A5021224134- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Planetary Science and Exploration
- Astronomical Observations and Instrumentation
- Astronomy and Astrophysical Research
- Isotope Analysis in Ecology
- Astrophysics and Star Formation Studies
- Solar and Space Plasma Dynamics
- Space Exploration and Technology
- Atmospheric Ozone and Climate
- Historical Astronomy and Related Studies
- Gamma-ray bursts and supernovae
- Geomagnetism and Paleomagnetism Studies
- History and Developments in Astronomy
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- Geology and Paleoclimatology Research
- Astrophysical Phenomena and Observations
- Ionosphere and magnetosphere dynamics
- Scientific Research and Discoveries
- Geological and Geochemical Analysis
- Spacecraft and Cryogenic Technologies
- Astronomical and nuclear sciences
- Inertial Sensor and Navigation
- Methane Hydrates and Related Phenomena
Lowell Observatory
2013-2022
Jet Propulsion Laboratory
2011
Association of Universities For Research In Astronomy
2002-2005
Kitt Peak National Observatory
2002-2005
U.S. National Science Foundation
2002-2005
Cerro Tololo Inter-American Observatory
2005
University of Canterbury
1993
Cornell University
1972-1976
With the NEOWISE portion of Wide-field Infrared Survey Explorer (WISE) project, we have carried out a highly uniform survey near-Earth object (NEO) population at thermal infrared wavelengths ranging from 3 to 22 μm, allowing us refine estimates their numbers, sizes, and albedos. The detected NEOs same way whether they were previously known or not, subject availability ground-based follow-up observations, resulting in discovery more than 130 new NEOs. survey's sensitivity, observing cadence,...
We report on a sub-stellar companion search utilizing interferometric fringe-tracking astrometry acquired with Fine Guidance Sensor 3 (FGS 3) the Hubble Space Telescope. Our targets were Proxima Centauri and Barnard's Star. obtain absolute parallax values for Cen pi_{abs} = 0.7687 arcsecond Star 0.5454 arcsecond. Once low-amplitude instrumental systematic errors are identified removed, our detection sensitivity is less than or equal to one Jupiter mass periods longer 60 days Cen. Between...
We present an absolute parallax and relative proper motion for the fundamental distance scale calibrator δ Cep. obtain these with astrometric data from FGS 3, a white-light interferometer on Hubble Space Telescope (HST). Utilizing spectrophotometric estimates of parallaxes our reference stars constraining Cep star HD 213307 to belong same association (Cep OB6), we find πabs = 3.66 ± 0.15 mas. The larger than typical residuals nearby are found satisfy Keplerian P 1.07 0.02 yr, perturbation...
The Deep Ecliptic Survey (DES)—a search optimized for the discovery of Kuiper belt objects (KBOs) with Blanco and Mayall 4 m telescopes at Cerro Tololo Inter-American Observatory Kitt Peak National Observatory—has covered 550 deg2 from its inception in 1998 through end 2003. This survey has a mean 50% sensitivity VR magnitude 22.5. We report here discoveries 320 designated KBOs Centaurs period 2000 March 2003 December describe improvements to our recovery procedures. Our data products needed...
We present initial results from time-series imaging at infrared wavelengths of 0.9 deg2 in the Orion Nebula Cluster (ONC). During Fall 2009 we obtained 81 epochs Spitzer 3.6 and 4.5 μm data over 40 consecutive days. extracted light curves with ∼3% photometric accuracy for ∼2000 ONC members ranging several solar masses down to well below hydrogen-burning mass limit. For many stars, also have photometry optical (Ic) and/or near-infrared (JKs) wavelengths. Our set can be mined determine stellar...
We present a Mass-Luminosity Relation (MLR) for red dwarfs spanning range of masses from 0.62 Msun to the end stellar main sequence at 0.08 Msun. The relation is based on 47 stars which dynamical have been determined, primarily using astrometric data Fine Guidance Sensors (FGS) 3 and 1r, white-light interferometers Hubble Space Telescope (HST), radial velocity McDonald Observatory. For our HST/FGS sample 15 binaries component mass errors 0.4% 4.0% with median error 1.8%. With these other...
