Download The Universe Pluto

ASTRONOMY
PLUTO VIDEO
The Outer Planets – The Universe
Pluto
MURCHISON
1) Cal-Tech professor Mike Brown set in motion a chain of events that reduced the number of planets in the
Solar System from 9 to 8.
2) Pluto is much smaller than the rest of the planets and has the largest moon in proportion to its own size. It
also has the most inclined and ______________________orbit.
3) Purceval Lowell is the man who started the search for Pluto a Lowell observatory. He predicted that there was
a ___________________________ distorting the orbit of the ice giants Neptune and Uranus. Clyde Tombaugh
was the research assistant who discovered Pluto.
4) When Pluto was announced as the ninth planet, some experts argued that Pluto’s mass was too
__________________to perturb the orbit of neighboring gas giants Uranus and Neptune. Scientists have now
realized there is no Planet X. It had been predicted using inaccurate estimates of _____________________mass.
5) Although it was eventually discovered to be smaller than our ___________________, Pluto was originally
thought to be large as Mars.
6) Because of its great distance from the Sun, Pluto takes its name from the Roman god of the ______________
7) Pluto Facts
- At its closest Pluto is _________ billion miles from Earth
- Its diameter is 1,485 miles, ½ the width of the United States
- It takes ____________years to orbit the Sun
- A day on Pluto last 6.4 Earth days
- A 150 person would weigh ________ pounds on Pluto
8) The Hubble Space Telescope is our primary source of information about the surface of Pluto. Even with
limited imagery, astronomers can see light and dark areas on the surface of Pluto. With this information
scientists can measure the composition of Pluto. They believe the bright areas of the surface are made up of
three types of ice
1) carbon monoxide
2) ______________________
3) nitrogen (the same “stuff) as in our atmosphere
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10) Pluto is 30-40 times further from the Sun than Earth which means the sunlight hitting the surface of Pluto is
1000 times fainter than hitting the surface of the Earth. This would be about the same brightness as being under
a dim street light at night.
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9) The dark areas are probably solid rock, more than likely some form of _____________________, the same as
found on Earth
ASTRONOMY
PLUTO VIDEO
MURCHISON
11) Pluto’s distance from the Sun makes it one of the coldest (but not colder than Titan) places in the Solar
System with a surface temperature of ______________oF. Because of its small size and density, gravity on Pluto
is far weaker than on Earth. Pluto’s gravity is roughly 1/15th that of Earth’s.
12) Pluto has scientific value because its surface is more __________________ that any other in the Solar
System. It would provide scientists with a window into the environment of the Solar System when it formed. The
rock on Earth is different because of ______________________. The rock on Pluto is much more ancient,
preserving a more primitive record of the early Solar System.
13) Pluto is probably covered with impact craters. Pluto has no atmosphere, no weather, no ________________,
and no erosion to change the surface.
14) Pluto undergoes a change as it orbits closer to the Sun with the additional heat. Some of the frozen gases
evaporate to form a temporary _____________________. As Pluto recedes from the Sun, the gases freeze again
and fall back down to the surface.
15) Pluto was kicked out the Solar System as a planet
16) Cal-Tech astronomer Mike Brown was seeking out Pluto-sized worlds in the far reaches of the Solar System.
In 2005 he found one, larger than Pluto with its own moon, both orbiting the Sun. Brown originally thought he
had found the 10th planet. The “planet” he discovered is ________ larger than Pluto, probably made of the same
materials; rock on the inside, ice on the outside, with a thin layer of frost on the outside that sometimes defrosts
into a thin atmosphere, very similar to Pluto. The new “planet’s” moon orbits every 17-18 days around it.
17) Pluto has a moon also, but it is almost its twin. Brown originally wanted to name his planet ___________,
after the TV show – Zena: Warrior Princess. Eventually he chose the name Eris, after the Greek goddess of
discord.
18) The discovery of Eris began the discussion concerning the official definition of a planet, meaning either Eris
would become the 10th planet or Pluto-sized objects would be reevaluated as a whole. In 2006 at the _________
conference in Prague, a vote was taken and the term planet was defined scientifically for the first time.
19) Pluto was reclassified due to the discovery of Eris and other Kuiper belt objects. The _______________ belt
is a 3.5 billion mile wide region in the outer Solar System near Pluto. It is home to hundreds of thousands of icy
objects, the first of which was discovered in 1992.
20) The IAU definition of a planet is that it is a spherical object that orbits the Sun and clears out the
neighborhood around its __________________ path. Since the area around Pluto is full of other Kuiper belt
objects, the new definition excludes Pluto from being classified as a planet.
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22) Ultimately, Pluto’s status as a planet is a _________________________ issue rather than an issue of science.
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21) Objects like Pluto and Eris were given the new classification, _________________ planets. Dwarf planets
posses the same characteristics as planets, but do not have a clear orbital path. Under the new definition,
Saures, the largest asteroid in our Solar System is also a dwarf planet.
ASTRONOMY
PLUTO VIDEO
MURCHISON
23) NASA’s New Horizion space craft will be the first mission to study Pluto. New Horizion must travel at warp
speed to study Pluto’s atmosphere or the opportunity to study the atmosphere will be lost for the next 200
years. As Pluto recedes from the Sun, its __________ year winter begins. When winter begins, the dwarf
planet’s atmosphere freezes and falls to the ground. If the atmosphere collapses too much, the scientists will be
unable to determine the chemistry, weather, and make-up of the atmosphere of Pluto.
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24) To get there in time, New Horizons is blazing through space at ___________________ miles per hour or 12
miles per second. It took 6 hours to get to the Moon, Jupiter in 13 months, and 8 years to get to Pluto. It will
arrive in 2015.