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We report on spectroscopic observations of periodic comet 9P/Tempel 1 by the Alice ultraviolet spectrograph on the Rosetta spacecraft in conjunction with NASA's Deep Impact mission. Our objectives were to measure an increase in atomic and molecular emissions produced by the excavation of volatile sub-surface material. We unambiguously detected atomic oxygen emission from the quiescent coma but no enhancement at the 10% (1-sigma) level following the impact. We derive a quiescent water production rate of 9 x 10^27 molecules per second with an estimated uncertainty of 30%. Our upper limits to the volatiles produced by the impact are consistent with other estimates., 11 pages, 4 postscript figures. Accepted for publication in Icarus special issue on Deep Impact

The New Horizons spacecraft will achieve a wide range of measurement objectives at the Pluto system, including color and panchromatic maps, 1.25-2.50 micron spectral images for studying surface compositions, and measurements of Pluto's atmosphere (temperatures, composition, hazes, and the escape rate). Additional measurement objectives include topography, surface temperatures, and the solar wind interaction. The fulfillment of these measurement objectives will broaden our understanding of the Pluto system, such as the origin of the Pluto system, the processes operating on the surface, the volatile transport cycle, and the energetics and chemistry of the atmosphere. The mission, payload, and strawman observing sequences have been designed to acheive the NASA-specified measurement objectives and maximize the science return. The planned observations at the Pluto system will extend our knowledge of other objects formed by giant impact (such as the Earth-moon), other objects formed in the outer solar system (such as comets and other icy dwarf planets), other bodies with surfaces in vapor-pressure equilibrium (such as Triton and Mars), and other bodies with N2:CH4 atmospheres (such as Titan, Triton, and the early Earth)., Comment: 40 pages, 9 figures, 7 tables; To appear in a special volume of Space Science Reviews on the New Horizons mission

The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments that will collect and return data from Pluto in 2015. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration needed to reach the Pluto system prior to the year 2020. The spacecraft subsystems were designed to meet tight mass and power allocations, yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto flyby is 4.5 hours. Missions to the outer solar system require a radioisotope thermoelectric generator (RTG) to supply electrical power, and a single RTG is used by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on less than 200 W. The spacecraft system architecture provides sufficient redundancy to provide a probability of mission success of greater than 0.85, even with a mission duration of over 10 years. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial inflight tests have verified that the spacecraft will meet the design requirements., Comment: 33 pages, 13 figures, 4 tables; To appear in a special volume of Space Science Reviews on the New Horizons mission

N2 is abundant in Pluto’s atmosphere and on its surface, but the supply is depleted by prodigious atmospheric escape. We demonstrate that cometary impacts could not have delivered enough N mass to resupply Pluto’s N2 atmospheric escape over time; thus Pluto’s N2 is likely endogenous, and therefore was either acquired early in its history or created by chemistry inside Pluto. We find that cratering could excavate a considerable amount of N2 to resupply the atmosphere against escape if the near-surface N2 reservoir is deep. However, we find that this process likely falls short of that necessary to resupply the atmosphere against escape by at least an order of magnitude. We conclude that either the escape of N2 from Pluto’s atmosphere was on average much lower than the predictions for the current epoch, or that internal activity could be necessary to bring N2 to the surface and resupply escape losses. Observations made by the New Horizons spacecraft in mid-2015 will yield further constraints on the provenance and evolution of Pluto’s surface and atmospheric N2, and could reveal evidence for past or present internal activity.

Next week, the New Horizons spacecraft will reconnoiter Pluto and its system of moons on the ragged edge of our planetary system. It may then fly by icy bodies in the Kuiper Belt, more than a billion kilometers beyond Neptune's orbit. These will become the farthest worlds ever explored, ushering in a new era of discovery. Although information from previous planetary probes has helped scientists understand the origin of the inner rocky planets (Mercury, Venus, Earth, and Mars) and the gas giants (Jupiter, Saturn, Uranus, and Neptune), as well as their moons, this will be the first opportunity to undertake a close-up study of the dwarf planets that are so common beyond Neptune.

