The Earth Astronomy Our Solar System The Earth Questions What's the Earth's "absolute" speed? i.e. in relation to the central Sun, the first-order star, or related to the Universe known center of mass... How does density affect earth's layers? How fast does the earth rotate? How does this compare to the rotation of other planets? At what speed does the earth travel on its orbit around the sun? What would happen if the earth's rotation was faster or slower? How fast does earth rotate near the equator? How fast does the earth rotate per second? How fast is the earth traveling along its orbit? How fast does the earth rotate on its axis? How fast does the earth rotate in one minute? What is the formula to determine this? How fast does the earth rotate when you are at the south pole? How fast does the earth rotate in 24 hours? How fast does the earth rotate in mph and how fast does it travel around the sun in mph? In what direction does Earth rotate? Why does the speed of earth's rotation not affect us? How fast does the earth rotate around the sun compared to the other plants in the solar system? If the earth's rotation were to speed up or slow down would it have a drastic effect on the life on the planet? How does the speed of the earth's rotation compare to the moon's rotation? How fast does the earth travel around the sun? How do scientists determine the speed of earth's rotation? How did scientists determine how fast earth's orbit is around the sun? What does the earth rotate around? Why does the earth rotate from west to east? At the poles, how fast does the earth spin? Does the earth spin slower on the northern and southern latitudes ? If the earth rotates around the sun at the speed of 108,000 km an hour, why does the air in earth's atmosphere not disperse and become lost to the vast vacuum that is space? Why do we not feel the earth rotating? What makes the earth rotate? How and why does the earth spin and how fast is it spinning? Why does Earth's atmosphere rotate faster than Earth itself? How fast would something have rotate in order to create earth like gravity from centrifugal force? What causes the four seasons on earth? Do other planets experience seasons? What causes the change of the constellations with the seasons? How does latitude affect the seasons? What causes changes in the seasons and the length of the day? Why doesn't the Earth's distance from the sun cause the seasons? Why is the length of day different in different seasons? Why does the apparent daily path of the Sun changes with the seasons? What is the scientific explanation for seasons? Why it is that we have periods of night and periods of day? What causes the intensity and duration of solar radiation received at any place to vary throughout the year? Why do seasons occur? Why are there seasons on earth? What causes unequal lengths of day and night? What causes the cycle of seasons on earth? Is there a scientific name for the seasonal changes on earth? What relationship between the earth and the sun causes the seasons to occur? What are the three reasons for seasons? What causes the seasons and climate zones of the earth and why? What two factors cause the cycle of the seasons? What causes day and night and different seasons? What is earth's lithosphere made of? What is the composition of the earth's lithosphere? What is the difference between the lithosphere and the biosphere? Being that both the lithosphere & the biosphere in science research are both the outermost layer of a planets rocky surface, what sets them apart? What is the lithosphere made of? How does it compare to other planets? What is the asthenosphere? What part of the earth does it belong to? Which is thickest: the lithosphere, hydrosphere, or atmosphere? What is main difference between lithosphere and asthenosphere? What is the average thickness of the lithosphere? Why is the lithosphere rigid and the asthenosphere plastic, even though they are both part of the mantle? Where is the lithosphere thinnest? What is the lithosphere composed of? How can humans impact the lithosphere? How can movements in the lithosphere affect climate? How do the atmospheres of venus and earth differ? How do the lithosphere and asthenosphere differ? How do the lithosphere and atmosphere interact? How do the lithosphere plates move? How does the lithosphere affect earthquakes? How does the lithosphere affect human life? How does the lithosphere change? What are characteristics of the lithosphere? What is the lithosphere and why is it important? What is the lithosphere broken into? What is the lithosphere's temperature? Why is the earth's core molten and not consuming everything around it? What does the earths core do for our planet? How does the Earth's core affect Earth's atmosphere? Is the earth's core hotter than the sun? What are the 2 elements that make up Earth's core? Is the earth's core heating up? If it continues to heat up how will it effect life on the surface? Does nuclear fusion occur at the earth's core? Will our earth's core stop spinning when the sun dies? How long is the earth's core? What does the earth's inner cores look like? How deep is the earth's core? How has the earth's core stayed so hot for so long? When will it cool