The R20 and R22 are ( parts of ) inner ringways around Brussels.

The names start with a R then a first digit indicating the ( old ) province, and sometimes a second digit to further differentiate in between different ringways.

There are also a number of orbital roads in Belgium around major cities.

* Ring I and Ring II, orbital roads around Helsinki, Finland.

Circumferential Highway may refer to one of the following beltways / orbital roads / ring roads:

Among the proposals was a series of orbital roads around the city with the outer ones built as American-style parkways-wide, landscaped roads with limited access and grade-separated junctions.

This category is for orbital roads, beltways, or ring roads.

Thus, the planetary model of the atom was discarded in favor of one that described atomic orbital zones around the nucleus where a given electron is most likely to be observed.

Spin is often depicted as a particle literally spinning around an axis, but this is a misleading and inaccurate picture: Spin is an intrinsic property of a particle, fundamentally different from orbital angular momentum.

Diamagnetism is believed to be due to quantum mechanics ( and is understood in terms of Landau levels ) and occurs because the external field alters the orbital velocity of electrons around their nuclei, thus changing the magnetic dipole moment.

The inner orbital route runs approximately around the heart of the Georgian city and the outer orbital route runs primarily along the natural circle formed by Dublin's two canals, the Grand Canal and the Royal Canal, as well as the North and South Circular Roads.

Upon orbital insertion around Jupiter, however, David Bowman is confronted with a huge, black featureless monolith with the exact proportions of 1 by 4 by 9 ( the squares of the first three positive integers ).

See of the University of Chicago and the United States Naval Observatory stated that the orbital anomalies proved the existence of a dark body in the 70 Ophiuchi system with a 36-year period around one of the stars.

Ephemeris time was defined in principle by the orbital motion of the Earth around the Sun, ( but its practical implementation was usually achieved in another way, see below ).

Although ephemeris time was defined in principle by the orbital motion of the Earth around the Sun, it was usually measured in practice by the orbital motion of the Moon around the Earth.

This corresponds to the fact that angular momentum is conserved in the orbital motion of the electron around the nucleus.

This effect is also explained by special relativity, and it leads to the so-called spin-orbit coupling, i. e., an interaction between the electron's orbital motion around the nucleus, and its spin.

The shaft turns three times for each rotation of the rotor around the lobe and once for each orbital revolution around the eccentric shaft.

A spacecraft traveling from Earth to Mars via this method will arrive near Mars orbit in approximately 8. 5 months, but because the orbital velocity is greater when closer to the center of mass ( i. e. the Sun ) and slower when farther from the center, the spacecraft will be traveling quite slowly and a small application of thrust is all that is needed to put it into a circular obit around Mars.

In astronomy, Kepler's laws of planetary motion are three scientific laws describing orbital motion, each giving a description of the motion of planets around the Sun.

Note that from the perspective of the smaller-mass object — from the moon, in the preceding example — a spacecraft might appear to orbit in an irregular path about the or point, but from the perspective above the orbital plane, it becomes clear that both the smaller mass and the spacecraft are orbiting the larger mass ( or more precisely, all of the objects are in orbit around the barycenter of the system ); they simply have overlapping orbital paths.

In magnetic materials, sources of magnetization are the electrons ' orbital angular motion around the nucleus, and the electrons ' intrinsic magnetic moment ( see electron magnetic dipole moment ).

Therefore magnetism is seen whenever electrically charged particles are in motion --- for example, from movement of electrons in an electric current, or in certain cases from the orbital motion of electrons around an atom's nucleus.

In the suborbital flight, the space craft went directly from launch to re-entry at the highest point ( point E on the picture ); in the orbital mission on the other hand, the craft went into an orbit around the Earth.

Because of the exponential nature of the rocket equation the orbital rocket needs to be considerably bigger.

All such cities are threatened with orbital bombardment unless they surrender.

In chemistry, Schrödinger, Pauling, Mulliken and others noted that the consequence of Heisenberg's relation was that the electron, as a wave packet, could not be considered to have an exact location in its orbital.

Metal complexes and electron deficient compounds ( e. g. diborane ) also appeared to be well described by molecular orbital theory, although valence bond descriptions have been made.

This explains also why the choice of z-axis for the directional quantization of the angular momentum vector is immaterial: an orbital of given ℓ and m ′ obtained for another preferred axis z ′ can always be represented as a suitable superposition of the various states of different m ( but same l ) that have been obtained for z.

Space elevators have also sometimes been referred to as " beanstalks ", " space bridges ", " space lifts ", " space ladders " or " orbital towers ".

In the case of two electrons occupying the same orbital, the Pauli principle demands that they have opposite spin.

If inversion through the center of symmetry in a molecule results in the same phases for the molecular orbital, then the MO is said to have gerade, g, symmetry.

If inversion through the center of symmetry in a molecule results in a phase change for the molecular orbital, then the MO is said to have ungerade, u, symmetry.

As for the spin function, which is responsible for the magnetism, we have the already mentioned Pauli's principle, namely that a symmetric orbital ( i. e. with the + sign as above ) must be multiplied with an antisymmetric spin function ( i. e. with a-sign ), and vice versa.

The physics principle behind orbital resonance is similar in concept to pushing a child on a swing, where the orbit and the swing both have a natural frequency, and the other body doing the " pushing " will act in periodic repetition to have a cumulative effect on the motion.

A mean motion orbital resonance occurs when two bodies have periods of revolution that are a simple integer ratio of each other.

For example, asteroids of the Alinda family are in or close to the 3: 1 resonance, with their orbital eccentricity steadily increased by interactions with Jupiter until they eventually have a close encounter with an inner planet that ejects them from the resonance.

A Laplace resonance occurs when three or more orbiting bodies have a simple integer ratio between their orbital periods.

A resonance between the precession of Saturn's rotational axis and that of Neptune's orbital axis ( both of which have periods of about 1. 87 million years ) has been identified as the likely source of Saturn's large axial tilt ( 26. 7 °).

Artificial satellites are too small to have an appreciable tidal effect on the planets they orbit, but several moons in the solar system are undergoing orbital decay by this mechanism.

While the majority of plutinos have low orbital inclinations, a substantial number of them follow orbits similar to that of Pluto, with inclinations in the 10 – 25 ° range and eccentricities around 0. 2 – 0. 25, resulting in perihelia inside ( or close to ) the orbit of Neptune and aphelia close to the main Kuiper belt's outer edge ( where objects have 1: 2 resonance with Neptune ).

Names will not be assigned to satellites until their orbital elements are reasonably well known or definite features have been identified on them.

Generally, a larger atom is more likely to absorb an X-ray photon, since larger atoms have greater energy differences between orbital electrons.

To change the preceding factors for orbital launch vehicles, proposed methods have included mass-producing simple rockets in large quantities or on large scale, or developing reusable rockets meant to fly very frequently to amortize their up-front expense over many payloads, or

Originally, Enterprise had been intended to be refitted for orbital flight, which would have made it the second space shuttle to fly after Columbia.

Most satellites have simple reliable chemical thrusters ( often monopropellant rockets ) or resistojet rockets for orbital station-keeping and some use momentum wheels for attitude control.