New Frontier. First Facts. A Distant Dance. Another Snow. Building a Binary Planet. Icefields and Ice Dwarfs. Everest. Postscript: Where No One Has Gone Before. A Chronology of Major Events in the Exploration of Pluto. Suggested Readings. Index.

We present new optical emission-line images of the young SNR 1E 0102-7219 (E0102) in the SMC obtained with the HST Advanced Camera for Surveys (ACS). E0102 is a member of the oxygen-rich class of SNRs showing strong oxygen, neon , and other metal-line emissions in its optical and X-ray spectra, and an absence of H and He. The progenitor of E0102 may have been a Wolf-Rayet star that underwent considerable mass loss prior to exploding as a Type Ib/c or IIL/b SN. The ejecta in this SNR are fast-moving (V > 1000 km/s) and emit as they are compressed and heated in the reverse shock. In 2003, we obtained optical [O III], H-alpha, and continuum images with the ACS Wide Field Camera. The [O III] image captures the full velocity range of the ejecta, and shows considerable high-velocity emission projected in the middle of the SNR that was Doppler-shifted out of the narrow F502N bandpass of a previous Wide Field and Planetary Camera 2 image from 1995. Using these two epochs separated by ~8.5 years, we measure the transverse expansion of the ejecta around the outer rim in this SNR for the first time at visible wavelengths. From proper-motion measurements of 12 ejecta filaments, we estimate a mean expansion velocity for the bright ejecta of ~2000 km/s and an inferred kinematic age for the SNR of \~2050 +/- 600 years. The age we derive from HST data is about twice that inferred by Hughes et al.(2000) from X-ray data, though our 1-sigma error bars overlap. Our proper-motion age is consistent with an independent optical kinematic age derived by Eriksen et al.(2003) using spatially resolved [O III] radial-velocity data. We derive an expansion center that lies very close to X-ray and radio hotspots, which could indicate the presence of a compact remnant (neutron star or black hole)., 28 pages, 8 figures. Accepted to the Astrophysical Journal, to appear in 20 April 2006 issue. Full resolution figures are posted at: http://stevenf.asu.edu/figures

The ALICE instrument is a lightweight (4.4 kg), low-power (4.4 W) imaging spectrograph that is planned to fly aboard the New Horizons mission to Pluto/Charon and the Kuiper Belt. Its primary job is to detect a variety of important atomic and molecular species in Pluto's atmosphere, and to determine their relative abundances as a function of altitude so that a complete picture of Pluto's atmospheric composition and structure can be determined for the first time. ALICE would also be used to search for an atmosphere around Pluto's mo on, Charon, as well as the Kuiper Belt Objects (KBOs) that New Horizons hopes to fly by after Pluto-Charon. The New Horizons ALICE design, based on the Rosetta ALICE instrument design now en route to Comet 67P/ Churyumov-Gerasimenko aboard the European Space Agency’s Rosetta spacecraft, incorporates an off-axis telescope feeding a Rowland-circle spectrograph with a 520-1870 A spectral passband, a spectral point spread function of 3-6 A FWHM, and an instantaneous spatial field-of-view of 6 degrees. Two separate input apertures that feed the telescope allow for both airglow and solar occultation observations during the mission. The focal plane camera is an imaging microchannel plate (MCP) double delay-line detector with dual solar-blind opaque photocathodes (KBr and CsI) and a focal surface that matches the 15-cm diameter Rowland-circle. Data taking modes include both histogram and pixel list exposures. We describe the scientific objectives of ALICE as well as the design, build, and environmental testing results of the flight model. Keywords: UV spectroscopy, New Horizons, Pluto, Charon, Kuiper Belt Objects

We describe the radiometric performance and calibration results of the New Horizons' ALICE flight model. This ALICE is a lightweight (4.4 kg), low-power (4.4 W), ultraviolet spectrograph based on the ALICE instrument now in flight aboard the European Space Agency's Rosetta spacecraft. Its primary job will be to detect a variety of important atomic and molecular species in Pluto's atmosphere, and to determine their relative abundances so that a complete picture of Pluto's atmospheric composition can be determined for the first time. ALICE will also be used to search for an atmosphere around Pluto's moon, Charon, as well as the Kuiper Belt Objects (KBOs) New Horizons hopes to fly by after Pluto-Charon. Detailed radiometric performance results of the ALICE flight model are presented and discussed.

