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how many planets, their names in order,their distance from the sun,etc,.

2007-09-07 20:13:09 · 6 answers · asked by hari 1 in Science & Mathematics Astronomy & Space

6 answers

The Sun is the Solar System's parent star, and far and away its chief component. Its large mass gives it an interior density high enough to sustain nuclear fusion, which releases enormous amounts of energy, mostly radiated into space as electromagnetic radiation such as visible light.

The Sun is classified as a moderately large yellow dwarf, but this name is misleading as, compared to stars in our galaxy, the Sun is rather large and bright. Stars are classified by the Hertzsprung-Russell diagram, a graph which plots the brightness of stars against their surface temperatures. Generally, hotter stars are brighter. Stars following this pattern are said to be on the main sequence; the Sun lies right in the middle of it. However, stars brighter and hotter than the Sun are rare, while stars dimmer and cooler are common.[23]


The Hertzsprung-Russell diagram; the main sequence is from bottom right to top left.It is believed that the Sun's position on the main sequence puts it in the "prime of life" for a star, in that it has not yet exhausted its store of hydrogen for nuclear fusion. The Sun is growing brighter; early in its history it was 75 percent as bright as it is today.[24]

Calculations of the ratios of hydrogen and helium within the Sun suggest it is halfway through its life cycle. It will eventually move off the main sequence and become larger, brighter, cooler and redder, becoming a red giant in about five billion years.[25] At that point its luminosity will be several thousand times its present value.

The Sun is a population I star; it was born in the later stages of the universe's evolution. It contains more elements heavier than hydrogen and helium ("metals" in astronomical parlance) than older population II stars.[26] Elements heavier than hydrogen and helium were formed in the cores of ancient and exploding stars, so the first generation of stars had to die before the universe could be enriched with these atoms. The oldest stars contain few metals, while stars born later have more. This high metallicity is thought to have been crucial to the Sun's developing a planetary system, because planets form from accretion of metals

Inner planets
The inner planets. From left to right: Mercury, Venus, Earth, and Mars (sizes to scale)The four inner or terrestrial planets have dense, rocky compositions, few or no moons, and no ring systems. They are composed largely of minerals with high melting points, such as the silicates which form their solid crusts and semi-liquid mantles, and metals such as iron and nickel, which form their cores. Three of the four inner planets (Venus, Earth and Mars) have substantial atmospheres; all have impact craters and tectonic surface features such as rift valleys and volcanoes. The term inner planet should not be confused with inferior planet, which designates those planets which are closer to the Sun than Earth is (i.e. Mercury and Venus).

Mercury
Mercury (0.4 AU) is the closest planet to the Sun and the smallest planet (0.055 Earth masses). Mercury has no natural satellites, and its only known geological features besides impact craters are "wrinkle-ridges", probably produced by a period of contraction early in its history.[36] Mercury's almost negligible atmosphere consists of atoms blasted off its surface by the solar wind.[37] Its relatively large iron core and thin mantle have not yet been adequately explained. Hypotheses include that its outer layers were stripped off by a giant impact, and that it was prevented from fully accreting by the young Sun's energy.

Venus
Venus (0.7 AU) is close in size to Earth (0.815 Earth masses) and, like Earth, has a thick silicate mantle around an iron core, a substantial atmosphere and evidence of internal geological activity. However, it is much drier than Earth and its atmosphere is ninety times as dense. Venus has no natural satellites. It is the hottest planet, with surface temperatures over 400 °C, most likely due to the amount of greenhouse gases in the atmosphere. No definitive evidence of current geological activity has been detected on Venus, but it has no magnetic field that would prevent depletion of its substantial atmosphere, which suggests that its atmosphere is regularly replenished by volcanic eruptions.

Earth
Earth (1 AU) is the largest and densest of the inner planets, the only one known to have current geological activity, and the only planet known to have life. Its liquid hydrosphere is unique among the terrestrial planets, and it is also the only planet where plate tectonics has been observed. Earth's atmosphere is radically different from those of the other planets, having been altered by the presence of life to contain 21% free oxygen. It has one satellite, the Moon, the only large satellite of a terrestrial planet in the Solar System.

Mars
Mars (1.5 AU) is smaller than Earth and Venus (0.107 Earth masses). It possesses a tenuous atmosphere of mostly carbon dioxide. Its surface, peppered with vast volcanoes such as Olympus Mons and rift valleys such as Valles Marineris, shows geological activity that may have persisted until very recently. Mars has two tiny natural satellites (Deimos and Phobos) thought to be captured asteroids.

Asteroid belt
Image of the main asteroid belt and the Trojan asteroidsAsteroids are mostly small Solar System bodies composed mainly of rocky and metallic non-volatile minerals.

The main asteroid belt occupies the orbit between Mars and Jupiter, between 2.3 and 3.3 AU from the Sun. It is thought to be remnants from the Solar System's formation that failed to coalesce because of the gravitational interference of Jupiter.

Asteroids range in size from hundreds of kilometres across to microscopic. All asteroids save the largest, Ceres, are classified as small Solar System bodies, but some asteroids such as Vesta and Hygieia may be reclassed as dwarf planets if they are shown to have achieved hydrostatic equilibrium.

