相关论文: Astronomical engineering: a strategy for modifying…

In around 5 gigayears our Sun will grow to a Red Giant and will swallow Earth. The plan is subdivided into two parts: We propose to construct some kind of parasol to shadow Earth. The position of the parasol will be the (inner) Lagrange…

From the numerous detected planets outside the Solar system, no terrestrial planet comparable to our Earth has been discovered so far. The search for an Exo-Earth is certainly a big challenge which may require the detections of planetary…

Recently, a 30-cm object was discovered to graze the Earth's atmosphere and shift into a Jupiter-crossing orbit. We use the related survey parameters to calibrate the total number of such objects. The number of objects that could have…

Mercury, due to its close location to the Sun, is surrounded by an environment whose conditions may be considered as "extreme" in the entire Solar System. Both solar wind and radiation are stronger with respect to other Solar System bodies,…

Changes in planetary obliquity, or axial tilt, influence the climates on Earth-like planets. In the solar system, the Earth's obliquity is stabilized due to interactions with our moon and the resulting {small amplitude variations…

The orbital evolution and stability of planetary systems with interaction from the belts is studied using the standard phase-plane analysis. In addition to the fixed point which corresponds to the Keplerian orbit, there are other fixed…

Jupiter and Saturn formed in a few million years (Haisch et al. 2001) from a gas-dominated protoplanetary disk, and were susceptible to gas-driven migration of their orbits on timescales of only ~100,000 years (Armitage 2007). Hydrodynamic…

Astrophysical evidence suggests that the Sun was born near 5 kpc from the Galactic center, within the corotation radius of the Galactic bar, around 6-7 kpc. This presents challenges for outward migration due to the Jacobi energy constraint,…

Earth will become uninhabitable within 2-3 Gyr as a result of the moving boundaries of the habitable zone caused by the increasing luminosity of the Sun. Predictions about the future of habitable conditions on Earth include a decline in…

Near Earth Asteroids have a possibility of impacting with the Earth and always have a thread on the Earth. This paper proposes a way of changing the trajectory of the asteroid to avoid the impaction. Solar sail evolving in a H-reversal…

Continuous habitability of a planet is a critical condition for advanced forms of life to appear, but it can be endangered by astronomical events such as stellar encounters. The purpose of this study is to analyze close stellar encounters…

Using an ensemble of N-body simulations, this paper considers the fate of the outer gas giants (Jupiter, Saturn, Uranus, and Neptune) after the Sun leaves the main sequence and completes its stellar evolution. Due to solar mass-loss --…

Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the planetary system as a whole governs a particular planet's…

This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Galaxy and the evolution of the Earth's orbital parameters in…

Several properties of the Solar System, including the wide radial spacing of the giant planets, can be explained if planets radially migrated by exchanging orbital energy and momentum with outer disk planetesimals. Neptune's…

The ability of a planet to maintain surface water, key to life as we know it, depends on solar and planetary energy. As a star ages, it delivers more energy to a planet. As a planet ages it produces less internal heat, which leads to…

During orbital migration of a giant extrasolar planet via ejection of planetesimals (Murray et al.~1998), inner mean motion resonances can be strong enough to cause planetesimals to graze or impact the star. We integrate numerically the…

Migration of trans-Neptunian objects to the Earth is considered. Due to the gravitational influence of large trans-Neptunian objects and mutual collisions, some objects can get such orbits, from which they can be moved inside the Solar…

Our planet is experiencing an accelerated process of change associated to a variety of anthropogenic phenomena. The future of this transformation is uncertain, but there is general agreement about its negative unfolding that might threaten…

This article investigates long-term orbits within the Earth's magnetosphere, specifically focusing on orbits where the argument of periapsis is synchronized with changes induced by lunar gravity assists and the Earth's argument of latitude…