down? Which is hotter, the earth's core or the sun? At what rate is the earths core cooling off? And how long will it take? When will Earth's core die out? Will it die out when the sun dies out because it gets heat from the sun? At the center of the Earths core, what would the temperature be? How does the earth's core differ from other planets in the solar system? Does earth's core affect surface temperature? How does earth's core stay hot? How does earth core remain molten? How does earth's core work? How does the earth's core generate heat? How does the earth's core create a magnetic field? How does the inner core affect earth? How does the outer core affect earth? How hot is earth's core? How long will earth's core stay molten? How many miles to earth's core? What are constructive and destructive plate boundaries? What are the three main types of plate boundaries and their functions? What is a collisional boundary? Where on earth can you find a convergent boundary? What geologic feature is formed at a convergent boundary? What are three types of convergent boundaries? Is a rift valley a convergent plate boundary? What is the relationship between an ocean ridge rift and divergent plate boundary? What is subduction? What is a divergent boundary? What is the most accepted hypothesis of how the earth and moon were formed? During what time period did earth form? How do scientists think the Earth and atmosphere formed? According to the evolutionary theory, how long ago did the earth form? On the cosmic calendar, roughly when did Earth form? How close was the Moon to the Earth when it formed? If earth formed 4.57 x 10^9 years ago, what is the time in seconds? Where was the earth formed? Based on the protoplanet hypothesis, how did the earth end up being layered the way it is? How earth was formed according to the nebular hypothesis? What is the actual shape of the earth? Why is it shaped that way? How was the atmosphere of the Earth formed? When were the heavy metals in earth formed? How were heavy elements formed and how did they get to Earth? How was the earth's formation different or similar to the formation of the other planets? What was the earth formed from? How do scientists know how the earth formed? How do the four fundamental forces play into earth's formation? How was the earth formed? What evidence supports this? Why was the earth formed in layers? What events led to the formation of the earth? What is the moho discontinuity state of matter? What is the Moho Discontinuity made of? What is the moho and what is it made of? Is the Asthenosphere the same as the Mohorovicic Discontinuity? What is the Mojo layer inside the earth? How far down is it inside the earth? The moho is the boundary at what two layers of the earth? Who discovered the Mohorovicic discontinuity? What observation of seismic-wave travel led to the discovery of Moho? What separates the crust to the mantle? What is Earth's mantle? Is mantle a plasma, liquid or solid? What is the moho boundary? What two zones is the mantle divided into? Where exactly does the Moho occur? What is Moho discontinuity? How was moho discovered? How was Mohorovicic Discontinuity discovered? What does moho stand for? Why is moho important? Why is the plate tectonics theory important? Is plate tectonics a scientific law or theory? When was the theory of plate tectonics adopted? What is the difference between plate tectonics and continental drift? What does the theory of plate tectonics explain? How can the theory of plate tectonics explain how the Atlantic ocean is growing by a couple centimeters a year? What does the theory of plate tectonics state? How is the theory of plate tectonics related to the formation and breakup of pangaea? How do plate tectonics change weather and climate? How does plate tectonics affect climate change? What is earth's core made of? How does it compare to other planets? Was the early earth made of lava? What is the mantle made of? What is earth composed of? What is earth's atmosphere composed of? What is the core of the Earth made of? What is the center of the earth made up of? What is the asthenosphere made of? What is earth's lower mantle made of? What is the Earth mainly composed of? Why is the earth made of water? Why is earth made of rock? What are the three main components that make up the earth? Which elements are most common on earth? Are these elements found uniformly on other planets? Where did the early materials come from when the early earth was formed? How were the inner planets formed? What allowed earth to become hospitable for life? How do scientists know what the earth is made of? Why is earth's core made of iron? What is the difference in size between Earth and Venus? If Earth was the size of Jupiter, would humans be able to survive? Does the earth have a height? If so, what is it? Would history be different if Earth were the size of Jupiter? Would the rotation of a Jupiter sized Earth be any different, both spinning and orbiting around the sun? Would we have longer or shorter days? What is the size of the gravitational force acting on the earth due to the sun? What is the size of the Earth's surface? What percentage of the universe does the earth occupy? What is the circumference