![Page 1: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/1.jpg)
55
The Solar SystemThe Solar System
A planet by any other name ….
![Page 2: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/2.jpg)
55
Six Planets
What is the Solar System?
• Answer: The system of objects in the solar neighborhood (near the Sun)
• What are these objects?
One Star
Nine Planets
Dozens of moons
Thousands of asteroids
Trillions of comets
![Page 3: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/3.jpg)
55
Discovered Planets
• All planets through Saturn known since the ancients – all you have to do is look up to see them
• Uranus in 1781 by William Herschel– “Georgium Sidus” after George III of
England
• Neptune in 1846 by Johann Galle using predictions by Urbain Jean Joseph Leverrier and John Couch Adams
• Pluto in 1930 by Clyde Tombaugh at Lowell Observatory
![Page 4: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/4.jpg)
55
Planets
• The first step to studying planets?• Compare and contrast• What are important
quantities?• You have:
– A stick– A tree– A car– A house
![Page 5: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/5.jpg)
55
Planetary Properties
![Page 6: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/6.jpg)
55
Concept Test
• Which of the following is a true statement about density?a. A stone and a boulder have the same
density.b. A bowling ball and a soccer ball have the
same density.c. A boulder has a higher density than a
pebble.d. A soccer ball has a higher density than a
billiard ball.e. None of the above.
![Page 7: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/7.jpg)
55
Density and Mass
• What is mass?– Mass is similar to weight, it measures how
much stuff an object is made of– Example: A bowling ball and a soccer ball
are about the same size, but have different masses
• What is density?– Density is mass per volume. It helps to tell
you what kind of stuff an object is made of– Example: A log and a tree have different
masses (and sizes), but the same density because they are made of the same stuff
![Page 8: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/8.jpg)
55
Terrestrial Planets
• Close to the sun• Small
– Mass– Radius
• High density– Primarily rocky– Solid surface
• Weak magnetic field• Few moons• No rings
![Page 9: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/9.jpg)
55
Terrestrial Planets
![Page 10: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/10.jpg)
55
Inte
riors
![Page 11: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/11.jpg)
55
Jovian Planets• Far from the sun• Large
– Mass– Radius
• Low density– Primarily gaseous– No solid surface
• Strong magnetic fields
• Many moons• Many rings
![Page 12: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/12.jpg)
55
Jovian Planets
![Page 13: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/13.jpg)
55
Interiors
![Page 14: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/14.jpg)
55
Orbits
![Page 15: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/15.jpg)
55
Planetary Rings
• All the “Jovian planets” have rings
• These are not solid, but composed of millions of tiny particles of ice and dust
• Rings have structure: gaps and spokes
Composition
Size
Jupiter Dust Small grains
Saturn Water ice < house size
Uranus Carbonaceous
Large particles
Neptune
dark, unknown
unknown, small
![Page 16: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/16.jpg)
55
![Page 17: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/17.jpg)
55
![Page 18: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/18.jpg)
55
![Page 19: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/19.jpg)
55
What About Pluto?
• Pluto does not easily fit into either category– Far from the sun (jovian)– Small (terrestrial)– Neither rocky nor gaseous (icy)– One moon– No rings
• It is similar in composition to some moons in the outer solar system and its orbit is similar to a group of objects called “Kuiper Belt Objects” or KBOs
![Page 20: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/20.jpg)
55
Charon• Largest of any moon in relation to the
planet it orbits (1/2 the size of Pluto)• Pluto and Charon are tidally locked to
each other (always show the same face)• Charon discovered in 1978 by
astronomers at the US Naval Observatory
![Page 21: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/21.jpg)
55
Concept Test
• Which of the following is NOT a reason why many astronomers think Pluto should not be classified as a planet. a. It is smaller than some moons.b. It has an orbit similar to many Kuiper Belt
Objects (KBO).c. Pluto is more similar in shape to irregular
asteroids and comets.d. Pluto is more similar in composition to
many moons and KBOs.e. Its orbit is far more elliptical and inclined
to the Sun relative to the other planets.
![Page 22: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/22.jpg)
55
KBOs
• Belt of icy objects outside Neptune’s orbit.
![Page 23: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/23.jpg)
55
Quaoar
• a = 43 AU• Orbit nearly
circular (e = 0.04)
• P = 285 years.
![Page 24: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/24.jpg)
55
Sedna
• a = 479 AU• Orbit (e = 0.84)• Aphelion = 76 AU• Perihelion = 884
AU– Currently = 90 AU
• P = 10,500 years
![Page 25: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/25.jpg)
55
Sedna
![Page 26: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/26.jpg)
55
“Xena”• 2003 UB313• A = 68 AU• E = 0.44• P = 560 years• Coming soon: mass
and density
![Page 27: 5 The Solar System A planet by any other name …](https://reader035.vdocuments.us/reader035/viewer/2022070410/56649f055503460f94c19da9/html5/thumbnails/27.jpg)
55
Homework #6Homework #6
• For Wednesday 20-Sept: Read article and answer questions in handout.