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Quickie Questions - Extraordinary Earth - Movement of the Earth

Date Answered Questioner (age, location) Question Answer

January 13, 2010Vinny (age , ) Let's look at a particular motion of Earth's axis, the precession or axial rotation (Earth wobbles on it axis as it spins, completing a full wobble every 23 000 years). This was explained by Newtonian physics. Earth has a nonspherical shape, bulging outward at the equator. The gravitational tidal forces of the Moon and Sun apply torque as they attempt to pull the equatorial bulge into the plane of the ecliptic.
January 11, 2010rachael (age 10, ohio) I you were in a space ship looking down at the earth would you see the earth rotate? Absolutely! It will complete a full rotation in 24 hours!
October 19, 2009monica (age teacher, ohio) How do we know earth rotates west to east? One of the most important clue is that the Sun rises from the east and sets on the west.
October 2, 2009mabidka (age 17, Pakistan) what is the direction of earth rotationi i.e north, south, east, west? The Earth rotates towards the east. As viewed from the North Star Polaris, the Earth turns counter-clockwise.
September 30, 2009t (age 29, England) Because the Earth gains an extra day every four years. Does this mean it gains an extra week every seventh leap year. Because a year in our planet is not an exact multiple of 24-hour days, the leap years account for the resultant difference. It is not that a new day is added every 4 years, or a week every 7 leap years, we are just "compensating" for the difference.
September 25, 2009Jacqueline (age 9, philippines) why we can't feel the earth is moving? Because we are so small and moving on its surface along it, that we can't easily see the motion. But the day-night cycle, the seasons, the apparent motion of the stars, etc. are clear indication of the Earth motion.
September 25, 2009AUGUSTINE (age 55, KERALA/INDIA) Why is earth's orbit around sun elliptical? Due to the fact that all gravitational interactions with other objects in the solar system can disrupt a perfectly circular orbit, elliptical orbits are the norm (circular orbits are rare). However, the Earth's orbit, with an eccentricity of only 0.02, is very circular.
August 19, 2009darren (age 34, australia) does the earth move off its orbit around the sun at all, even slightly? Your question is not clear. Orbit, in a very simple definition, is the path that a planet follows around the Sun. There are simple aproximations (circular orbits), no so simple (elliptical orbits) and very complex ones to describe the motion of a planet around the star. See, for example, this page for some motions of our planet, and this one for background information.
April 16, 2009sirana (age 6, queensland, austlia) we do we have night time and day time sir????? and why do we call it that sir??? i love the night time because i see the stars very bright were i live. why is that sir??? The succesion of days and nights are due to the rotation of the earth around its own axis. This happens because the side that our planet shows to the Sun is always changing due to this rotation.
April 13, 2009Ana (age 29, Germany) "What force makes earth to spin around its axis, but around the Sun?" The rotation of the Earth, and other planets, about their axis is a remanent of the rotation of the planetary nebula from where all were formed.
March 4, 2009Jenna (age 13, united states) Explain the rotation of the earthon its axis and its connection to our day and night. The Earth rotates around once in 24 hours. The time it takes for the Earth to rotate completely around once is what we call a day. It's Earth's rotation that gives us night and day. MOre information on our web page The Earth's Rotation .
February 24, 2009jim (age 68, pa usa) how many miles a day does the earth travel (move) from december 21 to march 21(91 diferent answers) from north to south is 1616 miles The differences could be related with the different assumptions made. For example, using an average distance Sun-Earth of 150 million kilometers (93.2 million miles), we can obtain the lenght of the circunference multiplying by 2 Pi, which gives 585.6 million miles for the circumference. Dividing this by 365.25 days/year gives 1.603 million miles per day (in average, since the orbit is silghtly elliptical).
February 24, 2009Alan (age 12, michigan) How do the earth rotate? The Earth rotates towards the east. As viewed from the North Star Polaris, the Earth turns counter-clockwise.
