Mercury ,Venus and Earth

By Area 6’s red faction team: Kallem ,Ryan, Reece, Richard, Yi seng, Avinash, Jackie, jade

2011

Guide to the solar system

Our solar system

• From our small world we have gazed upon the cosmic ocean for thousands of years. Ancient astronomers observed points of light that appeared to move among the stars.

• They called these objects planets, meaning wanderers, and named them after Roman deities --Jupiter, king of the gods Mar’s, the god of war; Mercury, messenger of the gods;Venus, the goddess of love and beauty; and Saturn, father of Jupiter and god of agriculture.

• The stargazers also observed comets with sparkling tails, and meteors -- or shooting stars apparently falling from the sky.

• Since the invention of the telescope, three more planets have been discovered in our solar system: Uranus(1781), Neptune(1846) and Pluto(1930). Pluto was reclassified as a dwarf planet in 2006. In addition, our solar system is populated by thousands of small bodies such as asteroids and comets. Most of the asteroids orbit in a region between the orbits of Mars and Jupiter, while the home of comets lies far beyond the orbit of Pluto, in the Oort Cloud.

• The four planets closest to the sun -- Mercury, Venus, earth, and Mars -- are called the terrestrial planets because they have solid rocky surfaces. The four large planets beyond the orbit of Mars -- Jupiter, Saturn, Uranus, and Neptune -- are called the gas giants.

• Beyond Neptune, on the edge of the Kuiper belt, tiny, distant, dwarf planet Pluto has a solid but icier surface than the terrestrial planets.

Mercury• Sun-scorched Mercury is only slightly larger than Earth’s Moon. Like the Moon, Mercury has

very little atmosphere to stop impacts, and it is covered with craters. Mercury's dayside is super-heated by the sun, but at night temperatures drop hundreds of degrees below freezing. Ice may even exist in craters. Mercury's egg-shaped orbit takes it around the sun every 88 days

• Mercury is named after the roman god Hermies because it is moving at 30 miles[48 km] a second.

• Mercury is the innermost and smallest planet in the Solar System,[a]orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits.

• The perihelion of Mercury's orbit precesses around the Sun at an excess of 43 arcseconds per century; a phenomenon that was explained in the 20th century by Albert Einstein's General Theory of Relativity.

• Mercury is bright when viewed from Earth, ranging from −2.3 to 5.7 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun is only 28.3°. Since Mercury is normally lost in the glare of the Sun, unless there is a solar eclipse it can be viewed from Earth's Northern Hemisphere only in morning or evening twilight, while its extreme elongations occur in Declinations south of the celestial equator, such that it can be seen at favorable apparitions from moderate latitudes in the Southern Hemisphere in a fully dark sky.

Venus

• Venus is the second planet from the Sun and the sixth largest. Venus' orbit is the most nearly circular of that of any planet, with an eccentricity of less than 1%.

• Orbit: 108,200,000 km (0.72 AU) from Sun • Diameter: 12,103.6 km • Mass: 4.869e24 kg

• Venus is a dim world of intense heat and volcanic activity. Similar in structure and size to Earth, Venus' thick, toxic atmosphere traps heat in a runaway "greenhouse effect." The scorched world has temperatures hot enough to melt lead. Glimpses below the clouds reveal volcanoes and deformed mountains. Venus spins slowly in the opposite direction of most planets

• Earth is an ocean planet. Our home world's abundance of water -- and life -- makes it unique in our solar system. Other planets, plus a few moons, have ice, atmospheres, seasons and even weather, but only on Earth does the whole complicated mix come together in a way that encourages life -- and lots of it.

• Metric • Orbit Size (semi-major axis): 149,598,262 km • Mean Radius: 6,371.00 km • Volume: 1,083,206,916,846 km3 • Mass: 5,972,190,000,000,000,000,000,

000 kg

Earth

Bibliography

• Info from• National Aeronautics and space administration• How the universe works• 100 facts about space• Mercury and Venus• The Usborne complete book of Astronomy and space