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I do not think you even know the definition of science. You and him should get a room together, then pseudoscience will flow endlessly
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Fair question.So the moon is inverted in the Northern vs Southern hemisphere of the globe at the same time and same moon phase, more proof the Earth is a sphere. Also constellations are inverted in the opposite hemisphere, explain this please flat Earthers...
They are angled away, it's just that they're angled by an amount that is...wait for it...too small to see.
They are angled away, it's just that they're angled by an amount that is...wait for it...too small to see.
This is the Verrazano-Narrows Bridge, in New York City:
Source: File:Verrazano-Narrows Bridge @ Night from Brooklyn.JPG
With the curvature of the earth as it is, the span of the bridge is long enough, and the towers tall enough, that the tops of the towers are 1-5/8" further apart than their bases. Can you spot that difference in the photo?
The earth is really big, compared to us and compared to how far away we can see things on or near the surface. The angles involved are simply too small to be noticeable. We can typically see mountains, etc., no further than about 100 miles away. At that distance, the angle amounts to 1.5 degrees.
Objects do fall below the horizon in the distance but it can often be too small to see.
The first problem for an earth bound observer is that you need a "flat" surface that actually conforms to the earth's shape to see the effect. You can see this effect over the sea, but not over land - it is too irregular and lumpy.
The second problem is that to see that effect you need clear conditions. You have to be able to see like ten plus kilometers for it to be obvious. You can't see this far in hazy parts of the world.
However, the effect is real and well known to sailors and people near the sea. When approaching land, the tops of hills appear first. When a ship approaches land the sails or high parts of the ship are seen first. You can see this yourself if you watch a large ship leave port and disappear over the horizon on clear day! The effect is slow so you may need to watch for an hour or more but it is unmistakeable.
The drop due to curvature of the earth increases (roughly) with the square of distance, so the effect is small close but increase more rapidly with distance. The effect is four times as great at double the distance.
Here are some approximate values of the curvature effect, ie, the loss of height with distance for an observer at sea level.
1 km 10 cm (You would need a very smooth sea plus excellent eyesight or binoculars to see this.)
2 km 41 cm
5 km 2.6 metres
10 km 10.5 metres
20 km 41 metres
40 km 170 metres (You would need an extremely clear day to see this far.)
In practice, variation of temperature with height above the sea make the air less of more dense in layers which bends light and so complicates things. This means that sometimes it is possible to see "over the horizon" and at other times we simply can't see to the geometric horizon. When the sea/air temperature differences are great or there are are multiple layers of warm and cool air we see mirage effects including complex things like land appearing to float above the sea.
OK so Earth is spherical you agree yes?
this is, i think, the best piece of evidence for a spherical earth. you cannot produce a flat model capable of accounting for this phenomenon.
Now that humanity knows quite positively that the Moon is not a piece of cheese or a playful god, the phenomena that accompany it (from its monthly cycles to lunar eclipses) are well-explained. It was quite a mystery to the ancient Greeks, though, and in their quest for knowledge, they came up with a few insightful observations that helped humanity figure out the shape of our planet.
Aristotle (who made quite a lot of observations about the spherical nature of the Earth) noticed that during lunar eclipses (when the Earth’s orbit places it directly between the Sun and the Moon, creating a shadow in the process), the shadow on the Moon’s surface is round. This shadow is the Earth’s, and it’s a great clue on the spherical shape of the Earth.
Since the earth is rotating (see the “Foucault Pendulum” experiment for a definite proof, if you are doubtful), the consistent oval-shadow it produces in each and every lunar eclipse proves that the earth is not only round but spherical – absolutely, utterly, beyond a shadow of a doubt not flat.
Refer to the following image from Wikipedia for more details on what happens during a lunar eclipse:
Click for the Original
(2) Ships and the Horizon
If you’ve been next to a port lately, or just strolled down a beach and stared off vacantly into the horizon, you might have, perhaps, noticed a very interesting phenomenon: approaching ships do not just “appear” out of the horizon (like they should have if the world was flat), but rather emerge from beneath the sea.
But – you say – ships do not submerge and rise up again as they approach our view (except in “Pirates of the Caribbean”, but we are hereby assuming that was a fictitious movie). The reason ships appear as if they “emerge from the waves” is because the world is not flat: it’s round.
Imagine an ant walking along the surface of an orange, into your field of view. If you look at the orange “head on”, you will see the ant’s body slowly rising up from the “horizon”, because of the curvature of the Orange. If you would do that experiment with a long road, the effect would have changed: The ant would have slowly ‘materialized’ into view, depending on how sharp your vision is.
(3) Varying Star Constellations
This observation was originally made by Aristotle (384-322 BCE), who declared the Earth was round judging from the different constellations one sees while moving away from the equator.
After returning from a trip to Egypt, Aristotle noted that “there are stars seen in Egypt and […] Cyprus which are not seen in the northerly regions.” This phenomenon can only be explained with a round surface, and Aristotle continued and claimed that the sphere of the Earth is “of no great size, for otherwise the effect of so slight a change of place would not be quickly apparent.” (De caelo, 298a2-10)
The farther you go from the equator, the farther the ‘known’ constellations go towards the horizon, and are replaced by different stars. This would not have happened if the world was flat:
(4) Shadows and Sticks
If you stick a stick in the [sticky] ground, it will produce a shadow. The shadow moves as time passes (which is the principle for ancient Shadow Clocks). If the world had been flat, then two sticks in different locations would produce the same shadow:
But they don’t. This is because the earth is round, and not flat:
Eratosthenes (276-194 BCE) used this principle to calculate the circumference of the Earth quite accurately. To see this demonstrated, refer to my experiment video about Eratosthenes and the circumference of the earth – “The Earth’s curvature is tasty!“.
