Related papers: High speed escape from a circular orbit
A new control algorithm based on the partial control method has been developed. The general situation we are considering is an orbit starting in a certain phase space region Q having a chaotic transient behavior affected by noise, so that…
Fast microjets can emerge out of liquid pools from the rebounding of drop-impact craters, or when a bubble bursts at it surface. The fastest jets are the narrowest and are a source of aerosols both from the ocean and a glass of champagne,…
Many rocky exoplanets are heavier and larger than Earth, so-called "Super-Earths". Some of these may be habitable, and a few may be inhabited by Super-Earthlings. Due to the higher surface gravity on these worlds, space-flight is much more…
We study three processes that eject hypervelocity (>10^3 km/s) stars from the Galactic center: (i) close encounters of two single stars; (ii) tidal breakup of binary stars by the central black hole, as originally proposed by Hills; and…
The origin of high velocity stars observed in the halo of our Galaxy is still unclear. In this work we test the hypothesis, raised by results of recent high precision $N$-body simulations, of strong acceleration of stars belonging to a…
Hypervelocity stars are those that have speeds exceeding the escape speed and are hence unbound from the Milky Way. We investigate a sample of low-mass hypervelocity candidates obtained using data from the high-precision SDSS Stripe 82…
Recent studies on hypervelocity stars (HVSs) have generated a need to understand the high velocity limits of binary systems. If runaway binary systems with high movement speeds well in excess of 200km/s were to exist, it would have…
Rotating black holes are the most powerful source of energy in the known universe, and are the cause of some of the most spectacular and extreme astronomical phenomena. The goal of this article is to analyze in simple terms the physics of…
On the basis of a recent cosmological model, the puzzle of galactic rotational velocities at their edges is explained without invoking dark matter. A rationale for the existence of structures like galaxies and superclusters is also…
Large scale manned space flight within the solar system is still confronted with the solution of two problems: 1. A propulsion system to transport large payloads with short transit times between different planetary orbits. 2. A cost…
We report the detection of five high-velocity stars in the core of the globular cluster NGC 2808. The stars lie on the the red giant branch and show total velocities between 40 and 45 km/s. For a core velocity dispersion sigma_c = 13.4…
In recent years, evidence has been obtained that in the outer region of the Solar System (in the inner part of the Oort cloud), at a distance $\sim300-700$ AU from the Sun, there may be a captured planet or a primordial black hole. In this…
Achieving relativistic flight to enable extrasolar exploration is one of the dreams of humanity and the long term goal of our NASA Starlight program. We derive a fully relativistic solution for the motion of a spacecraft propelled by…
We discuss the existence and stability of circular orbits of a relativistic point particle moving in a central force field. The stability condition is somewhat more restrictive in Special Relativity. In the particular case of attractive…
We show existence and give an implicit formula for the escape rate of the n-centre problem of celestial mechanics for high energies. Furthermore we give precise computable estimates of this rate. This exponential decay rate plays an…
The discovery of hypervelocity stars (HVS) leaving our galaxy with speeds of nearly $10^{3}$ km s$^{-1}$ has provided strong evidence towards the existence of a massive compact object at the galaxy's center. HVS ejected via the disruption…
We model the fastest moving (v_tot > 300 km/s) local (D < 3 kpc) halo stars using cosmological simulations and 6-dimensional Gaia data. Our approach is to use our knowledge of the assembly history and phase-space distribution of halo stars…
The abnormally intense radiation due to the uniform rotation of electron around the equatorial plane of a dielectric sphere is obtained. It takes place when the sphere surface is at a specific distance from the electron orbit and when the…
In similar-sized planetary collisions, a significant part of the impactor often misses the target and continues downrange. We follow the dynamical evolution of "runners" from giant impacts to determine their ultimate fate. Surprisingly,…
The existence of hyperbolic orbits is proved for a class of restricted three-body problems with a fixed energy by taking limit for a sequence of periodic solutions which are obtained by variational methods.