I am writing about a scientific book called 'The Guide To The Galaxy' by Nigel Henbest and Heather Couper

Critical Account of Scientific Reading I am writing about a scientific book called 'The Guide To The Galaxy' by Nigel Henbest and Heather Couper and published by the Press Syndicate of the University of Cambridge 1994. This book is about the galaxy in which our planet and our solar system lie. It contains information that goes beyond what most people or people with limited scientific knowledge know. The book talks about the efforts and the hard work by early scientists to discover more and more about our galaxy. It also talks about the most sophisticated techniques used nowadays to probe the galaxy. The first chapter investigates the discovery of our galaxy, illustrating the work by early thinkers and scientists. It starts with the origin of the name of our galaxy, Milky Way, which was named by the Romans. The chapter also talks about the conception of other civilisations about the 'Milky Way', such as the Greeks and their theory 'a stream of milk which gushed from the breast of the goddess Juno as she nursed the thirsty infant Hercules', while the North Americans thought of it as a route of ghosts on their way to the 'land of the hereafter'. The Eskimos saw it as a guide to travellers. The chapter then talks about some scientists like Galileo Galilei and his efforts in inventing the telescope, which took our knowledge of the galaxy into a whole new level. The

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  • Level: University Degree
  • Subject: Physical Sciences
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Exploring the Variable Luminosity of Star Systems.

Exploring the Variable Luminosity of a Star System "...variable stars have attracted the interest of amateur and professional astronomers alike for many decades." [1] When we look at the Universe we find that there are a seemingly innumerate number of stars, which vary in size, colour and luminosity. These variations are often due to the mass of the star, or what stage the star is in its lifetime. As a star ages its mass and luminosity will change, over periods of millions of years. However, when we look at stars in the night sky we find that a minority vary their luminosity over a period of days to a few weeks. These particular stars are catalogued as Variable Stars i.e. stars which vary in brightness. This can then be measured and be given a numerical value, in which we can compare the data, over a period of a few nights. If a variable star is close enough, then it is actually possible to visually see the difference. Variable stars are classified into two main categories: extrinsic and intrinsic. It is classified as extrinsic if the variability is caused by external factors; often binary stars or large planets, which eclipse the light in the star system. The intrinsic classification is given to stars that physically change or where a stellar event occurs, such as a stellar flare. [2]

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  • Level: University Degree
  • Subject: Physical Sciences
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Black Holes - Do they exist and if so what effect could they have on us?

Black Holes; Do They Exist And If So What Effect Could They Have On US? B lack Holes, a story for science fiction or is there truth behind their existence. These astrological anomalies are still a wonder to the greatest scientists in the world and not yet identified to truly exist. During this investigation I will be looking into the way in which ideas of Black Holes existence have developed over the years. Furthermore this investigation will also look into the ways in which a Black Hole can be identified and if so; what effects they would have on us. F irst, the question of "What is a Black Hole" needs to be answered. In simple terms a Black Hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull. Black Holes were once thought to be the monsters of the Universe, devouring everything around them in a frenzied cosmic feast. Black Holes are regions of space where gravity is so strong that not even light can escape, making them impossible to see. But we can see the debris that is being sucked in to these collapsed stars. Anything that approaches a Black Hole is first torn apart by it's immense gravitational force and then forms a flat rotating disc that spirals into the hole. The name "Black Hole" was not developed until 1967 but ideas around their existence have existed since the 18th

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  • Level: University Degree
  • Subject: Physical Sciences
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Alien Contact

