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209 Cards in this Set
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- Back
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From how long ago do you think we have evidence for the study of astronomy? |
32,000 BC |
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A bone carving dated to the Aurignacian Culture of Europe, c. 32,000 BC is this? |
The oldest marking showing the lunar cycle and its phases. |
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Why would the earliest people want to understand the changes in the night sky? |
To know when to plant crop, curiosity, and to honor their gods. |
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When was it found that people first used the observations of the moon to predict the weather? |
In Central Africa c. 6500 BC |
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Why were the pyramids of Egypt built? |
To pay homage to god and view stellar alignments (tunnels align with stars for viewing). |
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The Pyramids of Giza (c. 2560 BC) are said to align with what stars? |
Orion |
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Who was the goddess of the sky? |
Nut |
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Stonehenge (England c. 1500 BC) had this? |
Many alignments for solstices, equinoxes, and bright stars. |
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Sun Dagger (New Mexico c. 500-1300AD) shows this? |
Noon on summer solstice; other effects in winter and equinoxes. |
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The Mayan observatory, El Caracol, in Chichen Itza Mexico had this? |
Windows placed to allow for observations of Venus (AD 600-1200). |
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Macchu Picchu in Peru (c. 1400 AD) is said to do this? |
Points at the winter solstice sun |
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What is another name for Macchu Picchu and why? |
Hitching Post of the Sun because, at mid day on the equinoxes, the pillar casts no shadow. |
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The Nasca lines in Peru (c. 400-650 AD) are said to represent this? |
Large figures of animals may have represented constellations to the Incas who lived there. |
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The Big Horn Medicine Wheel in Wyoming (AD?) is said to have marked this? |
Months for the Native Americans |
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Ancient Chinese astronomers kept very detailed records of astronomical observations beginning when? |
5,000 years ago |
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Who was the first to record an observations of a Supernova explosion? When? What is it known as today? |
1. Chinese 2. 1054 AD 3. Crab Nebula |
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Who else may have seen the first Supernova explosion recorded? |
The Native Americans in Chaco, AZ |
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What was the life span of Aristotle? |
384-322 BC |
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Aristotle believed this as a first principle? |
The heavens were perfect. |
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Who believed that All motion in the perfect heavens must be caused by the rotation of spheres carrying objects around in uniform circular motion (Earth is center of Universe) |
Aristotle |
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In general ancient astronomers accepted without questions that? |
1. Heavenly objects must move on circular paths at constant speeds. 2. Earth is motionless at the center of the universe. |
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As viewed from Earth the planets seems to follow complicated paths in the sky that include? |
Episodes of "backward" motion that is difficult to explain in terms of motion on circular paths at constant speed. |
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The Earth moves faster along its orbit that the planets that lie farther from the sun. Consequently it periodically overtakes and passes these planets. This is known as? |
Retrograde Motion |
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Around what time was Ptolemy born? |
140 AD |
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Ptolemy set about making an accurate mathematical description of this? |
The motions of the planets. |
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Who believed that the Earth was a little office center and his model slightly varied the planets' speeds. His model was earth centered or "geo-centric". |
Ptolemy |
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What was a problem with Ptolemy's model? |
It was not accurately predicting the position of all the planets over time. --Retrograde motion was hard to reproduce --Had to keep adding smaller epicycles to reproduce planetary motion. |
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What was the life span of Copernicus? |
1473-1543 AD |
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What did Copernicus believe? |
That the Sun was the center of the universe and that Earth rotated on its axis and revolved around the Sun. This is know as the heliocentric model. |
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Had the heliocentric model been discussed before Copernicus? |
Yes |
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Who was the first person to produce a detailed heliocentric model with substantial justifying arugments? |
Copernicus |
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Why did the Copernican model fail to disprove the geocentric model immediately? |
It could not predict the positions of the planets any more accurately that the Ptolemaic model could. |
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What was the lifespan of Giordano Bruno? |
1548-1600 |
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Who proposed that the Sun was a star and that the universe contained an infinite number of inhabited worlds? |
Giordano Bruno |
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What happened to Giordano Bruno because of his theory? |
The Roman Inquisition found him guilty of heresy and had him burned at the stake. |
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What was the life span of Tycho Brahe? |
1546-1601 |
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What are two interesting facts about Tycho Brache? |
1. He word a false nose to hide a dueling scar from his college days. 2. He lived BEFORE the invention of the telescope. |
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This person's observatory was equipped with instruments for measuring the positions of the sun, moon, and planets using the naked eye and sights? |