The empirical mass-luminosity relation at M is presented for stars with masses 0.08-0.20 M☉ based upon new observations made Fine Guidance Sensor 3 on the Hubble Space Telescope. targets are nearby, red dwarf multiple systems in which magnitude differences typically measured to ±0.1 mag or better. values generated using best available parallaxes and also accurate mag, because errors dominant error source. In several cases this first time observed sub-arcsecond multiples have been resolved...
As part of our ongoing Deep Ecliptic Survey (DES) the Kuiper belt, we report on occupation 1 : (Trojan), 4 3, 3 2, 7 4, 2 1, and 5 Neptunian mean motion resonances (MMRs). The previously unrecognized MMRs is not easily understood within standard model resonance sweeping by a migratory Neptune over an initially dynamically cold belt. Among all resonant belt objects (KBOs), three observed members MMR discovered DES possess largest semimajor axes (a ≈ 55.4 AU), highest eccentricities (e 0.4),...
We report the detections of low-mass companions to five M and L dwarfs within 10 pc Sun using Hubble Space Telescope (HST) Near-Infrared Camera Multi-Object Spectrometer (NICMOS). Follow-up observations HST Advanced for Surveys (ACS) Fine Guidance Sensor 1r (FGS1r) confirm our NICMOS discoveries L4.5 dwarf GJ 1001B (LHS 102B) M5 LHS 224, respectively. Images obtained with Astrophysical Research Consortium 3.5 m telescope at Apache Point Observatory verify discovery a companion M3 G239-25....
Combining stellar occultation observations probing Pluto's atmosphere from 1988 to 2013, and models of energy balance between surface atmosphere, we find the preferred are consistent with Pluto retaining a collisional throughout its 248-year orbit. The results show an increasing atmospheric pressure time in current epoch, trend present only high thermal inertia permanent N2 ice cap at north rotational pole.
We have observed Proxima Centauri and Barnard's Star with Hubble Space Telescope Fine Guidance Sensor 3. exhibits small-amplitude, periodic photometric variations. Once several sources of systematic error are corrected, we obtain 2 milli-magnitude internal precision. identify two distinct behavior modes over the past four years: higher amplitude, longer period; smaller shorter period. Within errors one period (P ~ 83d) is twice other. shows very weak evidence for periodicity on a timescale...
Using data from the Deep Ecliptic Survey (DES), we investigate inclination distributions of objects in Kuiper Belt. We present a derivation for observational bias removal and use this procedure to generate unbiased Belt (KBOs) different DES dynamical classes, with respect plane. Consistent previous results, find that distribution all KBOs is well fit by sum two Gaussians, or Gaussian plus generalized Lorentzian, multiplied sin i. Approximately 80% are high-inclination grouping. Classical...
Context. Pluto's tenuous nitrogen (N2) atmosphere undergoes strong seasonal effects due to high obliquity and orbital eccentricity, has been recently (July 2015) observed by the New Horizons spacecraft. Goals are (i) construct a well calibrated record of evolution surface pressure on Pluto (ii) constrain structure lower using central flash in 2015. Method: eleven stellar occultations between 2002 2016 used retrieve atmospheric profiles (density, pressure, temperature) $\sim$5 km $\sim$380...
The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, are primitive objects preserving information about Solar System formation. New Horizons spacecraft flew past one these objects, the 36 km long contact binary (486958) Arrokoth (2014 MU69), January 2019. Images from flyby show that has no detectable rings, and satellites (larger than 180 meters diameter) within radius 8000 km, lightly-cratered smooth surface with complex geological features, unlike...
We report here initial results of the Deep Ecliptic Survey, an ongoing new search for Kuiper belt objects (KBOs) and Centaurs using 8K × Mosaic CCD array on 4 m Mayall Telescope at Kitt Peak National Observatory. Within interval covered in this paper, useful observations were obtained during seven nights 1998 October November, 1999 April, 2000 February. used a novel technique to efficiently find determine positions moving objects. Sixty-nine KBOs with apparent magnitudes between 20.6...
We report on Keck Interferometer observations of the double-lined binary (B) component quadruple pre-main sequence (PMS) system HD 98800. With these interferometric combined with astrometric measurements made by Hubble Space Telescope Fine Guidance Sensors (FGS), and published radial velocity we have estimated preliminary visual physical orbits 98800 B subsystem. Our orbit model calls for an inclination 66.8 $\pm$ 3.2 deg, allows us to infer masses luminosities individual components. In...