Show us your animated GIFs... [Volume 4]
Discussion
Gorf said:
Moonhawk said:
As for the moon/earth size. It looks about right to me. The moon is around 27% the size of the earth - and looking at the animation, it looks like the disc of moon would fit just over three times across the face of the earth.
That's not how it works. Their apparent relative size all depends on the field of view and distance from the moon. For example, there is a point somewhere nearer to the Moon (than the probe's position when it took those shots) that the Moon would have a similar apparent size to the Earth and occlude it from view altogether. There's no easy way to get an accurate single image that shows their relative size because the Earth will always be about a quarter of a million miles further from the camera. You'd have to position the camera perpendicular to the orbital radius at its mid point and have a wide enough field of view to cover the 225,000 to 248,000 miles between them into the picture.My linked .gif was obtained from the EPIC camera aboard the Deep Space Climate Observatory, which is stationed close to the L1 Earth-Sun Lagrange point, which is ~1 million miles away from the Earth's sunlit side, and the Moon is about 240,000 miles (variable) from the Earth. My .gif shows the Moon as about 0.34x the width of the Earth, compared to 0.27x in reality. Not too much difference.
The .gif is represented as true-colour, as it would look to our eyes. Yes, you wouldn't be seeing the surrounding stars that easily when looking at a correctly exposed Full Earth
cathalferris said:
Though, Moonhawk isn't too far off the mark. Technically Gorf is correct, but from far enough away (and space is a very big place) the difference in apparent size becomes small compared to the difference in real size.
So big that representations of warp drive have always bothered me. It seems to me that it wouldn't matter how fast you were going, stars passed at warp speed would appear fewer and further between than the popular image.
As you were.
DickyC said:
So big that representations of warp drive have always bothered me. It seems to me that it wouldn't matter how fast you were going, stars passed at warp speed would appear fewer and further between than the popular image.
As you were.
That's not the original photograph. It's been photoshopped to add drama.As you were.
marshalla said:
qube_TA said:
why does it matter, who's on a mobile with capped data?
FTFY.Maybe if you're on roaming data plan and on holiday in the US it would be an issue, but then you'd not be looking at a gif thread.
(or at least wouldn't be clicking the .gifv links)
qube_TA said:
marshalla said:
qube_TA said:
why does it matter, who's on a mobile with capped data?
FTFY.Maybe if you're on roaming data plan and on holiday in the US it would be an issue, but then you'd not be looking at a gif thread.
(or at least wouldn't be clicking the .gifv links)
shakotan said:
qube_TA said:
marshalla said:
qube_TA said:
why does it matter, who's on a mobile with capped data?
FTFY.Maybe if you're on roaming data plan and on holiday in the US it would be an issue, but then you'd not be looking at a gif thread.
(or at least wouldn't be clicking the .gifv links)
But perhaps but if that was an issue why would you be clicking on links that would chew up your mobile data limits?
Although that reminds me of my wife who decided to install iOS8 on her phone when on holiday using 3G. Would have been cheaper to have bought a new phone!
cathalferris said:
Gorf said:
Moonhawk said:
As for the moon/earth size. It looks about right to me. The moon is around 27% the size of the earth - and looking at the animation, it looks like the disc of moon would fit just over three times across the face of the earth.
That's not how it works. Their apparent relative size all depends on the field of view and distance from the moon. For example, there is a point somewhere nearer to the Moon (than the probe's position when it took those shots) that the Moon would have a similar apparent size to the Earth and occlude it from view altogether. There's no easy way to get an accurate single image that shows their relative size because the Earth will always be about a quarter of a million miles further from the camera. You'd have to position the camera perpendicular to the orbital radius at its mid point and have a wide enough field of view to cover the 225,000 to 248,000 miles between them into the picture.My linked .gif was obtained from the EPIC camera aboard the Deep Space Climate Observatory, which is stationed close to the L1 Earth-Sun Lagrange point, which is ~1 million miles away from the Earth's sunlit side, and the Moon is about 240,000 miles (variable) from the Earth. My .gif shows the Moon as about 0.34x the width of the Earth, compared to 0.27x in reality. Not too much difference.
The .gif is represented as true-colour, as it would look to our eyes. Yes, you wouldn't be seeing the surrounding stars that easily when looking at a correctly exposed Full Earth
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