| Conditions of Passage and Entrapment of Terrestrial Planets in Spin-Orbit Resonances |
10 Jun 2012 |
9 pages |
| Authors:
Valeri V Makarov; NAVAL OBSERVATORY WASHINGTON DC
|
 | The dynamical evolution of terrestrial planets resembling Mercury in the vicinity of spin-orbit resonances is investigated using comprehensive harmonic expansions of the tidal torque taking into account the frequency dependent quality factors and Love numbers. The torque equations are integrated numerically with a small step in time, including the oscillating triaxial torque components but neglecting the layered structure of the planet and assuming a zero obliquity. We find that a ... |
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| Insanity: Four Decades of U.S. Counterdrug Strategy |
01 Apr 2012 |
75 pages |
| Authors:
Michael F Walther; ARMY WAR COLL CARLISLE BARRACKS PA
|
| In the four decades since President Nixon first declared war on drugs the U.S. counterdrug strategy has remained virtually unchanged favoring supply-reduction, law enforcement and criminal sanctions over demand-reduction, treatment and education. While the annual counterdrug budget has ballooned from $100 million to $25 billion, drug availability of most illicit drugs remains at an all-time high. The human cost is staggering nearly 40,000 drug-related deaths in the U.S. annually. The ... |
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| Tidal Dissipation Compared To Seismic Dissipation: In Small Bodies, Earths, And Super-Earths |
20 Feb 2012 |
22 pages |
| Authors:
Michael Efroimsky; NAVAL OBSERVATORY WASHINGTON DC
|
| While the seismic quality factor and phase lag are defined solely by the bulk properties of the mantle, their tidal counterparts are determined by both the bulk properties and the size effect (self-gravitation of a body as a whole). For a qualitative estimate, we model the body with a homogeneous sphere, and express the tidal phase lag through the lag in a sample of material. Although simplistic, our model is ... |
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| Precision Astrometry of the Exoplanet Host Candidate GD 66 |
Jan 2012 |
6 pages |
| Authors:
J Farihi; J P Subasavage; E P Nelan; H C Harris; C C Dahn; J Nordhaus; D S Spiegel; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The potential existence of a giant planet orbiting within a few au of a stellar remnant has profound implications for both the survival and possible regeneration of planets during post-main-sequence stellar evolution. This paper reports Hubble Space Telescope Fine Guidance Sensor and US Naval Observatory relative astrometry of GD66, a white dwarf thought to harbour a giant planet between 2 and 3 au based on stellar pulsation arrival times. Combined ... |
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| Know the Star, Know the Planet. 2. Speckle Interferometry of Exoplanet Host Stars |
Nov 2011 |
7 pages |
| Authors:
Brian D Mason; William I Hartkopf; Deepak Raghavan; John P Subasavage; Jr Roberts Lewis C; Nils H Turner; Theo A ten Brummelaar; NAVAL OBSERVATORY WASHINGTON DC
|
| A study of the host stars to exoplanets is important for understanding their environment. To that end, we report new speckle observations of a sample of exoplanet host primaries. The bright exoplanet host HD 8673 (= HIP 6702) is revealed to have a companion, although at this time we cannot definitively establish the companion as physical or optical. The observing lists for planet searches and for these observations have for ... |
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| Know the Star, Know the Planet |
Nov 2011 |
8 pages |
| Authors:
Jr Roberts Lewis C; Nils H Turner; Theo A ten Brummelaar; Brian D Mason; William I Hartkopf; NAVAL OBSERVATORY WASHINGTON DC
|
| The results of an adaptive optics survey of exoplanet host stars for stellar companions are presented. We used the Advanced Electro-Optical System telescope and its adaptive optics system to collect deep images of the stars in the I band. Sixty-two exoplanet host stars were observed and fifteen multiple star systems were resolved. Of these eight are known multiples, while seven are new candidate binaries. For all binaries, we measured the ... |
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| Molecular and Dusty Layers of Asymptotic Giant Branch Stars Studied with the VLT Interferometer |
Sep 2011 |
6 pages |
| Authors:
Markus Wittkowski; Iva Karovicova; David A Boboltz; Eric Fossat; Michael Ireland; Keiichi Ohnaka; Michael Scholz; Francois van Wyk; Patricia Whitelock; Peter R Wood; Albert A Zijlstra; NAVAL OBSERVATORY WASHINGTON DC