February 18, 2009kiryn (age 10, usa) how fast does earth rotate? The speed at which the earth spins varies upon your latitudinal location on the planet. Athe equator, where the circumference of the Earth is greatest, the speed is about 1 670 km/h, or 1 038 miles per hour
January 22, 2009meyar (age 8, uae) how are days sometimes long sometimes short? It depends on the season and latitude you are at. For low latitudes, near the equator, the lnght of the day will stay roughly the same along the year. For a background information see our web page Earth's Tilt Is the Reason for the Seasons!. Winter (for the Northern Hemisphere!) is represented by the top figure of this page. There you can see that due to the Earth's tilt, a wider area of our planet is on the dark side, corresponding to the well known fact of longer nights and shorter days for this season.
October 1, 2008yagaira (age 17, usa) what is the position of the earth during the summer solstice? The summer solstice occurs when the tilt of the Earth's axis is most oriented toward the Sun, causing the Sun to reach its northernmost (North Hemisphere) and southernmost (South Hemisphere) extremes. More information can be found on our web page The Summer Solstice.
September 26, 2008Waleed (age 37, the UK) As far as I know, the Earth is accelerating when it is approching the Sun i.e passing the Periheilon. Why we do not feel the accelration? Why no Tsunamy happens every time the Earth changes its speed.. Our planet orbit has an eccentricity of 0.017, which means our orbit is very close to a circular shape. Therefore the assumed change of speed, which on top of this happens over a considerable amount of time (making the value of the acceleration very low) is not really significant.
September 25, 2008Julia (age 53, New Mexico, USA) Does the earth move at a constant velocity about the sun, throughout the year? I heard that it speeds up when it is closer to the sun. Is this just an apparent increase in speed like if you are at a race track and the cars seem faster when they are going right past you, or does gravity have a slingshot effect? No, Earth's (and any other planet's) speed changes with the distance to the Sun. This is clearly captured by Kepler's laws, especifically Kepler's equal-area law: The line connecting a planet to the sun sweeps out equal areas in equal amounts of time.
July 8, 2008michael (age 16, Phoenix, AZ) Can you explain to me each of the three major movements of the Earth, as well as the effect of the Earth's tilted axis Earth has two important movements. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. The third movement is related with Earyh's axis. Earth's rotation axis is not fixed in space, its direction executes a slow precession with a period of 26,000 years.
July 7, 2008RAVEN (age 13, usa) What is the vernal equinox? Seasons are related with the tilt of Earth axis. The dates of maximum tilt correspond to summer and winter solstice, and the dates of zero tilt to the vernal (spring) and autumnal equinoxes.
June 27, 2008 (age , ) What causes stars to appear to follow circular paths in the night sky? That the stars appear to follow daily circular paths around Polaris is the best supporting evidence that the Earth rotates on its axis.
April 2, 2008Rosa (age 46, WA. USA) Is there a third movement of the earth around the sun? There is one that ocurres evry 24 hrs. and the other every 365 1/4 days, but what about the tilting away and towards the Sun at the same time? The Earth's rotation axis is not fixed in space, its direction executes a slow precession with a period of 26,000 years. See this page for more information.
March 19, 2008Per (age 69, Sweden) The eccentricity of Earth's orbit changes due to interaction from the other planets, but the major axis remains the same (I have heard). How comes? A significant change in eccentricity will result in a change of the semi-major axis. This animation, developed by Randy M. Russell, part of the Windows to the Universe team, will give you a clear visualization of these changes.
March 18, 2008Courtney (age 11, mass) How fast is the Earth moving? The Earth completes a full orbit (approximately 940 million km) around the sun in about 365 days (a year). Considering that each day has 24 hrs, it follows that the translational speed of our planet around the Sun is about 107 305.9 km/h or 1 788 432.2 m/s.
March 11, 2008kareen (age 9, phila pa) How does the sun orbit the earth? All planets, including Earth, orbit the Sun following an elliptical path.
January 12, 2008christopher ( US Michigan) In which direction does the earth spin? As seen from the North Pole, our planet spins in a counterclockwise direction (and also travels around the sun in an counterclockwise orbit).
January 1, 2008ina (Singapore) what direction does the earth rotate?east to west or west to east?and which direction (nort,south,east or west) is the axis of the earth slanted? The Earth rotates on its axis from West to East, and its axis is slanted about 23 degrees from the vertical.