(5) Seeing Farther from Higher
Standing in a flat plateau, you look ahead of you towards the horizon. You strain your eyes, then take out your favorite binoculars and stare through them, as far as your eyes (with the help of the binocular lenses) can see.
Then, you climb up the closest tree – the higher the better, just be careful not to drop those binoculars and break their lenses. You then look again, strain your eyes, stare through the binoculars out to the horizon.
The higher up you are the farther you will see. Usually, we tend to relate this to Earthly obstacles, like the fact we have houses or other trees obstructing our vision on the ground, and climbing upwards we have a clear view, but that’s not the true reason. Even if you would have a completely clear plateau with no obstacles between you and the horizon, you would see much farther from greater height than you would on the ground.
This phenomena is caused by the curvature of the Earth as well, and would not happen if the Earth was flat:
(6) Ride a Plane
If you’ve ever taken a trip out of the country, specifically long-destination trips, you could notice two interesting facts about planes and the Earth:
(A picture of the curved horizon from a Concorde plane can be seen here).
- Planes can travel in a relatively straight line a very long time and not fall off any edges. They can also, theoretically (and some do, though with stops along the way), circle the earth.
Correction (Courtesy of Klaynos, from scienceforums.net): Apparently, planes can circle the Earth without stopping!- If you look out the window on a trans-Atlantic flight, you can, most of the times, see the curvature of the earth in the horizon. The best view of the curvature used to be on the Concorde, but that plane’s long gone. I can’t wait seeing the pictures from the new plane by “Virgin Galactic” – the horizon should look absolutely curved, as it actually is from a distance.
(7) Look at Other Planets
The Earth is different from other planets, that much is true. After all, we have life, and we haven’t found any other planets with life (yet). However, there are certain characteristics all planets have, and it will be quite logical to assume that if all planets behave a certain way, or show certain characteristics – specifically if those planets are in different places or were created under different circumstances – our planet is the same.
In other words: If so many planets that were created in different locations and under different circumstances show the same property, it’s likely that our own planet has the same property as well. All of our observations show planets are spherical (and since we know how they’re created, it’s also obvious why they are taking this shape). Unless we have a very good reason to think otherwise (which we don’t), our planet is very likely the same.
In 1610, Galileo Galilei observed the moons of Jupiter rotating around it (click here to see a beautiful video reconstruction of his observations). He described them as small planets orbiting a larger planet – a description (and observation) that was very difficult for the church to accept as it followed a geocentric model where everything was supposed to revolve around the Earth. This observation also showed that the planets (Jupiter, Neptune, and later Venus was observed too) are all spherical, and all orbit the sun.
A flat planet (ours or any other planet) would be such an incredible observation that it would pretty much go against everything we know about how planets form and behave. It would not only change everything we know about planet formation, but also about star formation (as our sun would have to behave quite differently to accustom a “flat earth” theory), what we know of speeds and movements in space (like planets orbits, and the effects of gravity, etc). In short, we don’t just suspect that our planet is spherical. We know it.
(8) The Existence of Timezones
The time in New York, at the moment these words are written, is 12:00pm. The sun is in the middle of the sky (though it’s hard to see with the current cloud coverage). In Beijing, where Michael Phelps is likely getting ready for yet another gold medal, it’s 12:00am, midnight, and the sun is nowhere to be found.
In Adelaide, Australia, it is 1:30am. More than 13 hours ahead. There, the sunset is long gone – so much so, that it’s soon going to rise up again in the beginning of a new day. Here’s a list showing what time it is around the world when it is 12:00pm in New York city.
This can only be explained if the world is round, and rotating around its own axis. At a certain point when the sun is shining on one part of the Earth, the opposite side is dark, and vise versa. That allows for time differences and timezones, specifically ones that are larger than 12 hours.
Another point concerning timezones, the sun and flat/spherical Earth: If the sun was a “spotlight” (very directionally located so that light only shines on a specific location) and the world was flat, we would have seen the sun even if it didn’t shine on top of us (as you can see in the drawing below). The same way you can see the light coming out of a spotlight on a stage in the theater, even though you – the crowd – are in the dark. The only way to create two distinctly separate timezones, where there is complete darkness in one while there’s light in the other, is if the world is spherical.
(9) The Center of Gravity
There’s an interesting fact about mass: it attracts things to it. The force of attraction (gravity) between two objects depends on their mass and the distance between them. Simply said, gravity will pull toward the center of mass of the objects. To find the center of mass, you have to examine the object.
Consider a sphere. Since a sphere has a consistent shape, no matter where on it you stand, you have exactly the same amount of sphere under you. Imagine an ant (perhaps the same one from the previous point) walking around on a crystal ball. Assuming the crystal ball is polished, the ant’s only indication of movement would be the fact it’s moving its feet. The scenery (and shape of the surface) would not change at all.
Consider a flat plane. The center of mass of a flat plane is in its center (more or less – if you want to be more accurate, feel free to do the entire [shriek] integration [shriek] process), and the force of gravity will pull a person toward the middle of the plain. That means that if you stand on the edge of the plane, gravity will be pulling you toward the middle, not straight down like you usually experience.
I am quite positive that even for Australians an apple falls downwards, but if you have your doubts, I urge you to try it out – just make sure it’s nothing that can break or hurt you. Just in case gravity is consistent after all.
Further reading about the center of mass and about distribution of mass can be found here. And if you are brave enough to handle some equations (not involving integration), you can learn some more about Newton’s Law of Universal Gravitation.
(10) Images from Space
In the past 60 years of the space exploration era of humanity’s history, we’ve launched satellites, probes and people to space. Some of them got back, some of them still float through the solar system (and almost beyond it) and transmit amazing images over to our receivers on Earth.
