Just Randomness.....

[Julian Alexander]

So im bored and want the smart people here to work thier little brains....or maybe....actually i just want them to work, hehe. So anyways i will be making two hypothetical (hope thats how you spell it) in this post.

 

Okay on with the first one: In the immortal words of my HS Chemistry teacher, In this Universe there is a finite source/amount of energy. Hence forth the same energy that existed before exists now and we are made out of it. In my belief i trust the laws that energy or matter can not be created or destroyed, only "converted" into on form into another (Big No No saying we can create or destroy). I also believe in the future we will be able to convert matter into energy or energy into matter more efficiantly (again i think i spelled that wrong) but as of right now our understanding of the basics is too limited.

 

So off to the second one, which is more of a question to out resident physicists (coughSNOWYcough) or maybe James will answer, but who knows.....Anyways, what im having issues is with some movies showing the destruction of a planet. Most movies just show a planet being blown into rubble and such. But after watching some "educational" shows (Yes i actually watch those because sometimes there is nothing good on the telly). So my belief is that when a planet is being "blown up" (using that term lightly), it would ecentually (hope thats a word) super heat the crust back into a molten slag (eventually pressure would build up) and then an explosion will hence result, some debri will be thrown out to space and some will stay around the old planetary field area. The core of the planet would then be smaller thats it predessecor, which then would start to pull back (i would say gravitational and electromagnetic force) in the derbri field around it to create a new world (albeit smaller than the previous on)....

 

Ahem, Snowy you have the right to spank me if i got stuff wrong ......(oh dont go all too scientific, hehe)

 

So yeah....

 

*Looks around nervously before stepping down the podium*

 

Jules

[Graeme]

I'd love to answer if I can work out what the question is....

 

As I understand orbital mechanics, your basic idea is correct -- if a planet is blown up in such a way that the majority of its material components stay in the same general vicinity, then, subject to outside influences, they will eventually collapse back into a planetary form (albeit, smaller due to the loss of any material that was ejected with sufficient force to preclude later gravitational capture).

 

However, it depends on the method of explosion. The use of some sort of antigravitational device could result in the majority of material escaping the local area. Similarly, an antimatter device would result in the conversion of matter to energy and hence be unable to form a new planetary body. Also, if the initial explosion is sufficiently powerful, there may not be enough matter left in the area to form the nucleus of a new planet.

 

Finally, the gravitational influence of nearby objects may prevent the formation of a new planet. This is one of the theories for the asteriod belt (Jupiters gravitational influence prevented the formation of a planet in that area).

 

Of course, I could be completely wrong with all of this. I haven't had much experience with blowing up planets recently....

[Kurt]

How... random... this is way beyond me...

 

Kurt

[C James]

Okay on with the first one: In the immortal words of my HS Chemistry teacher, In this Universe there is a finite source/amount of energy. Hence forth the same energy that existed before exists now and we are made out of it. In my belief i trust the laws that energy or matter can not be created or destroyed, only "converted" into on form into another (Big No No saying we can create or destroy). I also believe in the future we will be able to convert matter into energy or energy into matter more efficiently (again i think i spelled that wrong) but as of right now our understanding of the basics is too limited.

 

I'll take a crack at this, though I'm exceedingly rusty.

 

Energy and matter can be thought of as just different aspects of the same thing. Einstein's formula (E=MC^2) gives us a formula for this, but it's not as simple as it appears. In general relativity Mass

can vary depending on velocity, so you have relativistic mass. Invariant mass is different; It is the actual mass of an object at rest relative to the observer. In Physics invariant mass is almost always used when speaking of mass, and Einstein used Invariant mass. However, prepare for a headache: E=MC^2 is only generally true *IF* the M is relativistic mass (which Einstein almost never used.)

 

In any case,

Under current theory, matter and energy are just different phases of the same thing. Currently we can convert matter into energy (nuclear weapons and nuclear reactors do this) but we can also created matter from energy in certain reactions observed in particle accelerators. Another form of the conversion of energy into matter is seen in nature, in the cores of very large stars: all Fusion reactions of elements heavier than Iron are a net energy negative: they require more energy than the produce. They absorb energy, and as energy cannot be destroyed, the energy is being converted to mass.

 

This (energy converting to matter) occurs at a very minute scale in some chemical reactions (endothermic ones) where the reaction lowers temperature.

