RS
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July 16th, 2019 at 1:57:46 AM permalink
Assume the bird's wingspan is 5 feet and the picture was taken on July 4'th, 2019. In case it isn't obvious, that big orange circle behind it is the sun.



What if the image was taken on January 3, 2019 and the bird's wingspan is 7 feet?


The picture was taken on Earth.


You don't get any more hints, you have enough information to figure it out.


The question is: How far away is the bird from the camera?
ChesterDog
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July 16th, 2019 at 3:24:23 AM permalink
Quote: RS

...The question is: How far away is the bird from the camera?




1500 feet.


The sun's subtends an angle of 1/2 degree in the sky. The image of the bird is about 0.37 of the sun's image. This makes the bird's wingspan about 0.185 degrees, or about 0.00323 radians (0.185*pi/180.)


Dividing 5 feet by 0.00323 radians gives about 1500 feet.


DRich
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July 16th, 2019 at 7:46:04 AM permalink
RS, I think you are mistaken. The suns diameter is about 430,000 miles. Th bird is about 1/3 the size of the sun; therefore the birds wingspan is about 143,000 miles wide.
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billryan
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July 16th, 2019 at 7:48:47 AM permalink
How do we know that's a bird and not a hole in the sun?
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TigerWu
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July 16th, 2019 at 8:15:38 AM permalink
Depends on the focal length of the camera lens.
Joeman
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July 16th, 2019 at 8:32:24 AM permalink
Quote: RS

The question is: How far away is the bird from the camera?


1,427 ft.

OK, I had to look up that the sun is 94.5 Mil mi form earth at aphelion (July 4) and 91.4 Mil mi at perihelion (the latter to be used for extra credit below), and the diameter of the sun is 860,340 mi.

If the bird's (projected) wingspan were the same as the (projected) diameter of the sun, the answer could be solved by using ratios from similar triangles. That is the ratio of height, h, to wingspan would be the same as the ratio of the sun's distance to its diameter. This works out to be h = 5 x (94,500,000 / 860,340) = 549 ft

However, the bird's wingspan in the picture only stretches to a fraction of the sun diameter. Measuring on my monitor, the bird's wingspan is 75 mm, and the sun diameter is 195 mm. This would yield a ratio of 2.6. So, you would multiply this ratio by 549 ft to get an actual height above the observer of 1,427 ft.


Quote:

What if the image was taken on January 3, 2019 and the bird's wingspan is 7 feet?

Just substitute 91.4 Mil for the distance to the sun and 7 ft for the wingspan and recalculate the equations described above. 1934 ft.
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rawtuff
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July 16th, 2019 at 10:13:33 AM permalink
The earth is flat, so this photo is fake, NASA is lying to you and the water is always flat and level.
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RS
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July 16th, 2019 at 11:09:02 AM permalink
Quote: ChesterDog

1500 feet.


The sun's subtends an angle of 1/2 degree in the sky. The image of the bird is about 0.37 of the sun's image. This makes the bird's wingspan about 0.185 degrees, or about 0.00323 radians (0.185*pi/180.)


Dividing 5 feet by 0.00323 radians gives about 1500 feet.



I would say this is generally correct. However, you can still get a more precise answer by taking into account the time of year it was taken, so I can’t give you credit. Sorry. :(

Quote: DRich

RS, I think you are mistaken. The suns diameter is about 430,000 miles. Th bird is about 1/3 the size of the sun; therefore the birds wingspan is about 143,000 miles wide.


You bring up a valid point, this was my first guess at it too.

Quote: billryan

How do we know that's a bird and not a hole in the sun?


Hmmm. On second thought, this is certainly a possibility.

Quote: TigerWu

Depends on the focal length of the camera lens.


I actually didn’t really consider this and have no idea how camera focal length lenses and stuff work. I would say, uhh, just assume it’s a normal lens? Or whatever gets the answer I came up with.

Quote: Joeman

1,427 ft.

OK, I had to look up that the sun is 94.5 Mil mi form earth at aphelion (July 4) and 91.4 Mil mi at perihelion (the latter to be used for extra credit below), and the diameter of the sun is 860,340 mi.

If the bird's (projected) wingspan were the same as the (projected) diameter of the sun, the answer could be solved by using ratios from similar triangles. That is the ratio of height, h, to wingspan would be the same as the ratio of the sun's distance to its diameter. This works out to be h = 5 x (94,500,000 / 860,340) = 549 ft

However, the bird's wingspan in the picture only stretches to a fraction of the sun diameter. Measuring on my monitor, the bird's wingspan is 75 mm, and the sun diameter is 195 mm. This would yield a ratio of 2.6. So, you would multiply this ratio by 549 ft to get an actual height above the observer of 1,427 ft.


Quote:

What if the image was taken on January 3, 2019 and the bird's wingspan is 7 feet?

Just substitute 91.4 Mil for the distance to the sun and 7 ft for the wingspan and recalculate the equations described above. 1934 ft.


Ding ding ding! This is the way I solved it. I came up with the bird being 2/5’ths or 1/2.5’s of the sun’s diameter since I measured the screen using my thumb, but that’s beside the point. Well done.

Although I think I may have made it easier by offering the extra credit because that in itself is kind of a hint.

Quote: rawtuff

The earth is flat, so this photo is fake, NASA is lying to you and the water is always flat and level.


This is the real answer. It was recently discovered that the “bird” is actually a shadow reflection from our flat earth’s surrounding ice walls. And as we all know, birds aren’t real (google it).


I owe everyone who submitted an answer a beer.


If you’re actively gambling in a casino.


And the casino comps the beer.


Tip not included.
Joeman
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July 16th, 2019 at 11:43:01 AM permalink
Fun Puzzle, RS. BTW, I think you may have already given me my beer when I was at Harrah's New Orleans a couple of weeks ago. Thanks!

Quote: RS

Quote: ChesterDog

1500 feet.


The sun's subtends an angle of 1/2 degree in the sky. The image of the bird is about 0.37 of the sun's image. This makes the bird's wingspan about 0.185 degrees, or about 0.00323 radians (0.185*pi/180.)


Dividing 5 feet by 0.00323 radians gives about 1500 feet.



I would say this is generally correct. However, you can still get a more precise answer by taking into account the time of year it was taken, so I can’t give you credit. Sorry. :(

in C-Dog's defense, I think the error introduced by measuring the bird & sun on your monitor/phone will be greater than any error introduced by approximating the angle spanned by the sun or using the average of 93 Mil mi for the distance to the sun.
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Wizard
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RS
July 16th, 2019 at 2:00:44 PM permalink
Sorry to be late to the party. The answer in large part depends on how exactly the wingspan is defined. It seems there are some outlying feathers, which I'm not sure count.



The ratio of the distance to the sun to the diameter is apx 107.6.

For the bird to completely eclipse the sun, with nothing left over, it would have a wingspan of 5' * (10.25/3.5) = 14.64'.

Based on similar triangles, the distance from the bird is 1.64 * 107.6 = apx 1,575'.

I see other answers are close so I think I'm happy.
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billryan
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July 16th, 2019 at 7:43:19 PM permalink
Birds are miniature dinosaurs. Dinosaur bones were created by Satan in an attempt to convince people the earth is older than 6,000 years.
Chickens are birds. Mind blown.
The difference between fiction and reality is that fiction is supposed to make sense.
Ayecarumba
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July 16th, 2019 at 9:27:22 PM permalink
Quote: billryan

Birds are miniature dinosaurs. Dinosaur bones were created by Satan in an attempt to convince people the earth is older than 6,000 years.
Chickens are birds. Mind blown.



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