Unit 5: Space Exploration

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1 Unit 5: Space Exploration Topic 1: Our Eyes Only Define FRAME OF REFERENCE: a set of axes of any kind that is used to describe the positions or motions of things Define CONSTELLATIONS: groupings of stars that form patterns, which appear like objects and are given names Define AZIMUTH: is the angle measured clockwise from north when measuring altitude-azimuth co-ordinates Define ALTITUDE: is the angle measured above the horizon in degrees when measuring altitude-azimuth coordinates Define ZENITH: the point directly above (90 degrees) Define EARTH CENTERED MODEL/GEOCENTRIC. Who originally came up with this idea? Who refined it? Based on the ideas of Greek philosopher Aristotle states that the Earth is the center of the universe. It has an outer celestial sphere with many inner spheres. Define SUN CENTERED MODEL/HELIOCENTRIC. Who originally came up with this idea? Copernicus proposed a different model in which the Sun was fixed and a rotating Earth revolved around it. What did some of the ancient civilizations believe about the Universe? Egyptians: Sun god Ra was carried daily through the sky in a sacred boat. Romans: Jupiter was the king of the gods Aboriginals had various stories. Ursa Major was a bear running from hunters Topic 2: Stronger Eyes Define TELESCOPE: is used to magnify objects at great distances and contains an objective lens and an ocular lens. Define OBJECTIVE LENS: the large lends at the front of the telescope Define OCULAR LENS/EYEPIECE: the eyepiece through which you view the magnified object What where the FOUR things Galileo Galilei discover? Which model did this support? He discovered moon blemishes that lead to the Moon having craters and mountains on it. He observed the sun spots moving over the surface which lead to the sun rotating on its axis. He observed Jupiter had moons that orbited it. Lastly he observed that the stars are much farther away than the planets. Who discovered the telescope? Dutch spectacle maker, Hans Lippershey Define RESOLVING POWER: The fineness of detail the telescope can produce of the object in view. What determines the resolving power of a telescope? This depends on the diameter of the objective lens. How does a REFRACTING TELESCOPE differ from a REFLECTING TELESCOPE? Which provides a better image? Refracting telescopes have a lens for their objectives and reflecting telescopes have objective mirrors. Refractors five better images than equal-size reflectors, but reflectors can be made much larger. New designs have elements of both types. Define ELLIPSE: a figure that looks like a squashed circle: planets in the solar system move in elliptical orbits around the sun. How do planets orbit? (what shape): Elliptical Define UNIVERSAL GRAVITATION: Newton s law states that all objects attract all other objects, and provides an explanation fro the planets elliptical orbit. Which model does universal gravitation support? Heliocentric

2 Topic 3: The Spectroscope Define SPECTRUM: A collection of the light waves presented. Who was the first to discover the spectrum? Isaac Newton Define SPECTROSCOPE: a device that produces a focussed spectrum Define SPECTRAL LINES: Dark lines that appear on the spectrum What are the THREE different types of SPECTRA? What do they each produce? (page 377) Emission or Bright Line Spectrum: produces a dark band with lines of color. Continuous Spectrum: Rainbow Absorption or Dark Line Spectrum: A colourful band with dark lines Define SPECTROSCOPY: The study of spectra Define DIFFRACTION GRATING: A device made of thousands of closely spaced slits Define SPECTRAL ANALYSIS: Studying the spectra of objects and determining what they are made of. Define DOPPLER EFFECT: The phenomenon that the observed frequency of a wave changes if the source of the wave and the observer are moving toward or away from one another What is RED SHIFTED? (moving away or toward? short or long waves?) Away: longer waves What is BLUE SHIFTED? (moving away or toward? short or long waves?) Towards: Shorter waves Topic 4: Smarter Telescopes What are the THREE results achieved with advance in technology? Bigger telescopes, Computers and adaptive optics What is the advantage of linking telescopes through computers? By linking images from telescopes using computers, you essentially have created the equivalent of one telescope the size of the total distance between the two. Define ADAPTIVE OPTICS: Computers that control the image you see are always adapting the mirror to changes in the Earth s atmosphere to remove cancel the twinkling effect. Define TRIANGULATION/PARALLAX TECHNIQUE: A method of measuring the distance indirectly to an object by creating an imaginary between an observer and an object whose distance is to be estimated. In triangulation, the BIGGER the baseline, the more accurate the results. Define AU (ASTRONOMICAL UNIT): The distance from Earth to the Sun What is one AU equal to? approx. 150 million km Define LIGHT-YEAR: the distance that light travels in one year. What is one light-year equal to? About AU Topic 5: What Channel? Define ELECTROMAGNETIC RADIATION: Different forms of waves including radio waves, microwaves, infrared radiation, visible light, UV light, X-rays and gamma rays. Define RADIO ASTRONOMY: Using radio ways to learn about the composition of stars Where do radio waves come from? From radio objects like the planets and stars Define RADIO OBJECTS: objects that emit radio waves. The louder the radio object, the brighter it is.