The Lyman Alpha Mapping Project (LAMP) is an ultraviolet imaging spectrograph recently selected for NASA's Lunar Reconnaissance Orbiter (LRO) mission. Its main objectives are to (i) identify and localize exposed water frost in permanently shadowed regions (PSRs), (ii) characterize landforms and albedos in PSRs, (iii) demonstrate the feasibility of using natural starlight and sky-glow illumination for future lunar surface mission applications, and (iv) characterize the lunar atmosphere and its variability. The LAMP UV spectrograph will accomplish these objectives by measuring the signal reflected from the nightside lunar surface and in PSRs using both the interplanetary HI Lyman-α sky-glow and FUV starlight as light sources. Both these light sources provide fairly uniform, but faint, illumination (e.g., the reflected Lyman-α signal is expected to be ~10 R). Thanks to LAMP's sensitivity, by the end of the 1-year LRO mission the SNR for a Lyman-α albedo map will be >100 in polar regions exceeding 1 km 2 (and >15 for 100×100 m 2 polar regions), allowing the characterization of subtle compositional and structural features. The LAMP instrument is based on the flight-proven ALICE series of spectrographs that are flying on Rosetta and built for flight on NASA's New Horizons Pluto-Kuiper Belt Mission.

The International Rosetta Mission was successfully launched on March 2, 2004. NASA's contribution to this mission consists of the following three hardware experiments: Alice (an ultraviolet spectrometer), the ion and electron sensor (IES - a plasma instrument), and the microwave instrument for the Rosetta orbiter (MIRO), as well as other components. Collectively these elements are known as the U.S. Rosetta project. In this paper, we present an overview of the U.S. Rosetta project. We present and summarize the successful launch and early operations phases of the U.S. Rosetta project. Finally, an unplanned science target appeared in the form of Comet C/2002 T7 (LINEAR). Comet Linear was successfully observed by the U.S. Rosetta project on two occasions, April 30 and May 17, 2004, by both Alice and MIRO.

Development of the New Horizons mission to Pluto and the Kuiper Belt is now fully funded by NASA (Stern and Spencer, this volume). If all goes well, New Horizons will be launched in January 2006, followed by a Jupiter gravity assist in 2007, with Pluto arrival expected in either 2015 or 2016, depending on the launch vehicle chosen. A backup launch date of early 2007, without a Jupiter flyby, would give a Pluto arrival in 2019 or 2020. In either case, a flyby of at least one Kuiper Belt object (KBO) is planned following the Pluto encounter, sometime before the spacecraft reaches a heliocentric distance of 50 AU, in 2021 or 2023 for the 2006 launch, and 2027 or 2029 for the 2007 launch. However, none of the almost 1000 currently-known KBOs will pass close enough to the spacecraft trajectory to be targeted by New Horizons, so the KBO flyby depends on finding a suitable target among the estimated 500,000 KBOs larger than 40 km in diameter. This paper discusses the issues involved in finding one or more KBO targets for New Horizons. The New Horizons team plans its own searches for mission KBOs but will welcome other U.S, or international team who wish to become involved in exchange for mission participation at the KBO.

