54 votes
Accepted

Does gravity increase the closer to the core you get?

The below figure, taken from Wikipedia shows a model of the free fall acceleration, i.e., 'gravity'. The left-most point corresponds to the center of the Earth; then further right at $6.3\cdot1000$ km ...
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  • 1,959
40 votes
Accepted

How high must one be for the curvature of the earth to be visible to the eye?

Depends on your eye. You can realise the curvature of the Earth by just going to the beach. Last summer I was on a scientific cruise in the Mediterranean. I took two pictures of a distant boat, within ...
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  • 1,663
35 votes

Comparing the Earth with a basketball?

The picture above is an image of the Earth without water. We know that the picture above is a very exaggerated one. About the image The image shown in the question is very widely claimed to show an ...
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23 votes

How high must one be for the curvature of the earth to be visible to the eye?

A quick Google turned up a published article answering precisely this question (Lynch, 2008). The abstract states: Reports and photographs claiming that visual observers can detect the curvature of ...
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  • 5,380
18 votes
Accepted

How to quickly or easily prove the world is spherical?

To answer my own question based on the useful comments here, my favorite methods were: The earth's shadow cast on the moon during an eclipse. It is easy to observe and the flat earth counter argument ...
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  • 361
18 votes

How to quickly or easily prove the world is spherical?

I'm sorry that this answer will be unsatisfactory and, strictly spoken, off topic, but I want to give it anyway. The answer is: You can't. Don't waste your time. Your relative has developed a ...
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17 votes
Accepted

What are we seeing when we see the curvature of Earth?

the horizon is a circle centered at the viewer's position There are two things wrong with this. The first is the assumption that the Earth is entirely spherical - there are no hills, mountains or ...
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16 votes
Accepted

Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?

The sun is really far away. Thus its rays are essentially parallel at the earth's orbit. So, while the diagram you posted is clearly a bit off in terms of the relative size and distance between the ...
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  • 10.7k
14 votes

Effects of CERN on earth's magnetic field?

CERN is a scientific site developed to create anti matter The scientific activity at CERN involves many things, anti matter being just one of them. For more information you can read their anti matter ...
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12 votes

Is Earth an organism?

[I am going to preface this by saying that I am not in one camp or the other in this discussion, as I think there are pros and cons to each side] This links to the "Gaia Theory" proposed by James ...
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  • 171
12 votes
Accepted

Can I see curvature of the Earth on a picture

Make your own numbers... I will take one sample, just change your figures. I have one 4K resolution dron camera. So I can register 3840 x 2160 pixels in one shot. Considering the Earth as an ...
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12 votes
Accepted

Why does this shoreline change this way?

Short version; the beach moves because the waves change. Long version; Beaches, and in fact entire bays, conform in shape and alignment to the prevailing wave patterns in the area. The exact magnitude ...
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  • 4,227
11 votes

Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?

The sun is about 100 times the size of the Earth (in diameter), and the distance from the sun to Earth is about 100 times the diameter of the sun. Below is an image showing the sun, Earth, and the ...
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  • 1,167
11 votes
Accepted

What is this narrow band of clouds?

Given the weather patterns, it looks like Google Earth is generating those cloud overlays from some recent (i.e., the current day) satellite images. That line is suspiciously close to the edge of ...
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  • 3,133
10 votes

How to quickly or easily prove the world is spherical?

Skype. Skype someone at least 10 time zones away. Ask them to point the camera at the sky. Proven. This actually works really well for a psychological reason as well. Its easy to deny abstract ...
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10 votes
Accepted

Volcano in ocean?

From a list & map of known seamounts and submarine volcanoes it is unlikely the orange region in your picture is a submarine volcano. The average depth of the Pacific Ocean is 4280 m. At such a ...
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  • 20.4k
10 votes

Effects of CERN on earth's magnetic field?

In addition to @Michael's excellent answer, keep in mind that fields from charges drop off with the inverse of the distance squared and from dipoles (like those of the Earth and a lot of CERN's larger ...
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  • 331
10 votes
Accepted

How is global greenhouse gas emission calculated?

Your question is simple enough, but the answer depends on what exactly you're looking for. Who is emitting where right now? Real-time global monitoring of greenhouse gas emissions with a high ...
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  • 11.1k
9 votes

At what latitudes does daytime last exactly 24 hours once in the year?

The latitudes today are 66°33′46.1″ N and S, the Arctic and Antarctic Circles. By definition, north of the Arctic circle, and south of the Antarctic circle, everywhere gets at least one day with no ...
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  • 10.7k
9 votes

What are these Gizmos at Izaña Atmospheric Research Center in Spain?

Those are Sun/Moon multispectral photometers and ski radiometers. These are instruments that can scan the sky or track the Sun/Moon for direct measurements. They measure light intensity at multiple ...
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9 votes

How is global greenhouse gas emission calculated?

I can imagine a satellite observation-based model that calculates emissions on a spatial basis but I am not sure if our technology is advanced enough to do that accurately. It is. The first ...
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8 votes

How to measure the cycles of earth moving/rotation?

In theory, if the Earth was a solid object, the Chandler wobble would be easy to understand. It's simply a result of the polhode rolling without slipping on the herpolhode lying in the invariable ...
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8 votes
Accepted

Why is this "independently reproducible proof of non-curvature" wrong?

The biggest flaw I see in a cursory look at this work is failure to compensate for atmospheric refraction. Density varies in the atmosphere enough that the refractive index varies. At low angles ...
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  • 13.9k
8 votes

How high must one be for the curvature of the earth to be visible to the eye?

Further to DrGC's excellent answer, a subjective assessment of visibility of the Earth's curvature can be gleaned from pilot's experioence over many decades. These can be summarized as: Commercial ...
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8 votes

What time and date is the sun directly overhead a given place on Earth?

Having the sun directly overhead can happen only between the Cancer and Capricorn tropics. That is, only the places between 23.5° of latitude north and 23.5° of latitude south. On the Cancer tropic (...
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7 votes

Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?

But if you scale up the Sun to it's real size compared to the Earth, Is pretty big. But then to be realistic in that manner you would also have to scale up the distance from the earth to the sun. ...
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  • 171
7 votes
Accepted

How to locally identify a cold front passage?

A cold front lies in a trough of low pressure and separates air masses. As you mention in your question there are differences in temperature and the winds on either side of the front, though these ...
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  • 13.9k

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