Tycho Brahe |
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When did the star that became know as "Tycho's Supernova" appear in the sky? |
1572 |
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What did the discovery of Tycho's Supernova show? |
That things could change in the supposedly unchanging starry sphere. Tycho measured it and showed that it had moved far beyond the moon and was changing. |
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Who as a follower of the Copernican hypothesis by 1606 had developed his 3 Laws of Planetary Motion? |
Johannes Kepler |
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The orbits of the planet's around the sun are ellipses with the sun at one focus. This is known as? |
Kepler's first law |
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A line from the planet to the sun sweeps over equal areas in equal intervals of time. This is known as? |
Kepler's second law |
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What speeds up when its close to the Sun and slows down when its far away? |
A planet |
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The two quantities; orbital period and semi major axis are related. This is known as? |
Kepler's third law |
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Oribtal period squared is proportional to? |
The semi-major axis cubed (P2=a3) |
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What is Jupiter's average distance from the Sun? The semi-major axis cubed is? Therefore the period is? |
1. 5.2 AU 2. 140.6 3. The square root of 140.6 or roughly 11.8 years |
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Was Columbus the first to discover the Earth is round? |
No, the Greeks knew. |
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Brahe, Kepler, and Galileo were all alive at the same time as this person?" |
Shakespeare in the 1600's |
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Who invented the telescope? When? Why? |
1. Dutchman Hans Lippershey 2. 1608 3. For seeing ships |
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What was the lifespan of Galileo Galilei? |
1564-1642 |
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Who was the first to use the telescope for astronomy? What did this lead to? |
1. Galileo 2. He fully adopted the Copernican model |
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Galileo observed the following: |
1. The moon is not perfect 2. Four new "planets" circling Jupiter 3. Phases of Venus 4. Stars in the Milky Way 5. Saturn has rings (not a perfect sphere) 6. Sunspots (Sun is not a perfect sphere) |
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How did Galileo calculate the height of the mountains on the moon? |
He used shadows. |
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What are the 4 "planets" that Galileo discovered now known as? |
The Galilean moons of Jupiter |
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Galileo discovered that Venus will only have phases if this is the case? |
Sun is at the center of the solar system |
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What happened to Galileo after he published his observations? |
He was found guilty not of heresy but of disobeying orders given to him in 1616. He was sentenced to life imprisonment and confined to his villa for the next ten years. |
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When did Galileo die? |
January 1642 |
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When did Pope John Paul II first claim Galileo's sentence was a mistake? When did the Vatican declare him a hero of faith and science? |
1. 1992 2. 2008 |
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When was Isaac Newton born? |
Christmas Day 1642 in Woolsthorpe England |
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What is Isaac Newton known for? |
1.Physics 2. Telescope 3. Calculus |
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Newton's 3 Laws relate to? |
The motion of a body to the forces acting on it. |
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A body continues at rest or in uniform motion in a straight line unless acted upon by some force. This is know as ? |
Newton's first law of motion. |
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A body's change of motion is proportional to the force acting on it, and is in the direction of the force. This is known as? |
Newton's second law of motion |
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When one body exerts a force on a second body, the second body exerts an equal and opposite force back on its first body. AKA: Every action has an equal and opposite reaction. This is known as? |
Newton's third law of motion |
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Newton realized that some force must pull the moon toward the Earth's center. Otherwise, it would continue moving in a straight line and leave the Earth forever. This became known as? |
Gravity (Newtonian Physics) |
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Do you have the same mass on Earth as on the moon? |
Yes, but you will weight less. |
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The moon has what proportion of gravity to the Earth? |
1/6th |
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The mass of an object is the measure of? |
The amount of matter-usually expressed in kilograms. |
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Mass is not the same as? |
Weight. |
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The force that Earth's gravity exerts on an object is known as? |
Weight |
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How is weight measured? |
Pounds |
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How is mass measured? |
Kilograms |
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Newton recognized that the force of gravity decreases as the square of the distance b/w the object increases. This is known as? |
Inverse Square Law |
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According to Inverse Square Law, if the distance from Earth to the moon were doubled this would happen? |
The gravitational force b/w them would decrease by a factor of 2 squared, or 4. |
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If we moved the Earth from 1 AU to 2 AU the force of gravity on the Earth from the Sun would be? |
1/4 as much (force is less) |
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An object orbiting earth is doing this? |
Falling (being accelerated) toward Earth's center. |
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Why does an object in a stable orbit continuously miss Earth? |
Because of its orbital velocity. |
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Objects orbiting each other actually revolve around? |
Their mutual center of mass. |