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| Mass loss from asymptotic giant branch (AGB) stars is the most important driver for the evolution of low to intermediate mass stars towards planetary nebulae. It is also one of the most important sources of chemical enrichment of the interstellar medium. The mass-loss process originates in the extended atmosphere, whose structure is affected by stellar pulsations, and where molecular and dusty layers are formed. Optical interferometry resolves the extended atmospheres ... |
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| Characteristics of Kepler Planetary Candidates Based on the First Data Set |
20 Feb 2011 |
21 pages |
| Authors:
William J Borucki; David G Koch; Gibor Basri; Natalie Batalha; Alan Boss; Timothy M Brown; Douglas Caldwell; Joergen Christensen-Dalsgaard; William D Cochran; Edna DeVore; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| In the spring of 2009, the Kepler Mission commenced high-precision photometry on nearly 156,000 stars to determine the frequency and characteristics of small exoplanets, conduct a guest observer program, and obtain asteroseismic data on a wide variety of stars. On 2010 June 15, the Kepler Mission released most of the data from the first quarter of observations. At the time of this data release, 705 stars from this first data ... |
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| Modeling Kepler Transit Light Curves as False Positives: Rejection of Blend Scenarios for Kepler-9, and Validation of Kepler-9 d, a Super-Earth-Size Planet in a Multiple System |
20 Jan 2011 |
20 pages |
| Authors:
Guillermo Torres; Francois Fressin; Natalie M Batalha; William J Borucki; Timothy M Brown; Stephen T Bryson; Lars A Buchhave; David Charbonneau; David R Ciardi; Edward W Dunham; CALIFORNIA INST OF TECHNOLOGY PASADENA CA JET PROPULSION LAB
|
| Light curves from the Kepler Mission contain valuable information on the nature of the phenomena producing the transit-like signals. To assist in exploring the possibility that they are due to an astrophysical false positive we describe a procedure (BLENDER) to model the photometry in terms of a blend rather than a planet orbiting a star. A blend may consist of a background or foreground eclipsing binary (or star-planet pair) whose ... |
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| A New Astrometric Reduction of Photographic Plates Using the DAMIAN Digitizer: Improving the Dynamics of the Jovian System |
2011 |
9 pages |
| Authors:
V. Robert; J. De Cuyper; J. Arlot; G. de Decker; J. Guibert; V. Lainey; D. Pascu; L. Winter; N. Zacharias; NAVAL OBSERVATORY WASHINGTON DC
|
| The astrometric monitoring of the natural planetary satellites is an important step to assess the formation and the evolution of these systems. However, in order to quantify relevant gravitational effects such as tidal forces, it is necessary to have very accurate observations over a long time interval. Unfortunately, the accuracy is decreasing as one considers older observations. To solve this issue, digitizing of old photographic plates is an attractive method, ... |
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| Radio Observations of HD 80606 Near Planetary Periastron |
DEC 2010 |
7 pages |
| Authors:
T. J. Lazio; P. D. Shankland; W. M. Farrell; D. L. Blank; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| This paper reports Very Large Array observations at 325 and 1425 MHz (lambda 90 cm and lambda 20 cm) during and near the periastron passage of HD 80606b on HJD 2454424.86 (2007 November 20). We obtain flux density limits (3 sigma) of 1.7mJy and micro-Jy at 325 and 1425 MHz, respectively, equivalent to planetary luminosity limits of 2.3 x 10(exp 24) erg/s and 2.7 x 10(exp 23) erg/s. Unfortunately, these ... |
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| Size and Albedo of Kuiper Belt Object 55636 from a Stellar Occultation |
JUN 2010 |
5 pages |
| Authors:
J. L. Elliot; M. J. Person; C. A. Zuluaga; A. S. Bosh; E. R. Adams; T. C. Brothers; A. A. Gulbis; S. E. Levine; M. Lockhart; A. M. Zangari; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The Kuiper belt is a collection of small bodies (Kuiper belt objects, KBOs) that lie beyond the orbit of Neptune and which are believed to have formed contemporaneously with the planets. Their small size and great distance make them difficult to study. KBO 55636 (2002 TX300) is a member of the water-ice-rich Haumea KBO collisional family. The Haumea family are among the most highly reflective objects in the Solar System. ... |
