Mercury • Closest planet to the sun. • 2nd smallest planet • Mercury looks like our moon- many craters and cliffs.
Mercury Facts • Rev around the Sun-87 days • Rotation 58 days, 15 hours • Diameter- 4878 Kilometers, 3048 miles • No moons • No rings • Orbital Speed 47.89 km/s • .387AU from sun
Atmosphere of Mercury • Most gases on Mercury escaped, because of its low gravitational pull. • However, the gases that remain form a very thin atmosphere composed of: • hydrogen and helium, which we probably captured by Mercury from the sun’s solar winds • two others: sodium and potassium, which came up from the crust.
Temperature of Mercury • Because Mercury is so close to the sun and has hardly any atmosphere, its temperatures are extreme. • Surface temperature during the day reaches 450 C, 842 F and –170 C, -274 F at night.
Venus Second Planet from the Sun
Venus Facts • Revolution- 224.7 days • Rotation- 243 days • Diameter- 12,104 Km, or 7565miles • Orbital Speed- 35.03 km/s • No moons • No rings • .723 AU from sun
Earth’s Twin • Venus is called the Earth’s twin because it is very similar in mass and size. • The major difference is the atmosphere- Venus is covered by a thick, dense cloud of mostly carbon dioxide. This atmosphere is 90 times heavier than the Earth’s atmosphere which make the atmospheric pressure at sea level on Venus 90 times that of Earth’s.
Atmosphere • Since the atmosphere is mostly carbon dioxide, its atmosphere is highly toxic. This is because the carbon dioxide mixes with sulfur to create sulfur dioxide which is acid rain. This make the atmosphere appear yellow. • Clouds on Venus are so thick that they only let in 2% of the sunlight that strikes Venus top clouds to reach its surface. However, the atmosphere is so thick that all that heat is trapped which leads to the planet having the greenhouse effect.
Temperature on Venus • Temperatures on Venus normally remain around 470 C which is 878 F.
Explorers of Venus • In 1970 the first exploration on Venus occurred by the Russians. Their spacecraft called the Venera probe began to photo and mapped Venus’s surface
Magellan • The US followed by sending the Magellan in 1990 which mapped the surface of Venus with intense radar. This showed the surface to have huge craters, faults, volcanoes with visible lava.
Earth • The third planet from the sun is 150 million km away from the star. That is approximately 1 astronomical unit or AU. • Temperatures allow for solids, liquids, and gases on the Home Planet. • Most Meteors burn up in the atmosphere before reaching the surface.
Earth Facts • Diameter 12756 km or 7952 miles • Revolution 365.25 days • Rotation- 23 hours 56 minutes • Orbital speed- 29.79 km/s • 1 moon • No rings
Mars 4th Planet from the sun
The Red Planet • Revolution: 686.98 days • Rotation: 24 hours, 37 minutes • Diameter: 6794 km, or 4246.25 miles • Orbital Speed: 24 .13 km/s • 2 moons • No rings • 1.525 AU from sun
Why is it called the red planet? • Iron oxide in the weathered rocks on its surface give it’s a reddish appearance. • Mars also has polar ice caps that are visible from other and get larger during the Martian winter and shrink during the summer. Is it water? Yes and No- the southern polar ice cap is made of frozen carbon dioxide, the northern polar ice cap is made of water frozen into ice.
Mariner 9 • Orbited Mars in 1971-1972 • Revealed long channels that could have contained flowing water • Found largest volcano in the solar system, Olympus Mons
Viking 1 • 1976 landed on Mars with 2 probes, and 2 orbiters • The 2 orbiters Photographed the entire surface of Mars • The 2 probes landed and conducted experiments. Found No Evidence of LIFE.
Atmosphere of Mars • Much thinner than Earth’s • Composed of mostly carbon dioxide, some nitrogen, and argon. • This leads to temperature on the surface ranging from 35 C, 95 F to –170 C, -274 F. • There are also strong winds storms that can cover the entire planet at one time.
Moons of Mars • The moons of Mars are heavily cratered and very small • Phobos is 25 km in diameter. It’s orbit is expected to have it impact Mars in 50 million years. • Deimos is 13 km in diameter.
Phobos and Deimos • Named for the Greek war god Ares • Phobos means “fear” • Deimos means “panic”
Exploring Mars • In 2004 2 new probes landed on Mars. Spirit and Opportunity • Looked at rocks and found evidence of past water.
The Outer Planets 23.4
Jupiter • In 1979, Voyager 1 flew past Jupiter. • It is the 5th planet from the sun, and the largest planet in the solar system • Contains more mass than all the other planets combined. .
Facts about Jupiter • Diameter: 142, 796 km • Revolution: 11.86 years • Rotation: 9 hours, 55 minutes • 60+ moons • 1 ring ( faint dust rings) • 5.203 AU from sun
Atmosphere of Jupiter • The atmosphere is hydrogen and helium and gradually changes into a planet-wide ocean of liquid hydrogen and helium towards the middle of the planet. Jupiter may even have a solid rocky core. However, if it did it would not be like Earth’s because of extreme pressure(30 times Earth’s) and temperature. • The atmosphere appears full of colorful clouds- swirls of white,red, tan and brown.
Great Red Spot • In the atmosphere is also a continuous storm, that appears very red. It is full of swirling high pressure gases. This one storm is about 12000 km from top to bottom, and lightning has been observed in it the winds blow hundreds of kilometers an hour.
Rings and Moons • Jupiter has a faint dust ring around it. • Jupiter has 60+ moons,the four largest were discovered by Galileo in 1610. They are Io, Europa, Ganymede, Callisto.
Io • Closest to Jupiter • Gravity pulls on Io from Europa and Jupiter. This causes Io to be very hot. Io is the most volcanically active body in the entire solar system. • Io has no atmosphere- so you couldn’t hear or feel the volcanic blasts.
Europa 2nd moon out from Jupiter. Completely composed of rock with a thin crust of ice 70 miles deep. Under that ice is an ocean of water Has a thin oxygen atmosphere. It is also smooth- no impact craters, no valleys, no canyons, no mountains or volcanoes, no flood plains. Has right ingredients for primitive life.
Ganymede • Largest moon in the solar system- larger than Pluto and Mercury but not near the mass. • Consists mostly of ice- may have had oceans of water, but froze- if it were warmer, people could possibly live there. It’s daytime temp now is –180F
Callisto • 4th moon out from Jupiter • Composed of ice and rock • Has impact craters that are 4 billion years old, and its surface has stayed the same for almost that long. It is considered to be the longest intact surface in the solar system.
Saturn 6th Planet from the Sun