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In order to leave the earth you must have a high enough velocity so it will follow an open orbit. This is known as? |
Escape Velocity (Hyberbolic Orbit) |
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Light is composed of a combination of electric and magnetic waves that can travel through empty space. This is known as? |
Electromagnetic Radiation |
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Unlike sound, light waves do not require a medium and can thus? |
Travel through a vacuum. |
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Electromagnetic radiation is associated with a periodically repeating disturbance that carries energy. This is known as? |
Wave phenomenon |
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Are Radioactivity and Electromagnetic Radiation the same thing? |
NO |
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The distance between peaks of a light wave is known as? |
Wavelength |
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How are wavelength measured? |
1. Nano-meters (10-9m) 2. Angstroms (10-10m) 3. Microns (10-6m) |
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Light waves travel through space at what speed? |
300,000 kilometers per second (186,000 miles per second). This is the speed of all electromagnetic radiation. |
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The number of repeating events per unit time equals? |
Frequency |
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Units are equal to? |
Hertz |
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The longer the wavelength, the smaller the? |
Frequency |
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Although light behaves as a wave, under certain conditions, it also behaves as? |
A particle. |
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A particle of light is called a? |
Photon |
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What is referred to as a minimum-size bundle of electromagnetic waves? |
Photon |
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The amount of energy a photon carries depends on? |
Its wavelength |
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These carry more energy? |
Shorter-wavelength photons |
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These carry less energy? |
Longer-wavelength photons |
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Do light waves travel at the same speed as sound waves? |
No. This why you see the lightening and then hear the thunder. |
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This only makes up a small part of the electro-magnetic spectrum? |
Visible light |
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What is the only part of the electromagnetic spectrum that can been seen? |
Visible light |
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The electromagnetic spectrum consists of? |
Left to right: 1. Gamma Ray 2. X Ray 3. Ultra-violet 4. Visual Light 5. Infrared 6. Microwave 7. UHF 8. VHF 9. FM 10. AM |
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These have different wavelengths? |
The colors of visible light |
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What color has the longest wavelength? The shortest? |
1. Red 2. Violet |
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Our eyes see in the range of what wavelengths? |
400-700 nm |
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This lies beyond the red end of visible range with wavelengths ranging from 700 nm to about 1 mm? |
Infrared Radiation |
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Why don't we glow in the dark? |
People only emit light that is invisible to our eyes. |
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These are used for radar and log distance telephone communications and have wavelengths from about 1 mm to a few cm? |
Microwave transmissions. |
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These have event longer wavelengths than microwave radiation, from a few tens of cm to a few tens of meters? |
Radio waves |
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Electromagnetic waves with wavelengths shorter than violet light are called? |
Ultraviolet |
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Shorter-wavelength electromagnetic waves than UV are called? |
X-Rays |
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The electromagnetic radiation with the shortest wavelengths are? |
Gamma rays |
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The longer the wavelength? |
The less energy. Ex: A radio wave has far less energy than an X-Ray wave. |
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These collect EM radiation over the entire spectrum, from Gamma Rays to Radio? |
Telescopes |
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What are the 3 Main Functions of a Telescope? |
1. Gather More Light (bigger is better) making object appear brighter (MOST IMPORTANT) 2. Resolution (to see fine detail) 3. Magnifaction |
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Objective lens focal length/eye piece lens focal length equals? |
Magnification |
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The ability of a telescope to collect light is known as? |
Light-gathering power |
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The light-gathering power of a telescope is proportional to? |
The area of a primary mirror (the bigger the telescope the more light it catches). AKA the Optical Radius |
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A larger lens provides? |
A brighter, not bigger image. |
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This refers to the ability of the telescope to reveal fine detail? |
Resolving power aka diffraction limit |
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The bigger the telescope the? |
Greater its resolving power at a given wavelength |
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Radio telescopes need to be? |
Larger than optical telescopes? |
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Which telescope has the best resolving power? a. 10 meter infrared b. 10 meter optical c. 20 meter infrared d. 20 meter optical |
20 meter optical |
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The longer the wavelength the worse this is for a given telescope size? |
Resolution |
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What are the two types of astronomical telescopes? |
1. Refracting 2. Reflecting |
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These use a lens to gather and focus light? |
Refracting telescope |
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These use a mirror? |
Reflecting telescope |
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The main lens in a refracting telescope is called the? |
