To say it is done using the transit of Venus isn't enough.\nwouldn't the distance from earth to Venus be needed?\nHow was that determined?
211881
The *relative* distances between the planets can be determined from Kepler's laws and Newtonian physics. This will give the ratios betwen all the distances in the solar system. Once this is done, only one *absolute* distance needs to be found to get all of the rest. Until fairly recently, absolute distances were determined through parallax. It is possible to watch a transit of Venus from two different locations on earth and get a parallax measurement of the distance to Venus in that way. This gives the actual distance between the earth and Venus, and so the distance from the earth to the sun.\n\nOther methods involved parallax measurements of asteroids that pass close enought to the earth to get good measurements. Now, it is much easier to use radio bounced off of other planets (or probes) and the speed of light to get the required absolute distances.
367243
Kepler suspected there should be a planet between Mars and Jupiter, but did nothing to search for one, and his laws are quite irrelevant to the issue, except for making it easier to determine how long a planet takes to orbit the Sun once its distance is known, or vice versa.  Newton never addressed this issue, but his laws help explain how planets move and to determine orbits more accurately.\nThe Titius relationship, following the discovery of Uranus, caused a group of German astronomers to organize a search for a planet between Mars and Jupiter, where Titius said one should exist.  The Germans were extremely methodical, creating a governing committee, a committee to draft by-laws, a committee to recruit more members, a committee to maintain contact with nonmembers, that a Sicilian found the desired object, Ceres, since he was studying the sky, not organizing committees.\nNeptune's existence was predicted, based on its gravitational effect on the orbit of Uranus, but neither Adams nor Leverrier, the two astronomers who determined the position of Neptune from those effects, made any use of Titius, just Newton.
463182
transporters will perform that function eventually throughout the solar system ! for work, dates, vacations, shopping, school, research, etc., our great grand children to the 5th power will consider it normal. and yes successful sub atomic transportation has already been sucessfully tested and is growing with leaps and bounds and will completely change our world as we know it !
131551
dude above this comment addressed some of the problems . . . but what about the solutions?\n\nFor my astrobiology class I did research on terraforming Mars, and learned quite a bit.  The first thing that would need to be done is landing, constructing miniature chemical fixing plants that could do to the atmosphere exactly what we're doing to this planet right now: release greenhouse gases that otherwise would be locked in the regolith. This would have to be done first to allow the planet to warm up a little bit, but this would take a few hundred years. You see, this would project would have to have the full commitment of the entire human race over a few thousand years for this to be "completed."\n\nAfter a few hundred years of warming,  you might actually outgas enough atmosphere from the regolith to hold liquid water stably, you might have a little more CO2 to build atmos. pressure, but growing algae or anything would require genetic engineering, since algae, im sure, is not going to grow in soils containing peroxides and epsom salts. They would fix the atmosphere to contain more oxygen. This would also take a few hundred years as well.\n\nAssuming we had the patience for this, we could have some sort of atmosphere close to 60% the pressure of ours within 600 years, and the temperatures from the 50s-70s (one scientific paper said something about 77F being reached feasibly). So this terraforming is do-able, but do we need to? have we finished discovering things on Mars before we start erasing it with running water and weather systems? \n\nSome say there is still a lot of water on Mars, enough to make an ocean covering the entire planet about a few feet deep (thats a lot), but that would take a lot of work to achieve.  Also, you have to realize that all this work would not be permanent.  Mars has no magnetic field, and thus no real protection from the solar wind which would slowly strip the planet of its atmosphere. \n\nthe "mars project" would be fruitful but not permanent, and would work for probably a good several millenia, but would need maintenance. . .  \n\nim done typing
106561
maybe you wanted to write 10th planet, not 11th planet.\n\nmaybe there was such a thing but i don't see any records of it on nasa-s site.\n\nWhat i do see is the report of the 10-th planet being discovered, maybe that's what u  were reffering to.\n\nhere's the link\n\nhttp://science.nasa.gov/headlines/y2005/29jul_planetx.htm
412867
time taken for the light to reach from the sun to earth\n                 =distance from the sun to earth/speed\n                 =93,000,000miles/186,000miles/second    \n                 =500 secs\n                 =500/60\n                 =8 1/3 secs.\n\n2.time takenfor the light to reach fromthe moon to earth\n                 =distance ofthe moon fromearth/speed of light\n                 =240,000 miles/186,000 miles/sec\n                 =1 9/31 sec\n\n3.400 square feet will be covered by 1 gallon of paint\n   4000 sft will be covered by (direct variation)=4000/400\n                                                                         =10 gallons\n   cost of painting=no of gallons times the rate per gallon\n                            =10gallons*$8.95/gallon\n                            =$89.50
8241
because some say  \nmen from mars women are from venus. \nso he didnt really want to go back to mars.