December 27, 2007zul (malaysia) what s the effect when earts rotates on its axis The rotation of a planet on its axis is the cause of day and night.
December 17, 2007Karyn (Wisconsin) Why do we not feel the Earth's movement as it rotates? If you close your eyes when riding a car on a very straigh and very smooth road, you won't feel the motion. That is the same reason we don't feel Earth's motion.
November 7, 2007Antony (Somerset in England) Are there any variations in the earth's orbit?
My question is prompted by the evidence of the 1500 year global warming cycle but with no corresponding matching cycle of changes in the sun's radiance. I am asking if the sun/earth distance has occasional variances?
Yes there are, and its relaton with our planet climate is called The Milankovitch Theory. Please, visit this NOAA page for more information.
November 5, 2007sujakrishnan (India) Does the Earth moves in a North South direction? Yes, this "buoyancy" motion is one of many small motions of our planet. The two more important are the motion around the Sun and the rotation around its axis.
September 17, 2007bree-ann (australia) how long does it take the earth to orbit the sun? One full orbit around the Sun is the definition of a year.
August 21, 2007Taylor (New zealand) How long does it take for the Earth to complete one orbit around the Sun? One full orbit of our planet around the Sun takes one year.
July 6, 2007Bob (usa) What is the shape of the Orbit that the Earth gose around the sun? Like all planets in our solar system, the Earth is in an elliptical orbit around our Sun. In Earth's case, its orbit is nearly circular, so that the difference between Earth's farthest point from the Sun and its closest point is very small. More information in our webpage The Earth's Orbit.
July 3, 2007corey (Maryland) how does the earths rotation affect us? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.
May 30, 2007ABDUL (QATAR) why sun rises in the east? If we imagine the Earth to be at the center of a large sphere (the celestial sphere), where the Sun, stars, etc. are located; because the Earth is rotating from west to the east, everything on the celestial sphere will apparently move from east to the west.
May 10, 2007abu (Canada) What causes seasonal changes?? During the year, the seasons change depending on the amount of sunlight reaching the Earth as it revolves around the Sun. The seasons are caused as the Earth, tilted on its axis, travels in a loop around the Sun each year. Summer happens in the hemisphere tilted towards the Sun, and winter happens in the hemisphere tilted away from the Sun. As the Earth travels around the Sun, the hemisphere that is tilted towards or away from the Sun changes. The hemisphere that is tilted towards the Sun is warmer because sunlight travels more directly to the Earth’s surface so less gets scattered in the atmosphere. That means that when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere. The hemisphere tilted towards the Sun has longer days and shorter nights. That’s why days are longer during the summer than during the winter. More information in our web page Earth's Tilt Is the Reason for the Seasons! and the links therein.
May 5, 2007Smriti (India) Why does earth rotate about its own axis? The rotation of the Earth, and other planets, about their axis is a remanent of the rotation of the planetary nebula from where all were formed.
March 7, 2007Rosemarie I am not sure what you mean by a model of the Earth's eccenticity, so here are some considerations: The orbit of the Earth is not a circle, but is very close! In mathematics, eccentricity is a parameter associated with every conic section. It can be seen as a measure of how much the section deviates from being circular. In particular, the eccentricity of a circle is zero, and the eccentricity of a (non-circle) ellipse is between 0 and 1. For our planet this parameter is 0.017, meaning an orbit very close to a circular shape.
March 7, 2007Annnaleise (California) What determines a year? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year.
March 7, 2007achsah (NY/U.S) How does the movement of the earth cause day and night? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights (because every time shows to the Sun a different side of the Earth). The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.
February 28, 2007vanessa (philippines) why are there places w/c have different seasons and what are the effects of the rotation and revolution of the earth and its connection to this seasons? In more or less degree thare are seasons all around the planet. The four seasons are better define at mid-latitudes. The tilt of Earth's rotational axis and the Earth's orbit work together to create the seasons. As the Earth travels around the Sun, it remains tipped in the same direction, towards the star Polaris. This means that sometimes the northern half of the Earth is pointing towards the Sun (summer), and sometimes it is pointing away (winter). A complete explanation of the seasons can be found in our web page The Seasons.