Primary Lens |
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The main mirror in a reflecting telescope is called the? |
Primary Mirror |
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This is used to magnify the image and make it convenient to view through a telescope? |
Eye piece |
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Most telescopes are located where? |
On the top of mountains in protective enclosures. |
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What is the diameter of the largest refraction telescope and its location? |
40 inch diameter. Located at Yerkes Observatory in Williams Bay, WI |
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What two factors can limit resolving factor? |
1. Optical Quality 2. Atmospheric Conditions |
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What is it called when upon viewing Earth through a telescope there is a presence of turbulence in the atmosphere that causes images to dance and blur? |
Seeing |
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What is an example of the effects of seeing? |
Heat waves on asphalt road |
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What makes stars twinkle? |
The Earth's atmosphere |
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A star near the horizon will twinkle more than? |
A star overhead |
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The effect of atmospheric seeing can be removed by a technique called? |
Adaptive optics |
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Rapid computer calculations adjust the telescope optics and partly compensate for seeing distortions through a process known as? |
Adaptive Optics |
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In order for adaptive optics to work we need a bright star--sometimes we have to make one. This is called? |
Laser Guided Adaptive Optics |
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Astronomers build these to gather radio radiation? |
Radio Telescopes |
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This hinders astronomical research? |
The Earth's atmosphere |
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The Earth's atmosphere appears opaque to this? |
Most electromagnetic radiation |
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What are 3 reasons to go to space? |
1. Can observe stars in both N. and S. hemispheres 2. Can escape Earth's atmosphere 3. Wavelengths in the far-ultraviolet, x-ray, and gamma ray ranges are completely absorbed by the ozone layer extending from 20km to about 40km above Earth's surface |
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Optical astronomers avoid cities because of this? |
Light pollution (the brightening of the night sky by light scattered from artificial outdoor lighting). |
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What are some renowned optical/infrared telescopes? |
1. Palomar (San Diego/CalTech) 2. Keck (Mauna Lea, HI) 3. Hubble (put into orbit in 1990, visited 4 times for repairs) |
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The larges radio dish in the work is 300 M (1,000 ft) and it located where? |
Arecibo, Puerto Rico |
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One way to improve resolving power is to connect two or more telescopes in an? |
Interfrometer |
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This has a resolving power equal to that of a telescope as large as the maximum separation b/w the individual telescopes? |
Interfrometer |
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This telescope needs to be cooled down to -269C or -452F? |
Spitzer telescope |
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The largest X ray telescope is? |
Chandra |
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Focusing X-Rays is difficult because? |
They penetrate into most mirrors. |
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What is the largest object in the Solar System? |
The Sun |
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This contains more than 99.85% of the total mass of the solar system? |
The Sun |
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The volume of the sun could not be filled up even if? |
All the planets in the solar system were put into it. |
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110 Earths or 10 Jupiters could fit across the diameter of? |
The Sun |
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The Sun lies where? |
The center of the solar system. It is a star and nearest star to Earth. |
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The sun is powered by? |
Thermonuclear reactions |
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This is a great ball of gas (plasma) held together by its own gravity? |
The Sun |
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The visible layer of the sun is called the? |
Photosphere |
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What is the source of most of the sunlight received by Earth? |
The photosphere |
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What is the depth of the photosphere and its temperature? |
1. 300 miles 2. 5,800 degrees kelvin |
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What is the irregular layer of the sun with a depth on average less than Earth's diameter? |
Chromosphere |
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The core is the very interior which is undergoing this to produce the energy we see as light? |
Nuclear Fusion |
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What is the most familiar form of heat flow? |
Conduction |
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Heat in the form of motion among the atoms is conducted from atom to atom (for example when you hold a spoon over a flame, the heat travels up the handle). This is known as? |
Conduction |
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Infared photons radiated by a flame is the transport of energy known as (ex: feeling on your hand the heat from a candle flame)? |
Radiation |
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The heat-driven circulation of a fluid is known as? |
Convection |
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The 3 ways energy can move in a star: |
1. Conduction 2. Radiation 3. Convection |
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This is carried upward in convection currents as rising hot gas and also as sinking cool gas? |
Energy |
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These lie b/w the core and photospheres? |
Connective and Radiative Zone |
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In the outer core of the corona of the sun the temp. can be |
2 million degrees kelvin or more |
