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Sitnalta
2008-Feb-07, 07:54 PM
I've been sort of racking my brain on a little thought experiment lately. It came about after somebody asked me how much they'd weigh on a neutron star. The answer (for an average 200-lb person here on Earth) was in the order of 260 billion pounds.

Then I thought... "what if you could stand on a neutron star?" What conditions would have to exist? Now, put aside the insane heat, radiation and magnetic fields that would obliterate you from thousands of miles away, if the star was spinning fast enough, you could be chillin' at the equator, and you might even have your own oxygenated atmosphere to breathe if your luck holds out.

As far as I can tell, the fastest neutron star observed spins at 1,122 times every second. Not bad for an object several miles in diameter. But even with centripetal force counteracting gravity, you'd still be a billion pounds too heavy. But I didn't take into account relativity. Which is a bit beyond a film major such as myself (I got a C- in physics and was happy for it.) I figure since extreme speed and/or gravity causes time to tick slower relative to us, the star might be spinning much, much faster in its own little bubble of space time than we can observe. Unless that phenomenon is already corrected for when discovering a new neutron star.

So the question is: Taken into account relativity and centripetal force, is it physically possible for a neutron star to have a gravitational "safe zone" along its equator?

Ok, I know the answer is "NO, YOU WOULD DIE", but it's still fun to think about.

Bozola
2008-Feb-07, 10:30 PM
You'd have to be a complete degenerate.

antoniseb
2008-Feb-07, 11:24 PM
Let's imagine that your body (minus your head) was a weightless cylinder with a 15 cm radius, and the strength of Tungsten. This 1.7 meter long cylinder is placed vertically on a very firm surface. The we place your head on it, and your head weighs lets say 30 billion tons. As you might guess, the Tungsten would rapidly get spread out into a layer one atomic nucleus thick.

But you're asking wither it might not be possible for a rapidly enough spinning neutron star to have a place where centripetal acceleration, and relativistic factors might almost equal the gravitational acceleration. I think the answer to this is "not for long". You could contrive a situation in which a neutron star that is already spinning close to the stable limit merges with another neutron star in such a way as to add the maximum angular momentum. If that were to happen, then for perhaps some microseconds the situation you're asking about might exist before the energy lost through gravitational waves and other relativistic details slowed it down enough that your weight would crush you.

Let me add that if the spinning did get fast enough to come close to balancing gravity, the forces that degenerate the atoms would also be overcome, and so the equator of the neutron star would explode.

Noclevername
2008-Feb-08, 02:07 AM
You'd have to be a complete degenerate.

Groan! I collapsed when I read that joke.

3.885AM
2008-Feb-08, 03:59 AM
Setting aside the problems mentioned above, if you could stand on the surface, what would you see looking out at the horizon.? Specifically, what would the surface look like, and how would the stars near the horizon be distorted?

Ilya
2008-Feb-08, 04:07 AM
Groan! I collapsed when I read that joke.

If that was a deliberate pun, you have a crushing sense of humor.

ravens_cry
2008-Feb-08, 04:31 AM
I feel neutral about it.

Sitnalta
2008-Feb-08, 04:42 AM
Setting aside the problems mentioned above, if you could stand on the surface, what would you see looking out at the horizon.? Specifically, what would the surface look like, and how would the stars near the horizon be distorted?

I'd imagine it'd be an almost perfect mirror surface, and the sky would be flickering streaks of light. Might be pretty trippy actually.

As for the neutron star puns, they give me a pulsing headache.

Celestial Mechanic
2008-Feb-08, 04:57 AM
When you stand on a neutron star,
You won't know how flat you are.

:D

Tim Thompson
2008-Feb-08, 05:37 AM
Standing up on a neutron star is one of the key elements in Robert Forward (http://www.robertforward.com/)'s excellent science fiction novel Dragon's Egg (http://www.amazon.com/Dragons-Egg-Del-Rey-Impact/dp/034543529X/ref=sr_1_1?ie=UTF8&s=books&qid=1202448192&sr=1-1), first published in 1981. The story centers on life forms on the surface of a neutron star, and how they deal both with the extreme gravity, and the extreme magnetic fields. Forward was a physicist, and did an excellent job describing an environment consistent with the physics of neutron stars. One of the key elements was the "hard direction" vs the "easy direction", when the neutron star creatures tried to move across (hard) or along (easy) magnetic field lines.

Noclevername
2008-Feb-08, 06:07 AM
If that was a deliberate pun, you have a crushing sense of humor.

No, I just realize the gravity of the situation.

Ilya
2008-Feb-08, 01:26 PM
Read last few pages of Alastair Reynolds' "Revelation Space", where a character is standing on the surface of a neutron star. She is kept alive and unharmed by local manipulation of gravity, not by spin, but since Reynolds is an astrophysicist I trust the "landscape" description to be accurate.

punkrockbong151
2008-Feb-09, 01:05 AM
ok, with or without all the luck you could happen to obtain with this neutron star situation, your skeleton couldn't hold up to that kind of pressure.

i think anybody who has watched dragonball Z, when goku was flying to namek in bulma's dad's space ship and turned on the gravity to train while he waited to get there would know this (turned it to like 1000x I think and made a comment about his skeletal structure crushing if it was any higher)

punkrockbong151
2008-Feb-09, 01:08 AM
No, I just realize the gravity of the situation.

i was practically laying flattened to the floor laughing when i read these

transreality
2008-Feb-09, 01:57 AM
humor is a bit thin on the ground around here.

