GABRIEL THIEL
UNIVERSE AND OTHER WONDERS In what world do we live? SCIENCE
2013
COLEGIO AMANECER ZONA 12
INDEX 3
UNIVERSE
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GENERAL DEFINITION
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ORIGIN
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ORIGIN OF STARS
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SPIRAL GALAXY
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ELLYPTICAL GALAXY
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IRREGULAR GALAXY
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OUR OWN GALAXY
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ORIGIN OF PLANETS
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OUR SOLAR SYSTEM
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HOW WE STUDY OUR UNIVERSE
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NAKED-EYE OBSERVATION
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OPTICAL TELESCOPES
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STATE-OF-THE-ART IN OPTICAL TELESCOPES
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NON-VISIBLE LIGHT TELESCOPES
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CLASSIFICATION BY LOCATION
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TELESCOPIC IMAGES OF DIFFERENT TELESCOPE TYPES
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OTHER WAYS OF STUDYING THE UNIVERSE
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MANNED FLIGHTS
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UNMANNED SPACE EXPLORATION
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IMPORTANCE OF ASTRONOMICAL STUDIES
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Universe GENERAL DEFINITION From the point of view of astronomy, the universe is all existing matter, energy and space considered as a whole. ORIGIN The most accepted theory about the origin of the universe is the “Big Bang”. It says that all existing matter was concentrated in a point of infinite density, and received an external injection of enormous energy (I personally believe that it was injected by God, as the Catholic Creed affirms when saying “I believe in God, the Father Almighty, Creator of heaven and earth”). This energy impulsed all matter in all directions, and even now, the universe is growing in size because of this. It may have looked like this:
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ORIGIN OF STARS Not all matter traveled at the same speed after the “big bang�, so in some places, it formed bodies of high density of helium and hydrogen that had more and more temperature, as the pressure increased, until the atomic nuclei began to fuse, relasing enormous amounts of energy, perceived as heat and light. The oldest stars began this process from 10 to 14 billion years ago. The age of our own star, the sun, is of about 5 billion years. They group in galaxies (groups of stars) with different shapes:
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SPIRAL GALAXY:
ELLYPTICAL GALAXY
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IRREGULAR GALAXY
OUR OWN GALAXY In the following image, we see the Milky Way, the name given to the galaxy where we live. It was given this name because it looks as if someone has spilled milk in the sky. The text on the image speaks about “LIGTH YEARS� and it is a very useful measuring unit when speaking about the universe, because distances are so big, that expressing them in normal units would present us with enormous numbers. Therefore, we use Light Year which is the distance traveled by light in one year. Remember that in just one second, light travels almost 300,000 kilometers (299,792.458 if you need the exact number).
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ORIGIN OF PLANETS We already spoke about matter condensing into stars. During this process, the matter is spinning like water going down a drain, sending some matter away. The matter that is sent away start to condense into solid objects, and once their gravity is strong enough, they grow into large bodies. Some of them become planets, the less massive ones become satellites and the other ones become asteroids, meteroids and comets. The planets remain spinning around the star that was being formed with them, in elliptic orbits, forming what is
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known as SOLAR SYSTEMS. We already saw the position of our solar system on the Milky Way. Following, you will see a representation of our solar system, which is formed by 8 planets and includes also 4 exoplanets. One of them is nearer to the sun than Jupiter and the other 3 are Pluto and two other farther ones. The formal definition of an exoplanet is: a big rock that does not have the ideal size to be classified as a planet (more on this after the image) and its surface is generally a mix of frozen gasses.
Our Solar System
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In August, 2006 the International Astronomical Union (IAU) defined 3 conditions to declare a heavenly body a planet: It has to orbit a sun It has to be a circular objet and keep that shape His gravity has to attract almost every thing that passes near it The names of the planets than orbit around the sun are, from nearer to farthest from the sun: -
Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune
The exoplanets are: - Pluto - Eris - Ceres
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HOW WE STUDY THE UNIVERSE NAKED-EYE OBSERVATION Humankind has always been fascinated by the movements of heavenly bodies. Many of them can be observed with our own eyes by just simply looking at the sky. The stars and planets have regular orbits. Therefore, their positions can be predicted if one observes them carefully, making annotations from year to year. That is why Astronomy was the first formal science.
