CHAPTER 1
INTRODUCTION
The upper part of atmosphere above 50 km is of importance to mankind. It acts as a shield to extreme ultraviolet and x-radiations harmful to human life. It also plays an important role in communication and navigation. The regions of atmosphere are defined in terms of ionization, temperature and composition. In terms of ionization, the region extending from 50 to 1000 km above the earth surface is called ionosphere. It consists of weakly ionized gas containing a large number of neutral molecules and relatively smaller number of electrons and ions. The main source of ionization are rays emitted from the sun, which results in formation of overlapping layers namely D, E, F1 and F2. In each layer, the ionization density peaks at a certain altitude and decreases above and below it. The D region has lowest ionization density and is available only during daytime. The ionization density has a peak value around 90 km. It is an absorbing region for radiowaves. The E region is known as the current bearing region. It lies in the range of around 90-125 km. The peak density in this layer is at about 120 km. It contains both the normal E and sporadic E layer. The electron density in E region starts decreasing with sunset and achieves an equilibrium value at night. The F region lies in the range of 125-600 km. It is divided into two layers, namely, F1 and F2 during daytime which merges to form a single layer during night. The F1 region has a peak density at around 200 km. It disappears after sunset. The F2 region has a peak density at about 300 km in day and the region extends to higher altitudes at night. After sunset, the electron density increases near the peak of the F-layer. The density attains an equilibrium value dur...
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...ns in phase but also in amplitude.
In order to develop the basic equations of scintillation theory, the following assumptions were taken by Tatarskii [1971] (1) The temporal variations of the irregularities is much slower compared to the wave period and the time taken by the signal to traverse through the irregularity layer is negligible compared to the time scale of temporal variation and (2) the operating wavelength is much smaller than the characteristic size of the irregularities.
If a radiowave of constant amplitude is incident on the irregularity slab of thickness L (Fig 2.2) where the layer is assumed to be a phase changing screen, the wave changes its phase when propagates through it. The emergent wave is represented as,
U0(ρ) = A0 exp [ -j φ(ρ)]
"Radar during World War II." - GHN: IEEE Global History Network. N.p., n.d. Web. 16 Feb. 2014. .
Glickman, Todd S. (ed.) (2000). Glossary of Meteorology (2nd ed.). American Meteorological Society. ISBN 978-1-878220-34-9.
All instruments aboard the SOHO spacecraft fall under one of the following headings based on what area of the Sun it is suppose to observe and measure: the solar interior, the solar atmosphere, or the solar wind. The solar interior instruments such as GOLF (Global Oscillations at Low Frequencies) and VIRGO (Variability of Solar Irradiance and Gravity Oscillations) both perform oscillation measurements of the full solar disk which obtains information concerning the solar nucleus. In addition, the instruments that measure the solar atmosphere such as the CDS (Coronal Diagnostics Spectrometer) and UVCS (Ultraviolet Coronograph Spectrometer) observe both the inner and outer corona. They obtain measurements of temperature, density, composition, and velocity in the corona with high resolution. Finally, the instruments that analyze and measure the solar wind include ERNE (Energetic and Relativistic Nuclei and Electron experiment) and CELIAS (Charge, Element, and Isotope Analysis System) which measure the charge state and isotopic composition of ions in the solar wind. These two instruments also determine the charge and isotopic composition of energetic particles generated by the Sun.
Within our Solar System lies an abundance of planets, each with their own unique characteristics, including the Terrestrial planets of Venus, Earth, and Mars who vary in many aspects but, most importantly, their atmosphere.
Radiation has always been in everyday life even before Roentgen discovered x-ray. The mountains give off natural radiation, other forms of radiation are coal burning power plants, x-rays from a TV, and an airplane ride. The average dose from background radiation is about 360 mrem every year. There are two types of radiation, nonionizing and ionizing radiation. Examples of nonionizing radiation are microwaves and radio waves broadcasting. Ionizing radiation refers to gamma and x-rays. Ionizing radiation means that the rays are able to remove an electron from the atom then ions can be formed. The ions can cause damage when reacting with other atoms. Cells are able to be repaired if low dose are received. However, if cells get a high dose, the cells will be damaged or possibly die. If the cell is damaged permanently then it is referred to as a mutated cell.
