Curvature of the Earth

Hello

Just joined your forum a few years of following.

I'm a little troubled though from October's news of the skydiver Felix Baumgartner's jump from the edge of the atmolayer.  Why did the horizon seem to curve and why didn't he fall at a constant rate given UA? 

The curvature you saw was a combination of lens distortion and seeing the edge if the sun's spotlight (something we would expect to be curved).

The reason that the skydiver "fell" at 32 feet / second squared is because the earth was accelerating up towards the diver at 32 feet / second squared.

but if the earth is accelerating upwards wouldn't we eventually reach and surpass the speed of light

Not according to physics. It states that we can accelerate forever and never reach "c". Someone who understands it better will be along shortly to link or cite something for you if you haven't already looked up the information for yourself.

A constantly accelerating object would never actually reach c because of time dilation / Lorentz contraction.  It's kinetic energy would increase arithmetically, but it's velocity would approach c asymptotically.   An observer on the accelerating object would think they were travelling faster than light, because their clock would be running slow.

However, what UA completely fails to account for is the local variation in g from place to place.  It's 0.5% more at the poles than at the poles & drops off according to an inverse square law with altitude.

It also raises the question of what we are accelerating through, and how utterly empty it must be for us not to be fried by ultra-high energy photons & atoms of gas.

Basically mate - it's bobbins

The curvature you saw was a combination of lens distortion and seeing the edge if the sun's spotlight (something we would expect to be curved).

The reason that the skydiver "fell" at 32 feet / second squared is because the earth was accelerating up towards the diver at 32 feet / second squared.

Lens distortion? But I saw this on the tv?

Quote from: Pongo on December 07, 2012, 09:59:27 PM

The curvature you saw was a combination of lens distortion and seeing the edge if the sun's spotlight (something we would expect to be curved).

The reason that the skydiver "fell" at 32 feet / second squared is because the earth was accelerating up towards the diver at 32 feet / second squared.

Lens distortion? But I saw this on the tv?

you are still looking through the camera in which it was filmed

You saw something like this, right?  The lens distorted the horizon.  It is a wide angle lens.

A constantly accelerating object would never actually reach c because of time dilation / Lorentz contraction.  It's kinetic energy would increase arithmetically, but it's velocity would approach c asymptotically.   An observer on the accelerating object would think they were travelling faster than light, because their clock would be running slow.

However, what UA completely fails to account for is the local variation in g from place to place.  It's 0.5% more at the poles than at the poles & drops off according to an inverse square law with altitude.

It also raises the question of what we are accelerating through, and how utterly empty it must be for us not to be fried by ultra-high energy photons & atoms of gas.

Basically mate - it's bobbins

Incorrect. AWT accounts for gravitational differences perfectly.

As for what we're accelerating into, I think that's about the same as the question of what the Universe is expanding into, to which the answer is a very complicated way of saying nothing.

We're protected from any random space particles by the AWW.

I thought the UA was fixed at 9.8 m/sec? not moving faster.
Maybe instead of UA we can have UC? Universal Constant

I thought the UA was fixed at 9.8 m/sec²? not moving faster.

Fixed, because you thought wrong.

Quote from: Youngmeister on December 11, 2012, 05:18:59 PM

Quote from: Pongo on December 07, 2012, 09:59:27 PM

The curvature you saw was a combination of lens distortion and seeing the edge if the sun's spotlight (something we would expect to be curved).

The reason that the skydiver "fell" at 32 feet / second squared is because the earth was accelerating up towards the diver at 32 feet / second squared.

Lens distortion? But I saw this on the tv?

you are still looking through the camera in which it was filmed

But why would Red Bull (who financed this whole test) use different lenses on the module's outboard camera?  It seemed normal until around 60,000 ft?

Quote from: canucks#01fan on December 11, 2012, 10:09:52 PM

Quote from: Youngmeister on December 11, 2012, 05:18:59 PM

Quote from: Pongo on December 07, 2012, 09:59:27 PM

The curvature you saw was a combination of lens distortion and seeing the edge if the sun's spotlight (something we would expect to be curved).

The reason that the skydiver "fell" at 32 feet / second squared is because the earth was accelerating up towards the diver at 32 feet / second squared.

Lens distortion? But I saw this on the tv?

you are still looking through the camera in which it was filmed

But why would Red Bull (who financed this whole test) use different lenses on the module's outboard camera?  It seemed normal until around 60,000 ft?

almost all camera lenses are wide-angled. You can see more, and people want that.

The whole thing was a promotional stunt. They played up the "space jump" with many mindless journalists repeating it. There was a graphic of a spinning globe spinning silently behind the shots as the backdrop. It was pure hype. The wide-angle lenses just reinforced the "space jump" idea and gave it added drama. It was a giant Red Bull advert and they got a slew of free airtime.

The whole thing was a promotional stunt. They played up the "space jump" with many mindless journalists repeating it. There was a graphic of a spinning globe spinning silently behind the shots as the backdrop. It was pure hype. The wide-angle lenses just reinforced the "space jump" idea and gave it added drama. It was a giant Red Bull advert and they got a slew of free airtime.

You're saying the jump was never made?

The jump was made.

The apparent curvature is a combination of effects.

1. Optical illusion.  An expansive horizon appears to curve to our eyes.  Even in RET, a commercial aircraft never reaches an altitude to allow you to perceive a spherical earth's curvature - yet people claim to see this all the time.  Our eyes play tricks on us.

2.  Wide-angle lens.  As above, this enhances the effect.  The image is a little distorted even at lower altitudes.

3.  At very high altitudes, looking out along the edge of a disc will produce - you guessed it - a curve.

I don't think Red Bull intentionally swapped lenses or faked any of this.  I believe the flight and jump were genuine - but it didn't get high enough to perceive the true nature of the earth as a disc.  Sub-orbital flights are not only possible, but rather routine, and they do reveal a breathtaking view of our earth, but not a global panorama - even if it were a sphere.

Quote from: Ski on December 12, 2012, 07:28:07 PM

The whole thing was a promotional stunt. They played up the "space jump" with many mindless journalists repeating it. There was a graphic of a spinning globe spinning silently behind the shots as the backdrop. It was pure hype. The wide-angle lenses just reinforced the "space jump" idea and gave it added drama. It was a giant Red Bull advert and they got a slew of free airtime.

You're saying the jump was never made?

  No. They had a graphic in the back of the live feed (as in behind several other open video 'windows' that was clearly a fake revolving "earth" to emphasize the whole outlandishness of the affair. If you see the live feed, I'm sure you'll see what I mean. He went up in a big balloon and jumped out.