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| Selection, Prioritization, and Characteristics of Kepler Target Stars |
20 Apr 2010 |
7 pages |
| Authors:
Natalie M Batalha; William J Borucki; David G Koch; Stephen T Bryson; Michael R Hass; Timothy M Brown; Douglas A Caldwell; Jennifer R Hall; Ronald L ; David W Latham; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The Kepler Mission began its 3.5 year photometric monitoring campaign in 2009 May on a select group of approximately 150,000 stars. The stars were chosen from the approximately half million in the field of view that are brighter than 16th magnitude. The selection criteria are quantitative metrics designed to optimize the scientific yield of the mission with regard to the detection of Earth-size planets in the habitable zone. This yields ... |
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| Kepler-7b: A Transiting Planet With Unusually Low Density |
20 Apr 2010 |
6 pages |
| Authors:
David W Latham; William J Borucki; David G Koch; Timothy M Brown; Lars A Buchhave; Gibor Basri; Natalie M Batalha; Douglas A Caldwell; William D Cochran; Edward W Dunham; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| We report on the discovery and confirmation of Kepler-7b, a transiting planet with unusually low density. The mass is less than half that of Jupiter, M(p) = 0.43M(j), but the radius is 50% larger, R(p) = 1.48R(j). The resulting density, Rho(p) = 0.17 g cm( -3), is the second lowest reported so far for an extrasolar planet. The orbital period is fairly long, P = 4.886 days, and the host ... |
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| Kepler Mission Design, Realized Photometric Performance, and Early Science |
20 Apr 2010 |
9 pages |
| Authors:
David G Koch; William J Borucki; Gibor Basri; Natalie M Batalha; Timothy M Brown; Douglas Caldwell; Joergen Christensen-Dalsgaard; William D Cochran; Edna DeVore; Edward W Dunham; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The Kepler Mission, launched on 2009 March 6, was designed with the explicit capability to detect Earth-size planets in the habitable zone of solar-like stars using the transit photometry method. Results from just 43 days of data along with ground-based follow-up observations have identified five new transiting planets with measurements of their masses, radii, and orbital periods. Many aspects of stellar astrophysics also benefit from the unique, precise, extended, and ... |
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| Kepler-4b: A Hot Neptune-Like Planet of a G0 Star Near Main-Sequence Turnoff |
20 Apr 2010 |
6 pages |
| Authors:
William J Borucki; David G Koch; Timothy M Brown; Gibor Basri; Natalie M Batalha; Douglas A Caldwell; William D Cochran; Edward W Dunham; III Gautier Thomas N; John C Geary; Ronald L Gilliland; Steve B Howell; Jon M Jenkins; David W Latham; Jack J Lissauer; Geoffrey W Marcy; David Monet; Jason F Rowe; Dimitar Sasselov; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| Early time-series photometry from NASA's Kepler spacecraft has revealed a planet transiting the star we term Kepler-4, at R.A. = 19h02m27.s68, declination = +50 deg 08 min 08 sec.7. The planet has an orbital period of 3.213 days and shows transits with a relative depth of 0.87 x 10(exp -3) and a duration of about 3.95 hr. Radial velocity (RV) measurements from the Keck High Resolution Echelle Spectrometer show a ... |
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| Kepler-6b: A Transiting Hot Jupiter Orbiting a Metal-Rich Star |
20 Apr 2010 |
5 pages |
| Authors:
Edward W Dunham; William J Borucki; David G Koch; Natalie M Batalha; Lars A Buchhave; Timothy M Brown; Douglas A Caldwell; William D Cochran; Michael Endl; Debra Fischer; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The Kepler Mission was launched on 2009 March 6, to undertake a search for Earth-size planets orbiting in the habitable zones of stars similar to the Sun. Kepler uses the transit photometry approach for this task (Borucki et al. 2010a). Kepler s commissioning process went very well and the system provides data of exceptional photometric quality (Koch et al. 2010a). Indeed, the final commissioning data, 9.7 days of science-like observations ... |
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| Kepler Planet-Detection Mission: Introduction and First Results |
19 Feb 2010 |