 

So off to the second one, which is more of a question to out resident physicists (coughSNOWYcough) or maybe James will answer, but who knows.....Anyways, what im having issues is with some movies showing the destruction of a planet. Most movies just show a planet being blown into rubble and such. But after watching some "educational" shows (Yes i actually watch those because sometimes there is nothing good on the telly). So my belief is that when a planet is being "blown up" (using that term lightly), it would ecentually (hope thats a word) super heat the crust back into a molten slag (eventually pressure would build up) and then an explosion will hence result, some debri will be thrown out to space and some will stay around the old planetary field area. The core of the planet would then be smaller thats it predessecor, which then would start to pull back (i would say gravitational and electromagnetic force) in the derbri field around it to create a new world (albeit smaller than the previous on)....

 

Basically, it all depends on the energy level of whatever "blows up" the planet. Regardless of its cause, a sufficiently large energy release will be sufficient to shatter a planet and also accelerate the remains beyond escape velocity (which is determined the the planet's mass. For earth, it is about 25,000 mph) With that much velocity, the pieces will not be drawn back by gravity. One cause could be an impact by a large object (such as a small moon) traveling at high velocity. If the impact is not large enough to accelerate the majority of the planet's mass past its escape velocity, then indeed most of it will fall back and re-form.

 

One example of this is the probable source of Saturn's rings. It is theorized that a large comet or asteroid impacted a large icy moon of Saturn, shattering it, and that the debris had enough velocity to not reform and thus Saturn's rings were formed.

 

One way a planet can be "blown up" without an explosion is via gravity. For example, if Earth had a very close encounter with a similar-sized planet, the gravitational tidal forces would rip both planets apart. The key here is something called the Roche Limit. The Roch limit is determined by mass. For earth, it is somewhere around 10,000 miles in altitude. Anything below that will experience tidal forces (differential gravitational pull) strong enough to overcome its own gravity. The best I can do is give an example: If Earth's moon's orbital altitude was gradually reduced (and it is reducing, due to tidal friction, though on a scale of billions of years) to below around 10,000 miles altitude, the tidal forces would overcome the moon's own gravity, tearing it apart. The resulting rubble would not re-form, but would be pulled into a debris ring.

[Graeme]

Energy and matter can be thought of as just different aspects of the same thing. Einstein's formula (E=MC^2) gives us a formula for this, but it's not as simple as it appears. In general relativity Mass

can vary depending on velocity, so you have relativistic mass. Invariant mass is different; It is the actual mass of an object at rest relative to the observer. In Physics invariant mass is almost always used when speaking of mass, and Einstein used Invariant mass. However, prepare for a headache: E=MC^2 is only generally true *IF* the M is relativistic mass (which Einstein almost never used.)

That's not my recollection.

 

I saw the derivation of the E=MC^2 forumula once, and it was related to applying the Lorenz-Fitzgerald Contractions* to traditional laws of momentum and energy. What Einstein found was that there was a "constant" left over when calculating the energy and that constant was MC^2. It was clear in the derivation that this was the REST mass (what you called the invariant mass), not the relativistic mass.

* The Lorenz-Fitzgerald Contractions are the forumlae that specify how the length of an object appears to decrease, the mass appears to increase, and the rate of time flow for the object alters as an object moves faster. They have been demonstrated empircally by firing sub-atomic particles at high speeds and observing the change in decay rate and mass recorded. I'm not sure if they've demonstrated the theoretical reduction in length.

[C James]

That's not my recollection.

 

I saw the derivation of the E=MC^2 forumula once, and it was related to applying the Lorenz-Fitzgerald Contractions* to traditional laws of momentum and energy. What Einstein found was that there was a "constant" left over when calculating the energy and that constant was MC^2. It was clear in the derivation that this was the REST mass (what you called the invariant mass), not the relativistic mass.

* The Lorenz-Fitzgerald Contractions are the forumlae that specify how the length of an object appears to decrease, the mass appears to increase, and the rate of time flow for the object alters as an object moves faster. They have been demonstrated empircally by firing sub-atomic particles at high speeds and observing the change in decay rate and mass recorded. I'm not sure if they've demonstrated the theoretical reduction in length.

 

I might very well have bungled it as I am going by memory.

