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The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

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Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#41

Post by lifeisstillgood »

einrealist wrote: post #20
lifeisstillgood wrote: post #12

Earlier quoted context omitted.

I could not take my eyes off "One Birth" / "One Death" Fascinating - and I think humanity is "winning"

It makes me sad because most of the births are in underdeveloped countries, where people have no access to clean water and healthy food. And as more people of countries like China enter middle class, the resources we depend on, will diminish faster and faster.

Please watch anything by Hans Rosling for an entertaining and educational counter-balance to your fears, ; while having some validity, over population is it one of humanities most pressing problems.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#42

Post by bch »

darklajid wrote: post #14
lifeisstillgood wrote: post #12

Earlier quoted context omitted.

I could not take my eyes off "One Birth" / "One Death" Fascinating - and I think humanity is "winning"

Second kid since yesterday. Fighting for humanity here.. ;-)

At that rate, better stock up on diapers.

http://xkcd.com/605/

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#43

Post by [deleted] »

ubercow13 wrote: post #38
deletes wrote: post #37

Earlier quoted context omitted.

Spacetime in the center of a perfect spherical object is the same as a point in empty space, you can't tell them apart. Of course that only counts for the exact point in the center. So the time will not tick slower there as to someone far from any objects.

What? The lowest potential in a uniform sphere is at the centre not the surface ( http://en.wikipedia.org/wiki/File:GravityPotential.jpg ). Also graviational time dilation depends on the potential not the force (curvature) so it is irrelevant if the point at the centre is shifted in spacetime

[deleted]

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#44

Post by doorhammer »

joezydeco wrote: post #2

Lemme guess, you caught this from http://xkcd.com/1331/ too?

I stared at the 'my turn signal' and 'car in front of me' signal together for way too long. I went into the same trance I do sitting behind cars at a real red light.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#46

Post by joezydeco »

doorhammer wrote: post #44
joezydeco wrote: post #2

Lemme guess, you caught this from http://xkcd.com/1331/ too?

I stared at the 'my turn signal' and 'car in front of me' signal together for way too long. I went into the same trance I do sitting behind cars at a real red light.

I caught that too! That was a bit of icing on a really clever cartoon.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#47

Post by [deleted] »

ubercow13 wrote: post #38
deletes wrote: post #37

Earlier quoted context omitted.

Spacetime in the center of a perfect spherical object is the same as a point in empty space, you can't tell them apart. Of course that only counts for the exact point in the center. So the time will not tick slower there as to someone far from any objects.

What? The lowest potential in a uniform sphere is at the centre not the surface ( http://en.wikipedia.org/wiki/File:GravityPotential.jpg ). Also graviational time dilation depends on the potential not the force (curvature) so it is irrelevant if the point at the centre is shifted in spacetime

[deleted]

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#48

Post by wellboy »

hackaflocka wrote: post #45

Why do planets, stars and moons spin? Are there any that don't?

My armchair attempt would say that a star/moon would only NOT spin if at their creation, the clouds of material came 100% from all sides equally.

Normally though, stars or planets are caught from clouds catching and revolving around each other for a couple of million years until the condense to a solid object. Thus the spin.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#49

Post by stcredzero »

raverbashing wrote: post #26
ars wrote: post #7

Anyone feel like calculating the energy embodied in just the rotation of this star?

Makes me wonder if there will be someday an electrical generator using the rotational energy of a celestial body. (this would need to have a reference in the main star, otherwise it would just spin with the planet)

generator using the rotational energy...would need to have a reference in the main star

Nope. You could launch generator pods in a hyperbolic trajectory that would start out escaping the neutron star, but generate electricity from the rotating magnetic field in such a way that it's captured in orbit and comes back to its launch point.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#50

Post by ubercow13 »

ubercow13 wrote: post #38
deletes wrote: post #37

Earlier quoted context omitted.

Spacetime in the center of a perfect spherical object is the same as a point in empty space, you can't tell them apart. Of course that only counts for the exact point in the center. So the time will not tick slower there as to someone far from any objects.

What? The lowest potential in a uniform sphere is at the centre not the surface ( http://en.wikipedia.org/wiki/File:GravityPotential.jpg ). Also graviational time dilation depends on the potential not the force (curvature) so it is irrelevant if the point at the centre is shifted in spacetime

Time will still tick slower though regardless of the first part of what you say being right
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