It takes 8 minutes for the suns light to reach earth, if the sun were to "turn off" how long before the earth
399043
a couple good hours. heck, if that ever were to happen, I'd move to Cancun!
418592
We can see backwards in time by looking into the night sky. Light from stars and galaxies takes a physical amount of time to get to us. When we look at the Sun we can only see it as it was 8 minutes ago 'cos that's how long it takes for light from the Sun to reach the Earth. It takes 4.3 years from the nearest star, so we see it as it was 4.3 years ago. It takes 2.5 million years from the nearest galaxy in Andromeda, so we see it as it was 2.5 million years ago. The furthest objects are around 15 billion light years away so when we are observing them we are looking backwards in time 15 billion years this is 10 billion years before the Earth and Sun even existed! We are close to witnessing creation itself. Light travels at 186,262 miles per second in a vacuum or 7 times around the world in a second. Jules.
301591
OK, first lets say that the rocket moves at a constant speed of 80% of the speed of light. Working with an accelerating rocket would be hard and .8 is a convienent number.\n\nso we have beta=.8 \ngamma=1/sqrt(1-.8^2)=5/3 and \nbeta*gamma= 4/3\n\nIf you dont understand this, look up lorentz transform in your textbook.\n\nWe will use a two dimensional unprimed coordinate system with distance in light minutes on the x axis and time in minutes on the y axis. The sun is located at x=0 and the earth at x=8 light minutes. Draw 45 degree lines, representing light rays, intersecting the x=0 axis at one minute intervals. Draw a vertical line at x=8 representing the earth. The light ray starting at (0,-8) intersects the earth at (8,0) meaning this is the event where people on earth observe what happened on the sun 8 minutes ago. We will call this event A.\n\nDraw a line with a slope -1/.8 intersecting A. This is the path of the spaceship. It will reach the sun at the time 10 minutes.\n\nNow we will calculate the cooridinates of event A as seen by the spaceship approaching the sun. We have\n\nA'= [gamma       beta*gamma]  [8]\n.......[beta*gamma  gamma     ]  [0]\n\nA'= 1/3 [5 4] [8] =  [13.3]\n.............[4 5] [0]  ... [10.6]\n\n(hopefully the ... makes the matricies line up)\nSo the guy in the spaceship NAMES this point 13.3 light minutes and 10.6 minutes.\n\n\nNow lets look at where the line of the light ray from (0,0) intersects the path of the spaceship. Using trig we get (4.44,4.44). Call this point B. This is where the guy in the spaceship observes what happened on the sun at time 0.\n\nNow lets lorentz transform this point\nB'= 1/3 [5 4] [4.44]  = [13.3]\n.............[4 5] [4.44] ...   [13.3]\n\nnotice that the x' coordinate is 13.3 for both point A' and B'. This is because from the perspective of the guy in the ship, he has not moved. The elapsed time for the guy in the ship between A' and B' is 13.3-10.6 = 2.7 minutes.\n\nSo, he has seen 8 minutes worth of dancing in just 2.7 minutes. The image has speeded up.\n  \n* This is the correct method for solving this problem, but you might want to double check my math.
334395
Light is cool stuff.It acts like radiation but when it hits something it act like a particle.You cant see light until it hits something and it releases its energy.So most of the light after you turn the switch off hits something and ceases to be but a very small amount might be lucky to shine out to open sky and even less might leave earth.It will keep going till it hits something all happening at the speed of light.Like looking at very distant stars ,its taken billions of years for the light to reach us.The star is long gone switched off but we are still seeing the light from it very diffused but what we see hasn't hit anything on its journey and it's an infinitely small amount of what originally left that star/sun
954912
It averages between 91 and 94 million miles. You can check this by multiplying the speed of light (186,000 miles per second) by the time it takes light to reach the Earth (8 min, 16 sec.)\n\n30 NOV 06, 1711 hrs, GMT.
1178302
Mean distance from earth149.6×10^6 km or (92.95×10^6 mi)\nIt would take about 8.31 minutes at the speed of light to go from earth to sun.
317324
If you are asking about Aliens, then I would say that I doubt that any have visited.  The nearest star is about 4 light years away.  Meaning that traveling 186,000 miles a second it takes light 4 years from the nearest star to reach earth.  The light from the sun arrives in something like 9 minutes.  If an alien were to visit, it would be a large undertaking, and the would probably make a grand entrance and visit with Earth's dignitaries.