 

However, I just hit google and found few references, though I don't consider any conclusive.

Wikipedia

"Einstein's famous equation remains generally true for all observers only if the in the equation is considered to be relativistic mass."

 

http://math.ucr.edu/home/baez/physics/Rela...ty/SR/mass.html

" If this formula is taken to include kinetic energy, then it is only valid for relativistic mass, but it can also be taken as valid in the rest frame for invariant mass. Einstein's conventions and interpretations were sometimes ambivalent and varied a little over the years; however an examination of his papers and books on relativity shows that he almost never used relativistic mass himself. Whenever the symbol m for mass appears in his equations it is always invariant mass. He did not introduce the notion that the mass of a body increases with velocity--just that it increases with energy content. The equation E = mc2 was only meant to be applied in the rest frame of the particle. Perhaps Einstein's only definite reference to mass increasing with kinetic energy is in his "autobiographical notes"."

 

 

 

 

OK, I'll take a stab at this myself, though I'm quite likely wrong:

 

E=MC^2 clearly implies that an object with intrinsic mass cannot reach the speed of light due to intertia: close to the speed of light, adding kinetic energy increases the mass rather than the velocity.

 

However, in general relativity, many things depend on the frame of reference of the observer (the observers relative velocity.) Using E=MC^2, you would get a different value for M depending on your (the observer's) own velocity relative to the object as kinetic energy (speed) changed. Hence, two different observers with different velocities would perceive the object as having different masses. That would mean that the value of E=MC^2 would change for some observers (depending on their relative velocity), meaning that the M in E=MC^2 is relativistic mass. If it was intrinsic mass, M would be the same for all observers.

Edited October 20, 2006 by C James

[Graeme]

For once, I think I have to disagree with Wikipedia.

 

The derivation I saw (and this is over 20 years ago, so my recollection is by no means perfect) was a result of applying the formula for increasing mass with relative velocity to equations of energy. In otherwords, the relative/invariant mass issue was core to the derivation of the equation, and hence the forumula was clearly for the invariant (rest) mass only. The derivation used different symbols for the rest and relativistic mass as part of the calculations so there was no confusion about which was which.

 

This is a classic example of people not understanding the basic assumptions when using an equation. It's like the kinetic energy formula:

 

K.E. = 1/2 M V^2

 

Some people will take this and try to calculate the kinetic energy for a relativistic object by calculating the relativistic mass and plugging it in. However, this formula is derived as the integral of momentum with respect to velocity AND ASSUMES THAT THE MASS DOES NOT VARY WITH VELOCITY.

 

This assumption is a valid approximation at low speeds, but it is invalid at relativistic speeds and hence this formula is invalid for calculating the mass of fast moving objects. I can't remember, but I think it was the attempt to derive the formula for the kinetic energy for relativistic speeds that Einstein's famous equation came from.

[Masked Monkey]

*Snow Dog sighs and takes a deep breath*

 

When Ampere and Faraday were small children, the Electric force and the Magentic force were separate entities, and all that was known of light was it's velocity. Faraday managed to give us induction ... the ability of a changing magnetic field to induce and electric field (well, he thoughtit induced current, but he didn't quite understand). Maxwell, took the known theories of these two forces and found a way to connect them as being aspects of a single force ... the Electromagnetic Force. (One should note that QED-Quantum Electrodynamics is the theory of the Electroweak force that combines the electromagnetic force with the weak force, the one that hold nuclei together, and QCD- Quantum Chromodynamics is the theory that combined the Electroweak Force with the strong force, the one that hold protons and neutrons together).

 

The funny thing about this combined electromagnetic force was that there was a wave equation that developed if there were no electric or magnetic charges. More surprising, this wave traveled in a specific pattern. The electric and magntic fields oscillated perpendicular to the direction of propogation and perpendicular to each other (transverse-propogating). The neat thing is that as the electric field decreases, the magnetic field increases and vice-versa. In essence, this wave travels by having the decreasing electic field induce a magnetic field, and vice versa. Maxwell discovered 2 amazing things about these waves. 1) they traveled at the exact same speed as the best measurments of the speed of light. 2) that they traveled at the same speed independent of the speed of the observer. It is the second feature that is counter-intuitive

 

Given this frame-independent nature of the speed of light, Einstein developed the concept of lorentz contraction. Actually, Lorentz had developed it years before, but it was merely a mathematical device. Much like Riemann geometry before the advent of General Relativity, and Lie algebra long before any uses in magnetic optics. Prof. Einstein's equation E=mc^2 is true ... to an extent. It all depends on what you mean by "m". Properly expressed, E^2 = (pc)^2 + Mo^2c^4 , where p is the momentum, Mo is the mass of the object when it is at rest (in it's own rest frame) and c is the speed of light in vacuum.

