The Universe & its Origin

1. The Universe & its Origin Year 10 Science 2010

2. Space Words • Universe • Origin • Pulsating • Expanding • Astronomer • Telescope • Electromagnetic • Refractive • Observatory • weightlessness • Asteroid • Parallax • Centauri • Zodiac • Constellations • Celestial • Galaxy • Supernova • Spectrum • Nebula

3. Components of the universe • From our observations of the night sky we can conclude that the sky is a crystal clear sphere which rotates, carrying with it constellations • Other components include: • Planets • Our Sun and Moon • Meteorites • Comets • The development of the telescope in the 16th century allowed Earth bound astronomers to see objects in the sky with much greater precision than ever before.

4. Our Solar System Eris is the largest dwarf planet in the solar system and is the largest object found in orbit around the Sun since the discovery of Neptune and its moon Triton in 1846. It has a diameter between 2,400 and 3,000 kilometres and is 27% more massive than Pluto.

5. Galaxies A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust. Historically, galaxies have been categorized according to their apparent shape Spiral Elliptical Irregular

6. History of Astronomy • Out of this World! • What was Ptolemy’s view of the universe? • When did he put forward his view? • Who else shared this view? • How did he come up with this idea • What planets had been discovered? • Moving Heaven & Earth • Who is this article about? • What was his theory? • Why did he choose not to publish his work? • When did he come up with his ideas? • Keplar Cracks it! • What 2 things did Keplar discover? • When did this occur? • What did his discovery allow us to do? • Galileo • Why was Galileo on trial? • What did he use to observe th sky? • What did he observe? • What did his observations convince him of? • Death of a scientist • What did Newton discover? • How did he make this discovery? • What did he use his discovery to explain?

7. The Big Bang Theory • The Big Bang Theory assumes that about 12mya a very condensed form of matter exploded causing matter to travel rapidly outward

8. The Doppler Effect • The universe is expanding – scientists have determined this due to the Doppler Effect. • The Doppler Effect is change in wavelength and pitch of sound or change in wavelength and colour in light. • When a star is moving away, the light from the star is of a lower frequency than usual. It moves into the redder frequencies – red shift • When a star is moving towards us, the light from the star is of a higher frequency than expected. It moves into the violet frequencies – violet shift.

9. Other ideas Aboriginal dreamtime In the beginning the earth was a bare plain. All was dark. There was no life, no death. The sun, the moon, and the stars slept beneath the earth. All the eternal ancestors slept there, too, until at last they woke themselves out of their own eternity and broke through to the surface. When the eternal ancestors arose, in the Dreamtime, they wandered the earth, sometimes in animal form -- as kangaroos, or emus, or lizards -- sometimes in human shape, sometimes part animal and human, sometimes as part human and plant. Two such beings, self-created out of nothing, were the Ungambikula. Wandering the world, they found half-made human beings. They were made of animals and plants, but were shapeless bundles, lying higgledy-piggledy, near where water holes and salt lakes could be created. The people were all doubled over into balls, vague and unfinished, without limbs or features. With their great stone knives, the Ungambikula carved heads, bodies, legs, and arms out of the bundles. They made the faces, and the hands and feet. At last the human beings were finished. Thus every man and woman was transformed from nature and owes allegiance to the totem of the animal or the plant that made the bundle they were created from -- such as the plum tree, the grass seed, the large and small lizards, the parakeet, or the rat. This work done, the ancestors went back to sleep. Some of them returned to underground homes, others became rocks and trees. The trails the ancestors walked in the Dreamtime are holy trails. Everywhere the ancestors went, they left sacred traces of their presence -- a rock, a waterhole, a tree. For the Dreamtime does not merely lie in the distant past, the Dreamtime is the eternal Now. Between heartbeat and heartbeat, the Dreamtime can come again.

10. Our Sun • Like all the other planets in our Solar System, the Earth revolves around a medium-sized star. This star provides all the energy necessary to sustain life on Earth. • Our Sun is not unique in the universe. It is a common middle-sized yellow star which scientists have named Sol. This is why our system of planets is called the Solar System. There are trillions of other stars in the Universe just like it. Many of these stars have their own systems of planets, moons, asteroids, and comets.

11. What is a star? • Stars are gaseous objects in space that give off light and heat. They are mainly made of hydrogen and helium. • Our sun is 80% H, 19% He and 1% other elements such as B, C, N • The enormous size of a star creates huge gravitational forces which squeeze the atoms of gases together and create immense pressure and heat. • Our sun is 1million times the size of the Earth and one of the largest stars, Canopus is 80 000 times the size of our sun • In the core of the sun, hydrogen nuclei fuse and release energy – nuclear fusion. • In our sun 655mill tonnes of H is fused to form He every second. The 5 million tones of H used up releases 4.5 x 10 26 joules of energy every second

12. Constellations • Many stars form recognisable patterns called constellations • People of many cultures have given names to many constellations, however most astronomers use the ancient Greek classification. • Their are 88 recognised constellations

13. Light from Stars • Some stars appear brighter than others and they are not all the same colour. • The colour and brightness of a star can be used to determine its size and life expectancy • Astronomers are able to estimate the surface temperature of a star by measuring the wavelength of light given off. • Hottest stars are white to blue, while the coolest stars are red • The amount of light given off (brightness) by a star is determined by the size or mass of the star.