of the earth in km? What is the thickness of the earth atmosphere? How does the size of Mars compare to Earth? The Earth's diameter is about three and two-thirds times the diameter of the moon. What is the angular diameter of the Earth as seen by an observer on the moon? What is the size of earth in kilometers? What is the size of earth in miles? What does the 14 mean in Carbon-14? Given the following information, how many years have passed since the rock was formed? What is the carbon-14 dating equation? Why is Carbon 14 Dating inaccurate? How does carbon-14 dating work? Carbon-14 has a half life of 5714 years. How many years old is an artifact that contains 50% of its original carbon-14? What is Carbon 14 Dating? What is it used for? How is carbon-14 is produced in the upper atmosphere? How is Carbon 14 dating used? What is Carbon 14 radiocarbon dating? How does carbon 14 decay by beta emission? How is carbon 14 made? How can carbon 14 be used in astronomy? How carbon 14 is produced? What is the length of earth's orbit? What does the elliptical shape of Earth's orbit cause? Why is the earth's orbit elliptical? If you take millions of tons of metal off the earth in the form of satellites therefore reducing earth's specific mass, would this in turn affect the earth's orbit around the sun? What is the shape of earth's orbit? How many miles is the earth's orbit around the sun? What is earth's orbital period and rotational period? Is the sun directly in the center of earth's orbit? What is the diameter of earth's orbit in meters? How would the speed of Earth's orbit around the sun change if Earth's mass increased by 4 times? What force acts on the earth perpendicular to the force of the sun which causes the tangential accelerations characteristic of an ellipse? If the radius of the Earth's orbit around the Sun is 150 million km, what is the speed of the Earth? Why should the eccentricity of the earth's orbit make winter different in the north hemisphere than the south? What is the true shape of Earth's orbit? What is the diameter of the earth's orbit around the sun in miles? What is the circumference of the Earth's orbit around the Sun? To what effect are humans directly affecting the earth's orbit around the sun? How does earth's orbit differ from other planets in the solar system? What is earth's orbit around the sun? What is geostationary earth orbit? How does earth travel in a circular orbit? How does the earth orbit the sun? Why is earth's orbit considered to be elliptical? How can earth's orbit change our climate? How do scientists think earth's orbit relates to an ice age? How do shifts in earth's orbit affect the global climate? How does earth's orbit around the sun change over time? How does earth orbit the moon? How does earth orbit the sun? How does earth's orbit affect climate? How does earth's orbit affect climate change? How does earth's orbit affect its tilted hemispheres? Why does earth's orbit affect our climate? How does earth's orbit affect temperature? How does earth's orbit affect the seasons? How does the earth's orbit affect global warming? How does the earth's orbit effect the weather? What would happen to earth if our galaxy were to collide with another? Is astronomy in the southern hemisphere different than it is in the northern hemisphere? Why is it summer in the northern hemisphere when it is winter in the southern hemisphere? Why are annual temperature ranges in the southern hemisphere generally smaller than those in the northern hemisphere? In the southern hemisphere, would a tornado spin in the opposite direction due to Coriolis effect? From the southern hemisphere during the summer solstice, where is the sun's position in the sky? Are the constellations in the northern hemisphere ever visible in the southern hemisphere? Will a full moon occurring in New York, USA be seen at the same time in Sydney, Australia? Or does the area of the planet make full moon viewing different for different regions? Why does the earth rotate counterclockwise in the northern hemi and clockwise in the southern hemisphere? Why is the southern hemisphere warmer than the northern? Why do the southern and northern hemispheres have opposite seasons? Are different stars seen in the Southern Hemisphere compared to the Northern? What are the southern circumpolar constellations? What are the southern hemisphere constellations? What is a convergent boundary? What is the difference between a convergent boundary and subduction? What forms along divergent and convergent boundaries? What is found at a continental crust-continental crust convergent boundary? Do plate tectonics destroy the lithosphere? Where would a convergent boundary happen? How do convergent and divergent plate boundaries cause magma formation? How do convergent boundaries form volcanoes? How do convergent boundary happen? How do convergent boundaries affect the earth? How does a convergent boundary form? How does a convergent boundary move? How does a convergent boundary occur? What does a convergent boundary cause? Why does a convergent boundary occur? Why are there no stars in the background when photos are taken from space of earth? What did the earth look like 4 billion years ago and what was its