 

In the rest frame of an object, it's momentum is zero (p=0) so E^2 = Mo^2c^4 or E = +/- Moc^2 (ignore the - unless you are into tachyons) or E=mc^2. But that doesn't tell the whole picture. To make things easier, the theory of Lorentz contraction came with a factor gamma, that was called the lorentz contraction factor. gamma = 1/square root(1-v^2/c^2). at rest, gamma=1 at the speed of light gamma=infinity, faster than light gamma is imaginary (again, that tachyon thing so ignore it)

 

You can get rid of the silly p^2 thingy and simplify it if you put a gamma in front of the Mo ... In essence, if you incude the lorentz contraction you can write E = gamma Mo c^2 .... where gamma Mo is often called the relativistic mass that goes infinite as you near the speed of light. when you are lazy, this is also written E=mc^2.

 

Edit: I should hassen to add that Kinetic Energy can be written as gamma Mo c^2/2 or (gamma -1) Moc^2

 

So depending on what you mean ... E=mc^2 is either a rest frame statement, a lorentz contracted statement, or simply made by an ignorant person. I will NOT discuss the relativity or time dialation online to anyone who does not have at least a BS in physics. Unless we both have a few (4 or more) hours of undevided attention. Without the ability to do math and draw pictures ... your brain simply cannot absorb it without training.

 

Please not my apologies to Messirs Ampere, Farady, and Einstein for my bastardization of their concepts and notation in order to express what they said in terms of moder explanation and understanding.

 

:king: Snow Dog

Edited October 21, 2006 by Snow Dog

[Graeme]

Thanks, Snow Dog!

 

I learnt something from your post, which is always nice.

 

Cheers!

 

Graeme

[C James]

Thanks Snow Dog! I've saved that for future reference.

 

BTW, do I detect a dislike of Tachyons?

 

Graeme: Thanks, that helped get rid of a few cobwebs between my ears!

[AFriendlyFace]

Well I found this very fascinating! I also couldn't help but think "Gee, when the new forum upgrade happens they can add superscripts with ease and all those formulas will look so much prettier!"

[glomph]

BTW, do I detect a dislike of Tachyons?

 

Sounds like something that gay folk would not like. In my head I can just hear Carson going on about them.

[Graeme]

I personally don't dislike tachyons -- I'm just not convinced they exist. When you start playing with imaginary numbers you get all sorts of weird results. The strange thing is that sometimes you can use them to come up with perfectly rational solutions to problems -- they just appear during a proof of something and disappear by the end.

[C James]

Sounds like something that gay folk would not like. In my head I can just hear Carson going on about them.

 

How... Tacky!

 

I personally don't dislike tachyons -- I'm just not convinced they exist. When you start playing with imaginary numbers you get all sorts of weird results. The strange thing is that sometimes you can use them to come up with perfectly rational solutions to problems -- they just appear during a proof of something and disappear by the end.

 

I'm firmly convinced that either they exist, or they don't.

 

They certainly do present some conundrums if they do exist. However, I'm not inclined to take the lack of conclusive observational data as proof of non-existence: It took around thirty years to detect the Neutrino, and I think it was only in 2002 that one flavor of Neutrino, the Tau, was detected.

 

My guess is that proof, it if ever comes, will be related to the observation of cosmic rays (due to no particle accelerator being capable of anywhere near those energy levels), and the famous "Knee" around 5PeV.

[Kurt]

Wow... this post has really made me feel stupid, I understood about this much of Snowys post: | | Which is not a lot.

 

Kurt

[Eddy]

Wow... this post has really made me feel stupid, I understood about this much of Snowys post: | | Which is not a lot.

 

Kurt

 

OK --- I am going to color myself as being VERY stupid here. I relate to Kurt's post. Snow dogs post is in outer space as far as my brain is concerned. Hang with me on this -- OK?

