Ch. 1 Exploring Space

Transcription

1 Ch. 1 Exploring Space 1.1 Some space objects are visible to the human eye. -For most of history, the only thing we knew about space was what we could see with our eyes or with simple tools. We had to imagine a lot of what was in space. -Although we ve learned a lot in recent years with new technology, there is still so much we don t know. orbit- - causes the arrangement of the universe smallest largest (New Berlin) (Wisconsin) (North America) (Planet Earth) constellation- -constellations appear to move with the night sky; they are but they are so far away that we 1.2 Telescopes allow us to study space from Earth. -EM radiation travels in all directions throughout space -All 7 types of EM waves can be found in space spectrum- wavelength- telescope- -reflecting telescope- -refracting telescope- -radio telescope- -Hubble Space Telescope-

2 1.3 Spacecraft help us explore beyond Earth. -Space travel takes a lot of planning. Everything astronauts will need, they must take. Not just clothes, food, & fuel, but oxygen and their own gravity. satellite- -For about a decade the US and Soviet Union were in a. Russia launched the first to orbit Earth and sent the first human into space. US sent the first. NASA- -NASA s program to reach the Moon was known as the missions -There were Apollo landings between 1969 and Preparations for Moon missions: 1. spacecraft without humans were sent to Moon to see if 2. astronauts were sent into space to -Scientists learned a lot about the Moon s surface and interior from the 380kg (840 lb) of that astronauts brought back to Earth from the Apollo missions. These samples are still being studied today. space station- MIR- (meer) ISS- -US, Russian and 15 other nations are working together to build this space station -it was so big that it was not able to be launched as was, it was sent in pieces and then put together in space -it s about as big as two football fields -construction of ISS began in NASA has launched more than 100 space shuttles since 1981

3 Why travel to the Moon and not other planets? -we don t travel to other planets because they are so far away that it would take years to get there plus the environment of the planets is much too harsh for human survival (some planets don t even have a surface to land on) even if there was a planet with a safe enough environment for humans to explore, it would be very difficult to provide a space vessel large enough to carry everything that would be needed for a trip that would be that far and take that much time but still be small enough to be reasonable to use -for these reasons, we send equipment to explore other planets; this is much safer and much less expensive -we ve sent spacecraft to visit every planet except ; the spacecraft gathers information about the and characteristics of the planet sending it back to Earth along with pictures -these spacecraft have been sent to gather information from other celestial bodies like comets and moons -these spacecraft are guided by sent from Earth -Stages of Space Exploration: Stage 1: flybys- ; it passes the planet quickly so can only gather limited information; a flyby mission can last for a decade Stage 2: orbiters- ; gathers more detailed information of the planet s surface and can identify changes that occur; orbiters may also carry other instruments that measure temperatures, altitude, etc. Stage 3: landers & probes- ; landers actually land on the surface of the planet getting a close up view and gathering info and samples while probes are designed to work for just a short time before they are destroyed by the harsh conditions of a planet s atmosphere; probes gather info about gases in the atmosphere and measure pressure and temp. (probes may not make it to the surface before being destroyed) -best info is gained by a combination of exploratory spacecraft

4 1.4 Space exploration benefits society. -Studying other planets helps teach us about our own planet. impact crater- -One of the most important benefits of space exploration has been the development of. Satellites have allowed us to see what the whole planet Earth looks like. They have improved, shown how Earth s surface is changing, for precise mapping, etc. -In doing space research, we ve developed technology that has been instrumental in. For example, lighter metals have been developed that make wheel chairs much more user friendly. We ve developed computers that can be used for communication by individuals who are able to use only eye movement to control computer commands. Fire retardant (resistant) materials have been developed that help protect firefighters from flame. -In addition, space exploration has opened/developed new fields/technology. Ch. 2 Earth, Moon, and Sun 2.1 Earth rotates on a tilted axis and orbits the Sun. axis of rotation- rotate A=axis revolution- revolve O=orbit season- ; seasons change/occur because of tilt of Earth on it s axis; this tilt determines amount of direct or indirect sunlight shining on Earth which determines the seasons; seasons are not caused by Earth s distance from the sun, they are caused by Earth s tilt and the directness of the Sun equinox- solstice- ; this happens twice a year, in December (winter solstice=shortest day for northern hemisphere) and June (summer solstice=longest day for northern hemisphere)

5 -as we move from winter solstice to vernal equinox you notice days getting longer and nights getting shorter 2.2 The Moon is Earth s natural satellite. -the Moon rotates as it revolves around Earth; both rotation and revolution take about -the Moon orbits the Earth due to gravity, making it a -because the rotation and revolution are the same period of time, we always ; the side we always see is called the near side; the side that always faces away from us is called the far side -the Moon is light colored with the near side having a lot of dark areas and the far side having just a few; light colors are (highlands); darker colors are (maria and craters) mare- (ma-ray) -it is theorized that the Moon formed from when an object hit Earth- parts of the object and parts of Earth broke off to form what is now our Moon -the Moon is about 380,000 km (240,000 mi) from Earth (about the distance between New York and Los Angeles, CA) and is about 4.5 billion years old -the Moon is composed of 3 layers; -the Moon moves about from Earth each year 2.3 Positions of the Sun and Moon affect Earth. -the different views of the Moon are know as phases; there are lunar phases, phases each week -waxing means ; waning means -Moon always waxes from to