Solar wind is an example of space weather. Solar wind is when the a star ejects particles from its corona. These particles are usually electron and protons and the rate of ejection depends solely on the stars activity at the time. Space weather are the conditions in the space environment that humans are interested in because they have impacts on the health and safety of equipment and humans in space and on the ground. Examples of space weather are the particle density, IMF-interplanetary magnetic field-, strength and orientation, and the number of protons and electrons. Space weather can be both celestial and deadly; the most mystical things can be a result of space weather but deadly consequences too. Space weather depends mainly on the star, for example: the stars activity, the intensity of the stars flares,...
The biological effects of radiation play a key role in today’s society and it is something that all species have to deal with on a day-to-day basis. Throughout time, this field of study has grown and has become one of the most prominent fields of science. Radiation is something that we as a human race will never be able to escape. It is naturally present and has been since planet Earth was formed. In the mid 19th Century, there were two famous scientists that are known for their exquisite contributions to the study of radioactivity. Pierre and Marie Curie were a husband-wife duo that both studied at the Sorbonne. While at Sorbonne, they studied the properties of thorium and uranium and soon stumbled upon and discovered the element polonium. Pierre then decided to study magnetism at high temperatures. Marie proceeded to study in both chemistry and physics and received Nobel Awards in both fields. She is the only person in history to do this. The “curie” is a unit of measure that scientists use to this day in radiation studies. These two were not...
Type of gaseous particles (atoms of oxygen and nitrogen) and the altitude of the colliding are making many different colors of auroras at altitudes from 20 to 200 miles above the earth 's surface. The common colors and the brightest are glittering green-yellow which produced by oxygen atoms located 60 miles (100 kilometers) above the earth. Conversely, all-red auroras are rare to see and produced by high-altitude oxygen atoms at 200 miles (320 kilometers) above the earth by extremely energetic solar particles. Ionized nitrogen molecules produced blue or purple
...e amid these interfaces. The contraption will understand these waves as parallel lines alongside equal distances amid them, and cut density for the deeper lines, because the imitated waves come to be softly lesser in number. This aftermath in a stripped outline possessing alternating dark and clear lines at usual intervals [Figure 5].[6]
A solar storm refers to space weather involving solar activities like solar flares and coronal mass ejection. Although most solar storms may only have minor effect on the Earth, a particularly strong one like the 1859 Carrington Event is likely to cause damage of spacecraft and satellites, as well as radio and electricity blackout of large regions on the Earth. In the age that people’s lives are greatly dependent on electronic and telecommunication technologies, our modern civilization is under a constant threat posed by a hazardous solar storm. This paper will examine a few past solar storm observations and attempt to analyze the effects of the major components of solar storms on human technologies and people’s lives.
Radiation is a frightening concept. It has lead to many an untimely death in the past 70 years, ranging from victims of atomic bombs in Japan to physiologists experimenting without taking proper safety precautions. The most dangerous form of radiation can be devastating to the body, weakening or eliminating the immune system and tearing the very DNA in one’s cells apart. This form is referred to as ionizing radiation, and even the least harmful potencies - such as x-rays and UV light - can increase the risk of cancer and other health problems. It has enough energy to knock electrons out of atoms in a process called ionization.
The strength of scintillation can be measured in terms of the variance of the beam amplitude
There are eight planets in our solar system. The first planet closest to the sun is Mercury. Therefore, Mercury is the hottest planet. Mercury’s surface is cold. However, in the daytime Mercury can get as hot as 840 degrees fahrenheit, which is 450 degrees celsius. During night time the temperature can decrease to 275 degrees fahrenheit, or -170 degrees celsius. Mercury is the smallest planet. Mercury is the quickest planet to move around the sun. Its speed is approximately 112,000 mph along its elliptical orbit. Mercury can move around the sun in 88 days. There are craters in mercury, and scientist believe ice is in the craters.
Earth system refers to the earths interacting physical, biological, and chemical processes. The system consists of land, oceans, atmosphere and poles. The earth system has four spheres, including the geosphere, the hydrosphere, the atmosphere, and the biosphere. The geosphere refers to the solid parts of the earth system, including earth’s rocky crust, mantle, and the metallic core. Within the geosphere is the lithosphere, which only refers to the uppermost layers of solid earth. The uppermost layers of solid earth are the oceanic and continental crust rocks. Just below the crust is the mantle, which is composed mostly of magnesium and iron silicate minerals. The mantle accounts for about 2/3 of the