 

I was far from the brightest light in school. I have no idea what my IQ is - if it was known, I never heard what it was. I have an excellent grasp of common sense and scored VERY high on my entrance tests into the Air Force -- second in my Flight of 120 guys in basic training. When I completed my testing my recruiter sent me back for Officer Training School testing -- which I fell FLAT on my face with -- outer space again!!

 

I am pretty sure sure I am dyslexic but that (dyslexia) all came about after my school days.

 

My question is -- Why is this Greek to some people (me) and not to others? Did I miss something in the courses I took -- or is it logic in my brain that isn't working properly?

 

I know -- this is some really deep do do -- but I wouldn't have asked if I wasn't looking for some honest ideas/answers!! So bring it on -- OK?

 

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

A bit of time has past ---

 

Amazing what one can find on Google!!!

 

Learning disabilities/dyslexia was interesting reading!!!

 

YES -- No doubt that I have dyslexia!!!! Classic case I might add. Sure wish I could do it all over again from the beginning.

 

Now the kids are into drugs, marathon sex, fast food, single parent families and the list goes on. To the young people here, that is not meant as a put down. We all are a product of of our youth. For good or bad.

 

How many of them have learning disabilities and are still not being treated properly? Or are they a product of being treated???

 

Sincere hugs to all

Edited October 21, 2006 by Eddy

[The Reaper]

(Not to sound like i'm barging in on a previous conversation but) I'm w/Eddy on this one, no clue. Even though I am still in High School, I have a pretty good grasp on Physics and anything below. As the great Albert Einstein once said "The important thing is not to stop questioning. Curiosity has its own reason for existing." Eddy, (not to sound like i'm looking down on you or anything but,) for your question on why you cannot unerstand this, is said in one of my most favorite quotes (God i love my quotes).

 

"The most incomprehensible thing about the world, is that it is comprehensible." ~ Albert Einstien

 

Now to some people that is black and white English. But to others, its written in Greek. Why? Beacuse people do not comprehend what they cannot/do not understand. Comprehension and understanding are two completely different things. It is easier to understand than to comprehend.

 

For instance: I understand a tachyon and the correlation between its energy and speed. Yet I do not comprehend it. (I find tachyons to be useful yet worthless)

 

An easier example is one of color. Look at an object that has a definite color. Now surround it in darkness. What color is it now? The answer is, it has no color. Without light, there is no color. Color is what is visible when the object reflects light. If an object's color is green, the object itself is not green. Green is only the result of the light that object reflects. You could say the object "absorbs" the other wavelengths of light. But I won't get into that.

 

If you do not understand what I just said, go back and read it a few more times. When it starts to make sense, apply it into your life and thoughts (or call me wacko). That is just my understanding of comprehension. If you feel I have avoided the question, then i'm sorry that you did not understand my answer.

 

In short, its not that anyone can't learn it (If you read above then you could easily figure everything out), its just that you cannot/did not comprehend it (yet).

 

And on the note of drugs and learning diabilities, i have a HUGE case of ADHD. I normally do not take my meds but I had to this morning because of that damn PSAT. I hate my meds because they make me feel like someone else is "controlling" me. I dont have the spontanious serendipity that I normally do. Although I am glad I took my meds today other wise I would have stopped writing at "Okay, I just".

 

I deffinitely need to stop writing now. I think the medicine is wearing off. I just gaped at a plug for tem minutes then forgot I was hungry.

 

In the immortal words of Al Gore, "Peace out ya'll!"

Edited October 22, 2006 by The Reaper

[JamesSavik]

Theoretically, the most common mechanisms that we know of that might cause a planetary breakup are gravitational shere and a supernova.

 

Gravity Effects:

 

Jupiter: the largest planet in our solar system has the most powerful gravitational field in the solar system with the exception of the Sun.(NASA/JPL)

________________________________________________________________________

This is an image of Shoemaker-Levy after it broke up.(HST/STScI)

________________________________________________________________________

This is Jupiter after getting whacked by Shoemaker-Levy 9.(NASA/JPL)

________________________________________________________________________

 

 

In the late eighties, a periodic comet was discovered called Shoemaker-Levy 9. It wasn't very remarkable but it got a little too close to Jupiter's titanic gravity well and broke apart into a number of splinters. In 1994 that comet actually hit Jupiter. The key here is although Jupiter's gravity broke the comet apart and greatly influenced its movement, the pieces maintained their original momentum. The only change was the vector or direction of that force.