6 pages |
| Authors:
William J Borucki; David Koch; Gibor Basri; Natalie Batalha; Timothy Brown; Douglas Caldwell; John Caldwell; Joergen Christensen-Dalsgaard; William D Cochran; Edna DeVore; Edward W Dunham; Andrea K Dupree; III Gautier Thomas N; John C Geary; Ronald Gilliland; Alan Gould; Steve B Howell; Jon M Jenkins; Yoji Kondo; David W Latham; NAVAL OBSERVATORY FLAGSTAFF AZ
|
| The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet's surface. During the first 6 weeks of observations, Kepler monitored 156,000 stars, and five new exoplanets with sizes between 0.37 and 1.6 Jupiter radii and orbital periods from 3.2 to 4.9 ... |
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| Non-Equilibrium Gas Dynamics - From Physical Models to Hypersonic Flights (Dynamique des gaz non- equilibres - Des modeles physiques jusqu'au vol hypersonique) |
Sep 2009 |
|
| Authors:
NATO RESEARCH AND TECHNOLOGY ORGANIZATION NEUILLY-SUR-SEINE (FRANCE)
|
 | In-depth knowledge of gas dynamics at hypersonic speeds is required to define the environment and requirements for the design and safe operation of space vehicles, planetary probes, and rockets. Development of physical models and numerical methods has enabled major advancements in our approach to the design of vehicles, and has minimized the needs for extensive flight tests. However, there remain many challenges in our ability to model the hypersonic regime. ... |
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| Joint Milli-Arcsecond Pathfinder Survey (JMAPS): Overview and Application to NWO Mission |
11-Mar-2009 |
15 pages |
| Authors:
B Dorland; R Dudik; NAVAL OBSERVATORY WASHINGTON DC
|
| The Joint Milli-Arcsecond Pathfinder Survey (JMAPS) mission is a Department of Navy (DoN) space-based, all-all sky astrometric bright star survey, current set with a 2012 launch date. JMAPS will use a relatively modest aperture, very high accuracy astrometric telescope flown in low earth orbit aboard a microsat. Mission baseline is for a three-year mission life (2012-2015) in a 900 km sun synchonous terminator orbit. JMAPS will produce an all-sky astrometric, ... |
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| Enhancing the Art of Space Operations - Progress in JHU/APL Ultra-Stable Oscillator Capabilities |
01-Dec-2008 |
13 pages |
| Authors:
Gregory Weaver; Matthew Reinhart; Robert Wallis; JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
|
| The Johns Hopkins University Applied Physics Laboratory (JHU/APL) Ultra-stable Oscillator (USO) has been demonstrated in nearly 50 years of space applications to be a strategic asset to the space timekeeping and signal technologies of the United States. Therefore, advancing the JHU/APL USO capability by improving its frequency stability, without diminishing reliability, is uniquely valuable to the operations of space communication and navigation systems. Ultimately, we expect that the call for ... |
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| Further Constraints on the Presence of a Debris Disk in the Multiplanet System Gliese 876 |
JUN 2008 |
6 pages |
| Authors:
P. D. Shankland; D. L. Blank; D. A. Boboltz; T. J. Lazio; G. White; NAVAL OBSERVATORY WASHINGTON DC
|
| Using both the Very Large Array (VLA) at 7 mm wavelength, and the Australia Telescope Compact Array (ATCA) at 3 mm, we have searched for microwave emission from cool dust in the extrasolar planetary system Gliese 876 (Gl 876). Having detected no emission above our 3 sigma detection threshold of 135 microJy, we rule out any dust disk with either a mass greater than 0.0006 Earth mass or less than ... |
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| Multiple Stars in the Field |
2008 |
19 pages |
| Authors:
Brian D. Mason; William I. Hartkopf; NAVAL OBSERVATORY WASHINGTON DC
|
| When examining the statistics of multiple stars in the field, especially coming from visual binary star point of view, several problems present themselves. First, and most importantly, is distinguishing between physical multiples and optical pairs. Establishing physicality is not a simple "binary" response as there are degrees of certainty. We discuss some of the reasons for caring about non-physical pairs, as well as the tools for establishing or more correctly ... |
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| Numerical Implementation of Surface Catalysis, Reaction, and Sublimation |
01 JUL 2007 |
21 pages |
| Authors:
Chul Park; KOREA ADVANCED INST OF SCIENCE AND TECHNOLOGY DAEJEON (KOREA)
|