265791
The planets in our system are way, way too small to do anything like this. It would take something with the density of a black hole (or perhaps just a neutron star) to do something like this.
191144
It could be a planet or a satellite or some other celestial body. Venus is particularly bright.
431996
That work was much more time consuming and tedious for early explorers than it is for us today.  These sites should help you .... and here are some answers to your questions ...\n\n1.  In the third century B.C., the Greek astronomer and mathematician Eratosthenes estimated the Earth’s size by comparing the shadows cast at two locations at noon. He used his knowledge of triangles, circles, and angles to calculate the Earth’s circumference to within one percent of the actual measurement.\n\nThroughout history, mapmakers have been able to provide detailed maps of small areas, but it wasn't until the 17th century that mapmakers could make accurate measurements over larger areas. At that time, a new technique of measuring distance called triangulation revolutionized mapmaking. To determine the distance to a far-off point, mapmakers first measured the distance between two relatively close points and then measured the angle between each of these two points and the distant point using a transit or a theodolite. Once these angles and the distance between the two baseline points were known, the distance to the far-off point could be calculated using geometry. \n\nOne of the first official uses of triangulation for mapmaking was in 1669 when King Louis XIV of France commissioned Jean Picard and Jean Dominique Cassini to map the coast of France. This first accurate measurement of France showed it to be significantly smaller than earlier maps did. The King is said to have declared, "Your work has cost me a large part of my State!" \n\n2.  In the northern hemisphere, latitude may be derived by measuring the angle made between the North Star and the horizon. Crude instruments to obtain this angle have existed for thousands of years and instruments like the sextant and octant, only slightly less precise than those available to us, were in use.\n\nLatitude may also be calculated by measuring the altitude of the sun, moon, or certain planets and stars above the horizon on known days and reading latitude from tables designed for that purpose. It was not much more difficult for the captains and early explorers to measure these altitudes with a sextant or octant and to calculate latitude using one of the three ephemerae or astronomical almanacs they carried. These contained tables showing the daily position of celestial bodies such as the sun, the moon, and key stars. \n\n3.  Longitudinal observations were prone to error because chronometers did not have quartz batteries to keep them running.  When it ran down, it had to be re-calibrated using local time: using observation of the sun's zenith or local "noon" and then setting the chronometer by estimating the current longitudinal position. Over the course of a trip, the small incremental errors produced by this became larger ones.\n\nThere were other methods of calculating longitude available to early explorers, using astronomical observation. But many astronomical readings had to be acquired over the course of a night in order to obtain sufficiently precise data to determine longitude. It was asking a lot for men exhausted by the rigors of their daily work, to spend three or four hours at night taking sightings of the moon and stars, recording observations, and making calculations by candlelight or firelight. It was only natural that errors would exist in data obtained in this manner. Even the most skilled astronomer or surveyor would have been hard pressed to make highly accurate observations under such circumstances.
363070
The surface temperature on Venus is 800 degrees Fahrenheit.  As a point of comparison, paper catches fire at 451 degrees Fahrenheit.  The atmospheric pressure is immense.  The atmosphere is sulfur and methane and other poisons.  It's a hard sun-baked kiln oven landscape.   Not that you could ever see the sun, the atmosphere is too thick.  The night side is practically as hot as the day side because the superheated air covers the entire planet.   Sorry, I wish Venus was the lush tropical garden that they thought it was 100 years ago.  But a few unmanned probes have landed there and sent back pictures before they melted into a little puddle.  Looks just like the inside of an oven.
317018
THIS IS THE CRAZY ANSWER>>>>>>>>\n\nyes, there are vehicles that are not identifed.\n\nIf you mean other life forms then yes and no. It depends on what you mean by lifeform....\n\nThere is lifeforms on Mars and Venus and Earth is constantly vistited....\n\nHeres the crazy part....That these lives exist or rather are made up of a diffrent vibration than the physical plane... in other words its like Earth life is like an ice cube and Mars and Venus Life is like the Gas form of water.\n\nUFO exist and are made of thought energy...they are seen only when they want to be seen. They are constsantly visting earth helping allievate the amount of radiation we emmit...\n\nThey can not interfer with HUman free will which is why they do not present themselves...