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Just above the chromosphere the coronal temperature is ? The photosphere surface of the sun is? The center (core) of the Sun is? |
1. 500,000 kelvin 2. 5,800 degrees kelvin 3. 22,500,00 degree kelvin (enough for nuclear reactions to occur). |
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These are regions of the photosphere that appear darker than the rest? |
Sunspots |
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These produce less light than equal sized pieces of the normal photosphere and are about 1,000 yo 1,500 degrees kelvin cooler? |
Sunspots |
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These are flamelike jets of gas extending upward into the chromosphere and last 5-15 minutes? |
Spicules |
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This is a bright, gaseous feature extending outward from the Sun's surface, often in a loop shape? |
Prominence aka Coronal Mass Ejections |
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These are responsible for the aurora borealis and can disrupts satellite communications? |
Prominence |
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Gas from the Sun's atmosphere constantly flows along the magnetic fields which point outward and flow away in a breeze called? |
Solar Wind |
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These are produced when gases in Earth's upper atmosphere glow from energy derived by the solar wind? |
Aurora |
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The photosphere is made up of dark-edge regions called? The visual pattern the create is called? How long do they last? |
1. Granules 2. Granulation 3. 10-20 minutes |
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The outermost part of the Sun's atmosphere is called this after the Greek word for crown? |
Corona |
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This is so dim that it is not visible in Earth's daytime sky-because of the glare of scattered light from the sun's photosphere? |
Corona |
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Despite the very high temperature of the corona it doesn't produce much? It also has a low? |
1. Light 2. Density |
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The sun is not considered this due to slowly changing spots larger than Earth and rapid vast eruptions? |
Quiet |
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All solar activity is? |
Magnetic |
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Tremendous energy can be stored in? |
Arches of magnetic fields |
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Magnetic fields are visible near the edge of the solar disk as? and seen from above as? |
1. Prominences 2. Filaments |
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How did Galileo conclude that the sun is rotating? |
By observing sun spots moving across the sun's disk. Causing him to go blind. |
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Sunspots are cool spots on the Sun's surface caused by? |
Strong magnetic fields |
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These follow an 11 year cycle, not only in their number of spots visible but also in their location and are caused by cyclical changes in the sun's magnetic field? |
Sunspots |
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This causes the magnetic field lines of the sun to get tightly wrapped causing protusions that make sunspots and flares? |
Differential rotation (center rotates faster than the poles) |
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After 11 years of tightening due to differential rotation the stress causes a global relaxation of the field which leads to? |
Polarity reversal |
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Compared to Earth's orbit around the Sun... Venus has an orbital period that is? Mars has an orbital period that is? |
1. Shorter 2. Longer |
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Compared to Earth's orbit around the Sun a planet that orbits farther than the Earth has an orbital period that is? |
Longer |
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Compared to the Earth's orbit around the SUn most of the planeets in our Solar System have an oribital period that is? |
Longer |
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If the mass of the Earth somehow increased with no change in radius, your weight would? |
Increase also. |
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What is the difference b/w a solar filament and a solar prominence? |
Same feature, only seen from different perspectives. |
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What are some characteristics of the photosphere? |
1. Temp. of 5800 K 2. Location of granulation 3. Normally visible surface of the sun |
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What are some characteristics of the corona? |
1. Temp. of 1-2 million K 2. Emits X-Rays 3. Visible during an eclipse 4. Irregular in shape |
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These usually appear in groups and are observed on the photosphere? |
Sunspots |
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What causes the Sun's magnetic field to become tangled? |
The Sun does not rotate as a solid body, rotation at different latitudes occurs at different rates, tangling the magnetic field lines. |
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This is a huge release of magnetic energy from the Sun converted into light, heat, and accelerated high-energy particles? |
Solar Flare |
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During this, astronauts in orbit around Earth are subject to much higher doses of radiation than they would normally receive on Earth? |
Coronal Mass Ejection Event |
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Light behaves as a wave when it? As a particle when? |
1. Travels from one place to another 2. Interacts with Matter |
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The distance b/w two crests of an electromagnetic wave descibes? |
Wavelengths |
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The rate at which electromagnetic waves oscillate? |
Frequency |
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What property of reflecting telescope determines its light gathering (or light collecting) power? |
The area of the mirror. |
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Why are radio telescopes bigger than optical telescopes? |
It is necessary to see fine detail of radio waves. |
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Why would several radio telescopes be combined into an interferomenter? |
To decrease the smallest angle which can be observed by the telescope. |
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Angular resolution due to the Earth's atmosphere is limited by? |
Diffraction effects form the telescope's optics. |
