相关论文: The propeller and the frog

The Doppler shift of a radio signal is caused by the relative motion between the transmitter and receiver. The change in frequency of the signal over time is called drift rate. In the studies of radio SETI (Search for Extraterrestrial…

In addition to its long-term constancy, the Pioneer (spacecraft) anomaly appears to only exist for bodies whose mass is less than that of: planets, moons, comets, and heavy asteroids of known mass. Assuming the observational evidence is…

New long-term Very Long Baseline Array observations of the well-known jet in the M87 radio galaxy at 43 GHz show that the jet experiences a sideways shift with an approximately 8-10 yr quasi-periodicity. Such jet wobbling can be indicative…

Since 2013, dense and narrow rings are known around the small Centaur object Chariklo and the dwarf planet Haumea. Dense material has also been detected around the Centaur Chiron, although its nature is debated. This is the first time ever…

Motivated by the large number of extrasolar planetary systems that are near mean motion resonances, this paper explores a related type of dynamical behavior known as "nodding". Here, the resonance angle of a planetary system executes…

We follow the approach used by Davies and Pringle (1981) and discuss the trans-sonic substage of the propeller regime. This substage is intermediate between the supersonic and subsonic propeller substages. In the trans-sonic regime an…

While numerous planetary and asteroid satellites show evidence for non-trivial rotation states, none are as emblematic as Hyperion, which has long been held as the most striking example of chaotic spin-orbit evolution in the Solar System.…

Janus and Epimetheus are famously known for their distinctive horseshoe-shaped orbits resulting from a 1:1 orbital resonance. Every four years these two satellites swap their orbits by a few tens of kilometers as a result of their close…

Images obtained by the Cassini spacecraft of the region just beyond Saturn's main rings reveal a previously unreported narrow and dusty ringlet that has dynamical connections with both Saturn's small satellite Prometheus and the F ring. The…

We address the occurrence of narrow planetary rings under the interaction with shepherds. Our approach is based on a Hamiltonian framework of non-interacting particles where open motion (escape) takes place, and includes the quasi-periodic…

Plutinos are Kuiper-belt objects that share the 3:2 Neptune resonance with Pluto. The long-term stability of Plutino orbits depends on their eccentricity. Plutinos with eccentricities close to Pluto (fractional eccentricity difference…

The activity of at least one repeating Fast Radio Burst (FRB) source is periodically modulated. If this modulation is the result of precession of the rotation axis and throat of an accretion disc around a black hole, driven by a companion…

Irregular moons are a class of satellite found orbiting all of the Solar System's giant planets: as their orbits don't match those of their planets, they are theorised to have formed elsewhere in the Solar System and were subsequently…

Estimates of the size of the feeding zone of the planet Proxima Centauri c have been made at initial orbital eccentricities of planetesimals equal to 0.02 or 0.15. The research is based on the results of modeling of the evolution of…

The self-propelled, longstanding rotation of the polymer tubing containing camphor continuing for dozens of hours is reported. The rotator is driven by the solutocapillary Marangoni flows owing to the dissolution of camphor. The…

Close-by planets may excite various kinds of oscillations in their host stars through their time-varying tidal potential. Magnetostrophic oscillations with a frequency much smaller than the stellar rotation frequency have recently been…

Efforts are made to understand the timing behaviors (e.g., the jumps of the projected pulsar semimajor axis in the periastron passages) observed via 13-year timing for PSR B1259-63. In the first, planet-like objects are suggested to orbit…

Whenever a freely spinning body is found in a complex rotational state, this means that either the body is a recent victim of an impact or a tidal interaction, or is a fragment of a recently disrupted progenitor. Another factor (relevant…

The quasi-periodic feature of 1-10 years exhibited in pulsar timing noise has not been well understood since 1980. The recently demonstrated correlation between timing noise and variation of pulse profile motivates us to further investigate…

A diversity of resonance configurations may be formed under different migration of two giant planets. And the researchers show that the HD 128311 and HD 73526 planetary systems are involved in a 2:1 mean motion resonance but not in apsidal…