The asteroid belt contains tens of thousands, possibly millions, of objects over one kilometre in diameter.[45] Despite this, the total mass of the main belt is unlikely to be more than a thousandth of that of the Earth. The main belt is very sparsely populated; spacecraft routinely pass through without incident. Asteroids with diameters between 10 and 10-4 m are called meteoroids.


Ceres
Ceres (2.77 AU) is the largest body in the asteroid belt and its only dwarf planet. It has a diameter of slightly under 1000 km, large enough for its own gravity to pull it into a spherical shape. Ceres was considered a planet when it was discovered in the 19th century, but was reclassified as an asteroid in the 1850s as further observation revealed additional asteroids.[48] It was again reclassified in 2006 as a dwarf planet.

Asteroid groups
Asteroids in the main belt are divided into asteroid groups and families based on their orbital characteristics. Asteroid moons are asteroids that orbit larger asteroids. They are not as clearly distinguished as planetary moons, sometimes being almost as large as their partners. The asteroid belt also contains main-belt comets[49] which may have been the source of Earth's water.
Trojan asteroids are located in either of Jupiter's L4 or L5 points (gravitationally stable regions leading and trailing a planet in its orbit); the term "Trojan" is also used for small bodies in any other planetary or satellite Lagrange point. Hilda asteroids are in a 2:3 resonance with Jupiter; that is, they go around the Sun three times for every two Jupiter orbits.

The inner Solar System is also dusted with rogue asteroids, many of which cross the orbits of the inner planets.


Outer planets
Jupiter
Jupiter (5.2 AU), at 318 Earth masses, masses 2.5 times all the other planets put together. It is composed largely of hydrogen and helium. Jupiter's strong internal heat creates a number of semi-permanent features in its atmosphere, such as cloud bands and the Great Red Spot. Jupiter has sixty-three known satellites. The four largest, Ganymede, Callisto, Io, and Europa, show similarities to the terrestrial planets, such as volcanism and internal heating. Ganymede, the largest satellite in the Solar System, is larger than Mercury.

Saturn
Saturn (9.5 AU), famous for its extensive ring system, has similarities to Jupiter, such as its atmospheric composition. Saturn is far less massive, being only 95 Earth masses. Saturn has sixty known satellites (and 3 unconfirmed); two of which, Titan and Enceladus, show signs of geological activity, though they are largely made of ice. Titan is larger than Mercury and the only satellite in the Solar System with a substantial atmosphere.

Uranus
Uranus (19.6 AU), at 14 Earth masses, is the lightest of the outer planets. Uniquely among the planets, it orbits the Sun on its side; its axial tilt is over ninety degrees to the ecliptic. It has a much colder core than the other gas giants, and radiates very little heat into space. Uranus has twenty-seven known satellites, the largest ones being Titania, Oberon, Umbriel, Ariel and Miranda.

Neptune
Neptune (30 AU), though slightly smaller than Uranus, is more massive (equivalent to 17 Earths) and therefore denser. It radiates more internal heat, but not as much as Jupiter or Saturn.[54] Neptune has thirteen known satellites. The largest, Triton, is geologically active, with geysers of liquid nitrogen.[55] Triton is the only large satellite with a retrograde orbit. Neptune is accompanied in its orbit by a number of minor planets in a 1:1 resonance with it, termed Neptune Trojans

2007-09-08 02:32:26 · answer #1 · answered by ђermiona 6 · 0 0

The Solar System or solar system[a] consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 165 known moons,[1] three dwarf planets (Ceres, Pluto, and Eris and their four known moons), and billions of small bodies. This last category includes asteroids, Kuiper belt objects, comets, meteoroids, and interplanetary dust.

In broad terms, the charted regions of the Solar System consist of the Sun, four terrestrial inner planets, an asteroid belt composed of small rocky bodies, four gas giant outer planets, and a second belt, called the Kuiper belt, composed of icy objects. Beyond the Kuiper belt lies the scattered disc, the heliopause, and ultimately the hypothetical Oort cloud.

In order of their distances from the Sun, the planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Six of the eight planets are in turn orbited by natural satellites, usually termed "moons" after Earth's Moon, and each of the outer planets is encircled by planetary rings of dust and other particles. All the planets except Earth are named after gods and goddesses from Greco-Roman mythology. The three dwarf planets are Pluto, the largest known Kuiper belt object; Ceres, the largest object in the asteroid belt; and Eris, which lies in the scattered disc.

2007-09-07 20:31:30 · answer #2 · answered by ANKIT S 4 · 0 0

Build Solar Power Easily : http://SolarPower.duebq.com/?Nkt

2017-04-04 05:35:25 · answer #3 · answered by ? 3 · 0 0

Can't you figure out how to work a search engine?

www.kidsastronomy.com/solar_system.htm
solarsystem.nasa.gov/

etc. etc.

Doug

Edit:
Pssstttt.......... Julius. You got Mars and the asteroid belt backwards ☺

2007-09-07 20:20:49 · answer #4 · answered by doug_donaghue 7 · 0 0

What?!....well..........okay, SUN the center...the, MERCURY, VENUS, EARTH,ASTERIODS, MARS JUPITER, SATURN, URANUS, NEPTUNE, PLUTO AND GLEISE581C....You get it?

2007-09-07 20:18:57 · answer #5 · answered by Anonymous · 0 0

Look it up on line. Is this your homework?

2007-09-07 20:23:20 · answer #6 · answered by Barbra 6 · 0 0

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