Extra-planetary weather

Weather is not partial to just planetary bodies, however. A star's corona is constantly being lost to space, creating what is essentially a very thin atmosphere throughout the solar system, known as the solar wind.

Inconsistencies in this wind and larger events on the surface of the star, such as Coronal Mass Ejections, form a system that has features analogous to conventional weather systems i.e. pressure and wind, and though not true weather, is usually known as space weather. The activity of this system can affect planetary atmospheres and occasionally surfaces. The interface of the solar wind with the terrestrial atmosphere can produce spectacular aurorae, but can play havoc with electrically sensitive systems such as electricity grids and radio signals.

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Pitch

In music, pitch is the psychological associate of the fundamental frequency of a note. The note an above middle C played on any instrument is perceived to be of the same pitch as a pure tone of 440 Hz, but does not essentially contain a partial having that frequency. Furthermore, a slight change in frequency need not lead to a perceived change in pitch, but a change in pitch implies a change in frequency. In fact, the just perceptible difference is about five cents, but varies over the range of hearing and is more precise when the two pitches are played at the same time. Like other human stimuli, the perception of pitch also can be explained by the Weber-Fechner law.

Pitch also depends on the amplitude of the sound, especially at low frequencies. For instance, a low bass note will sound lower in pitch if it is louder. Like other senses, the comparative perception of pitch can be fooled, resulting in "audio illusions". There are several of these, such as the tritone paradox, but most especially the Shepard scale, where a continuous or discrete sequence of specially formed tones can be made to sound as if the sequence continues ascending or descending forever.

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Heat wave

A heat wave is a prolonged period of extremely hot weather, which may be accompanied by high humidity. There is no universal definition of a heat wave the term is relative to the usual weather in the area. Temperatures that people from a hotter climate believe normal can be termed a heat wave in a cooler area if they are outside the normal climate pattern for that area. The term is applied both to routine weather variation and to extraordinary spells of heat which may occur only once a century. Severe heat waves have caused catastrophic crop failures, thousands of deaths from hyperthermia, and widespread power outages due to increased use of air conditioning.

Heat waves often occur for the period of the Dog Days of summer; indeed the French term canicule, denoting the general phenomenon of a heat wave, derives from the Italian canicula applied to the star Sirius, also known as the "Dog Star."

Some regions of the globe are more susceptible to heat waves than others, such as Mediterranean-type climates with a summer dry spell which becomes much hotter than usual during certain years

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Solar System

The Solar System, is the stellar system comprising the Sun and the retinue of celestial objects gravitationally bound to it: the eight planets, their 162 known moons, three currently identified dwarf planets and their four known moons, and thousands of small bodies. This last category includes asteroids, meteoroids, comets, and interplanetary dust.

The principal component of the Solar System is the Sun ; a main sequence G2 star that contains 99.86% of the system's known mass and dominates it gravitationally. Because of its large mass, the Sun has an interior density high enough to sustain nuclear fusion, releasing enormous amounts of energy, most of which is radiated into space in the form of electromagnetic radiation, including visible light. The Sun's two largest orbiting bodies, Jupiter and Saturn, account for more than 90% of the system's remaining mass.

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