3 What is a radio dish? Also known as Radio Telescopes that collect radio waves How do radio astronomers see using radio waves? What do the colours mean? (page 395) Astronomers monitored and recorded the incoming radio waves. Then they graphed a data. Today computers store the same data and false colour it to produce images of the radio waves. Define INTERFEROMETRY: If two or more radio telescopes are separated by some distance but are connected electronically their signals can be combined using a computer. The resulting images are as good as if one telescope were used that was a big as the distance between the two. Define VERY LONG BASELINE INTERFEROMETRY (VLBI): Connecting telescopes WITHOUT wires. Topic 6: Above the Atmosphere and Under Control Define a ROCKET: A tube that contains a combustible material and a payload Define PAYLOAD: the device or material that the rocket carries (person, equipment, explosive) Define EXHAUST VELOCITY The speed at which exhaust leaves the rocket. Liquid fuel has a faster exhaust velocity than solid fuel. What are the THREE basic parts of a rocket? What is each part responsible for? The structural and mechanical elements: everything from the rocket itself to engines, storage tanks and fins The fuel The payload What is the difference between an artificial satellite and a natural satellite? What is an example of each? What can artificial satellites be used for? A artificial satellite is a device that is made by humans and orbits. A natural satellite occurs naturally ie. The moon. Artificial satellites are used for communication, entertainment, Remote sensing. What are some of the things computers are responsible for in relation to rockets/spacecrafts? Computers figure out gravitational assist, improve what we see with CCD s, and combine, analyze and synthesize data. Define GRAVITATIONAL ASSIST: A method of acceleration which enables a spacecraft to gain extra speed by suing the gravity of a planet. The craft is sent around one planet. The planet s gravity attracts the craft causing it to speed up and change direction. At times it can cause the object to slow down, but puts it in a new trajectory. What are CCDs/CHARGE COUPLED DEVICES?: These devices convert light signals into electric signals in digital format. What is a GEOSYNCHRONOUS orbit? Where are these satellites placed? What can they observe? What are they usually used for? Objects in this orbit move in the same direction as Earth rotates. These are about km above Earth, directly over the equator. Radio and television are usually in geosynchronous orbit. What is LOW EARTH ORBIT? Where are these satellites placed? What can they observe? What are these satellites better at transmitting than geosynchronous satellites? These satellites are placed km high above the ground and complete one complete orbit in about 1.5 h. Telephones are in this orbit. What are the names of two Canadian satellites? Anik and Anik E2

4 What is REMOTE SENSING? What are some applications of it? The science of taking measurements of Earth and other planets from space. Used to see Healthy vs. Unhealthy vegetation Clear-cut and burned forests Water pollution Erosion Land use in cities Weather tracking What is GPS? What does it use to determine location? How many satellites are there in orbit, and at least how many are above the horizon? Global positioning system. Used to determine where a specific location is on Earth. There are 3 above the horizon, wherever you are, whatever time of day km above Earth. Topic 7: The Solar System Up Close What is the Sun mostly composed of? How many times is it bigger than Earth? The sun is mostly hydrogen. It is 110 times the diameter of Earth What are Sun spots? The regions of the sun that are cooler and therefore appear to be darker than their surroundings. What is SOLAR WIND? Outflow of high-energy subatomic particles into space. What protects Earth from solar wind? The Earth s magnetic field protects us from the harmful effects of the solar wind. How is energy released from the Sun? Nuclear Fusion (hydrogen being converted into helium) What are the INNER PLANETS? What are they composed of? Also known as terrestrial planets- Mercury, Venus, Earth and Mars What are the OUTER PLANETS? What are they composed of? These planets have gaseous composition and are Jupiter, Saturn, Uranus and Neptune Life cycles of stars (massive and Sun-like). Sun like star: Start with stellar Nebula-à Average star à Red Giant à Planetary Nebula à White Dwarf à Black Dwarf Massive star: Stellar Nebula à Massive Star à Red Supergiant à Supernovaà if the star is not destroyed entirely the core is left as a Neutron Star or Black Hole Distribution of matter in space. We live on the planet Earth which has a moon that orbits us. We orbit the sun (a star, and one of many in our galaxy). Other planets orbit the sun as well. All of these are part of the Milky Way Galaxy, which is one of billions of galaxy s. What is a GALAXY? A galaxy is a grouping of millions or billions of stars, gas and dust. It is held together by gravity. Topic 8: People in Space How fast must an object travel to escape Earth s gravity (in km/h)? kmh or 8km/s Who were the first humans on the Moon? When did they arrive? What was their mission called? Neil Armstrong and Edwin Aldrin were the first humans on the moon and they were part of the Apollo program (#11) that also included Michael Collins. What is a SPACE SHUTTLE? How is it different from an ordinary space craft? The Space Shuttle is a reusable spacecraft.

5 What is the ISS (INTERNATIONAL SPACE STATION)? How many nations are involved? This project involves 16 nations and is the largest and most complex international scientific project. It will provide a orbital laboratory for long term research where gravity is effectively reduced. What is one major Canadian contribution to the ISS? Canadarm and Canadarm 2 What is MICROGRAVITY? This term is used instead of zero gravity because there is almost as much gravity in orbit as there is on Earth. Weightlessness occurs because orbiting has the same effect as falling. What are some of the changes the body undergoes in conditions of weightlessness? Astronauts and Cosmonauts experience weakened muscles (atrophy or deterioration) because they are not battling gravity to move their muscles. What are some Space Age inspired materials and systems? (table at the end of Topic 7)