The Mars Atmospheric Constellation Observatory (MACO) represents an innovative approach to characterizing the present Martian climate from the surface into the thermosphere including the hydrological, CO2, and dust cycles together with the energy and momentum budgets. The mission concept is based on a constellation of satellites forming counter-rotating pairs for observing satellite-to-satellite microwave occultations to determine vertical profiles of water vapor, CO2, temperature, pressure, and wind. Satellite radio occultation, used in previous missions such as Mars Global Surveyor (MGS), provides precision, accuracy and vertical resolution typically 1 and sometimes 2 orders of magnitude beyond that of passive radiometers. Furthermore it can measure absolute pressure versus height (which is unobservable by radiometers) and thus remotely determine seasonal CO2 changes and winds. The microwave observations are supplemented by IR observations by a Dust and Ice Sensor (DIS). With the addition of a UV spectrometer, MACO can characterize the upper atmosphere’s composition and thermodynamic structure as well as escape rates. With a three satellite constellation, MACO will sample the Martian atmosphere with more than 80 occultations each day and, with observations from rapidly precessing orbits over at least one Martian year, will characterize the diurnal and seasonal cycles.

NASA has long been planning a mission of exploration to Pluto-Charon and the Kuiper Belt (e.g., Terrile et al., 1997). In 2001 NASA selected such a mission (NASA, 2001), called New Horizons, for design and development. New Horizons is now funded and planning a launch in January 2006. The mission plans to carry 8 scientific sensors and make flybys of Pluto-Charon and one or more KBOs. Statistical Monte Carlo simulations indicate that New Horizons has sufficient fuel to reach one or more KBOs with diameters exceeding 35 km. If launched as planned in 2006, the mission will use a Jovian gravity assist, arriving at Pluto-Charon in 2015 or 2016; if launched in its backup window in 2007, a Jovian gravity assist is not feasible and arrival will be later — 2019. Below we briefly summarize the New Horizons mission, concentrating on its role in Kuiper Belt exploration.

Amyloid-beta peptide (Abeta) interacts with the vasculature to influence Abeta levels in the brain and cerebral blood flow, providing a means of amplifying the Abeta-induced cellular stress underlying neuronal dysfunction and dementia. Systemic Abeta infusion and studies in genetically manipulated mice show that Abeta interaction with receptor for advanced glycation end products (RAGE)-bearing cells in the vessel wall results in transport of Abeta across the blood-brain barrier (BBB) and expression of proinflammatory cytokines and endothelin-1 (ET-1), the latter mediating Abeta-induced vasoconstriction. Inhibition of RAGE-ligand interaction suppresses accumulation of Abeta in brain parenchyma in a mouse transgenic model. These findings suggest that vascular RAGE is a target for inhibiting pathogenic consequences of Abeta-vascular interactions, including development of cerebral amyloidosis.

THE presence of dust around normal (main-sequence) stars is a possible signature of the early stages of planet formation. Scattered light from the star β Pictoris provides evidence of a dust disk extending out to about 1,000 astronomical units1, and the observation of far-infrared excess emission from several other main-sequence stars2 suggests the presence of orbiting cold dust grains3. Because the dynamical lifetime of this dust is short, it is thought to be supplied and replenished by collisions among a population of comets or asteroids4–8. Observations by Chini et al. 9,10 of β Pic and several other infrared-excess stars at a wave-length of 1.3 mm have supported the idea that they are surrounded by extended dust disks. Techniques developed recently now permit imaging at these wavelengths, and we have used these techniques to obtain a map of the dust disk around the nearby, prototypical infrared-excess star Fomalhaut with a spatial resolution of 80 au. This image provides direct confirmation that the dust is distributed in a disk-like structure, and shows that the structure extends about 200 au from the star, farther than estimated previously9,10. We estimate that a high rate of cometary and/or asteroidal collisions is required to maintain this disk.

Multiple sclerosis (MS) is a devastating neuroinflammatory disorder of the central nervous system (CNS) in which T cells that are reactive with major components of myelin sheaths have a central role. The receptor for advanced glycation end products (RAGE) is present on T cells, mononuclear phagocytes and endothelium. Its pro-inflammatory ligands, S100-calgranulins, are upregulated in MS and in the related rodent model, experimental autoimmune encephalomyelitis (EAE). Blockade of RAGE suppressed EAE when disease was induced by myelin basic protein (MBP) peptide or encephalitogenic T cells, or when EAE occurred spontaneously in T-cell receptor (TCR)-transgenic mice devoid of endogenous TCR-alpha and TCR-beta chains. Inhibition of RAGE markedly decreased infiltration of the CNS by immune and inflammatory cells. Transgenic mice with targeted overexpression of dominant-negative RAGE in CD4+ T cells were resistant to MBP-induced EAE. These data reinforce the importance of RAGE-ligand interactions in modulating properties of CD4+ T cells that infiltrate the CNS.

