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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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

The Great White Ocean

Satellite data have revealed overall decreases in the Arctic sea ice cover since the late 1970s, although with substantial interannual variability. The ice reductions are likely tied to an overall warming in the Arctic region over the same time period, although both the warming and the ice reductions could be connected to large-scale oscillations within the system. Should the ice reductions continue, consequences to the Arctic ecosystems and climate could be considerable.

Parkinson, Claire L.↗
NASA NTRS2005

About an Element of Human Greatness

One of the things Dr. von Braun instinctively knew was that it was as nearly important to explain why we should go into space as to build the machines to take us there. He wrote books and magazine articles, spoke to everyone he could formally and informally, and spent his life to his dying day seeking to educate everyone on the importance of and need for spaceflight. Why should we go? I think there are actually two principle reasons: 1) Because the solar system is filled with cheap, clean energy, and we need to go get it, and, 2) this one may well be even more important, because we need a purpose for ourselves and our country. I think we need an eternal frontier to push up against, our purpose to conquer and settle it. The nice thing about doing that is the solar system is a very rich place, filled with not only mineral wealth but energy, a nearly inexhaustible supply. And if there s one thing this country and this planet desperately needs and is willing to pay for now and forever is energy. The solar system is where it is. We've got to go after it. I believe, then, that Americans have both a self-interest and a patriotic duty to convince ourselves it is time to take another giant step into space. The way to do that is to do what Dr. von Braun did, cut metal and start flying. Success engenders success. Dr. von Braun s grand dream need never die. NASA can spark a twenty-first-century revolution in transportation and energy that could fundamentally change the way we fly through space, power the world, even care for the sick if we do it right. All those things require cheap and clean energy. It exists in the solar system in a variety of forms. Solar energy is the most obvious form, but there are others, including helium-3, which may be the perfect fuel for fusion reactors, and also just happens to cover the Moon. I believe we must go after it. We just need to believe in ourselves and our purpose. I call on all of you here today to join together, get things moving again, and get serious about conquering space. If we do, we'll assure the country s prosperity, and the world s survival, too, for centuries. Along the way, maybe we ll finally understand why my old preacher thought St. Peter s comment about looking for new heavens was so important. According to His promise, it s a big challenge, a huge responsibility, to try to fulfill such a promise and prophecy.

Hickam, Homer↗
NASA NTRS2003

Greatly enhanced deep space mission data return using verv large DSN arrays

The purposes of the Array System are: To fulfill the mission needs for higher data rates in the post-2010 era - Reduce the cost per data bit by two orders of magnitude. Specific Goal: Achieve a factor of 10 increase in DSN reception capability per decade from 2012 through 2027 (an average of 1 dB per year).

array↗
NASA NTRS2006

Aerosol Indirect Effect Studies at Southern Great Plains During the May 2003 Intensive Operations Period

During May 2003 the Department of Energy's Atmospheric Radiation Measurement Program conducted an Intensive Operations Period (IOP) to measure the radiative effects of aerosol and clouds. A suite of both in situ and remote sensing measurements were available to measure aerosol and cloud parameters. This paper has three main goals: First, it focuses on comparison between in situ retrievals of the radiatively important drop effective radius r(sub e) and various satellite, airborne, and surface remote sensing retrievals of the same parameter. On 17 May 2003, there was a fortuitous, near-simultaneous sampling of a stratus cloud by five different methods. The retrievals of r(sub e) agree with one another to within approx.20%, which is approximately the error estimate for most methods. Second, a methodology for deriving a best estimate of r(sub e) from these different instruments, with their different physical properties and sampling volumes, is proposed and applied to the 17 May event. Third, the paper examines the response of r(sub e) to changes in aerosol on 3 days during the experiment and examines the consistency of remote sensing and in situ measurements of the effect of aerosol on r(sub e). It is shown that in spite of the generally good agreement in derived r(sub e), the magnitude of the response of r(sub e), to changes in aerosol is quite sensitive to the method of retrieving r(sub e) and to the aerosol proxy for cloud condensation nuclei. Nonphysical responses are sometimes noted, and it is suggested that further work needs to be done to refine these techniques.

Feingold, Graham↗
NASA NTRS2008

Ares I-X Overview - The First Chapter in the Next Great Adventure

Ares I-X is the first flight of NASA's new Constellation Program. Ares I-X is a development test flight to provide engineering data to inform the design of the Ares I prior to CDR. Ares I will replace the Space Shuttle which is scheduled for 2010 retirement . Ares I-X is an uncrewed, sub-orbital development flight test . Ares I-X will provide opportunity to test ground facilities and operations at NASA's Kennedy Space Center. Ares I-X is on track for May 2009 launch date. Objectives include: (1) Demonstrate control of a dynamically similar, integrated Ares I/Orion, using Ares I relevant ascent control algorithms; (2) Perform an in-flight separation/staging event between a Ares I-similar First Stage and a representative Upper Stage; (3) Demonstrate assembly and recovery of a new Ares I-like First Stage element at KSC; (4) Demonstrate First Stage separation sequencing, and quantify First Stage atmospheric entry dynamics, and parachute performance; and (5) Characterize magnitude of integrated vehicle roll torque throughout First Stage flight.

Leahy, Bart↗