRS2006

Compact, Engineered, 2-Micron Coherent Doppler Wind Lidar Prototype for Field and Airborne Validation: Doppler Aerosol WiNd Lidar (DAWN). Interim Review #1 (6 months)

A new project, selected in 2005 by NASA's Science Mission Directorate (SMD), under the Instrument Incubator Program (IIP), will be described. The 3-year effort is intended to design, fabricate, and demonstrate a packaged, rugged, compact, space-qualifiable coherent Doppler wind lidar (DWL) transceiver capable of future validation in an aircraft and/or Unmanned Aerial Vehicle (UAV). The state-of-the-art 2-micron coherent DWL breadboard at NASA/LaRC will be engineered and compactly packaged consistent with future aircraft flights. The packaged transceiver will be integrated into a coherent DWL system test bed at LaRC. Atmospheric wind measurements will be made to validate the packaged technology. This will greatly advance the coherent part of the hybrid DWL solution to the need for global tropospheric wind measurements.

Kavaya, Michael J.↗
NASA NTRS2011

DAWN Coherent Wind Profiling Lidar Flights on NASA's DC-8 During GRIP

Almost from their invention, lasers have been used to measure the velocity of wind and objects; over distances of cm to 10s of km. Long distance (remote) sensing of wind has been accomplished with continuous-wave (CW), focused pulsed, and collimated pulsed lasers; with direct and coherent (heterodyne) optical detection; and with a multitude of laser wavelengths. Airborne measurement of wind with pulsed, coherent-detection lidar was first performed in 1971 with a CW CO2 laser1, in 1972 with a pulsed CO2 laser2, in 1993 with a pulsed 2-micron laser3, and in 1999 with a pulsed CO2 laser and nadir-centered conical scanning4. Of course there were many other firsts and many other groups doing lidar wind remote sensing with coherent and direct detection. A very large FOM coherent wind lidar has been built by LaRC and flown on a DC-8. However a burn on the telescope secondary mirror prevented the full demonstration of high FOM. Both the GRIP science product and the technology and technique demonstration from aircraft are important to NASA. The technology and technique demonstrations contribute to our readiness for the 3D Winds space mission. The data analysis is beginning and we hope to present results at the conference.

Kavaya, Michael J.↗
NASA NTRS2012

Do Mesosiderites Reside on 4 VESTA? an Assessment Based on Dawn Grand Data

Almost a century ago, simple petrographic observations were used to suggest a close genetic link between eucrites and the silicates in mesosiderites [1]. Mesosiderites are composed of roughly equal proportions of silicates that are very similar in mineralogy and texture to howardites, and Fe, Ni metal (Fig. 1) [2]. This similarity has led some to conclude that mesosiderites come from the howardite, eucrite and diogenite (HED) parent asteroid [3, 4]. Subsequent petrologic study demonstrated a number of differences between mesosiderite silicates and HEDs that are more plausibly explained as requiring separate parent asteroids [5]. However, HEDs and mesosiderites are identical in oxygen isotopic composition, and this has been used to argue for a common parent 4 Vesta [6].

Mittlefehldt, D. W.↗
NASA NTRS2016

Communicating with Light: A New Dawn in the Information Age

You and I are living in a very special time; the age of Solar System exploration. Our Solar System is a complex masterpiece of which we knew so little from our ground-based observations. But within the span of a single lifetime, NASA has sent spacecraft to every planet and several moons, our first eyes to set upon undiscovered lands. Before we endeavored on this journey everything we knew of Pluto could have fit on a single file card, and now we downlink new data every day.

Optical Communications↗