February 5, 2007jet (Philippines) what are the structural features of the earth's movement? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.
February 5, 2007YAM (Philippines) what are the structural features of the earth's movement? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.
January 29, 2007Larry (IN/USA) Why does the earth move like the way it does and will it ever change in the future because me and my brother have a bet i say that it will probbly never and he says it will The answer to your question starts with the Big Bang. Matter spun off of this original explosion (much like water spins in smaller circles when you swirl your hand through it). Scientists believe that the solar system was formed when a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star (called a supernova). This explosion made waves in space which squeezed the cloud of gas and dust. Squeezing made the cloud start to collapse, as gravity pulled the gas and dust together, forming a solar nebula. The planets and moons were formed from this solar nebula. The Earth and other planets continue to spin unless acted on by an outside force (a big comet hitting the planet, etc).
January 19, 2007Joey (N.J./US) How does winter solstice work? Due to the rotation of our planet around the Sun, the position of the Sun in the sky changes, in the north-south axis, over the course of the year due to the changing orientation of the Earth's rotation axes with respect to the Sun. The dates of maximum tilt of the Earth's equator correspond to the summer and winter solstice, and the dates of zero tilt to the vernal and autumnal equinox. In the northern hemisphere, the Winter solstice is day of the year (near December 22) when the Sun is farthest south
January 19, 2007Joey (N.J./US) How does winter solstice work? Due to the rotation of our planet around the Sun, the position of the Sun in the sky changes, in the north-south axis, over the course of the year due to the changing orientation of the Earth's rotation axes with respect to the Sun. The dates of maximum tilt of the Earth's equator correspond to the summer and winter solstice, and the dates of zero tilt to the vernal and autumnal equinox. In the northern hemisphere, the Winter solstice is day of the year (near December 22) when the Sun is farthest south
January 14, 2007Brandon (findlay) how dose day and night occur There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.
January 3, 2007dennis (durham england) howmany miles does the earth travel around the sun in one year? Although earth's orbit is an ellipse, the difference between the major (1 AU) and minor(0.983 AU) axes is minimum, and we can take the orbit as a circle with a radius = 1AU = 93 million miles. The circumference = 2*Pi*r = 2*22/7*93*10^6 = 584.57 million miles (roughly).
December 27, 2006stefanie (maine) what does rotation mean? In a planetary sense, Rotation is a complete revolution around the planet axis. For example, the rotation period of our planet around its axis (Length of Day) is 24 hrs, and its revolution period around the Sun (Length of a Year) is 365 days 5 hrs.
December 20, 2006Roxanne ( England) Is the eath's orbit a perfect circle? Although the orbit of the Earth is not a circle, it is very close! In mathematics, eccentricity is a measure of how much the orbit deviates from being circular. In particular, the eccentricity of a circle is zero, and the eccentricity of a (non-circle) ellipse is between 0 and 1. For our planet this parameter is 0.017, meaning an orbit very close to a circular shape.
December 20, 2006amber (england) why do we have night and day? There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year.
December 20, 2006Leah (Australia) My teacher is asking to research the rotattion of the earth? Can you please help me? Earth has two important movements. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year.
December 13, 2006Rebecka (Michigan) How many mph does the Earth go around the sun? The orbital speed of our planet is 29.8 km/s (~ 66 514 miles/hour)
December 11, 2006Ashley (Texas USA) How does the seasons change on Earth. The seasons are caused as the Earth, tilted on its axis, travels in a loop around the Sun each year. Summer happens in the hemisphere tilted towards the Sun, and winter happens in the hemisphere tilted away from the Sun. As the Earth travels around the Sun, the hemisphere that is tilted towards or away from the Sun changes. More information can be found at our web page Earth's Tilt Is the Reason for the Seasons!
December 9, 2006Dagmawit (Canada) What makes Day and Night There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights. The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year.