| This lecture consists of three parts: 1) quantification of rates of gas-surface interaction, 2) formulation of gas-surface balance conditions, and 3) survey of the gas-surface interaction problems in the entry flights of various planets. The first part reviews the role of surface rates and flow parameters in Goulard's theory, the catalytic rates for Martian entry problem, the reaction rates for oxidation and nitridation of carbon, rough surfaces, and the relationship ... |
|
| Fine Pointing of Military Spacecraft |
MAR 2007 |
154 pages |
| Authors:
Timothy A. Sands; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| In 1923, Herman Oberth, considered by some to be the father of it all for space flight, wrote a book called Die Rakete zu den Planetraeumen (i.e., Dreams of Planets ) inspiring today's modern space flight. Amongst his suggestions was placing a telescope in space, so astronomical observations may be made without atmospheric distortion. Nearly a century later, the Hubble Space telescope is imaging distant stars with high accuracy. If ... |
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| The Space Infrared Interferometric Telescope (SPIRIT): High-Resolution Imaging and Spectroscopy in the Far-Infrared (Preprint) |
01-Jan-2007 |
21 pages |
| Authors:
David Leisawitz; John Carpenter; Jason Budinoff; Richard Broderick; Rob Boyle; Andrew Blain; Dominic Benford; Amy Barger; Charles Baker; Richard Caverly; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GREENBELT MD GODDARD SPACE FLIGHT CENTER
|
| We report results of a recently-completed pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 microns. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how ... |
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| Planets for Man |
2007 |
|
| Authors:
Stephen Dole; Isaac Asimov; RAND CORP SANTA MONICA CA
|
| "Planets for Man" was written at the height of the space race, a few years before the first moon landing, when it was assumed that in the not-too-distant future human beings "will be able to travel the vast distances to other stars." The authors propose to determine-on the basis of then-current biological and cosmological knowledge - whether there are other worlds where humans can survive or where human life may ... |
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| Habitable Planets for Man |
2007 |
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| Authors:
Stephen H. Dole; RAND CORP SANTA MONICA CA
|
| "Habitable Planets for Man" examines and estimates the probabilities of finding planets habitable to human beings, where they might be found, and the number there may be in our own galaxy. The author presents in detail the characteristics of a planet that can provide an acceptable environment for humankind, itemizes the stars nearest the earth most likely to possess habitable planets, and discusses how to search for habitable planets. Interestingly ... |
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| The Serret-Andoyer Formalism in Rigid-Body Dynamics: 1. Symmetries and Perturbations |
2007 |
38 pages |
| Authors:
P. Gurfil; A. Elipe; W. Tangren; M. Efroimsky; NAVAL OBSERVATORY WASHINGTON DC
|
| This paper reviews the Serret Andoyer (SA) canonical formalism in rigid-body dynamics, and presents some new results. As is well known, the problem of unsupported and unperturbed rigid rotator can be reduced. The availability of this reduction is offered by the underlying symmetry, that stems from conservation of the angular momentum and rotational kinetic energy. When a perturbation is turned on, these quantities are no longer preserved. Nonetheless, the language ... |
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| Taking the Measure of the Universe: Precision Astrometry with SIM Planetquest (Preprint) |
09 OCT 2006 |
49 pages |
| Authors:
Stephen C. Unwin; Michael Shao; Angelle M. Tanner; Ronald J. Allen; Charles A. Beichman; David Boboltz; Joseph H. Catanzarite; Brian C. Chaboyer; David R. Ciardi; Stephen J. Edberg; CALIFORNIA INST OF TECHNOLOGY PASADENA JET PROPULSION LAB
|
| Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument with flexible scheduling that delivers parallaxes at about 4 microarcsecond on targets as faint as V = 20, and differential accuracy of 0.6 microarchsecond on bright targets. The science topics are drawn primarily from the Team Key Projects, selected in ... |
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| The Search for Planet X: Testing Inferences from the Kuiper Cliff |
04 MAY 2006 |
158 pages |
| Authors:
Eric A. Roe; NAVAL ACADEMY ANNAPOLIS MD
|
| The goal of this project was to search a large archive of astronomical CCD imagery to test the validity of arguments regarding the existence of a hypothetical "Planet X." As proposed by Brunini and Melita (2002) this object would be a low inclination Mars-sized body residing in the Kuiper belt between 55 and 75 astronomical units from the Sun. Resonances with this hypothetical planet form a convenient explanation of the ... |
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| A Survey of Stellar Families: Multiplicity Among Solar-Type Stars |
2006 |
5 pages |
| Authors:
Deepak Raghavan; H. A. McAlister; T. J. Henry; B. D. Mason; NAVAL OBSERVATORY WASHINGTON DC
|
| Stellar multiplicity is a fundamental astrophysical property. In addition to being the only physical basis for accurate mass determination, this parameter is believed to influence important aspects such as planet formation and stability. Contrary to earlier expectations, recent studies have shown that even against selection biases, as many as 23% of the planetary systems reside in multiple star systems (Raghavan et al. 2006). Leveraging recent efforts in identifying stellar and ... |
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| The Kepler Mission and Eclipsing Binaries |
2006 |
9 pages |
| Authors:
David Koch; William Borucki; Gibor Basri; Timothy Brown; Douglas Caldwell; Jorgen Christensen-Dalsgaard; William Cochran; Edna DeVore; Edward Dunham; Thomas N. Gautier; NAVAL OBSERVATORY WASHINGTON DC
|
| The Kepler Mission is a space-based photometric mission with a differential photometric precision of 14 ppm (at V = 12 for a 6.5 hour transit). It is designed to continuously observe a single field of view (FOV) of greater then 100 square degrees in the Cygnus-Lyra region for four or more years. The primary goal of the mission is to monitor more than one-hundred thousand stars for transits of Earth-size ... |
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| The APL Time And Frequency Lab |
SEP 2004 |
7 pages |
| Authors:
R. A. Dragonette; M. Miranian; M. J. Reinhart; JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
|
| The APL Time and Frequency Laboratory supports a wide variety of current and upcoming NASA missions that span the solar system from the study of the Sun's coronal mass ejections to the examination of the planet Pluto and the Kuiper Belt objects. This support can be in the form of providing precise time and frequency to the integration and testing of new hardware or the time- stamping of ground-receipt telemetry ... |
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| Derivation of a Self-Consistent Auroral Oval Model Using the Auroral Boundary Index |
JUN 2004 |
110 pages |
| Authors:
Keith A. Anderson; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| The position and intensity of the auroral oval has many implications for the Air Force from determining the effects of incoming electron flux on DoD systems to modeling the ionosphere to exploit current HF communications capabilities. The auroral morphology is a good indicator of the level at which space weather and its near-Earth consequences are occurring, and thus it is important to develop an auroral prediction model. However, since no ... |
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| Bounds on Turbulent Transport |
JUL 2003 |
|
| Authors:
John A. Whitehead; Friedrich Busse; Louis Howard; Charles Doering; Peter Constantin; WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
|
| The subject of "Bounds on Turbulent Transport" was introduced in a series of ten lectures. The six lecturers constitute almost all of the contributors to this subject. The subject was introduced and foundations were laid by five lectures by F. H. Busse. In the middle of the first week, L. Howard reviewed his historical first approach to this subject and described more recent advances. Additional lectures by P. Constantine, R. ... |
|
| Space, Time and Life |
16 DEC 2002 |
65 pages |
| Authors:
S. D. Bosanac; RUDER BOSKOVIC INST ZAGREB (CROATIA)
|
| The Book of Abstracts for papers presented: Space, time and Life, 26 August 2002 - 30 August 2002. Some topics include Structure and evolution of the universe, life and entropy, and nano-scale phenomena. |
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| Climatological Fit to the Ionospheric Parameters f0F2 and hmF2 for the High Latitude Stations at Sondrestrom, Greenland, and Qaanaaq, Greenland |
11 JUL 2002 |
23 pages |
