Exam 1 Flashcards
If astronomers near Onion Nebula were able to see Earth clearly, what would they see? Why?
a tiny, pale blue dot against the backdrop of a much brighter, expansive nebula.
What kind of stars did Edwin Hubble use as standard candles to determine the distance galaxies?
Cepheid Stars
What do we call the earliest time in our Universe when it was very dense and very hot?
Big Bang
What proof exists of a young hot Universe?
Cosmic microwave background
Where are elements heavier than iron formed?
Stars, form during supernova explosions, death of massive stars
What percent of the solar nebula out of which the Solar System formed ended up in the Sun?
99.8%
Why are the planets that formed closer to the Sun composed primarily of silicates and iron compounds?
Too hot to hold the volatile gases that dominate the solar nebula
Why are the planets in the outer solar system so large?
Large size, large gravitational attraction (accelerates growth). They captured a large amount of hydrogen and other gases from the surrounding nebula with their enormous gravity
How do we explain the large exoplanets orbiting close to their stars that we have found?
migration
What features of the Solar System can be explained as a consequence of the Grand Tack Hypothesis
Small mars, asteroid belt, no super earth, no hot Jupiter
What features of the Solar System can be explained as a consequence of the Nice Model?
How the outer planets came to their present orbits, how the trojan asteroid in the outer solar system came into their orbital configurations. The migration of the outer planets caused instability among small bodies
What does the word planet mean?
Wanderer
How did the Ptolemaic Model explain retrograde motion?
Epicycles, circling the planet but circles the circle, used for 13 centuries
Who gave us the three laws of planetary motion?
Kepler
What is eccentricity?
It tells you how stretched out the orbit is
Who demonstrated that Kepler’s Law are a consequence of his theory of gravity?
Isaac Newton
What criteria must be met for an object in the Solar System to be called a planet?
Orbits the sun, nearly round shape, has cleared its orbit
What event involving Venus was used to determine the length of an astronomical unit?
the transit of venus
What planet has the greatest orbital speed?
Mercury (88 Earth Days)
Why do the Moon and the Sun have the same angular size in the sky?
The sun is about 400 times farther away from Earth than the Moon and is also 400 times larger than the Moon
Which planet has the highest densitty?
Earth
Which planet has the lowest density?
Saturn
Which planet has the highest albedo (brightness)?
Venus
What is obliquity?
The angle between a perpendicular to its orbital plane and its spin axis - the tilt of its axis
Which planet has the shortest synodic day?
Mercury, 116 days
Which planet has the longest sidereal day?
Venus, 243 days
What are requirements for a planet to have a global magnetic field?
The interior region of electrically conduction fluid, convection in that layer, moderately rapid rotation
Which planet has the most moon?
Saturn
What is velocity?
Speed and direction of motion
What is acceleration?
Change in velocity, increase, decrease or change in direction
What is force?
a push or pull
What is mass?
the amount of matter in an object
How can we tell if a net force is acting on an object?
Any change in the objects state of motion
Does the Moon accelerate as it orbits the Earth?
Yes, gravity makes the moon accelerate all the time
How is the force of gravity affected if the mass of one of the objects is doubled?
The force of gravity between them is doubled
How is the force of gravity affected if the distance between the two objects is doubled?
Reduce to 1/4 of the initial force
Describe how to put a cannon ball into orbit.
firing it horizontally from a mountain so high that its peak is above the Earth’s atmosphere
What is the barycenter of two objects?
Common center of mass
Why does the Sun wobble in space?
As the sun orbits this moving barycenter, it wobbles around
What are gravitational assists and how are they used in space exploration?
Interaction with a planet is used to change the speed and trajectory of a spacecraft
Why are gaps found in the asteroid belt?
Caused by the orbital resonances between Jupiter and the asteroid belt
What is a chaotic orbit?
An orbit that can change in a largely unpredictable manner or one where a tiny change in the position and/or velocity of the orbiting body will produce major changes in the orbit
How much more light gathering power does an 8-inch telescope have compared to a 4-inch telescope?
4 times the amount
What is resolving power?
ability to discern details
What is the purpose of adaptive optics?
To correct for distortions in light waves caused by atmospheric turbulence
How does adaptive optics work?
Measuring the distortions in a wavefront and then using a deformable mirror to change its shape and compensate for those distortions
What advantages does the Hubble Space telescope have over telescopes located on the surface of the Earth?
There is less distortion from atmospheric turbulence resulting in a clearer view
Why can you see more stars in rural areas than in urban areas?
There is less light population
What are the advantages of a bigger telescope?
Bigger telescopes can capture more light and have higher resolution
Why are there no X-ray telescopes located among the Mauna Kea observatories?
X-radiation is absorbed by the Earth’s atmosphere, preventing X-rays from reaching the Earth’s surface
Where is the Extremely Large Telescope located?
Chile
Where is Gemini North located?
Hawaii
Where is Gemini south located?
Chile
Where is Gran Telescopio Canarias located?
Canary Islands
Where is the Hobby-Eberly Telescope located?
Texas
Where is the Hubble Space telescope located?
Leo (lower earth orbit)
Where is the James Web Space Telescope Located
L2
Where is the Keck Telescope located?
Hawaii
Where is the Large Binocular Telescope located?
Chile
Where is the Subaru Telescope located?
Hawaii
Where is the Southern African Large Telescope (SALT) located?
South Africa
Where is the very large telescope located?
Chile
What makes Mauna Kea a near ideal location for observation?
high elevation, dry atmosphere and dark skies
Which of the largest telescopes in the world are located on Mauna Kea?
The keck telescope, Subaru Telescope and Gemini North
Which observatories on Mauna Kea were part of the Event Horizon Telescope that produced the first image of a black hole?
