Wyatt and Whipple, 1950 ), which is a retardation of the orbital motion of particles by the relativistic aberration of the repulsive force of the impinging solar radiation, causes the dust to spiral into the sun in times much shorter than the age of the Earth.

* A solar calendar is based on perceived seasonal changes synchronized to the apparent motion of the Sun ; an example is the Persian calendar.

The declinations of solar system objects change very rapidly compared to those of stars, due to orbital motion and close proximity.

From the comparison of formulae ( 2 ) and ( 3 ), both of which express the same real solar motion in the same real time but on different time scales, Clemence arrived at an explicit expression, estimating the difference in seconds of time between ephemeris time and mean solar time, in the sense ( ET-UT ):

These measurements can be considered as secondary realizations ( in a metrological sense ) of the primary definition of ET in terms of the solar motion, after a calibration of the mean motion of the Moon with respect to the mean motion of the Sun.

Hipparchus ( 190 – 120 BC ), focusing on astronomy and mathematics, used sophisticated geometrical techniques to map the motion of the stars and planets, even predicting the times that solar eclipses would happen.

Kepler was able to summarize the carefully collected data of his mentor-Tycho Brahe-with three statements that described the motion of planets in a sun-centered solar system.

Some eight decades later, Isaac Newton proved that relationships like Kepler's would apply exactly under certain ideal conditions that are to a good approximation fulfilled in the solar system, as consequences of Newton's own laws of motion and law of universal gravitation.

Waves ( ripples and flapping motion ) along the magnetopause move in the direction of the solar wind flow in response to small scale variations in the solar wind pressure and to Kelvin-Helmholtz instability.

The soot would absorb enough solar radiation to heat surrounding gases, setting in motion a series of chemical reactions that would break down the stratospheric ozone layer protecting Earth from harmful ultraviolet radiation.

In the geocentric model of the solar system, the celestial spheres model was originally used to explain the apparent motion of the planets in the sky in terms of perfect spheres or rings, but after the planets ' motions were more accurately measured, theoretical mechanisms such as deferent and epicycles were added.

As a consequence, an accurate measurement of the earth ’ s axial reorientation relative to objects outside the frame of the moving galaxy ( such as distant quasars commonly used as precession measurement reference points ) must account for a minor amount of non-local torque-free precession, due to the solar system ’ s motion.

19th-and 20th-century astronomical observations revealed that the mean solar day is slowly but measurably lengthening and the length of a tropical year is not entirely predictable either ; thus the sun – earth motion is no longer considered a suitable basis for definition.

Together with his other laws of planetary motion, this allowed him to create a model of the solar system that was an improvement over Copernicus ' original system.

Secondly there is an apparent increase in the Moon's angular rate of orbital motion ( when measured in terms of mean solar time ).

A combination of lunar gravity, solar gravity, and the flattening of the Earth at its poles causes a precession motion of the orbital plane of any geostationary object, with a period of about 53 years and an initial inclination gradient of about 0. 85 degrees per year, achieving a maximum inclination of 15 degrees after 26. 5 years.

For accurate astronomical work on land, it was usual to observe sidereal time rather than solar time to measure mean solar time, because the observations of ' fixed ' stars could be measured and reduced more accurately than observations of the Sun ( in spite of the need to make various small compensations, for refraction, aberration, precession, nutation and proper motion ).

Next, the time scales based on Earth's rotation are not uniform and therefore are not suitable for predicting the motion of bodies in our solar system.

The other is magnetic heating, in which magnetic energy is continuously built up by photospheric motion and released through magnetic reconnection in the form of large solar flares and myriad similar but smaller events — nanoflares.

The musician employing the serial technique of composition establishes a mathematical system of rotations that, once set in motion, determines the sequence of pitches and even of rhythms and intensities.

There is a sophisticated security system with highly sensitive motion detectors, remote cameras, and the latest in card readers and key pad security locks bind the campus.

* A cooling system to reduce atomic motion, such as a helium refrigeration circuit.

Despite their embrace of the principle of rectilinear inertia and the recognition of the kinematical relativity of apparent motion ( which underlies whether the Ptolemaic or the Copernican system is correct ), natural philosophers of the seventeenth century continued to consider true motion and rest as physically separate descriptors of an individual body.

In the visual system, for example, sensory signals from the eyes are transmitted to the thalamus and then to the primary visual cortex ; inside the cerebral cortex they are sent to areas that extract features such as three-dimensional structure, shape, color, and motion.

In March 2007 it organised a rally in Parliament Square to coincide with the Commons motion to renew the weapons system.

For trajectories other than circular motion, for example, the more general trajectory envisioned in the image above, the instantaneous center of rotation and radius of curvature of the trajectory are related only indirectly to the coordinate system defined by u < sub > ρ </ sub > and u < sub > θ </ sub > and to the length | r ( t )|

Local coordinate system for planar motion on a curve.

In this local coordinate system the acceleration resembles the expression for nonuniform circular motion with the local radius ρ ( s ), and the centripetal acceleration is identified as the second term.

