相关论文: The rings of Neptune

Neptune's incomplete ring arcs have been stable since their discovery in 1984 by stellar occultation. Although these structures should be destroyed within a few months through differential Keplerian motion, imaging data over the past couple…

Voyager 2 images confirmed the presence of ring arcs around Neptune. These structures need a confinement mechanism to constrain their spreading due to collisions, dissipative forces, and differential keplerian motion. Here we report the…

The arcs of Neptune - Fraternit\'e, Egalit\'e, Libert\'e, and Courage - are four incomplete rings immersed in the Adams ring. A recent confinement model for the arcs proposes that the structures are azimuthally confined by four co-orbital…

The ring system and small satellites of Neptune were discovered during Voyager 2 flyby in 1989 (Smith et al.1989). In this work we analyse the diffusion maps which can give an overview of the system. As a result we found the width of…

We surveyed 1.75 square degrees of sky near Neptune to an R-band 50% detection efficiency of 25.8 mags (corresponding to radii of about 17 km for an assumed albedo of 0.04). We discovered one new outer satellite, Psamathe (S/2003 N1), about…

By distinguishing the main arc Fraternite from the minor arcs Egalite (2,1), Liberte, Courage, the restricted three-body system is extended to a non-conservative restricted four-body system with the central body Neptune S, the primary body…

According to recent works [Tsui PSS \textbf{55}, 237-242 (2007), \textbf{55}, 2042-2044 (2007)], the Neptune Adams ring main arc Fraternite is regarded as captured by the corotation elliptic resonance (CER) potential of Galatea. The minor…

By considering the finite mass of Fraternite, although small, it is shown that there are two time averaged stationary points in its neighborhood due to the reaction of the test body to the fields of Neptune, Galatea, and Fraternite. These…

Since 2013, observations of Neptune with small telescopes have resulted in several detections of long-lived bright atmospheric features that have also been observed by large telescopes such as Keck II or Hubble. The combination of both…

The Kuiper belt is a population of icy bodies beyond the orbit of Neptune. A particularly puzzling and up-to-now unexplained feature of the Kuiper belt is the so-called `kernel', a concentration of orbits with semimajor axes a~44 AU,…

We have used the Spitzer Space Telescope in February 2016 to obtain high cadence, high signal-to-noise, 17-hour duration light curves of Neptune at 3.6 and 4.5 $\mu$m. The light curve duration was chosen to correspond to the rotation period…

In addition to its suite of narrow dense rings, Uranus is surrounded by an extremely complex system of dusty rings that were most clearly seen by the Voyager spacecraft after it flew past the planet. A new analysis of the highest resolution…

We fit an isothermal oscillatory density model of Neptune's protoplanetary disk to the surviving regular satellites and its innermost ring and we determine the radial scale length of the disk, the equation of state and the central density…

The boundaries of the Uranian epsilon, alpha, and beta rings can be fitted by Keplerian ellipses. The pair of ellipses that outline a given ring share a common line of apsides. Apse alignment is surprising because the quadrupole moment of…

Mid-IR albedo values of Neptune are derived from Spitzer Space Telescope measurements reported by Stauffer et al. (2016). The method of this derivation is described and the results indicate that the geometric albedo was about 1% or less at…

Until now, rings have been detected in the Solar System exclusively around the four giant planets. Here we report the discovery of the first minor-body ring system around the Centaur object (10199) Chariklo, a body with equivalent radius…

NASA's Kepler mission identified over 4000 extrasolar planets that transit (cross in front of) their host stars. This sample has revealed detailed features in the demographics of planet sizes and orbital spacings. However, knowledge of…

The zeta ring is the innermost component of the Uranian ring system. It is of scientific interest because its morphology changed significantly between the Voyager 2 encounter in 1986 and subsequent Earth-based observations around 2007. It…

Certain regions of Saturn's rings exhibit periodic opacity variations with characteristic radial wavelengths of up to a few hundred meters that have been attributed to viscous overstabilities. The Visual and Infrared Mapping Spectrometer…

Observations of the November 1995 Sun crossing of the Saturn's ring-plane made with the 3.6m CFH telescope, using the UHAO adaptive optics system, are presented here. We report the detection of four arcs located in the vicinity of the F…