15. Type & Size of stars • YouTube - Star Size Comparison HD • PROTOSTARS • This is a baby star at the earliest observable stage of formation. Although the star is forming from interstellar gas, it is not yet hot enough for nuclear reactions to start in its core. • DWARFS • Our Sun is a dwarf star. Throughout their lives, stars go through many phases of expansion and contraction. When they are a normal size for their weight they are called 'dwarfs'. • Brown dwarfs are failed stars that never heated up enough to explode into a normal star • White dwarfs are dying stars that are slowly burning away the last of their fuel. • black dwarfs - non-luminous dead stars. • SUPERGIANTS • Giant stars have luminosities reaching 1000 times that of the Sun and are up to 200 times as wide. • The largest stars are called supergiants. The biggest ever found is 10 million times as bright as the Sun.

16. Birth and Death of Stars • The stars we see at night have not always been there. Stars are born and die all the time. In fact some of the stars we see may already be dead!

17. HR diagram • The Hertzsprung-Russell diagram plots the absolute brightness against its surface temperature (colour) • Developed by 2 astronomers • EjnarHertzsprung (Denmark) • Henry Norris Russell (America) • When most stars (including our sun) are plotted they fall within the main sequence. The mass of the star determines where it will be found on this section: • Low mass stars tend to be cooler and less bright than high mass stars • Other types of stars fall outside this main sequence. They include: supergiants, giants, and white dwarfs

18. Technology in Space Space Technology is helping us to understand what is beyond Earth. It has already helped us a great deal and we are always discovering more because of it. If we didn't have space technology we might still think that the Earth is flat. Here are some examples of space Technology that have helped us to understand more in the world: refracting and reflecting telescopes  spacecrafts space probes aircrafts types of satellites (low Earth orbit, remote sensing, weather, military, etc.) space shuttles space medicine Space suits

19. Telescopes Electromagnetic Radiation • What is electromagnetic radiation? • The light you see with your eyes is called • The distance between the crest of one wave and the crest of the next wave is called a(n) _______________________ • A range of light of different colours and different wavelengths is called a(n) ________________________. • What colours form the spectrum of visible light? • What wavelengths are included in the electromagnetic spectrum? Types of Telescopes • What do telescopes collect and focus? • What is a convex lens?

20. Telescopes How is a radio telescope different from both a refracting and a reflecting telescope? How is a radio telescope similar to both a refracting and a reflecting telescope? 6. Which telescope uses convex lenses? 7. The largest visible light telescopes are now all ________________________. Observatories 1. A building that contains one or more telescopes is called a(n) _________. 2. Why have astronomers built the largest optical telescopes on the tops of mountains? 3. Why have astronomers placed telescopes in space? 4. Why can the Hubble Space Telescope make very detailed images in visible light?

21. Where have we been? Choose one of the top 10 missions and report back to class: • Voyager 1 & 2 (1977) • Viking 1 & 2 (1975) • Galileo (1989) • Cassini-Huygens (1997) • Magellan (1989) • Venera 9 (1975) • Mars Rovers (2003) • Pioneers 10 & 11 (1972/3) • Near Earth Asteroid Rendezvous (1996)

22. Why study Space? 1) To satisfy our inner curiosity to learn. 2) To learn about atoms and molecules and how they interact and their distribution amounts throughout the Universe. 3) To learn about other planets so that we can better understand what Earth has in common with them and what the differences are. Understanding how other planets and objects formed helps us to understand better how Earth was formed. 4) To understand what the Sun is made of and how it works. To compare stars to our Sun to find out the similarities and differences. We can use this information to help determine how old the Universe is and how the Universe may have begun. To find out how old our Sun is and how our Solar System may have formed and the expected life cycle of our Sun. To learn about the cycles of our Sun to predict sunspot activity and protect our satellites from damage. 5) We learn about what asteroids and comets are made of and the orbital paths of them to protect our planet from any potential deadly impacts. 6) To learn how to safely explore space. To develop manned and unmanned craft to travel through space or to land on planets or moons or asteroids or how to put satellites into orbit around Earth. 7) Studying space has it's own rewards in returning technology to the public. Computers, medicines, medical technology, engine modifications, advances in research, Microcomputers, air filters, water purification systems , the list goes on and on. 8) Satellites can monitor deforestation rates, invasive species progression, ozone depletion and even find the sources of all these problems 9) With the microgravity and complete vacuum properties, we are able to conduct many different experiments that we cannot do here on earth. I.e. cardio vascular experiments Boeing: Space Exploration - NASA Explores. Humanity Benefits.

23. Should we cut NASA funding? • Should we cut NASA funding? - The Tech • Read the above article • Write a letter back to Keith Yost supporting or arguing against him. Justify your response using referenced information from the net.