The submillimeter array and the James clerk maxwell telescope (JCMT)
What is the approximate baseline of the Event Horizon Telescope?
12,700 kilometers? The span of the entire Earth?
Which observatories are apart of the event horizon observatories?
ALMA
APEX
James Clerk Maxwell Telescope
Large Millimeter Telescope
Pico Veleta Observatory
South Pole Telescope
Submillimeter Array
Submillimeter Telescope
Where is ALMA located
Chile
Where is APEX located?
Chile
Where is the James Clerk Maxwell telescope located?
Hawaii
Where is the Large Millimeter telescope located?
Mexico
Where is the Pico Veleta Observatory located?
Spain
Where is the South Pole telescope located?
South pole
Where is the submillimeter array located?
Hawaii
Where is the Submillimeter telescope located
Arizona
Which observatory is the largest array in the Event Horizon Telescope?
ALMA
Which is the most northern observatory in the Event Horizon Telescope?
Pico Veleta Observatory
Which is the southern most observatory in the Event Horizon Telescope?
South Pole telescope
Which observatory has the largest telescope in the Event Horizon Telescope?
Large Millimeter Telescope
Which observatory in the Event Horizon Telescope is located at the highest elevation?
APEX
At what wavelength did the Event Horizon Telescope make its observations?
1.3 mm
In what month in 2017 did the Event Horizon Telescope make its observation of M87*?
April
How were the telescopes in the Event Horizon Telescope synchronized?
Atomic Clocks
How much total data was collected by the Event Horizon Telescope to produce the first image of a black hole?
5 petabytes or 5,00 terabytes
How was the Event Horizon Telescope data brought together?
flown by FedEx
What caused a six month delay in sending the data from one of the Event Horizon Telescope observatories?
The winter weather in the south pole was too harsh to fly in and out of. No flights were in or out from february to october
What is the name of the black hole at the center of our galaxy?
Sagittarius A*
How does the mass of the black hole at the center of our galaxy compare to the mass of M87*?
M87* is 1,000 times more massive
How does the size (diameter) of the black hole at the center of our galaxy compared to the size of M87*?
M87* is 1,000 times bigger
Why does the black hole at the center of our galaxy appear to be the same size in the sky as M87*?
M87* is 1,00 times further away so they appear the same size
How does our Moon rank in size compared to other moons in the Solar System?
Ours is the 5th largest moon in the solar system
How does the diameter of the Moon compare to the diameter of the Earth?
The moon is 1/4 the size of the Earth
How much later does the Moon rise and set each day? Why does it do this?
50 minutes later each day because it moves eastward 12 degrees as it orbits the Earth.
How many times does the Moon rotate during one orbit of the Earth
Once
Why do we see the Moon go through phases?
Seeing part of the day side and night side of the moon. As it orbits earth different parts are illuminated by the Sun
Who can see a lunar eclipse?
half the earth
Who can see a solar eclipse?
A narrow path
What causes an annular eclipse?
When the moon passes between the Earth and the Sun but doesn’t completely cover the sun
What phase is the Moon in when a solar eclipse occurs?
New moon
What phase of is the Moon in when a lunar eclipse occurs?
full moon
Why don’t we have an eclipse every month?
Eclipse season sifts about 20 days each year
When is the next total solar eclipse in Logan?
June 24, 2169
What is regolith?
A layer of loose, broken rock, dust and other materials that covers the surface of the moon
What causes regolith?
Continuous impacts of meteoroids and charged particles from the sun and stars
What is the cause of nearly all the surface features of the Moon?
impact of asteroids, meteoroids and comets
How did the Moon form?
The violent birth theory. The moon is made up of debris left over following a collision between earth and a body around 4.5 billion years ago
What is escape velocity?
The lowest velocity which a body must have in order to escape the gravitational attraction of a particular planet
Could a single stage rocket achieve Earth’s escape velocity?
If it is going 11 km/s or 25,000 mph
Did the Space Shuttle use liquid or solid rocket engines?
A combination of both liquid and solid rocket engines
What was the first artificial satellite?
Sputnik 1
Which spacecraft gave us the first look at the farside of the moon?
Luna 2 (1959)
Who was the first man in space?
Yuri Gagarin (1961)
Who was the first woman in space?
Valentina Tereshkova (1963)
Who was the first American in space?
Alan Shephard (1961)
Who was the first American to orbit the Earth?
John Glenn (1962)
Which was the first manned mission to orbit the Moon?
Apollo 7
Which mission first landed humans on the Moon?
Apollo 11
During which mission did astronauts visit the Surveyor 3 lander?
Apollo 12
Which Apollo mission was regarded as a successful failure?
Apollo 13
Which mission did an astronaut hit two golf balls on the Moon?
Apollo 14
Which mission did astronauts first use a lunar rover?
Apollo 15
Which mission was the first to land a geologist on the Moon?
Apollo 17
Who was on apollo 11?
Neil Armstrong
Michael Collins
Buzz Aldrin
Which 3 telescopes look the same and are all around 26 ft?
Subaru and Gemini north and south
Which telescope has 4 big circles that are all 29.9 ft?
Very Large Telescope
Which 2 telescopes look the same and are both 91 segments?
Hobby-Eberly Telescope and SALT The HET is 2 ft bigger
Which telescope is just one small circle that is 7.8 ft?
Hubble Space Telescope
Which telescope is 2 circles that are 27.9 ft?
Large Binocular Telescope
Which telescope is 2 large arrays that are 32.8 ft and 36 hexagonal segments?
Keck
Which has 18 hexagonal segments?
James Webb Space Telescope
Which has 36 hexagonal segments and is only one array?
Gran Telescopio Canarias
