Neutrons are found at the center or nucleus of an atom. They are electrically neutral, which means they don’t have either a positive or a negative charge. It is believed that if a proton (which is positively charged) and an electron (which is negatively charged) are smashed together, the result would be a charge-less particle that is a neutron. Apart from smashing these particles, neutrons are hard to observe. Because they have no charge means that they do not react to electromagnetic forces, unlike protons and electrons. They therefore cannot be observed using electromagnetic manipulation.

Experiments on sub-atomic particles in a laboratory, like smashing them up, can be really costly and complicated. A cheaper but effective alternative that allows scientists to study neutrons is to look at the stars and examine their behavior. It has been found that a specific celestial body called a neutron star consists mostly of neutrons. A neutron star is produced from an explosion of a supernova, where protons and electrons are smashed together and combined to become neutrons. Neutron stars are incredibly dense because their whole mass is packed within a very little space. They are believed to be at the end stage of a star’s life cycle.

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To understand it better, a comparison with a similar phenomenon in sound waves called Doppler Effect is used. Imagine that you are riding in the car moving towards the north when suddenly an ambulance passes by going in the opposite direction. You will notice that as you and the ambulance move closer to each other you will hear a higher frequency of the siren while as you move farther away from each other, you will hear a lower frequency of sound. Light behaves in a similar way because it has wave-like properties.

With regards to astronomy, the universe has been known to be continuously expanding and along with it galaxies tend to move away from us. Accordingly, the light emanating from these galaxies is redshifted or change into longer wavelengths. This shift isn’t observed by the naked eye and is usually measured by comparing the spectrum produced by this light to that of a reference laboratory spectrum. By comparing the spectrum to known wavelengths, astronomers are able to determine the redshift occurring from these distant sources.

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But what is relativity all about and how was it able to answer these questions? We can begin with what Einstein came up with, the idea that if we are to believe that the natural laws of the universe are absolute and true then they must be true under all circumstances and at all times. According to him, this is only made possible when elements such as space, time, matter, and energy are altered or are changed constantly in order to present us with the same circumstance every time. Applying that to observations of the universe, he supposes that even empty space can contract or expand depending on the position of the person observing it.

In astronomy, relativity has found its place especially when observing or studying objects that move in a strong gravitational field as well as those that are moving near the speed of light.

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A radio wave actually pertains to a type of electromagnetic radiation. Like other types of waves in the electromagnetic spectrum, a radio wave is produced by acceleration of an electric charge and has both electric as well as magnetic components.

Waves of the electromagnetic spectrum are arranged either according to frequency or wavelength. The higher the frequency of the wave, the shorter is the wavelength and vice versa. In the waves of the electromagnetic spectrum ordered based on decreasing frequency, gamma rays come first, followed by x-rays, ultraviolet radiation, then visible light, infrared, and finally microwave and radio wave. This means that radio waves have the lowest frequency but the longest wavelength.

The existence of radio wave was discovered through the mathematical work of James Clerk Maxwell and demonstrated by Heinrich Hertz. What makes radio waves and other waves of the electromagnetic spectrum interesting is that they are able to travel even without the existence of a medium for transmission. They are, thus, able to travel from interplanetary or interstellar space toward the Earth.

The discovery of radio wave has brought about the existence of useful applications for man including in the fields of communication and medicine. For instance, radio frequency energy has long been used in less invasive medical procedures.

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A shock wave is characterized by the sudden and nearly discontinuous change within different mediums.

It is caused by the tremendous rapid rise in temperature, pressure, or even with the density of the flow in the atmosphere. In a conventional supersonic flow, the expansion is attained through expansion fans.

Shockwaves always travel at much higher speeds when compared to the usual, ordinary wave. Unlike other kinds of non-linear waves, the shock wave’s energy disperses quickly as it travels. However, the approach of the accompanying expansion wave partially cancels out the energy as it merges with the shock wave. This is what causes the sonic boom which comes with the passage of any supersonic aircraft through the sound wave that results in a expansion wave merger.

Physically, shockwaves in the air are typically heard of as that loud snap or cracking noise. And over long distances, shockwaves can naturally change from non-linear waves into linear waves. This then degenerates into a sound wave conventionally as it reacts to its surroundings, heating the surrounding air thereby losing the energy. This sound wave is the normal thump or thud of the sonic boom that is commonly created in flight of a supersonic aircraft.