| Authors:
Balkrishna S. Dandekar; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| Ionospheric data from the high latitude stations Sondrestrom, Greenland, and Qaanaaq, Greenland, for a period of 8 years, covering a good range of solar cycle variation, are used to derive empirical algorithms for the prediction of foF2 and hmF2. The algorithm connects these two parameters with diurnal, seasonal, 90-day averaged solar flux at 2800 MHz and the planetary geomagnetic activity index Kp. The Sondrestrom station sees foF2 inhancement due to ... |
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| Peculiarities of Gasdynamics of Descent and Landing on Planets with Rarefield Atmosphere |
JUL 2002 |
|
| Authors:
A. A. Bachin; E. M. Kalinin; V. I. Lapygin; N. E. Khramov; CENTRAL SCIENTIFIC RESEARCH INST OF TECH AND MACHINE BUILDING MOSCOW (USSR)
|
| TSNIIMash was one of the first scientific centers were such investigations had been started dealing with force and heat loads from the engine jets acted on the space vehicle structure during soft landing on the lunar and Martian surfaces. Interaction of single/multiple jet with oncoming flow or surface is characterized by appearance of a large number of shock waves contact surfaces separated zones and other peculiarities and this defined the ... |
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| Planetary and Topographic Beta Effects on the Northern Canary Current System (NCCS) |
DEC 2001 |
97 pages |
| Authors:
Wendy A. Towle; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| To investigate planetary and topographic beta effects on classical as well as unique features in the northern Canary Current system (NCCS), several numerical experiments using the Princeton Ocean Model are explored To isolate the dependence of Coriolis parameterization (beta-plane vs, f-plane) from the topographic beta effect, the first (last) two experiments use a flat bottom (topography), In all experiments, classical eastern boundary condition (EBC) features are produced including an offshore ... |
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| Modeling, Modal Properties, and Mesh Stiffness Variation Instabilities of Planetary Gears |
MAY 2001 |
121 pages |
| Authors:
Robert G. Parker; Jian Lin; OHIO STATE UNIV COLUMBUS DEPT OF MECHANICAL ENGINEERING
|
| Planetary gear noise and vibration are primary concerns in their applications in helicopters, automobiles, aircraft engines, heavy machinery, and marine vehicles. Dynamic analysis is essential to the noise and vibration reduction. This work analytically investigates some critical issues and advances the understanding of planetary gear dynamics. A lumped-parameter model is built for the dynamic analysis of general planetary gears. The unique properties of the natural frequency spectra and vibration modes ... |
|
| Celestial Background Scene Descriptor: Final Report |
FEB 2001 |
89 pages |
| Authors:
P. V. Noah; M. A. Noah; MISSION RESEARCH CORP SANTA BARBARA CA
|
| This report summarizes the results of the Celestial Background Scene Descriptor (CBSD) program. The goal of the CBSD program is to design, build, and validate a suite of FORTRAN codes that simulates the flux from the celestial background, in support of DoD developed optical and infrared sensor systems, realistic scenario generation, and the development of clutter removal algorithms. Components of the CBSD suite are CBSKY4 - stellar point sources (both ... |
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| New Research in Sky Surveillance - Interpretation of Low-Luminosity Objects |
15 DEC 2000 |
18 pages |
| Authors:
Robert S. McMillan; STEWARD OBSERVATORY TUCSON AZ
|
| Spacewatch is an exploration of the whole solar system for minor planets and comets, from the inner solar system to beyond Neptune's orbit. During this report period, Spacewatch discovered 23 Earth-approachers (EAs), 9, 910 main belt asteroids (MBAs), a new satellite of Jupiter, 2 comets, 9 Centaurs or scattered-disk objects, and 6 Trans-Neptunian Objects (TNOs). Spacewatch made a new estimate of the number of km-sized EAs, from which it has ... |
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| US/European Celestial Mechanics Workshop Held in Poznan (Poland) on July 3-7, 2000 |
07 JUL 2000 |
94 pages |
| Authors:
COURTER PRODUCTS BOYNE CITY MI
|