condition? What will earth's continents look like in another 100 million years? What does Earth look like from deep space? How do scientists get photos of earth from beyond the moon? Why can't we get a picture of the lunar rover sitting on the surface of the moon with earth-based telescopes? Why do photos of space taken from space never show any stars? What constellation is the earth in? What did Earth look like before humans evolved? Can you see NASA equipment on the moon through a telescope? How powerful of a telescope would you need in order to view these items? What is the declination of Earth? Why are there no stars in the photos of Earth taken from space and from the Moon? What are the different layers of the earth? What is between the crust and the mantle? What does earth consist of? What is in the center of the earth? What is the Mohorovicic discontinuity and where is it found? Who advanced the theory of plate tectonics? What was Andrija Mohorovicic famous for? How did Andrija Mohorovicic discover the moho? What are P, S, and L waves? What is a P wave? How does it move? What materials can it pass through? What are a biphasic p waves? What is the difference between S-Waves and P-Waves? Why do P-waves travel faster through the inner core than the outer core? How does the p waves differ from other waves? Which way does the Earth rotate and why? Which way does the earth rotate on its axis? Does the tilt of earth affect its rotation? Which way does the earth spin, and which way does it rotate around the sun? At what angle is the earth's axis? Which way does the earth rotate as it goes around the sun? Which way does the Earth spin? In which direction does the earth rotate around the sun? Which way does the earth rotate? Why does the earth revolves* around the sun? When viewed from above the North Pole, in what direction does the earth rotate? Does the earth rotate around the sun or does the sun rotate around the earth? How fast does the earth rotate around the Sun? What direction does the earth rotate during vernal equinox? What direction does the earth rotate from the north pole? What direction does the earth rotate on a vernal equinox? What direction does the earth rotate on its axis? What way does the earth rotate and revolve? Which way does the earth rotate: east or west? How do astronomers know the earth rotates? What would happen if earth's rotation was altered? Does the atmosphere rotate with the Earth? Does axial tilt change? What is the relationship between the earth's axial tilt and the temperature patterns around the globe? How would Earth's seasons differ from current ones if Earth's axial tilt was zero degrees? What would happen if the Earth's axial tilt were to decrease from 23.5 degrees to 21.5 degrees? During which seasons are the earth's axial tilt and distribution of sunlight the same? How is the earth's tilt is responsible for the seasons? What is the current tilt of the Earth's axis? How has it changed over the last 100 years? If the earth's axial tilt were to change to 18 degrees how will it effect the seasons? How does the moon stabilize earth's axial tilt? Why does the moon stabilize earth's axial tilt? What would happen if the earth's axial tilt was zero? How does the tilt of the axis affect the Earth? If diameter of Earth changed to 120,536 km, would its distance from the Sun, axial tilt, and rotation rate change? Is earth's axial tilt responsible for the season? If the axial tilt of earth were 35 degrees, would polar regions be habitable for human life? What day/night cycle would we have if earth was tilted like Uranus? Why is Uranus Tilted on its side? How does Uranus' tilted axis affect its seasons? How does axial tilt affect climate? How does axial tilt affect seasons? How does axis tilt affect day length? How does axis tilt affect sun angle? How does axis tilt affect sunlight intensity? How does the axial tilt affect life on earth? Considering the Big Bang Theory, how was the earth formed? Why is the formation of the Earth a controversial topic? Approximately how old is the Earth? How is this age determined? What are three theories on how the earth was formed? How do evolutionists believe the earth was created? What year was the earth formed? How was the earth created according to the Big Bang Theory? What time period was the earth created in? How long did it take for the earth to form into a hospitable place for life? What features of Earth allow it to sustain life? When was life formed on earth? Could humans survive on other planets in the universe? Why was the earth created? If the entire history of earth was summed up in 24 hours, how long will humans have occupied the planet? How long would mans history on earth be if the timeline were 24 hours? What gasses did the extensive volcanic eruptions add to the atmosphere in the early in the history of Earth? If the entire history of the earth was relative to 1 day, how long would humans been around on earth? If the history of the earth represented one year how many days would human evolution occupy? For what percentage of Earth’s history has life existed on Earth? How is the mass of the earth calculated? How do rocks provide a history of the earth? How do scientists know what the earth