6 crescent- 1/4 moon -the phases in order: gibbous- 3/4 moon 1- new moon (we cannot see) 2- waxing crescent (we see 1/4) 3- first quarter (we see 1/2) 4- waxing gibbous (we see 3/4) 5- full moon (we see full face) 6- waning gibbous (we see 3/4) 7- third quarter (we see 1/2) 8- waning crescent (we see 1/4) -the amount of Moon we see from Earth depends on the angle between the Moon and the Sun eclipse- Solar eclipse- Lunar eclipse- umbra- penumbra- -high tides and low tides exist because the Moon s gravity pulls on Earth s oceans; as the Moon revolves around the Earth, the tides rise and fall depending upon how close the Moon is to that part of the Earth Ch.3 Our Solar System 3.1 Planets orbit the Sun at different distances. astronomical unit-(au) ellipse-

7 -all the bodies that orbit the Sun have elliptical orbits -more than 99% of all the mass in the solar system is in the Sun -solar system formed 1- the cloud flattened into a turning disk of whirling material 2- most of the dust fell to center and became a star 3- other dust and frozen gasses stuck together in clumps 4- the dust/gas clumps grew into planets that moved in the same direction as the disk 5- the dust that did not form planets became asteroids, comets, and moons -the planets in order from the Sun Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, (Pluto) -to remember: My Very Energetic Mother Just Sent Us Nine Pizzas. (with Pluto) My Very Energetic Mother Just Sent Us Nachos. (without Pluto) 3.2 The inner solar system has rocky planets. terrestrial- terrestrial planets- tectonics- volcanism- The Terrestrial Planets Tectonics Volcanism Cratering Weathering Moons Orbit Rotation Mercury cliffs lava many broken rock Venus cracks/cliffs lava few little Earth valleys/mnts. many active little much Mars valleys cooled lava many much-wind *hours, days, years for orbit and rotation are Earth time

8 3.3 The outer solar system has four giant planets. gas giants- ring- Jupiter Saturn Uranus The Gas Giants Facts Moons Orbit Rotation largest planet, windy, stormy, clouds rings; outer ring 3x wider than planet spins on its side Neptune a moon moves in opposite direction *hours, days, years for orbit and rotation are Earth time retrograde- 3.4 Small objects are made of ice and rock. -Is Pluto our smallest planet? is Pluto s moon -Pluto is smaller than and Charon is about -Pluto and Charon are called a double planet because: -Pluto s orbit is Earth years and it rotates in Earth days asteroid- comet- meteor- meteorite-

9 Ch.4 Stars, Galaxies, and the Universe 4.1 The Sun is our local star. -the Sun is the star in our solar system -Sun produces E when in its interior changes to (gives off a lot of E in the form of light and heat) fusion- convection- corona- Suns Layers starting with innermost and working to outermost Sun s Interior Sun s Atmosphere 1. - E produced through fusion 4. - visible layer 2. - E travels through radiation 5. - middle layer 3. - E travels through convection 6. - outermost layer sunspot- solar wind- aurora- solar flares- prominences- 4.2 Stars change over their life cycles. -we classify stars by their characteristics like light-year- example: the nearest star outside of our solar system is about 4 light years away

10 parallax- 1. plot the star s position in the sky from opposite side of Earth s orbit 2. use apparent shift in position and Earth s diameter to calculate Earth s distance -most stars appear white but some are bluish or reddish; the different colors are caused by of the stars -stars exist in many different sizes; some are only the size of Earth but others (100 times smaller than our Sun); some, like Betelgeuse, are 600 times larger than our Sun; it s very hard to tell the size of a star because they are -a stars color tells us how hot it is which in turn tells us what its composition is; we classify starts by their color/temp Classification of Stars Class Color Surface Temp ( C) O above 25,000 B 10,000 25,000 A ,000 F G K M below stars don t last forever; they have life cycles; when a star dies some of it may go back to a to form another new star nebula- main sequence- ; this stage can last millions to billions of years: our Sun is a lower-mass star in the middle of its main sequence neutron star- ; they don t emit much light but they do emit a lot of other EM radiation like x-rays black hole- the

11 Life Cycles of Stars first stage final stage -most stars do not exist alone (our Sun is an exception), they are usually grouped 4.3 Galaxies have different sizes and shapes. -Milky Way is shaped like a disk with a bump in the middle (we are in the disk part); the diameter of the Milky Way is more than -there are 3 types of galaxies: Which one is the Milky Way? quasar- -at the center of a galaxy, you will find either a or. Which does the Milky Way have? 4.4 The universe is expanding. -the universe is constantly changing and -some stars that we see through the telescope are so far away that they, it has taken that long for the light to reach us

12 Doppler effect- ; as it moves closer the waves appear to shorten giving the object a blue color, this is known as the blue shift; if the object is moving away, the wavelengths appear to lengthen, giving the object a red color, known as the red shift -galaxies are expanding/moving apart; the farther away the stars are the they are moving apart big bang- ; this happened about years ago; the expansion happened -evidence to support the big bang theory include, the, and other info gathered through experimentation and observation