Most of the craters on the surface of the Moon were created by the collision of minor bodies of the Solar System, in particular asteroids coming from the Main Belt as a consequence of different types of resonance. Our aim is to investigate the dynamics of such asteroids, paying special attention on the hyperbolic invariant manifolds associated with the equilibrium point L2 of the Earth – Moon s...

The present research studies the motion of a particle or a spacecraft that comes from an orbit around the Sun, which can be elliptic or hyperbolic, and that makes a passage close enough to the Earth such that it crosses its atmosphere. The idea is to measure the Sun-particle two-body energy before and after this passage in order to verify its variation as a function of the periapsis distance, a...

Coronal mass ejections (CMEs) are the most dynamic phenomena in our solar system. They abruptly disrupt the continuous outflow of solar wind by expelling huge clouds of magnetized plasma into interplanetary space with velocities enabling to cross the Sun-Earth distance within a few days. Earth-directed CMEs may cause severe geomagnetic storms when their embedded magnetic fields and the shocks a...

The recent discovery that the Earth is retarding each year by a fraction of a second its revolution around the Sun led to investigations and speculations about the cause of such a defect in what was thought to be a perfect clock. The emission of thermal radiation by the Sun cannot justify this discrepancy even if a fraction of unknown dark matter is added to increase the Sun mass loss. The incr...

In these lectures we will develop a quantitative model to describe the structure of the observable Universe as a whole. To begin, let us review the relevant physical scales. An Earth mass is 6× 1027 g ≃ 3 × 1051 GeV/c2 ≃ 3× 10−6 M⊙. Its radius is 6.4 × 10 8 cm. It spins around the Sun, which has a mass M⊙ = 2 × 10 33 g ≃ 1057 GeV/c2 and radius R⊙ ≃ 7 × 10 10 cm. The Earth-Sun distance is 1AU = ...

Recently, Jenkins, Fischbach and collaborators have claimed evidence that radionuclide half-lives vary systematically over a ±0.1% range as a function of the oscillating distance between the Earth and the Sun, based on multi-year activity measurements. We have avoided the time-dependent instabilities to which such measurements are susceptible by directly measuring the half-life of (198)Au (t(1/...