was like after its formation? When will the world end? What is earth's current life expectancy? What is the lifespan of the earth? What is the life span of planet Earth with scientific predictions and humans taken into account? How does the earth revolve around the sun? Is the earth slowly getting closer to the sun as it orbits it? If not, what keeps it from being drawn into the sun? What evidence supports the earth revolving around the sun? What observation provides the best evidence that Earth revolves around the Sun? In what direction does the earth revolve around the sun? Does earth have seasons because its axis is tilted as it revolves around the sun? How would you calculate the speed at which the earth revolves around the sun in m/s? As Earth revolves around the Sun, how does its axis of rotation change relative to the Sun? How does this affect the seasons? How was it proven that the earth rotates around the sun? What is unique about how the earth orbits the sun? What causes the earth to revolve around the sun? How did astronomers prove the earth revolves around the sun? What allows the earth to rotate around the sun? How fast does the earth orbit the sun? How does the apparent path of the sun change as the earth revolves around the it? How does the position of the earth as it revolves around the sun affect the seasons? How would earth be affected if its orbit around the sun were slower or faster? Which factors affect how stars appear from Earth? What caused Pangaea to break apart? When will the next supercontinent form on earth? Was pangea one solid continent or made of small islands that fit together? If it was one solid continent was it all formed at once by molten rock coming up from the earth? How does Pangaea differ from Gondwana and Laurasia? How did Pangaea affect life? How did Pangea change over time? Where do convection currents form? What do convection currents do? What causes the global air convection current between the equator and the poles? What will happen to the convection currents in the mantle if the Earth's interior eventually cools down? What causes convection currents in the mantle? What are convection currents and how do they relate to the movement of the tectonic plates? What is the purpose of convection currents? Why does a convection current move in a circular motion? What are convection currents and what causes them? Why do convection currents in the earth's mantle turn left once they stop moving upwards? Why do convection currents occur within the earth? How are convection currents important in the earth system? How do convection currents change the earth features? Given the following information, does that mean the Earth will eventually change its axis of rotation to the vertical? Due to the precession of the earth, in which constellation will the vernal equinox occupy next? What is nutation in relation to earth? Is it possible that in 13,000 years it will be summer in December in the northern hemisphere? Or do we artificially change the definition of the length of the year to ensure this never happens? How do astronomer explain precession of the equinoxes? How long is the precession of the equinoxes? What causes precession of the equinoxes? What is precession of the equinoxes? Why is it called the precession of the equinoxes? Suppose the Earth's axis had no tilt. Would we still have seasons? What is the difference between a sidereal year and a tropical year? How is each calculated? If the earth is about 4.6 billion years old, how many precision cycles have occurred? The Vernal Equinox is in which constellation? How long does it take the earth to make complete turn on its axis? How are the number of days in a year related to astronomy? Why do the stars appear to rotate around Polaris? What does mean when scientists say the earth wobbles? What is the outer core made of? Is the outer core made of metal? Is the outer core made of iron and nickel? Is the outer core made of solid metal? What elements are found in the earth's core? What are the inner and outer cores made of? What are the main components of the outer core? How was the inner core formed? What separates the inner core from the outer core? Why do scientists classify the earth's core into an inner and outer layer? Why is the outer core made of liquid? Why is the outer core made up of liquid rock? What is perihelion and aphelion of earth? And according to physics, Earth orbits faster when it is nearer the sun than when it is farther. Does this, in any way, affect the length of day in the earth? When will perihelion coincide with the June solstice? When this happens, will the average global temperature rise, fall, or stay the same? At perihelion, the sun where are the sun's rays concentrated? Why is it, when you see the earth from space, there are no stars in the background? What causes this, and why? What is the Half life of carbon 14? What does the half life of carbon 14 mean? How is this useful in the field of astronomy? Why is earth considered to be in the Goldilocks Zone? How far above the Earth does Earth's atmosphere end and space begin? What are the four major divisions of Earth? What are pivotal events in the earth's history? What can rocks tell us about Earth's history? What