The Kuiper belt region of the solar system, stretching from 30 to at least 50 AU, contains Pluto-Charon, some ~105 Kuiper belt objects (KBOs) larger than 100 km in diameter, and myriad smaller bodies produced by collisions among KBOs (Farinella, Davis, & Stern, published in 2000). The most notable physical attribute of the KBOs discovered to date is their reflectance color diversity, ranging from gray (i.e., neutral) to very red (Tegler & Romanishin, published in 2000). I report here evidence for a statistical correlation between the colors of KBOs and the mean random impact speed that these objects experience, lending evidence to suggestions some years ago by modelers (Jewitt & Luu, published in 1996) that a competition between collisional resurfacing and radiation reddening may contribute to the color diversity of KBOs.

We describe the design, scientific objectives, and radiometric performance and calibration results of the Rosetta/ALICE instrument. ALICE is a lightweight (3.0 kg), low-power (4 W), low-cost imaging spectrometer optimized for cometary ultraviolet spectroscopy. Funded by NASA (with hardware contributions from CNES, France), ALICE will fly in 2003 on the ESA Rosetta Orbiter to characterize the cometary nucleus, coma, and nucleus/coma coupling of the Rosetta mission prime target comet 46P/Wirtanen. ALICE will also make observations of two asteroid flyby targets and of the Moon and Mars during the cruise portions of the Rosetta mission. It will obtain spatially-resolved, far-UV spectra of Wirtanen's nucleus and coma in the 700-2050A passband with a spectral resolution of 8-12A for extended sources that fill the entrance slit's 0.05 degree(s) x 6 degree(s) field-of-view. An improved derivative of the Rosetta/ALICE is also the UV spectrometer aboard the PERSI remote sensing suite proposed for the Pluto Kuiper Belt mission. ALICE uses modern technology to achieve its low mass and low power design specifications. It employs an off-axis telescope feeding a 0.15-m normal incidence Rowland circle spectrograph with a concave (toroidal) holographic reflection grating. The imaging microchannel plate (MCP) detector utilizes dual solar-blind opaque photocathodes of KBr and CsI deposited on a cylindrically-curved (7.5-cm radius) MCP Z-stack, and a matching 2-D cylindrically-curved double delay-line readout array with a 1024 x 32 pixel array format. Three data taking modes exist: (i) histogram image mode for 2-D images, (ii) pixel list mode with periodic time fiducials for temporal studies, and (iii) count rate mode for broadband photometric studies. Optical and radiometric sensitivity performance results based on integrated system level tests of the ALICE flight model are presented and discussed.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Introduction A. Stern The frontier universe: at the edge of night A. Stern Part I. Revealing A Universe: Mapmaker, mapmaker make me a map: probing the universe's large scale structure John Huchra Looking back in time: searching for the highest redshift galaxies Esther Hu COBE probes the cosmic microwave background John Mather Computational adventures in large scale structure Nick Gnedin Part II. Denizens of the Deep: The discovery of massive black holes Doug Richstone Gamma ray bursters revealed Bohdan Paczynski Galaxy clusters, cathedrals, and the fate of the universe Megan Donahue Courier new, courier: dark matter and the discovery of galactic halos Jerry Ostriker Galaxy hunting: discovering low surface brightness galaxies Gregory Botham.