Alien Contact Ever since primitive man first drew himself upright and stared up at the heavens, he has pondered the eternal question: Is there life out there? For thousands of years we have been enthralled by the awesome prospect of creatures, or beings existing out there in other galaxies, living in civilizations far more technologically advanced than our own. The monsters of science fiction may have been the product of writers imaginations, but to millions of readers such creatures are glimpses into the future. In our galaxy alone, there are more than a billion stars, and according to eminent astronomer Professor Archibald Roy, of Glasgow University, and also believes that at least one-fifth are stable and cool like our own Sun. About half of those billion stars, also have planets-the most important single requirement for developing life, Professor Archibald Roy thinks so. Astronomers hope that many of these planets will be surrounded be organic 'fog' containing DNA-like molecules which could be the key to life itself. In the late fifties, the Chinese-born astrophysicist Su-Shu Huang of Northwestern University, Illinois, described the types of conditions in which life could exist beyond our galaxy. It should be neither too hot, so that water would evaporate, nor too cold, sot that it would be permanently frozen. With a combination like this, there is no logical reason

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  • Level: University Degree
  • Subject: Physical Sciences
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Insolation refers to the deposition of radiant energy as heat into an absorbing body. Discuss

Insolation refers to the deposition of radiant energy as heat into an absorbing body. If the body is a planet, first obtain the declination of the Sun as seen from a pole of a planet, use equatorial coordinates. Let a planet have obliquity and the Sun have longitude and right ascension as viewed from the planet. From celestial to equatorial coordinate transformation, (1) where is the Sun 's declination. In general, the longitude of the sun will not be zero at the vernal equinox , but will be offset by an angle . perihelion for the earth, for example, occurs in January, while the vernal equinox is not until March. So it must be remembered that (2) We need to find the normal component of radiation at the north pole. But this flux will be simply (3) since the angular altitude of the Sun from the horizon is given by . Using (4) and plugging (4) into (1) and (4) gives (5) Now, we are interested in finding the average of this flux over a full orbit. If the orbit is eccentric, the time required to travel an orbital distance is not constant, but related to dt according to (6) (7) From (2), (8) which makes physical sense, since dt depends not on how the zero point for angular position is chosen, but on what the orbital distance is at the relevant position (the dependence). Equation (7) therefore becomes (9) To find the time-average flux, simply take (10)

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  • Level: University Degree
  • Subject: Physical Sciences
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Black Holes and the Origin of the Universe.

CTXT 1132/2126 BLACK HOLES AND THE ORIGIN OF THE UNIVERSE BLACK HOLES, WHITE HOLES AND PARALLEL UNIVERSES. A SHORT OVERVIEW. BY MICHAEL NAJDOVSKI. INTRODUCTION: Imagine a dark place, so dark not even light can escape; with forces so fierce they will tear apart any matter with the greatest of ease. Imagine a place in which all the laws of physics, that combine to make our universe the place that it is, vanish into inscrutable infinities, a place where space and time are so distorted you may travel to any one of an infinite number of parallel universes, each inhabited by a slight different parallel twin of yourself. This is the world of black holes, a phenomenon so bizarre even some of the worlds leading astrophysicists refuse to believe their existence. Yet there are those who believe, those who try to understand the concepts, but this is a subject were text book physics have no meaning and the very complex quantum mechanics and uncertainty play a large part. This short overview will skim through some of the basics behind this great mystery to try to give a simple explanation of the concepts behind black holes and some related topics. (NOTE: this is a very general overview and to try to explain the whole physics side of it will require some years of studying not to mention pages upon pages of information and formulas that would look like a bunch of meaningless,

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  • Level: University Degree
  • Subject: Physical Sciences
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Know caves in the United States.

In the United States, there are about 17,000 know caves. Rhode Island and Louisiana are the only states that do not have any caves. Only one hundred and twenty-five of these known caves have been opened to the public. Of the opened caves, fifteen are in national parks or monuments, thirty are in state parks, and the rest are privately owned and operated. Caves that have not been opened yet to the public should not be explored, except by experts. Neff Canyon in Utah is the deepest cave in the United States with a depth of 1,189 feet below the cave entrance. Carlsbad Caverns in New Mexico is the second deepest with a depth of 1,022 feet below the cave entrance. Carlsbad Caverns also has the largest cave room that has an area of fourteen acres. Carlsbad Caverns is now a dead cave, which means that it is no longer forming, there is not any running water, and the plants are not living. Even though it is a dead cave, it still has a lot of color inside the cave. In 1974, more than 670,000 people visited Carlsbad Caverns. Caves seem to be a natural wonder to many visitors. Caves have natural openings in the ground that lead deep into the body of the cave. These openings are called sinkholes, which are funnel-shaped structures that are the entrances to the caves. Caves remain at a constant temperature of 60 degrees all year round. Caves range in size from single small