are the major eras of earth's history? Why are the last 570 million years of Earth's history divided into three different eras while the preceding four billion years comprise only one era? What are two events associated with the impact of a comet or an asteroid with Earth that would cause a major extinction of life? Is it true that Earth's history has always had periods of hot and cold weather? What percent of the history of life on Earth have humans existed? What are the five eras in Earth's history? How did prokaryotes early in Earth’s history alter the environments on Earth? How does earth history differ from other planets in the solar system? How do sedimentary rock show earth's history? How do fossils tell us about earth's history? How do rocks record earth's history? How do scientists divide earth's history? How do astronomers study earth's history? How do we learn about earth history? How do we measure earth's history? How does knowing the history of the earth relate to the concepts in evolution? How has water changed earth's history? What is earth's history? How and why was the earth formed? How was the world created? How was the magnetosphere created? How was the earth magnetic field created? Why is it so important? How was the world created according to science? Is there any overlap between religious views of how the world was created and scientific theories? How do astronomers believe the world was created? What led to the creation of the earth's atmosphere? How do scientists believe the Earth was created? How many theories exist about how the earth was formed? What keeps the earth's atmosphere from dissipating? How are the seasons formed? How do scientist theorize the earth was created? How do scientists know how the earth was created? What was the probability that a planet like earth would be created after the Big Bang? What are the chances another planet like earth exists? How was earth created considering a scientific mindset? What created earth's early atmosphere? What created earth's magnetic field? What created earth's oceans? What created earth's atmosphere? What was earth created by? What happens when the speed of rotation of the earth slows down? Is the earth’s axis always in the same plane? Does the tilt stay the same? What does this effect? What is the Tropic of Capricorn and Tropic of Cancer? Why are they so important? When was one year in our calendar worked out and by who? Did they base it on the tilting of the Earth or the orbit? What is the force called that makes the earth axis tilt, during its orbit around the sun? How long is a earth day to the exact second? What are the layers of the earth made of? Is the center of the earth hot? What is the crust of the earth made out of? What is the mesosphere made of? What are the main components of the atmosphere? What percentage of the earth is made up of water? What is the earth made of? How does earth's composition compare to other planets? Which part of earth is made of solid iron and nickel? What are the earth and moon predominantly made of? Earth’s crust is made up of mostly which two elements? How can we tell what the earth core is made of? How do we know what the earth interior is made of? How do we know what the earth made of? How were the materials that make up the earth come into being? What caused the earth to become round in shape? What caused the formation of the earth's layers? How many elements is the earth made of? How many layers is the earth made of? How did the components of the earth come together to form the planet? How much oxygen is the earth made of? Why is the earth made up of different layers? How fast is the Earth traveling through space? Does Earth have a ring of debris? Throughout Earth's recorded history what is the hottest and the coldest temperature ever recorded? What parts of the Earth had these temperatures? When did life begin? How did life begin on Earth? On Earth, where did life began? When did plant life begin to appear on earth? Where and when did human life on earth begin? How did life begin according to science? How long ago did life begin on earth? How did life begin on the planet earth? What were the odds that life would begin on earth? When did life originate on Earth? Why does life not exist on other planets like our planet earth? What are the theories about how life was formed on earth? According to the scientific view, how many years ago did life on earth begin? Did life originally begin in the ocean? How did human life start on earth? When did animal life begin to appear in the oceans? How did life begin on earth according to evolution? When did animal life begin on earth? When did plant life begin on earth? When did primitive life begin on earth? When did simple life begin on earth? How long has life existed on earth? Why did life begin on earth using an anaerobic mode of metabolism? Why do earth rotate and revolve ? Peshawar in Pakistan and Columbia in SC, USA are at the same latitude #54^o N#. Their longitudes are #71.7^o E and 81.1^o W#. The radius of the Earth at this latitude is nearly 6371 km. How do you find the latitude-circle distance between the two cities? How does the moon orbit vary with time? Assuming that the Earth is a sphere