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Notes on video lecture:
The Milky Way and Its Black Hole
Notes taken by Edward Tanguay on March 8, 2016 (go to class or lectures)
Choose from these words to fill the blanks below:
heavier, lag, massive, 12, Centauri, four, flashes, Selenological, past, 16, quickly, 1500, gas, outside, JAXA, time, 28, Moon, 384, 2007, staggering, black, mirror, seconds, heavy, Minerva, minutes, million, 375
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as you look far away in the universe, you are looking into the         
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International Space Station
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only very recent that humans have developed technology to have a station                the earth
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floating above the Earth at an altitude of        kilometers
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the diameter of the Earth is     ,000 kilometers
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suggests that moving out away from the Earth is not a very easy thing to do
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travel to the moon
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      ,400 kilometers
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Kaguya
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nickname for SELENE (                           and Engineering Explorer)
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launched on September 14,         
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picture:
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went to the other side of the moon
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took pictures of Earth rise
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because distances are so large in space, we use          to describe how far away objects are
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light takes 1.3 seconds to reach the         
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Moon is 1.3 light-seconds away
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the Apollo astronauts put a              on the Moon
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we can shoot a laser to it and it returns 2.6                later
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Sun
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1.5 10^8 kilometers away
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8.3 light-               away
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Hayabusa
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an unmanned spacecraft developed by the Japan Aerospace Exploration Agency (        ) which returned a sample of material from a small near-Earth asteroid named 25143 Itokawa to Earth for further analysis
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20 light-minutes away from the Earth (more than two times the distance to the Sun)
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the command sent to the probe to deploy the                lander arrived to late, since it took 20 minutes to get there
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there is a 40-minute        for making decisions of how the probe should interact with its environment
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it had to decide as much as it could on its own
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Neptune
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         light-hours away
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Voyager
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human-made object that is the farthest from Earth
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    -light-hours away
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we are still communicating with it
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closest star
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Proxima                 
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4.2 light-years
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Voyager will have to travel for over 10,000 years to get to Proxima Centauri
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Milky Way galaxy
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we are in a galaxy which is a disc and when we look at the Milky Way we see the disc from the inside
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we are     ,000 light-years away from the center of the galaxy
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it's only          light-years thick
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our solar system is revolving around the center of the our galaxy
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at a speed of 220 km/s
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something is pulling us to the center of the galaxy
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we know this to be a            hole
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with infrared light we can see through the dust and debris in space to see the motion of stars at the center of the galaxy
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something is pulling a star, and after it passes through, it speeds on               
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it takes 20 years for a star to orbit around this very            object
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by studying the motion of these stars, you can determine how                the object is
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the answer is                     : the object in the middle of the Milky Way galaxy is four million times heavier than our Sun
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nothing can be that heavy except for a black hole
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black hole at center of the Milky Way
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four                times our solar mass
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other galaxies have                black holes
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it can consume objects including        around it
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even the speed of light is not enough to escape the force of gravity from the black hole
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just before gas enters the black hole, it                in light
The Milky Way and Its Black Hole