what is the diameter of the solar system?
492540
It all depends where you draw the line.\n\nThe planet Pluto has the most eccentric orbit of all of the planets, but Pluto's orbit takes it to 49.5 Astronomical Units, 7.4 billion kilometers, at the farthest point from the Sun. \n\nThe Oort cloud is an immense spherical cloud surrounding the planetary system and extending approximately 3 light years, about 30 trillion kilometers from the Sun. This vast distance is considered the edge of the Sun's orb of physical, gravitational, or dynamical influence.
619435
Hi ... The diameter of Mars is 4228.4 Miles ... follow the link below for loads more info ... Hope this helps !!!
587636
If you mean the diameter of the horizon, it's a function of how high you are above the surface.  If you're ON the surface, the diameter is zero.  If you're a distance h above the surface and the radius of the earth is r, the diameter is\n\nd=2*(2rh + h^2)^.5
642481
If we confine ourselves to only the surfaces of planets and minor bodies, the answer is virtually all of the surface area in our solar system has been mapped at least at some resolution. The Planetary Cartography Working Group has identified over 1.9 billion square kilometers of stable surfaces in the solar system, not including the atmospheric features of Jupiter, Saturn, Uranus and Neptune, and of this total, all but a few percent have been mapped at resolutions of 10 - 100 meters or lower. Some surfaces such as the Moon and the Earth, have been mapped at substantially higher resolution.\n\nThis means that there are very few surprises left for us to 'see for the first time' in this solar system. Now comes the hard job of geophysically and minerologically assaying these surfaces to determine their chemical composition and how they got to be the way they are!
150417
The apparent diameter of a celestial object is the diameter measured by an observer at a specific distance from the object. The smaller the distance between the observer and object, the greater the apparent diameter. Apparent diameters are often expressed as angular diameters.
174111
Diameter is 8\nRadius is 8/2, or 4\n\nCircumference is 2 * pi * r = 2 * pi * 4\n\nANSWER : 8 pi\n\nEDIT : No, I'm pretty sure I'm right. I googled and found this (http://mathforum.org/library/drmath/view/57735.html) : "The circumference of a circle is pi times the diameter, so the diameter can be found by circumference/pi = diameter."\n\nSince the diameter is 8, the circumference is 8 pi.\n\nEDIT : Thanks, Mike! :)
41352
Well, the diameter of the planet is 12,756.3 km.  That would make the radius approximately 6,378 km.  So the radius shoud be an approximation of the distance between the inner core and the surface.\n\nAh ha!  I just look it up and I was right! "Inner core (5000 km - 6370 km below the Earth's surface)."\n:o)
349558
Here's a whole lot about the planet closest to the Sun in the Solar System:
751259
Earth is roughly 8,000 miles in diameter, and 25,000 miles in circumference.
147445
Its all relative..usually we use sun as a point of a reference when we talk about relative size of planets which circle it. Pluto is about the same size as mercury.
541450
The diameter of the Earth's orbit around the Sun is about 300,000,000 kilometers
667527
Nice links. I would think that Pluto is still a planet. Its mean radius relative to earth's radius is approximately 0.46. So the diameter at equator might be some 3600 miles. By comparison, a satellite like Nereid, which orbits the planet Neptune, is no more than 200 miles in diameter. At its size Pluto must be a planet.\nI am not sure about Sedna. If we think about the 10-th planet, or the "X" planet, it was thought to be three times as massive as Saturn, and nearly six billion miles from the earth. It looks to me that Sedna might not be our 10-th planet. But then again, perhaps we just have to wait and see.
166452
solar system I guess? 312.500.000 km, but there is no planet at such distance...what is it?\n\nasteroid belt...\n\n6  1/4=6.25\n6.25 x 200,000,000 / 4 = 312,500,000
1183745
Mars is much smaller than Earth.  About 1/2 the diameter (0.53), and 1/10 of the mass (0.107) of the Earth.\n\nHere's a great set of illustrations showing the relative sizes of all the planets, and the sun.\n\nhttp://www.comagz.com/webmagazine/story/proportions_how_small_we_are
425199
i suspect that the solar system is located in a spur of the sagittarius arm.\n\nhttp://en.wikipedia.org/wiki/Sagittarius_Arm
606341
It depends on whether you are talking about a planet in our solar system or an extra solar planet. I'll describe both.\n\nFor a planet in our solar system, the apparent size can be directly measured optically. One way is to take a picture of the planet through the telescope and measure the size of the picture with a ruler. Calculations based on the focal length of the telescope will tell you how many degrees (or fractions of a degree, since it will be less than 1) wide the planet appears to be in the sky for a given measured size on the photograph. Then the distance to the planet must be measured, which is not so easy. Basically it comes from triangulation to nearby asteroids combined with kepler's laws. Knowing the distance and apparent size allows you to calculate the real size and volume. To get the density, you need to know the mass. If the planet has Moons, the orbital period of the moons gives you the planet's mass from orbital mechanics calculations. If the planet has no moon, like Mercury and Venus, then theoretically their mass can be gotten from the effect their gravity has on the orbits of other planets, asteroids and comets, but this is not so accurate since those other objects don't usually pass close enough to the planet we want to measure to show much of an effect on their orbits. Fortunately we have sent space craft to Mercury and Venus and measured their mass directly by the effect their gravity had on the space craft's path.\n\nFor a planet orbiting another star, it is not so easy, because such planets cannot even be seen. Their presence is deduced from tiny Doppler shifts of the star they orbit. A planet does not just orbit a star, the star and planet orbit each other around their common center of gravity. Since the star is much heavier than the planet, it doesn't move much, but it does move, and modern instruments can measure the tiny Doppler shift in the star's light to get the motion of the star. Stellar evolution models tell us how heavy the star is and orbital mechanics tell us how heavy the planet is. (We can calculate the mass of double stars using orbital mechanics and the Doppler shift of each star's light, but we have no direct knowledge of the mass of single stars.) If the planet also happens to orbit in a plane parallel to our line of site, it will cross directly in front of the star once each orbit, like Venus sometimes crosses the face of our sun as seen from Earth. When it does, it blocks a small percentage of the star's light and the star looks slightly dimmer. If the star dims by 1%, then the disk of the planet has 1% the area of the disk of the star. Again, from stellar evolution models, we can deduce the diameter of the star and so get the diameter of the planet. (We can measure the diameter of some large, nearby stars, directly with the largest telescopes and adaptive optics, but for most stars we have no direct knowledge of their diameter.)\n\nThere is much more detail, but enough is enough, don't you think?
823309
If you write the number sequence 0,3, 6, 12, 24, 48, 96, and add 4 to each number (4, 7, 10, etc) then divide by ten, you get the distance of each planet from the Sun, measured in astronomical units (1 a.u.=93 million miles=150 million kilometers).  This works out as Mercury 0.4, Venus 0.7, Earth 1.0, Mars 1.6, --- 2.8, Jupiter 5.2, and Saturn 10.0  This works out pretty accurately, but there was nothing at 2.8. Herschel discovered Uranus in 1781 at 19.6, right where another planet was supposed to go according to the Titius rule.   When Ceres was discovered in 1801, it was at 2.72, filling the gap.  Neptune, however is not near 38.8, but at 30.  Astronomers now believe the "law" is either a coincidence, or the result of billions of years of gravitational interactions.