December 6, 2006Aimee (Connecticut) How far is Mercury from Earth? Because all planets are constantly rotating around the Sun, it is useful to establish a frame to determine the average distance between two of them. Let’s assume for this calculation that Mercury and Earth are aligned with the Sun, and use their average distance to the Sun to determine the average distance between them: Mercury average distance to the Sun: 57.9 million km (36.0 million miles) Earth average distance to the Sun: 149.0 million km (92.8 million miles) Difference (average distance between the two planets): 91.1 million km (56.8 million miles)
November 27, 2006michael (united states of america/north america) how far is the moon from the sun? Because the Moon revolves around the Earth, the average distance to the Sun is the same for both: 149 000 000 km (92 800 000 miles)
November 27, 2006MANVI (delhi/india) what is occurance of day and night? Our planet has two important movements: the rotation of the Earth around its axis, which takes about 24 hours to finish. This rotation is the cause of days and nights. The second is the revolution around the Sun. One revolution takes 365 ¼ days, or one year.
November 12, 2006Maya (Indiana) What do you call the earths movement around the sun? Is it called "Orbit" The two main movements of the Earth are the rotation of the Earth around its axis (it takes 24 hours to complete one rotation), and the revolution of the Earth, or orbital motion, around the Sun (which takes 365 ¼ days, or 1 year, to complete).
November 9, 2006Selina (Australia) What is the exact distance from the earth's equator to the sun in km's? The slightly elliptical orbit of the Earth around the Sun causes the Earth-Sun distance to vary along the year. The average distance has been calculated to be 149 476 000 Km.
October 23, 2006nompumelelo (south africa) how many days does the earth revolver around the sun The period in which our planet completes a revolution around the Sun is 1 year (365 hrs 56 min). For more interesting information and statistics about the Earth, visit our webpage Earth
October 23, 2006Ajitha (Algonquin) What is the distance between the earth and moon?
How much time does take per revolution?
Dear Ajitha The distance between our planet and moon changes continuously, but it has been calculated that the average Earth-Moon distance is about 385 000 km. Now, the period in which the Moon completes a revolution around the Earth is exactly 27.321661 "Earth days", commonly expressed as 27.3 days. Thank you for visiting Windows to the Universe.
November 21, 2000 Jarald (Ohio, USA) Why do seasons occur? Most people think the seasons are caused by the Earth being farther away or closer to the Sun. But, it's actually the tilt of the Earth and the motion of the Earth about the Sun that causes the seasons! Check it out!
September 26, 2000 Jess (New Zealand) Do the chairs on a merry-go-round rotate or revolve? Chairs on a merry-go-round revolve around the center of the ride, just like the Earth revolves around the Sun! If each chair spun around itself, then the chair would be rotating.
June 26, 2000 Julie (California, USA ) Is Earth upside down?

Interesting question! The answer is no - sort of. You see, the Earth is almost a perfect sphere in a vast area we call space. In order for Earth to be upside down, we would need to decide which way is up in space.

The problem is, space is bigger than we can imagine. We have no idea how big it is or which direction "up" would be.

In other words, no, Earth is not upside down. Although, I don't think you could say it is right-side up, either.

May 8, 2000 Rachel (New York, USA) What is the degree of the Earths axis? The Earth's axis is tilted 24 degrees.
May 8, 2000 Chris (United Kingdom) Does the Earth rotate around the Sun clockwise or anti-clockwise? The Earth revolves around the Sun in a counter-clockwise direction. Actually, all the planets in our Solar System revolve around th e Sun in the same direction.
December 24, 1999 Kevin(Canada) what is a solstice The winter solstice is the shortest day of the year, while the summer solstice is the longest. Both of these are caused by the Earth's movement around the Sun.
November 29, 1999 Will (Virginia, USA) We know that the earth will pull on the moon as the moon pulls on the earth. Does rotation of the moon the affect the rotation of the earth? And if so how profoundly does it the earth's rotation? The rotation of the Moon does affect the rotation of the Earth. The Earth is slowed down by about 1.5 milliseconds per century. Eventually, the Earth will be slowed down enough that the same side of the Earth always faces the Moon, just as currently the same face of the Moon always faces the Earth.
November 5, 1999 Sarah (California, USA) What planet spins so fast that it bulges at its equator? The Earth does! This is because objects tend to move out from the center when you spin them...like when you spin in a circle, your arms just want to fly out!