147601
Well, really, we don't actually have a scientific definition of a planet.  Shocking yes.  Embarrassing even more so.  But we are working on it.  The problem we are facing right now is that we have a large collection of "transition objects" out there, things that sit right on the border of "planet or not."\n\nAt the high mass end, it is pretty clear cut, Things that produce internal energy by fusion are stars, things that don't are planets.  The transition between star and planet thus seems to be at about 12 times the mass of Jupiter.\n\nAt the small end things are muddled because of Pluto.  No good definition of planet exists that keeps only 9 planets.  You can make a definition to include Pluto, but then you must include a lot more objects.  This is where we actually focusing on right now.\n\n"gravitationally round" is thrown around a lot.  My professional opinion is that this one one make the cut.  It seems nice, a planet is a planet because it has enough self-gravity to crush itself into a round shape.  The problem with this definition is that it means we would have about 100 planets in out solar system.  The largest asteroid, Ceres is round, as are most of the icy bodies in the Kuiper Belt.\n\nThe one that seems to be picking up steam is "dynamically dominant."  This basically means that a planet "dominates" the space around them.  Take a look at the area around the earth - nothing else similar to it.  Same with Venus, Jupiter, and the rest. (moons and rings are bound to the planet so they don't count).  Ceres (the largest asteroid) is surrounded by many, many other asteroids.  Same goes for Pluto, it is surrounded by many other icy bodies of similar size (including one that is bigger than it).  This definition leaves us with 8 planets.\n\nReally right now the "planets" are just defined by fiat, they are planets because we call them that and nothing more.  As a planetary scientist I feel a little guilty not being able to actually define one of the words in the name of my field, as such I've honestly been spending far more time working on this whole "planet" mess, than on my own research.
80910
The sun is 93 million miles from Earth on the average, since the Earth does have a slightly elliptical orbit. How long it takes to get there is kind of an incomplete question because it all depends what you want to do when you get there.\n\nIt wouldn't take long for a spacecraft to fly straight to the sun and either fall into it or zoom by and then off into space, but if you wan to launch a probe to study the sun you have to be more clever.  \n\nThe link below is information on the Ulysses probe sent out in 1990. Ulysses actually did something of a "bank shot" off of Jupiter in order to get into an orbit where it goes around the sun over its poles rather than around the middle, which is rather cool that it worked so well.  Imagine playing billiards on a table three miles long and two wide and sinking the eight in a corner pocket after banking off of two cushions -- and then multiply that by a million, and you have a good idea how difficult this stuff is.
603773
Its just all a bit pointless.\n\nI mean, its cheaper to find the resources it has on Earth (shipping costs from the moon would be horrendous, even at bulk rate).\n\nIts a lousy holiday destination.\n\nAnd the weather is lousy - always close to absolute zero.\n\nSeriously, on Earth people colonised lands rich in life and almost always with existing human populations (which were duly displaced). Survival was trivial compared to the moon and the riches - in terms of new commodities to export - huge.\n\nWhy oh why oh why would you colonise a barren lump of ice cold lifeless rock?
383742
We do not have a real explanation...\nDuring the stage of formation of the solar system, the gases and dust accumulated to form one big blog, the sun, and several other blogs that became planets.  This cloud of dust was animated with a small rotation, and each blog rotated with slight differences.  The Sun formed, and the rest of the dust became planets, still with some remaining rotation.  At that time, many small blogs were floating around and hitting each other.  It is likely that, at that stage, Venus (or what would become Venus) was hit by another rock, changed rotation, and still running that way.\nSo, no, Venus is not "special".  It is just another rock that was formed at the time...
498123
We have the ability now to measure the orbit of the Earth, and all other planets, to very high precision, and it is not getting closer to the Sun.\n\nYou can do a very rough measurement yourself. If the Earth gets closer to the Sun, the Sun will appear bigger in the sky. Measure it in photographs taken by the same telescope a year apart. \n\nAnother consideration is this. Currently, the Moon and Sun appear the same size in the sky, which produces spectacular total eclipses of the Sun. If the Earth got just a little closer to the Sun, the Moon would no longer be able to completely cover the Sun. So if total solar eclipses continue as usual, that is evidence the Earth is not getting any nearer to the Sun.