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OPTICAL TELESCOPES The earliest known working telescope appeared in 1,608 and is credited to Hans Lippershey. It magnified the image 3 times. Galileo heard of this device in June 1,609 and dedicated himself to its improvement. By 1,610 he built a telescope which magnified 33 times. With this telescope he discovered the satellites of Jupiter and described their movements. He also proved the rotation of the sun on its axis and established the Copernican System, that said that the planets revolved around the sun and not around the earth, as stated by Ptolemy.
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STATE-OF-THE-ART IN OPTICAL TELESCOPES Using very advanced technologies, the Very Large Telescope was built in the Atacama Desert in Chile, chosen by its clean atmosphere. It consists of four individual large telescopes, complemented by four auxiliary ones. It operates at visible and infrared wavelenghts. It lets the operator to detect objects four billion times fainter than what can be detected with the naked eye. It is the most productive ground-based facility for astronomy, with only the Hubble Space Telescope genrating more scientific papers among facilities operating at visible wavelenghts. The following image lets us see the Very Large Telescope:
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NON-VISIBLE LIGHT TELESCOPES When it was discovered that there were many different types of energy that could be detected coming from space, different types of telescopes were built. The following table shows the different kinds of electromagnetic energy that can be detected by telescopes: Name
Wavelength
Gamma ray less than 0.01 nm X-Ray
0.01 to 10 nm
Ultraviolet
10 nm - 400 nm
Visible
390 nm - 750 nm
Infrared
750 nm - 1 mm
Microwave
1 mm - 1 meter
Radio
1 mm - km
CLASSIFICATION BY LOCATION Telescopes can be also be classified by location into Ground Telescope or Space Telescope. In the following pages, several examples will be shown.
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VERY LARGE ARRAY RADIO TELESCOPE Location: Socorro, New Mexico, United States
X-ray Space-based telescope named Einstein Observatory
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Near ultraviolet, visible and near infrared Space Telescope Hubble
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TELESCOPIC IMAGES OF DIFFERENT TELESCOPE TYPES The same heavenly body, seen through different types of telescopes, can give different types of information, giving us a better understanding of the universe. The following collection of images illustrate this. Under each image, the type of energy measured and the name of the telescope is shown.
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OTHER WAYS OF STUDYING THE UNIVERSE Besides looking at the universe, humankind also learns by touching, weighing and sampling the universe. We do that in our daily life, when for example, after looking at a cake, we take a slice, smell and eat it. Following the same principle, the exploration of our universe has progressed by sending spaceships to space, the moon and other planets in manned and unmanned flights.
MANNED FLIGHTS People in space can learn a lot about themselves, materials and the universe. There is no atmosphere to distort the view of space and they enjoy the absence of gravity, allowing them to make many experiments that are impossible on earth. Also, by landing on the moon, astronauts were able to bring samples of lunar soil to earth, giving them the chance of studying them in depth. In the following pages, several images of manned space explorations will be shown.
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Astronaut taking samples of the moon
Scientists making experiments inside the International Space Station floating in space
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Astronauts working on the outside of the International Space Station. A very interesting tour of the inside of the International Space Station can be seen here: http://www.youtube.com/watch?v=doN4t5NKW-k
UNMANNED SPACE EXPLORATION Very important experiments can also be performed by machines that land on other planets, such as the ones sent to Mars. The Phoenix Mars Lander landed on Mars on May 25, 2008 and was designed to study the history of water and habitability potential in the Martian arctic’s
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ice-rich soil. The Mars Science Laboratory’s rover vehicle named Curiosity landed on August 6, 2012. Its mission is designed to assess whether Mars ever had an environment able to support small life forms called microbes.
Phoenix Mars Lander deck after deliveries of several Martian soils samples to instruments. In the center and right foreground is the Thermal and Evolved-Gas Analyzer. On the left is the Microscopy, Electrochemistry and Conductivity Analyzer.
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IMPORTANCE OF ASTRONOMICAL STUDIES We certainly have very urgent problems waiting to be solved on earth, but astronomy is helping us in many ways, so it is not a waste of time. I will mention the main ones: - Our calendar. - Much of today’s mathematics. - Astronomy’s need for computational power drove the development of many of the earliest electronic computers. - The satellite network that gives us communications and other services such as GPS is possible thanks to the fundamental knowledge of gravity and orbits discovered by astronomers. - Image-processing techniques developed by astronomers now are part of the medical imaging systems that allow non-invasive examiation of patients’ internal organs. - In sum, astronomy has been a cornerstone of technological progress throughout history, has much to contribute in the future and offers all humans a fundamental sense of our place in an unimaginable vast and exciting universe.
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