The Oort cloud1 of comets was formed by the ejection of icy planetesimals from the region of giant planets—Jupiter, Saturn, Uranus and Neptune—during their formation2. Dynamical simulations3,4 have previously shown that comets reach the Oort cloud only after being perturbed into eccentric orbits that result in close encounters with the giant planets, which then eject them to distant orbits about 104 to 105 AU from the Sun (1 AU is the average Earth–Sun distance). All of the models constructed until now simulate formation of the Oort cloud using only gravitational effects; these include the influence of the Sun, the planets and external perturbers such as passing stars and Galactic tides. Here we show that physical collisions between comets and small debris play a fundamental and hitherto unexplored role throughout most of the ejection process. For standard models of the protosolar nebula (starting with a minimum-mass nebula) we find that collisional evolution of comets is so severe that their erosional lifetimes are much shorter than the timescale for dynamical ejection. It therefore appears that collisions will prevent most comets escaping from most locations in the region of the giant planets until the disk mass there declines sufficiently that the dynamical ejection timescale is shorter than the collisional lifetime. One consequence is that the total mass of comets in the Oort cloud may be less than currently believed.

New astronomical and laboratory data show that the abundances of the two dominant ices, nitrogen and methane, on the surfaces of the Solar System's two largest dwarf planets are surprisingly similar — raising fresh questions.

We have developed and successfully flight-tested on 14 different airborne missions the hardware and techniques for routinely conducting valuable astronomical and aeronomical observations from high-performance, two-seater military-type aircraft. The SWUIS-A (Southwest Universal Imaging System - Airborne) system consists of an image-intensified CCD camera with broad band response from the near-UV to the near IR, high-quality foreoptics, a miniaturized video recorder, an aircraft-to-camera power and telemetry interface with associated camera controls, and associated cables, filters, and other minor equipment. SWUIS-A's suite of high-quality foreoptics gives it selectable, variable focal length/variable field-of-view capabilities. The SWUIS-A camera frames at 60 Hz video rates, which is a key requirement for both jitter compensation and high time resolution (useful for occultation, lightning, and auroral studies). Broadband SWUIS-A image coadds can exceed a limiting magnitude of V = 10.5 in

We extend previous results showing that the surfaces of Edgeworth-Kuiper Belt objects are not primordial and have been moderately to heavily reworked by collisions. Objects smaller than about $r = 2.5$ km have collisional disruption lifetimes less than 3.5 Gyr in the present-day collisional environment and have been heavily damaged in their interiors by large collisions. In the 30--50 AU region, impacts of 1 km radius comets onto individual 100 km radius objects occur on $7\times10^7$--$4\times10^8$ yr timescales, cratering the surfaces of the larger objects with $\sim$8--54 craters 6 km in diameter over 3.5 Gyr. Collision time scales for impacts of 4 meter radius projectiles onto 1 km radius comets range from 3--5 $ \times 10^7$ yr. The cumulative fraction of the surface area of 1 and 100 km radius objects cratered by projectiles with radii larger than 4 m ranges from a few to a few tens percent over 3.5 Gyr. The flux of EKO projectiles onto Pluto and Charon is also calculated and is found to be $\sim$3--5 times that of previous estimates. Our impact model is also applied to Centaur objects in the 5--30 AU region. We find the collisional/cratering histories of Centaurs are dominated by the time spent in the Edgeworth-Kuiper Belt rather than the time spent on planet-crossing orbits. Hence, the predominant surface activity of Centaur objects like Chiron is almost certainly not impact-induced., 17 pages, 8 figures. Icarus, 2000, in press