and its orbit around the Sun is a circle, how do you find the volume of the torus that is just sufficient to accommodate the Earth? Along the equator, it was no-shadow-noon on September 22 ( Autumnal Equinox). When do you expect this right-above-head-Sun noon, at Bangalore, India? The latitude of Bangalore is #12.98^o N#. How would you describe the internal structure of the earth? How do we know that the structure of the earth exists? Which portion of the earth has the thickest structure? What indirect evidence do geologists use to study the structure of the earth? What causes the layered structure of the earth? How do seismic waves provide evidence for the earth's structure? How would you briefly explain the structure of the earth? How did scientists discover the internal structure of the earth? How does the structure of the atmosphere affect life on earth? How does the structure of the earth affect us? What tool have scientists used to help make inferences about the interior structure of earth? What was the first form of life on Earth created from? When did the first life arise on earth? When did multicellular life begin to appear on earth? What was the first plant life and animal life and when did it appear on earth? Were the very first life forms on earth aerobic or anaerobic? What was one necessary condition for the evolution of the first life on earth? Were the first life-forms on earth prokaryotic cells or eukaryotic cells? What was the first life that appeared on earth? When did life appear on earth? How long did it take to evolve from non-living systems? Where did life on Earth come from? Did life on Earth originate from the ocean or on land? Where did early life forms get their energy? Could a virus have been the first life form on earth? Where did the first living things on earth come from? What was the beginner of life on earth? What was the first life form on earth? How did the first life form on Earth know how to reproduce itself? What modern organisms are thought to be most like the first life-forms on Earth? We all know that the first life on earth is the single celled plant, but how did it come into existence? What is most likely the ultimate fate of the planet Earth? About how long do astronomers think it will be until the Earth is destroyed? Why did life originally begin in the ocean? How did cells first appear on earth? What came first in the formation of earth? When was the earliest proof of human presence on earth? What were the first living things on earth? How long ago did they appear? What was the first continent on earth? What is a brief description of how the earth was formed? What was the temperature of the earth when it first formed? What is accretion, and how does it relate to the formation of the Earth? How was gold formed in the earth? How were the earth's oceans formed? How close was the Moon to the Earth during it's formation? When was the atmosphere of the Earth formed? Why was the atmosphere of the Earth formed? What caused the atmosphere of the Earth to form? How long ago was Earth formed and how does anyone know that for sure? What phenomenon contributed to the formation of earth's atmosphere? What phenomenon contributed to the formation of earth's configuration? What phenomenon contributed to the formation of earth's shape? What phenomenon contributed to the formation of earth's layers? What phenomenon contributed to the formation of earth's craters? How did the earth form? When did the earth form? Question #ad590 Question #a22c3 Question #6f275 What makes the Earth unique among the planets of the Universe? When does an equinox occur? How can there be life on earth? How did life start on earth? How has life on earth changed? How did life on earth develope? How is life on earth organized? How did life on earth originate? How is seismic discovery important to us? How did Mohorovicic discontinuity get its name? What does the Mohorovicic discontinuity separate? What is Mohorovicic Discontinuity made of? What is the Mohorovicic Discontinuity and how was it discovered? Why is the Mohorovicic Discontinuity important? What is the deepest anyone has dug into the earth? What are the temperatures of each earth layer? Where is the earth when it travels the fastest? Is planet earth closer to the sun during winter solstice or farther? Where is the earth's ascending node located? What if the Earth's axis were tilted 90° to the ecliptic? What is the relationship between Plate tectonics and mountain formations/earthquakes/volcanoes? How does tectonic plate motion relate to the formation of volcanoes? How did tectonic plates help shape the early earth? How did tectonic plates affect the early atmosphere? What type of surface movement existed before plate tectonics? How did the tectonic plates first form? How have tectonic plates changed the earth? What does a tectonic plate consist of? How are tectonic plates able to move? How are tectonic plates moved by convection currents? How do tectonic plates move in different directions? What are the tectonic plates made of? What are tectonic plate boundaries? Question #4e884 If the Earth's axis of rotation was inclined at 90 degrees what would happen? 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