| The Final Proceedings for US/European Celestial Mechanics Workshop, 3 September 2000 - 4 September 2000 1. Chaos, Resonances & Stability 2. Kulper Belt Objects 3. Satellites, Minor Planets, Comets, and Meteors 4. Orbit Uncertainty and Error Analysis for NEO and Artificial Satellites 5. Stellar and Galactic Dynamics * 6. Drag and Atmospheric Modeling & Theory (Non-gravitational Force Modeling) 7. Numerical Methods, Parallel Processing, Ephemeris Generation 8. Satellite Constellation Dynamics and ... |
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| Distant Comets in the Early Solar System |
23 MAY 2000 |
7 pages |
| Authors:
Karen Meech; HAWAII UNIV HONOLULU INST FOR ASTRONOMY
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| The main goal of this project is to physically characterize the small outer solar system bodies. One of planetary science's highest priorities is an understanding of the dynamics and physical properties of the outer solar system small bodies. The measurement of the size distribution of these bodies will help constrain the early mass of the outer solar system as well as lead to an understanding of the ... |
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| Measurement Requirements for Improved Modeling of Arcjet Facility Flows |
APR 2000 |
27 pages |
| Authors:
Douglas G. Fletcher; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCHCENTER
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| Current efforts to develop new reusable launch vehicles and to pursue low-cost robotic planetary missions have led to a renewed interest in understanding arcjet flows. Part of this renewed interest is concerned with improving the understanding of arcjet test results and the potential use of available computational-fluid-dynamic (CFD) codes to aid in this effort. These CFD codes have been extensively developed and tested for application to nonequilibrium hypersonic flow modeling. ... |
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| Dynamical Reference Frame - Current Relevance and Future Prospects |
MAR 2000 |
8 pages |
| Authors:
E. M. Standish Jr; JET PROPULSION LAB PASADENA CA
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| Planetary and lunar ephemerides are no longer used for the determination of inertial space. Instead, the new fundamental reference frame, the International Celestial Reference Frame (ICRF), is inherently less susceptible to extraneous, non-inertial rotations than a dynamical reference frame determined by the ephemerides would be. Consequently, the ephemerides are now adjusted onto the ICRF, and they are fit to two modern, accurate observational data types: ranging (radar, lunar laser, spacecraft) ... |
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| Numerical Data-Processing Simulation of Microarcsecond Classical and Relativistic Effects in Space Astrometry |
MAR 2000 |
8 pages |
| Authors:
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| The accuracy of astrometric observations conducted via a space-borne optical interferometer orbiting the Earth is expected to approach a few microarcseconds. Data processing of such extremely high-precision measurements requires access to a rigorous relativistic model of light ray propagation developed in the framework of General Relativity. The data processing of the space interferometric observations must rely upon the theory of general- relativistic transformations among the spacecraft, geocentric, and solar barycentric ... |
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| Planetary Defense: Eliminating the Giggle Factor |
2000 |
26 pages |
| Authors:
Martin E. France; NATIONAL DEFENSE UNIV WASHINGTON DC
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| The Giggle Factor (GF). Mention Planetary Defense and you'll soon understand. Even without invoking the sinister vision of alien beings arriving to enslave or destroy humanity, the eyebrows of serious and senior members of the national defense and scientific communities go askew when the subject is broached, whether at cocktail parties or congressional budget hearings. Even the most ardent supporters of defending the Earth from cataclysmic cometary or asteroidal impacts ... |
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| Spectroscopic Observations of the Planets |
04 MAY 1999 |
4 pages |
| Authors:
Tobias C. Owen; HAWAII UNIV HONOLULU INST FOR ASTRONOMY
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| The research supported by this grant has focused on isotopic ratios in comets and in the atmosphere of Titan, and the determinations of surface compositions of outer solar system bodies. |
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Reports by Keyword(s)
PLANETS