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  • Subject: Physical Sciences
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Black holes

BLACK HOLES Black holes have many a mystery surrounding them. Lots of non-scientists do not even know what they are or what they do. Children believe (due to many science fiction stories) that Black Holes transport you to a different dimension. Hypothetically this idea could very well happen according to the strange nature of Einstein's equations but seems very unlikely. What is a Black Hole? Black holes were once thought to be the monsters of the Universe but are now thought to be fundamental to the creation of a galaxy. A black hole is a region of time in space from which nothing including light can escape making them impossible to see. However we know they are there because we can see the stuff near them getting sucked in because they are like a giant vacuum. Figure. 1 Figure. 1 shows the event horizon of a black hole. This is formed by rays of light that can't quite get away from the black hole but are always floating around the edge of them. At this part of a black hole the gravity is so intense that it tugs at time and space, causing space to slow down and stretch out. Here not even light can escape this intense gravity. Any body that comes near a black hole would firstly be ripped apart by the immense gravitational force and then upon reaching the event horizon the body would never be seen again and is thought to go irreversibly towards singularity, thus become

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  • Level: University Degree
  • Subject: Physical Sciences
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Life on Mars.

Mars Mars is the fourth planet from the Sun and the seventh largest in our solar system. It is situated, along with our planet, in the region of the solar system where liquid water can exist on the surface, and therefore there is a chance that life is (or once was) present on Mars. Mars or the Greek term Ares is named after the Roman god of War. The planet probably got this name due to its red color (from the abundant iron oxide in the soil) and is therefore sometimes referred to as the Red Planet. Its spinning period is almost identical to that of the Earth. Because its spinning axis is tilted with respect to the ecliptic plane by 24.5 degrees (similar to the tilt of Earth's axis) the surface of Mars experiences seasonal variations just like the Earth. Mars is also made up of a core, a mantle and a thin crust. The interior of mars has been determined from data collected at the surface. The data suggests that mars is made up of a dense core of approximately 700km radius, a molten rocky mantle denser than earths and has a thin crust. Data from Mars Global Surveyor indicates Mars' crust is about 80km thick in the Southern Hemisphere but it is only 35km thick in the Northern Hemisphere. Mars' low density suggests that te core is made up of large amounts of sulphur and iron. Is Water needed for life to exist? We have always been fascinated with the Red Planet, and we've

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  • Level: University Degree
  • Subject: Physical Sciences
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The Big Bang Theory

The Big Bang Theory God created the world in seven days was the concept everyone had acknowledged, until a man named Edwin Hubble, began his research. Hubble was the man who was responsible for obtaining evidence for The Big Bang Theory. His theory caused a lot of upsets in the community at the time, but in today's world, people believe that the Big Bang theory was correct while others are still against it. Before the Big Bang, all of the matter and radiation of our present universe were packed together in the primeval fireball (an extremely hot dense state). The theory stated that the entire universe began from a colossal explosion of this fireball, which took place according to astronomers approximately fifteen billion years ago. The exact nature of this big bang explosion may never be known. However there have been some theoretical breakthroughs, based on the principles of the "Quantum theory". It is believed that before the universe began it was full of random actions creating a chaos, which is referred too as "Quantum weirdness", it is believed that at some point in the randomness a small bubble was formed with an temperature in excess of 10 to the power of 34 degrees. Due to the immense temperature the bubble inevitably expanded. For an extremely short period of time (billionths of billionths of a second) the bubble inflated, at the end of the inflation the universe

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  • Level: University Degree
  • Subject: Physical Sciences
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