Celestial Mechanic
2008-Feb-09, 05:00 AM
humor is a bit thin on the ground around here.
As is pretty much anything else on the surface of a neutron star! :D

Noclevername
2008-Feb-09, 04:20 PM
I'm sorry for starting this punning, I was just being dense. I'd be crushed if you didn't care for it.

mantiss
2008-Feb-09, 08:57 PM
Well all the atoms in your body would be deformed into elongated spikes, making it a thorny situation at best.

Also with an atmosphere of vaporized iron 1 cm thick, it leaves very little breathing room.

Noclevername
2008-Feb-09, 09:03 PM
I hope my puns don't fall flat.

Bozola
2008-Feb-10, 12:43 AM
While they are an attractive place to visit, I've heard that the services and amenities are spread thin on the ground.

Noclevername
2008-Feb-10, 12:57 AM
These puns have got me fit to be tide! My pulsar racing at the thought.

Bozola
2008-Feb-10, 01:24 AM
Of the matter at hand, I always thought that Arthur C. Clarke's feghoot (http://www.awpi.com/Combs/Shaggy/557.html) was the final word.

Noclevername
2008-Feb-10, 02:53 AM
Of the matter at hand, I always thought that Arthur C. Clarke's feghoot (http://www.awpi.com/Combs/Shaggy/557.html) was the final word.

...I bow before the Master. :lol::lol::lol:

trinitree88
2008-Feb-10, 08:16 PM
I've been sort of racking my brain on a little thought experiment lately. It came about after somebody asked me how much they'd weigh on a neutron star. The answer (for an average 200-lb person here on Earth) was in the order of 260 billion pounds.

Then I thought... "what if you could stand on a neutron star?" What conditions would have to exist? Now, put aside the insane heat, radiation and magnetic fields that would obliterate you from thousands of miles away, if the star was spinning fast enough, you could be chillin' at the equator, and you might even have your own oxygenated atmosphere to breathe if your luck holds out.

As far as I can tell, the fastest neutron star observed spins at 1,122 times every second. Not bad for an object several miles in diameter. But even with centripetal force counteracting gravity, you'd still be a billion pounds too heavy. But I didn't take into account relativity. Which is a bit beyond a film major such as myself (I got a C- in physics and was happy for it.) I figure since extreme speed and/or gravity causes time to tick slower relative to us, the star might be spinning much, much faster in its own little bubble of space time than we can observe. Unless that phenomenon is already corrected for when discovering a new neutron star.

So the question is: Taken into account relativity and centripetal force, is it physically possible for a neutron star to have a gravitational "safe zone" along its equator?

Ok, I know the answer is "NO, YOU WOULD DIE", but it's still fun to think about.

Only if you were supernatural. Then the trick would be to create a tunnel beneath your slightly smaller in surface area than your feet, going all the way through the neutron star, like a removed core in an apple. (You need to suspend all the forces interacting to collapse the tunnel....but remember, you are supernatural here)....then from a distant orbit, safely above the Roche lobe, you need to construct a neutrino laser...a "naser", in your starship Enterprise and beam it's collimated effects..(two more supernaturals here)...towards the tunnel. Offsetting the twin neutrino gradient/gravitational field of the neutron star, and acting not only on your feet, but throughout your body to mitigate the star's tidal disruptions...you'll be fine. Radiation?..one more supernatural. But, if real Vulcans arrive in orbit, and zap
the Enterprise's naser......it's one more science experiment gone bad,.....and under the bleachers Fermi thought the natives were friendly in the New World. pete

Jay200MPH
2008-Feb-11, 02:14 PM
I actually worked out the numbers in Matlab ages ago for exactly this problem. I forget the spin rate I used for the star but the "comfort zones" (between 0.5g and 3g) ended up being on the order of micrometers wide in either hemisphere. Closer to the equator and you're flung out into space; closer to the poles and it's pancake-town. How thin can you suck in your gut?

- J

dhd40
2008-Feb-11, 02:32 PM
(snip)

Ok, I know the answer is "NO, YOU WOULD DIE", but it's still fun to think about.

Yes, itīs fun. And the funny thing is, Atlantis could be found there? :)

Celestial Mechanic
2008-Feb-11, 04:12 PM
Yes, itīs fun. And the funny thing is, Atlantis could be found there? :)
I guess you too have noticed that Sitnalta is Atlantis spelled backwards. :)

Tensor
2008-Feb-11, 04:42 PM
Seems everyone while worried about the how flat someone would be forgot about the tidal effects on the body standing up. Here (http://www.bautforum.com/questions-answers/42446-neutron-tides.html) is a thread that talks about it. Hmmmm, notice that that thread also wander off into puns.

dhd40
2008-Feb-11, 09:41 PM
I guess you too have noticed that Sitnalta is Atlantis spelled backwards. :)

:):):)