1066033
Somewhere around 10 million years. This should be compared to the sun, which will last a total of 10 *billion* years.\n\nHomework?
1040094
I remember it being said that if you were to travel at light speed for an hour, the amount of time that would pass on Earth would equate to years.  Indeed, it went further on to say that a baby would have grown into an old person in the amount of time that elapsed.  Taking that into account (let's say 60 years), assuming that the passage of time would be linear, and that there are 8,760 hours in one year, then perhaps some 525,600 years would've passed on Earth.  \n\nHowever, I'm thinking I did something wrong here.
327223
1 lightyear is the distance a beam of light can travel in a vacuum in one year.  Given that the speed of light is roughly 3*(10^8) meters per second, or about 670.6 million miles per hour, then 93 million miles is about 1.58*(10^-5) lightyears.  Another way to look at it, is that it takes about 7.21 minutes for light from the sun to reach earth, and they are roughly 93 million miles apart.
406243
very long. this is because the sun is a very large star and will take billions or rather trillions of years. when it does burn out however, it will be big enough to swell so big that it will swallow mercury, venus and possibly earth ^^ good luck
205307
Daylight and sunlight are 2 different things. Daylight is obviously sunrise to sunset no matter how dark the sky may be because of clouds, rain, etc. It actually averages a bit more than 12 hours at all locations because of the width of the solar disc and refraction - sunlight bending thru the atmosphere. This adds about 15 minutes to the day at the equator where the sun to a large exent goes straight across the sky. The additional amount can be much greater around the poles though where when the sun is up it sort of circles the sky - more time near the horizon, thus more time the sun is visible (on a flat horizon) despite its actual geometric position being a bit below the horizon). Hope that is clear.\n\nYou probably mean amount of sunlight in a dry climate. That is rather site-specfic - hard to state a general amount.
324411
Mean distance from\nEarth 149.6×106 km\n(92.95×106 mi)\n(8.31 minutes at the speed of light) \n\n--\nThe Sun is the spectral type G2V yellow star at the center of Earth's solar system. The Earth and other matter (including other planets, asteroids, meteoroids, comets and dust) orbit the Sun. Different latitudes of the Sun rotate at different rates; a point on the equator takes 25 days to complete a rotation, while a point at a pole takes 36 days. The resultant torsion creates the Sun's very strong magnetic field, which in turn drives the 11-year cycle of solar activity. The Sun accounts for more than 99% of the solar system's mass. Energy from the Sun has supported almost all life on Earth through photosynthesis since the appearance of the first organisms. Humans use sunlight for eyesight, warmth, growing crops, and powering solar cells.\n\nThe Sun is a ball of plasma with a diameter of 1.392 million km (864,950 mi) and a mass of about 2.0×1030 kg, which is somewhat greater than that of an average star in the Milky Way galaxy. About 74% of its mass is hydrogen, with 25% helium, and the rest made up of trace quantities of heavier elements. The Sun is about 4.6 billion (109) years old and is about halfway through its main sequence evolution, during which nuclear fusion reactions in its core fuse hydrogen into helium. About 5 million tons of matter are converted into energy within the Sun's core every second, producing neutrinos and solar radiation. In about 5 billion years, the Sun will evolve into a red giant and then a white dwarf, creating a planetary nebula in the process.
569652
The average distance from the moon to the earth is 238,857 miles. The speed of light is 186,282 miles per second. There for the time from the light from the moon to reach earth is...\n\n238,857 miles / 186,286 miles per second = 1.28223 seconds \n\n1.28223 seconds
162749
The light had to travel 14 billion years.  Earth travels much slowly.
71063
The distance between the earth and the sun is not constant.  The earth's\norbit around the sun is nearly circular, but not perfectly so. \nOn average, the distance between the earth and the sun is 93 million miles.\nThis is not anywhere near a light-year.  It is more like 8.3 light-minutes.
15135
well, i'll answer your questions in reverse order.\n\nneptune's average distance from the sun is about 4.5 billion kilometers, or about 30 times as far out as the earth.  it has a diameter of around 50,000 kilometers, which means it's about 4 times the size of the earth.\n\nas for how long it would take - that entirely depends on what kind of spaceship you used to get there.  if you had a fictional spacecraft that could go nearly the speed of light, it would take around 3 hours.  if you used the same kind of spacecraft that the apollo missions used, you would be traveling around 25,000 MPH.  this is around 40,000 kilometers per hour, so:\n\n4.5 billion kilometers / 40,000 kilometers per hour = 112500 hours = 13 years or so.