Conservation of angular momentum in the Earth-Moon system requires that the angular momentum lost by the Earth due to tidal friction be transferred to the Moon, increasing its angular momentum, which means that its moment arm ( its distance from the Earth ) is increased ( for the time being about + 3. 8 cm / year ), which via Kepler's laws of planetary motion causes the Moon to revolve around the Earth at a slower rate.

Digital Cinema Initiatives ( DCI ) was formed in March 2002 as a joint project of many motion picture studios ( Disney, Fox, MGM, Paramount, Sony Pictures Entertainment, Universal, and Warner Bros. Studios ) to develop a system specification for digital cinema.

When matter ( ordinary material particles ) is changed into energy ( such as energy of motion, or into radiation ), the mass of the system does not change through the transformation process.

Similarly, a system may transfer energy to another by physically impacting it, but in that case the energy of motion in an object, called kinetic energy, results in forces acting over distances ( new energy ) to appear in another object that is struck.

As a result, there is no possibility of a perpetual motion system.

Alternatively entropy can be defined from a classical thermodynamics viewpoint, in which the molecular interactions are not considered and instead the system is viewed from perspective of the gross motion of very large masses of molecules and the behavior of individual molecules is averaged and obscured.

In 1921, his third year at the university, he published his first scientific works in the Italian journal Nuovo Cimento: the first was titled: On the dynamics of a rigid system of electrical charges in translational motion ; the second: On the electrostatics of a uniform gravitational field of electromagnetic charges and on the weight of electromagnetic charges.

On 18 March, Friese-Greene sent a clipping of the story to Thomas Edison, whose laboratory had been developing a motion picture system known as the Kinetoscope.

For a single degree of freedom oscillator, a system in which the motion can be described by a single coordinate, the natural frequency depends on two system properties: mass and stiffness ; ( providing the system is undamped ).

Three years later came the paper that would make his name famous, Sur les équations du mouvement relatif des systèmes de corps ( On the equations of relative motion of a system of bodies ).

If F is the only force acting on the system, the system is called a simple harmonic oscillator, and it undergoes simple harmonic motion: sinusoidal oscillations about the equilibrium point, with a constant amplitude and a constant frequency ( which does not depend on the amplitude ).

It is alphabetic, with a letter or diacritic for every phonemic ( distinctive ) hand shape, orientation, motion, and position, though it lacks any representation of facial expression, and is better suited for individual words than for extended passages of text.

Grip and throw as in the sidearm but performed with an overhead motion: disc orientation nearly perpendicular to the ground over much of the flight.

Since external torque is minimized by mounting the device in gimbals, its orientation remains nearly fixed, regardless of any motion of the platform on which it is mounted.

Like many other sign languages, BSL phonology is defined by elements such as hand shape, orientation, location, and motion.

A frame of reference in physics, may refer to a coordinate system or set of axes within which to measure the position, orientation, and other properties of objects in it, or it may refer to an observational reference frame tied to the state of motion of an observer.

We can imagine the curve as the path of motion of some object, with the orientation indicating the direction in which the object moves.

While this orientation is rather conducive to the double pump motion, Spud Webb was known to perform the dunk while facing the basket.

For more sophisticated applications, such as welding and finishing ( spray painting ), motion must be continuously controlled to follow a path in space, with controlled orientation and velocity.

The report goes on to say, " The relatively steep flight path angle and the attitude ( the orientation of the aircraft relative to the horizon, direction of motion etc.

When the magnetic field is subsequently switched off, the heat capacity of the refrigerant rises again because the degrees of freedom associated with orientation of the dipoles are once again liberated, pulling their share of equipartitioned energy from the motion of the molecules, thereby lowering the overall temperature of a system with decreased energy.

As the differential carrier rotates, the changing axis orientation of the planet gears imparts the motion of the ring gear to the motion of the sun gears by pushing on them rather than turning against them ( that is, the same teeth stay in the same mesh or contact position ), but because the planet gears are not restricted from turning against each other, within that motion, the sun gears can counter-rotate relative to the ring gear and to each other under the same force ( in which case the same teeth do not stay in contact ).

Like all cephalopods, giant squid have organs called statocysts to sense their orientation and motion in water.

Stability deals with small perturbations in angular displacements about the orientation at the start of the motion.

A non-rotating hubcap retains the same orientation even when a vehicle is in motion.

An Inertial Navigation System ( INS ) is a navigation aid that uses a computer and motion sensors ( accelerometers ) to continuously calculate via dead reckoning the position, orientation, and velocity ( direction and speed of movement ) of a moving object without the need for external references.

Rolling motion changes the orientation of the aircraft's wings with respect to the downward force of gravity.

Its normal mode of operation maintains its orientation so that the instruments will look away from the earth, with a “ rocking ” motion to equalize the coverage of the sky.

All these methods actually define the orientation of a basis set ( or coordinate system ) which has a fixed orientation relative to the body ( i. e. rotates together with the body ), relative to another basis set ( or coordinate system ), from which the motion of the rigid body is observed.

These use small stones and a viscous fluid to stimulate hair cells to detect motion and orientation.

Space motion sickness is caused by changes in g-forces, which affect spatial orientation in humans.

ATP binding and hydrolysis as well as ADP release change the conformation of the microtubule-binding domains and the orientation of the neck linker with respect to the head ; this results in the motion of the kinesin.