65 research outputs found
New Horizons Successful Completes the Historic First Flyby of Pluto and Its Moons
On July 14, 2015, after a 9.5 year trek across the solar system, NASA's New Horizons spacecraft flew by the dwarf planet Pluto and its system of moons, taking imagery, spectra and in-situ particle data. Data from New Horizons will address numerous outstanding questions on the geology and composition of Pluto and Charon, plus measurements of Pluto's atmosphere, and provide revised understanding of the formation and evolution of Pluto and Charon and its smaller moons. This data set is an invaluable glimpse into the outer Third Zone of the solar system. Data from the intense July 14th fly-by sequence will be downlinked to Earth over a period of 16 months, the duration set by the large data set (over 60 GBits) and the limited transmitted bandwidth rates (approx. 1-2 kbps) and sharing the three 70 m DSN assets with our missions. The small fraction (approx. 1%) of data downlinked during the early phase of the flyby has already revealed Pluto and Charon to be very different worlds, with increasing and dynamic complexity
Pluto Revealed: First Results from the Historic 1st Fly-By Space Mission.
On July 14, 2015, after a 9.5 year trek across the solar system, NASAs New Horizons spacecraft successfully flew by the dwarf planet Pluto and its system of moons, taking imagery, spectra and in-situ particle data. In this internet-information age, this historic first fly-by was shared across planet Earth, everyone witnessing first-hand the transformation of distant point of lights into real worlds. The New Horizons dataset has become an invaluable first glimpse into the outer Third Zone of the Solar System. Pluto has revealed itself to be a complex, beautiful place, with a variety of geophysical and surface-atmosphere interactions. Charon has been unmasked; its surface features implying a complicated, enigmatic history. The smaller moons, origins still unknown, are uniquely different in their own right. This presentation summarizes NASAs New Horizons mission and its early science results, and touches on the future of further exploring the outer Third Zone
Configurable Aperture Space Telescope
In December 2014, we were awarded Center Innovation Fund to evaluate an optical and mechanical concept for a novel implementation of a segmented telescope based on modular, interconnected small sats (satlets). The concept is called CAST, a Configurable Aperture Space Telescope. With a current TRL is 2 we will aim to reach TLR 3 in Sept 2015 by demonstrating a 2x2 mirror system to validate our optical model and error budget, provide straw man mechanical architecture and structural damping analyses, and derive future satlet-based observatory performance requirements. CAST provides an alternative access to visible and/or UV wavelength space telescope with 1-meter or larger aperture for NASA SMD Astrophysics and Planetary Science community after the retirement of HS
Detection of Ocean Glint and Ozone Absorption Using LCROSS Earth Observations
The Lunar CRater Observation and Sensing Satellite (LCROSS) observed the
distant Earth on three occasions in 2009. These data span a range of phase
angles, including a rare crescent phase view. For each epoch, the satellite
acquired near-infrared and mid-infrared full-disk images, and partial-disk
spectra at 0.26-0.65 microns (R~500) and 1.17-2.48 microns (R~50). Spectra show
strong absorption features due to water vapor and ozone, which is a
biosignature gas. We perform a significant recalibration of the UV-visible
spectra and provide the first comparison of high-resolution visible Earth
spectra to the NASA Astrobiology Institute's Virtual Planetary Laboratory
three-dimensional spectral Earth model. We find good agreement with the
observations, reproducing the absolute brightness and dynamic range at all
wavelengths for all observation epochs, thus validating the model to within the
~10% data calibration uncertainty. Data-model comparisons reveal a strong ocean
glint signature in the crescent phase dataset, which is well matched by our
model predictions throughout the observed wavelength range. This provides the
first observational test of a technique that could be used to determine
exoplanet habitability from disk-integrated observations at visible and
near-infrared wavelengths, where the glint signal is strongest. We examine the
detection of the ozone 255 nm Hartley and 400-700 nm Chappuis bands. While the
Hartley band is the strongest ozone feature in Earth's spectrum, false
positives for its detection could exist. Finally, we discuss the implications
of these findings for future exoplanet characterization missions.Comment: Accepted to The Astrophysical Journal; recalibration data for LCROSS
VSP can be found at:
https://sites.google.com/site/tdrobinsonscience/science/moo
LCROSS: Volatiles and Exosphere Associated with a Permanently Shadowed Region in Cabeus
We discuss the volatile species in the LCROSS data set in addition to water that were observed by the LCROSS Shepherding Spacecraft before its own demise in the four minutes following the first impact by the Centaur. The stochastic nature of the temporal variations observed by the nadir-viewing near-infrared spectrometer combined with the diversity of the volatile species suggests that these species were in situ in the permanently shadowed crater and were released by a combination of the centaur impact and the resulting warming of the regolith by the impact and ejecta debris blanket. Adding to this intrigue are the pre-impact observations by the UVVisual spectrometer that reveal that the field-of-view into the permanently shadowed crater contains UV emission lines, The UV lines are clearly revealed once the descent of the shepherding spacecraft narrows the field-of-view of the UV-Vis spectrometer so as to exclude any surrounding bright terrain. Our suggestion is that this emission comes from tenuous gases, i.e., there appears to be a potential association between the cold, permanently shadowed region and an exosphere
Fifty Years of Exploring Pluto: from Telescopes to the New Horizons Mission
Pluto was discovered in 1930 at Lowell Observatory in the belated resumption of a wide-field photographic search originally be-gun at Percival Lowells direction prior to his death in 1916. Photometry in the 1950s established the rotation period of 6.4 hours and a color redder than the Sun, but the mass, density, size and albedo were unknown. Near-infrared photometry in 1976 indicated the presence of CH4 frost, suggestive of a relatively high surface albedo and a diameter comparable to the Moon. The large satellite Charon was discovered in 1978, followed by an epoch of mutual transits and occultations of Pluto and Charon from 1985 to 1990, as viewed from Earth. These events resulted in reliable sizes and masses of the two bodies, as well as the orbit of Charon. The mutual events also demonstrated that Pluto and Charon are in locked synchronous rotation and revolution, a configuration unique among the planets. The atmosphere of Pluto was discovered in 1988 from a stellar occultation observed from the Kuiper Airborne Observatory and ground stations, with indications of a haze layer (or a temperature inversion) in the lower atmosphere. Sub-sequent stellar occultations showed that the extent of the atmosphere is variable on a timescale of a few years. The spectroscopic detection of N2 and CO ice in 1993 demonstrated that the atmosphere must be primarily composed of N2, with CH4 and CO as minor components; the spectroscopic detection of gaseous CH4 was reported in 1994
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