Solar System Formation PDF

A DETAILED TOUR OF THE SOLAR SYSTEM HOW DID THE SOLAR SYSTEM FORM? The Nebular Hypothesis A. the nebula was composed mostly of hydrogen and helium B. about 5 billions years ago, the nebula began to contract C. it assumed a flat, disk shape with the protosun (pre-sun) at the center D. in...

A DETAILED TOUR OF THE SOLAR SYSTEM HOW DID THE SOLAR SYSTEM FORM? The Nebular Hypothesis A. the nebula was composed mostly of hydrogen and helium B. about 5 billions years ago, the nebula began to contract C. it assumed a flat, disk shape with the protosun (pre-sun) at the center D. inner planets begin to form from metallic and rocky clumps E. larger outer planets begin to form from fragments with a high percentage of ices The Story of Planet Building planets formed from the same protostellar material as the sun, still found in the sun’s atmosphere. ○ mass of less than ~ 15 earth masses ○ planets can not grow by gravitational collapse ○ earthlike planets rocky planet material formed from clumping together of dust grains in the protostellar cloud. ○ mass of more than ~ 15 earth masses ○ planets can grow by gravitationally attracting material from the protostellar cloud ○ jovian planets (gas giants) Formation and Growth of Planetesimals planet formation starts with clumping together of grains of solid matter: planetesimals planetesimals collide to form planets planetesimal growth through condensation and accretion. gravitational instabilities may have helped in the growth of planetesimals and protoplanets. The Growth of Protoplanets simplest form of planet growth: unchanged composition of accreted matter over time ○ as rocks melted, heavier elements sink to the center -> differentiation ○ also produces a secondary atmosphere -> outgassing improvement of this scenario: gradual change of grain composition due to cooling of nebula and storing of heat from potential energy WHY SOLAR SYSTEM? “sol” is the latin name of the sun solar system means “system of the sun” star system is constituted by the: ○ sun ○ 8 planets: mercury, venus, earth, mars, jupiter, saturn, uranus, and neptune. ○ 5 dwarf planets: pluto, eris, haumea, makemake, ceres ○ planetary debris: asteroids, meteoroids, comets The Sun (heart of solar system) a star, a hot ball of glowing gasses solar nebula: sun formed about 4.6 billion years ago in a giant, spinning cloud of gas and dust ○ mean radius: 109.2 x that of earth’s ○ volume: 1,301,018.805 earths ○ mass: 333,060.402 x earth's ○ maximum surface temp: 5,500 °c solar interior ○ core: sun's central region; produce energy ○ radiative zone: energy from the core moves outward in the form of radiation ○ convection zone: creating convection currents that carry energy to the surface photosphere (sunspots): visible surface of the sun chromosphere: thin layer above the photosphere corona: outermost layer of the sun's atmosphere The Planets the word “planet” means wanderer IAU International Astronomy Union (2006) defines planet as any celestial body that: ○ a. in orbit around the sun ○ b. sufficient mass for itself-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium ○ c. has cleared the neighborhood around its orbit terrestrial: four innermost planets meaning earth like - mercury, venus, earth, and mars, gas giants or jovian planets: four larger outer planet - jupiter, saturn, uranus and neptune: composed of gasses such as hydrogen and helium 1  criterion which demoted pluto THE PLANETS IN ORBIT Terrestrial (Inner) Planets 1. Mercury derived roman god mercury smallest planet - only slightly larger than earth's moon 2nd densest planet fastest revolving planet - 88 days very little atmosphere, extreme temperature variation:too extreme for organisms to adapt to has no moons, no rings 2. Venus roman goddess of love and beauty, aphrodite hottest planet, world of intense heat and volcanic activity thick and toxic atmosphere traps heat in a runaway "greenhouse effect” veiled planet: because its thick atmosphere earth’s twin sister - similar in structure and size spins slowly in the opposite direction of most planets has no moons, no rings unlikely place for life as we know it, but some scientists theorize microbes might exist 3. Earth presence of water and life: tide, seasons, eclipse an old english word: ground: eor(th)e and ertha oceans, atmosphere and lithosphere moon: luna how did the moon form? ○ great impact theory: moon formed from debris after a massive collision between earth and a mars-sized body. this theory suggests that about 4.5 billion years ago, a mars-sized object collided with earth. the impact caused a huge amount of debris to be ejected into space. over time, this debris gathered together due to gravity, forming the moon. this explains why the moon is composed of materials similar to earth's outer layers. 