February 3, 1999 Carol Has the earth's rotation ever speeded up in the past? Actually, over time the rotation of the Earth has gradually slowed down. Eventually its rotation will be in synch with the Moon's rotation, as the Moon is synchronous with the Earth's. The Earth slows by about 1.5 milliseconds/century.
January 21, 1999 Rennie What happens if the earth's revolution around the sun is changed to go the opposite way? For example say the earth revolves in a clockwise position and is changed to counter clockwise. Will night become day? is time affected? gravity? If the Earth were to revolve in the opposite way around the Sun, time and gravity would not be affected, as time is measured by the presence of change, and gravity is caused by the mass of the Earth, which would not change. Day and night would not change because that is cause by the Earth's rotation on its axis, but the seasons would. For example, if it was the beginning of spring, you would go back into winter again, then fall.
January 8, 1999 Randy What caused the Earth to wobble? What caused the Earth to tilt? The wobble is mainly caused by the Sun, Moon, and the larger planets, which apply a torque to the Earth. Other effects are caused by the movement of the Earth's crust and by air mass movement.
It is theorized that the reason the Earth is tilted on its axis is that soon after it was formed, it was hit by a large body.
May 22, 1998 Joseph (Pennsylvania, USA) Why does the earth spin? I know that it has always been spinning, but what started it? Why does the moon not spin? Does it have to do with gravity? Well, the answer to your question starts way back with the Big Bang. Matter spun off of this original explosion (much like water spins in smaller circles when you swirl your hand through it). The Earth and other planets continue to spin unless acted on by an outside force (a big comet hitting the planet, etc).

The Moon actually does spin. It rotates just once as it orbits the Earth. This is the reason we always see one side of the Moon.

May 4, 1998 Jeremy (New York, U.S.A.) What would happen if the Earth started rotating backwords? For that matter, why is the Earth rotating in the direction that it is anyway? If it reversed direction, would anything happen? Would time reverse as well? The Earth has been rotating the same direction ever since it formed. Since it was formed from swirling matter, it just kept moving in the same kind of spinning motion. As for the direction, there is no real reason the Earth has to be spinning the wa y it is. Several planets spin the other direction (relative to their orbital motion). If Earth were spinning the other way, we would just have sunrise in the West and sunset in the East.
April 14, 1998 Anne Rachel (Philippines) If two planes flew at the same airport and traveled around the world at the same speed and altitude and landed in the same airport but different direction, who will arrive first, the one who went westward or the one went easatward? Because the rotation of the Earth is toward the east, the plane going against the rotation, or the plane going west, would return to the airport sooner.
March 24, 1998 Lisa ( Michigan, USA) Do mountains have any effect on the rotation of the earth on its axis? As far as 'balancing it out'. Mountains have little or no effect on the rotation of the Earth. Compared to the diameter of the Earth, mountains are no more than a roughness on the surface. If you look at a textured globe, you can see and feel that the mountains are no more than small bumps compared to the Earth.
March 13, 1998 Nasser (Oregon, USA) At what earth rotational speed we will be thrown off into space, i.e. gravity can't keep us here on earth. In order to throw us off the Earth at the equator, that is, to completely overcome the effects of gravity there, the Earth would have to rotate 806.4 times every day.
February 10, 1998 Tamarra (Rhode Island, USA) I live in New England. During the winter months, are we closer to the sun or further away? My husband and I have a bet. I say we are closer to the sun in the winter. Well, Tamarra, you win! The Earth is in fact closer to the Sun during the winter, a good clue that being closer to or farther from the Sun has little to do with the changing seasons.
January 26, 1998 Scott (Maine, USA) How and why does the earth spin, and how fast? The Earth has been spinning since the beginning of the Solar System, when it was formed. Since it is already spinning, it will continue until something stops it. This is called the conservation of linear momentum.

The rotational speed of the Earth depends on where you are. At the equator, the speed is about 1670 km/hr, or 1070 mi/hr. To find the rotational speed where you live, take the cosine of your latitude, and multiply it by the speed at the equator. For example, the speed at a latitude of 60 degrees, the speed would be cos(60)x1670=835km/hr.


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