I would like to clarify several points in the News of the Week story (26 September, p. [1754][1]) by A. Lawler, “Rising costs could delay NASA's next mission to Mars and future launches.” When the National Research Council's Planetary Science Decadal Survey recommended the Mars Science Laboratory (MSL) mission for priority funding, it assigned a cost level of $650 million. This value, rather than $1.4 billion, is the true metric for seeing the deep damage that MSL's profligately overrunning cost—now likely to top $2.1 billion—has inflicted on NASA's Mars and wider planetary science budget. Also, the story focused its overrun discussion on instrument costs. Although certainly part of the problem, instrument cost increases have been considerably smaller than overruns in the rest of MSL's budget, which was severely mismatched to the project's complexity from its inception. This mismatch sowed the most fundamental seeds of MSL's cost problems. The article's end quote described NASA's Mars Sample Return (MSR) mission plan as “smoke and mirrors.” Disappointingly, MSR is becoming a mirage in the wake of MSL and other budget damage caused by numerous substantial Science Mission Directorate (SMD) cost overruns accepted in recent months. However, as evidenced by both internal NASA and external Office of Management and Budget scrutiny in 2007, NASA's MSR plan in the President's Fiscal Year 2009 budget did fit in SMD's future budget envelope. It could well have launched near 2020, had a strong emphasis on cost control been sustained as a priority. Finally, there was no mention that a NASA independent review team found numerous development issues that called MSL's 2009 launch date into serious doubt almost a year ago. Nor did it describe that scenarios for dealing with MSL without causing such deep budgetary damage elsewhere were proposed by SMD but rejected at higher levels in early 2008. That, and the concurrent, forced disbanding of the MSL independent review team, precipitated my resignation as SMD Associate Administrator. [1]: /lookup/doi/10.1126/science.321.5897.1754

Direct measurements of the abundance of argon in the lunar atmosphere were made in 1973 by instruments placed on the Moon during the Apollo 17 mission, but the total daytime abundance is unknown due to instrument saturation effects; thus, until we are able to return to the Moon for improved direct measurements, we must use remote sensing to establish the daytime abundance. In this paper, we present a complete analysis of the potential for measuring argon in the lunar atmosphere via emission-line or absorption-line observations. We come to the surprising conclusion that the lower limit established by the in situ lunar argon measurements implies that any absorption-line measurement of argon in the lower, dayside lunar atmosphere requires analysis in the optically-thick regime. In light of this result, we present the results of our EUVS sounding rocket observations of the lunar occultation of Spica, which provide a new upper limit on the abundance of argon in the daytime lunar atmosphere. We also re-analyze a recently reported weak detection of lunar atmospheric Ar I 1048 in emission by the ORFEUS satellite, and show that those data are inconsistent with the emission being due to argon over a wide range of temperatures. This result is primarily due to our use of a more complete curve of growth analysis, and improved values for the argon fluorescent emission rates from radiation and solar wind interactions. We find that the detection reported by ORFEUS would imply an argon surface density significantly greater than the total surface density of the lunar atmosphere for argon accommodated to typical daytime surface temperatures (~400 K), and also is inconsistent with a high-density transient event. We conclude that the reported argon detection is untenable., 5 pages, 2 figures

We present an overview of the expected performance and science goals of the cosmic origins spectrograph (COS), a fourth generation instrument to be installed aborad the Hubble Space Telescope (HST) during the fourth HST servicing mission scheduled for late 2002. COS is a UV spectrograph optimized for observing faint point sources with moderate spectral resolution. The instrument has two channels: a far- UV channel that is sensitive in the 1150-1775 angstrom wavelength range and a near-UV channel that operates between 1750-3200 angstrom. The COS science team program concentrates on QSO absorption line systems and the IGM, dynamics of the ISM in galaxies and galaxy halos, UV extinction in the Milky Way, horizontal-branch stars in globular clusters, and volatile gases in the atmospheres of solar system bodies.

The challenge of space flight in NASA’s future is to enable smaller, more frequent and intensive space exploration at much lower total cost without substantially decreasing mission reliability, capability, or the scientific return on investment. The most effective way to achieve this goal is to build intelligent capabilities into the spacecraft themselves. Our technological vision for meeting the challenge of returning quality science through limited communication bandwidth will actually put scientists in a more direct link with the spacecraft than they have enjoyed to date. Technologies such as pattern recognition and machine learning can place a part of the scientist’s awareness onboard the spacecraft to prioritize downlink or to autonomously trigger time-critical follow-up observations—particularly important in flyby missions—without ground interaction. Onboard knowledge discovery methods can be used to include candidate discoveries in each downlink for scientists’ scrutiny. Such capabilities will allo...