5. Mars roman god of war, mars red planet, dry, rocky, and bitter cold reddish is due to oxidization – or rusting – of iron in the rocks seasons, polar ice caps, volcanoes, canyons and weather next earth, thin atmosphere made up mostly of carbon dioxide, nitrogen, and argon gasses scientists don't expect to find living things currently thriving on mars; instead, they're looking for signs of life that existed long ago moons: phobos, deimos (potato-shaped because they have too little mass) Jovian (Outer) Planets 6. Jupiter king of roman ancient roman gods, jupiter biggest planet strongest surface gravity fastest rotation an ocean made of hydrogen instead of water extreme pressures and temperatures deep inside the planet crush, melt, and vaporize great red spot: gigantic storm that’s about twice the size of earth and has raged for over a century little red spot: giant storms in southern hemisphere powered by warm air rising in their centers moons: more than 75 moons 4 largest moons: io, europa, ganymede, and callisto 7. Saturn roman god of agriculture and wealth, saturn elegant planet—thousand beautiful ringlets made of chunks of ice and rocks density less than that of water made of billions of individual particles of mostly water ice which create waves spread over hundreds of thousands of km, yet they are extremely thin – perhaps only 10 m thick. cassini division: big gap between 2 of saturn's main rings, called the a ring and the b ring. ring: 7 rings and several gaps and divisions between them ( d, c, b, a, f, g and e) moons: titan, enceladus, lapetus, mimas (53 moons with an additional 29 moons awaiting confirmation) 2 8. Uranus greek god of sky, uranus topsy-turvy planet-- equator is nearly at right angles to its orbit very cold and windy planet, ice giant blue-green in color due to large amounts of methane, which absorbs red light but allows blues to be reflected twin in size to neptune sunlight passes through the atmosphere and is reflected back out by uranus' cloud rings: 13 known rings - inner rings, narrow and dark; outer rings, brightly colored moon: miranda (28 known moons) 9. Neptune roman god of sea, neptune most of its mass is a hot, dense fluid of "icy" materials atmosphere is made up mostly of molecular hydrogen, atomic helium and methane great dark spot, solar system's windiest world longest revolution period (165 years)-- completed its first orbit in 2011 since its discovery in 1846 rings: 5 main rings, galle, leverrier, lassell, arago, and adams. moon:16, largest moon (triton) planets radius mass escape rotational revolution surface surface moons velocity period period temp gravity mercury 2438 km 3.3x1023 kg 4.3km/s 59 days 88 earth days 400k 0.38 g 0 venus 6052 km 4.87x1024 kg 10 km/s 243 days 225 earth days 730k 0.91 g 0 earth 6378 km 5.974x1024 kg 11km/s 1 day 365.25 earth days 280k 1.0 g 1 mars 3397 km 6.42x 1023 kg 5.0 km/s 24.6 hours 687 earth days 210k 0.38 g 2 jupiter 71492 km 1.90x1027 kg 60 km/s 9.9 hours 11.8 earth years 125k 2.54 g 50+ saturn 60268 km 5.69x1026 kg 39 km/s 10.7 hours 29.5 earth years 25k 1.08 g 30 uranus 25 559 8.69x1025 kg 21km/s 17.2 hours 84 earth years 60k 0.91 g 21 km neptune 24 764 1.02x1026 kg 23 km/s 16.1 hours 165 earth years 60k 1.19 g 8 km Dwarf Planets in 2006, pluto, eris and the asteroid ceres became the first dwarf planets. lack the gravitational muscle to sweep up or scatter objects near their orbits and end up orbiting the sun in zones of similar objects such as the asteroid and kuiper belts. 3  other dwarf planets: makemake, haumea 1. Pluto reclassified as a dwarf planet in 2006 mountains, valleys, plains, craters, and glaciers thin, tenuous atmosphere rocky core surrounded by a mantle of water ice moons: 5, charon, nix, hydra, kerberos, and styx kuiper belt: member of a group of objects that orbit in a disc-like zone beyond the orbit of neptune 2. Ceres "embryonic planet," which means it started to form but didn't quite finish largest object in the asteroid belt between mars and jupiter countless small, young craters thin atmosphere, contains water vapor takes 1,682 earth days 3. Makemake donut-shaped region of icy bodies 305 earth years frozen methane and ethane on its surface 4. Haumea oval-shaped, fastest rotating large objects 285 earth years made of rock with a coating of ice. moons: namaka and hi”iaka rings: first known kuiper belt object to have rings 5. Eris largest dwarf planet 557 earth years moon: dysmonia rocky surface similar to pluto Planetary Debris Asteroid rocky, airless worlds that orbit our sun, but are too small to be called planets. size ranges from 1 km to 900 km classified as either carbonaceous (c), silicaceous (s) or metallic (m) region called the asteroid belt or simply the main belt, may contain millions of asteroids. asteroids that pass close to earth are called near earth objects (neos). Comet short period (