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Precession has types. In Physics, these are none other than the Torque-Induced and Torque-Free classes. In the Torque free type, it refers to the occasions when a certain body’s rotational axis goes off slightly from the position that the object can rotate in a balanced and free motion. It usually involves a maximum or minimum principal axis, most commonly known as the rotational inertia. Torque Induced or gyroscopic precession on the hand, is the phenomenon when a certain rotating object suddenly wobbles when torque or force is applied. To put it simply, when an outside force acts on a rotating object like a spinning top hitting a hump on the surface it was used, the top wobbles and goes off-balance.

In astronomy, these types of precession apply, but only as an application or theory. The types of astronomical precession are namely: Axial, Ecliptic and Perihelion Precession. Axial Precession is the movement of a celestial body’s rotational axis, in the manner that as if it was making a cone shape. Ecliptic alternatively, refers to the planet’s orbital inclination drifts up or down. And Perihelion is the type of precession that combines both the axial and ecliptic types. The only difference is that it refers to the direction of orbit around the sun.

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Depending on the application, the exact angles between each surface differs. Traditionally, a prism is that of a triangular prism, with a triangle shaped base and rectangular sides. Most prisms are made of glass, though it can also be made of other transparent material, equal to the wavelength to which they are meant to be used.

It can be used to break up light to its equivalent spectral colors, which include the colors red, orange, yellow, green, blue, indigo and violet. It can also reflect light or even split light into various wavelength.

Prisms work in dependence to light. As the speed light changes from one medium to another (e.g. light from air and into the section of the prism), it then causes light to be refracted and then enter the new medium, this time at a different angle or view. This is the basic principle of using a prism. Aside from this, the angle or the bending level of the light is hugely dependent on the angle where the light hit the object, and also varies in terms of wavelength due to the refractive ratio of the two light gathering objects.

There are also other types of prism: namely, the dispersing, grating, reflecting and polarizing types. The dispersing prism is the common type, where it breaks light into spectral colors. Grating prisms are used for light diffraction or splitting. Reflecting prisms are used in binoculars to reflect light. And polarizing on the other hand is used for splitting light into different spectrums.

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The planck scale is the smallest unit of measurement recognized by physical theory. Physicists use this scale to measure the smallest sizes or the shortest lengths of time that can exist. Named after Max Planck, who is the founder of quantum theory, this scale has given many physicists a way to envision space and time in smaller proportions—or, more specifically, in grainy proportions. This idea is the complete opposite of the relativity theory which believes space to be a continuous stretch of un-grainy matter.

Physicists currently cannot prove what really happens at the planck scale. And this is because in psychics, the smaller something is, the bigger the amount of energy is required to study it. This is because as the energy of a photon (quantum of electromagnetic energy) increases, so does its size measured in wavelengths decreases. This means, the smaller the granule, the hotter is its energy.

The energy required to study space granularity is known as the planck energy, which is believed to be about a quintillion (1 followed by 30 zeros) times larger than the energies currently conceivable by any particle accelerators in the world. Although experimental evidence to back-up the planck scale dynamics is hard to come by, measuring instruments like the WMAP probe has led physicists to believe that there could actually be a time when our universe achieved planck scale energies.

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Photovoltaic (PV) utilizes solar cells, which are often embedded in the solar panels to capture the energy coming from the Sun. Energy is created when these solar cells are continuously exposed to light, specifically to sunlight, exhibiting the photovoltaic effect. When this is in progress, the photons are excited or pushed into a higher energy state to produce electricity. Photodiodes are responsible for the unbiased operation in photovoltaic devices where power is produced entirely by the transduced light energy. The growing demand for renewable energy resources have resulted to the drastic developments and innovations in photovoltaic reserach (PV), resulting in more sophisticated and high quality solar panels.

These solar panels must be resilient to the wear and tear caused by the changing environmental conditions. Most solar panels today are protected by glass sheets to ensure the efficiency of the solar cells and the optimum photovoltaic (PV). With the Sun’s significant role on Earth, the light it emits has limitless possibilities for practical day-to-day usage.

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Parallax provides astronomers with a simple method of calculating the distance of many celestial objects. As the Earth revolves around the Sun, celestial objects seem to be located at different positions when observed month after month. When a star is observed during June and December, observers can make use of two different viewpoints or lines of sight to the star to measure the distance. These two lines of sight intersect at the star being observed, forming an angle and half of this angle is the parallax. Typically, the distance is measured in parsecs by getting the inverse of the observed parallax measured in arc seconds.

There are different kinds of parallax, namely, stellar, solar, lunar, diurnal, and dynamic or moving cluster. It is important to keep in mind that parallax decreases with distance and can only be used to measure celestial objects at a maximum distance of 100 parsecs. The use of this concept in astronomy is extended with much precision through the use of the Hipparcos satellite.

Geometric Technique – Parallax

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