The New Horizons Mission to Pluto-Charon and the Kuiper Belt is under development for launch in 2006. The experiment complement of eight sensors addresses fundamental issues of density, composition, albedo, geology, and atmospheric state, chemistry, and escape.

The Ball Aerospace & Technologies Corporation and Southwest Research Institute have built a three mirror anastigmat telescope as a proof-of-concept, working model of the visible camera system for the highly integrated Pluto payload system (HIPPS) intended for use on the Pluto Express mission. This instrument is unique due to its small size, light weight (less than 2.5 kg) and bolt together design. The all aluminum construction allows the unit to operate over a wide temperature range. The system was designed to have a 5.8 by 0.2 degree field of view, 650 mm effective focal length, 75 mm diameter entrance pupil and a 26 micrometer spot size. The initial version of this telescope utilized diamond turned aluminum mirrors due to cost and schedule limitations. The scattering and imaging properties of this telescope were evaluated. A baffle system was designed and installed to reduce stray light in the system. To improve system performance, the mirrors were resurfaced with electroless nickel, diamond turned and post polished. The stray light performance of the system before and after resurfacing the optics is discussed. Future performance testing plans for this system are presented.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We describe the design concept for the highly integrated Pluto payload system (HIPPS): a highly integrated, low-cost, light-weight, low-power instrument payload designed to fly aboard the proposed NASA Pluto flyby spacecraft destined for the Pluto/Charon system. The HIPPS payload is designed to accomplish all of the Pluto flyby prime (IA) science objectives, except radio science, set forth by NASA's Outer Planets Science Working Group (OPSWG) and the Pluto Express Science Definition Team (SDT). HIPPS contains a complement of three instrument components within one common infrastructure; these are: (1) a visible/near UV CCD imaging camera; (2) an infrared spectrograph; and (3) an ultraviolet spectrograph. A detailed description of each instrument is presented along with how they will meet the IA science requirements.

We report on the status of modifications to an existing extreme ultraviolet (EUV) telescope/spectrograph sounding rocket payload for planetary observations in the 800 - 1200 A wavelength band. The instrument is composed of an existing Wolter Type 2 grazing incidence telescope, a newly built 0.4-m normal incidence Rowland Circle spectrograph, and an open-structure resistive-anode microchannel plate detector. The modified payload has successfully completed three NASA sounding rocket flights within 1994-1995. Future flights are anticipated for additional studies of planetary and cometary atmospheres and interstellar absorption. A detailed description of the payload, along with the performance characteristics of the integrated instrument are presented. In addition, some preliminary flight results from the above three missions are also presented.

A spectrum of comet Austin (1988 c(1)) has been obtained from 910 to 1180 A. Three bright emission lines were detected, including a forbidden oxygen line (1128 A), which are attributable to radiative pumping of neutral oxygen by solar Lyman beta. The relative strengths of the observed features should prove to be a useful diagnostic of the physical conditions and radiation fields in cometary comae. In addition, the absence of strong spectral features from highly volatile species such as He, Ar, or N(2) can be used to place constraints on the thermal environment under which the comet was formed and has been processed.

The Working Group was formed at the request of the Board of DivisionIII and approved by the IAU Executive committee in March 2004. This was in recognition of the fact that discoveries in the Trans Neptunian region were repeatedly raising the question of “what is a planet”. The task of the WG was to investigate the options available and give indications of the level of support and opposition for each if more than one option was emerging.

On May 15–17, 1995, three Rocky Mountain research institutions hosted a conference to discuss the scientific basis, technological options, and programmatic implications of a large-scale effort to find and study Earth-like planets outside the Solar System. The workshop attracted scientists, engineers, space agency administrators, and the public media to discuss and debate the most promising technological options and opportunities. Major programs and proposals to search for and study exo-planets were presented and discussed. This special issue of the Journal of Geophysical Research contains several of the most interesting poster papers, which were extended to greater length by the authors and submitted for peer review.