The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
I show that the size-distribution of small scattered-disk trans-neptunian objects when derived from the observed size-distribution of Jupiter Family comets (JFCs) and other observational constraints implies that a large percentage (94–97%) of newly arrived active comets within a range of 0.2–15.4km effective radius must physically disrupt, i.e., macroscopically disintegrate, within their median dynamical...
We examine the flux of bodies striking Pluto and Charon, and the nature of the crater populations that will form as a result of these impacts. Assuming impact speeds of 2km/s and an impact angle of 45°, a 1km impactor will form a 4.2km diameter transient crater on Pluto, and a ∼5.0km crater on Charon, as compared with 8–13km for several mid-sized saturnian satellites and 8–10km for the icy Galilean...
We use a one-dimensional adaptive-grid thermal evolution code to model Kuiper belt objects Charon, Orcus and Salacia and compare their measured bulk densities with those resulting from evolutionary calculations at the end of 4.6Gyr. Our model assumes an initial homogeneous composition of mixed ice and rock, and follows the multiphase flow of water through the porous rocky medium, consequent differentiation...
Evidence from stellar occultation datasets and Charon’s H2O–ice dominated surface composition has long suggested a lack of any current atmosphere around this satellite planet. However, impacts from both Kuiper Belt and Oort Cloud comets must from time to time import N2, CH4, and other cometary super-volatiles that can create temporary atmospheres around Charon. Here we estimate the frequency of such...
We report on Hubble Space Telescope (HST) observations of three Kuiper Belt Objects (KBOs), discovered in our dedicated ground-based search campaign, that are candidates for long-range observations from the New Horizons spacecraft: 2011 JY31, 2011 HZ102, and 2013 LU35. Astrometry with HST enables both current and future critical accuracy improvements for orbit precision, required for possible New...
The influx of interplanetary dust grains (IDPs) to the Pluto–Charon system is expected to drive several physical processes, including the formation of tenuous dusty rings and/or exospheres, the deposition of neutral material in Pluto’s atmosphere through ablation, the annealing of surface ices, and the exchange of ejecta between Pluto and its satellites. The characteristics of these physical mechanisms...
The clear angular separation of Pluto and Charon from ground-based telescopes has been enabled by improved technology, particularly adaptive optics systems. Near-infrared spectral data have revealed Charon’s surface to be rich in crystalline water ice and ammonia hydrates. In this work, we search for spectral differences across Charon’s surface with new near-infrared spectral data taken in the K-band...
In previous works we have studied the location of stable regions in the Pluto–Charon system. Among the findings, we discovered an island of stability, named sailboat island. One of the main goals of the New Horizons mission, launched in 2006, is to have a flyby close to the Pluto–Charon system in order to explore it. In the present work we analyze the relevance of the sailboat island for the New Horizons...
Aqueous organic solid formation from formaldehyde via the formose reaction and subsequent reactions is a possible candidate for the origin of complex primitive chondritic insoluble organic matter (IOM) and refractory carbon in comets. The rate of formation of organic solids from formaldehyde was studied as a function of temperature and time, with and without ammonia, in order to derive kinetic expressions...
Pluto and its satellites will be the most distant objects ever reconnoitered when NASA’s New Horizons spacecraft conducts its intensive flyby of this system in 2015. The size-frequency distribution (SFD) of craters on the surfaces in the Pluto system have long been expected to provide a useful measure of the size distribution of Kuiper Belt Objects (KBOs) down to much smaller size scales than presently...
From observations by the Hubble Space Telescope, Keck II Telescope, and Gemini North Telescope, we have determined the mutual orbit of the large transneptunian object (174567) Varda and its satellite Ilmarë. These two objects orbit one another in a highly inclined, circular or near-circular orbit with a period of 5.75days and a semimajor axis of 4810km. This orbit reveals the system mass to be (2...
The New Horizons spacecraft fly-through of the Pluto system in July 2015 will provide humanity’s first data for the crater populations on Pluto and its binary companion, Charon. In principle, these surfaces could be dated in an absolute sense, using the observed surface crater density (# craters/km2 larger than some threshold crater diameter D). Success, however, requires an understanding of both...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.