 

Shoemaker-Levy at SEDS

Shoemaker-Levy at Wiki

 

 

Jupiter's moon Io is greatly influenced by Jupiter's gravity Io. (NASA/JPL)

________________________________________________________________________

 

In its encounter with the Jovan system in 1979, Voyager sent back images of Io that astonished scientists because massive volcanic activity was pictured in progress. The only conclusion that could be drawn from Voyager's photos was that either volcanic activity was rare on Io and NASA got very lucky or it was commonplace. Later when the Galileo probe arrived in orbit of Jupiter, it was confirmed. Vulcanism was a common place occurrence on Io- but why?

 

Io is too close to Jupiter's powerful gravitational and magnetic fields for comfort. The action of Jupiter's gravity warps poor little Io out of round by as much as 100 meters at a time. As Io orbits Jupiter, the massive magnetic field rips through the moon like a blender. The action of these two forces combined makes Io the most geologically active body in the solar system.

 

Io Wiki

Voyager 1's Wiki

Galileo Probe Wiki

 

There are several laws of classical physics that apply: Kepler's 3rd Law shows that gravitational force exerted between to bodies declines with distance: the farther two bodies are apart, the weaker the force of gravity between them.

 

Two of Newton's laws of motion apply:

 

First law (law of inertia)

An object will stay at rest or move at a constant speed in a straight line unless acted upon by an unbalanced force.

 

Second law (law of vectors)

The rate of change of the momentum of a body is directly proportional to the net force acting on it, and the direction of the change in momentum takes place in the direction of the net force. (1)

 

 

Destroying the Earth via Gravity

 

The Earth is mostly molten with a spinning nickel-iron core. This gives the Earth a relatively strong magnetic field. The core also acts something like a gyro which helps the Earth maintain its nice, stable orbit.

 

If a very strong gravity field were applied to the Earth, it would warp and deform cracking up along tectonic plates. It would be a bit like an egg cracking up leaking goo- or magma in the case of the Earth. Earth is big and massive enough for its own gravitational field to pull it back into a roughly spherical shape.

 

Different parts of the Earth have very different properties- epically density. A super strong gravitational force applied at right angles to its axis and in opposition to the Sun's gravity would play havoc with the Earth's insides mixing it up like a blender. While this would very effectively wipe out humanity, the Earth will act like ball of thick, viscous molten goo. Any parts, molten or chunky, would still under the influence of the Earth's own gravity which would try to pull it back together.

 

In theory something similar to this may have actually happened during the formation of the solar system during an epoch called the heavy bombardment phase. The theory is that a massive asteroid hit the primordial earth liberating a big blob of magma which eventually became the moon. There is some evidence for this theory. The chemical abundances of the earth and moon are very similar. Proponents of the theory like to point to the geography of the Pacific basin as the impact point.

 

 

Summary: gravity could change the earth's orbit, rewrite the maps or significantly injure Earth and kill all humans(2) but it is unlikely that the Earth will break up. Think of the Earth as silly putty.

_____________________________________________________________________________

 

 

This is a deep field image of Supernova 1987A which occurred in the Large Magellanic Cloud. It is about 120,000 light years away. This is the closest supernova since the middle ages. (ESO)

 

This is the Crab Nebula

which was formed by a supernova in the constellation Taurus in 1731. At its heart is an exotic object called a Neutron Star or the left over core of the old star. It retains the progenitor star's magnetic field and angular momentum. This spinning magnetic dynamo powers the Crab Pulsar. (ESO)

 

Supernova- Most SN occur in stars 20 times as massive as the sun or larger. In fact there are no stars in the size class within many parsecs of earth.

 

A planet around a star that goes supernova could go any one of several ways depending on its distance from its star. Any planets out as far as the orbits of Mars would most likely be vaporized. Distant planets would be exposed to a severe shock wave and would either shatter or be violently ejected from the star system.

 

In theory, a planet destroyed in this manner would blown to highly radioactive bits. Core collapse supernova are the most violent events known. Gamma Ray Bursts from extreme deep space hint at the possibility of even bigger explosions but at this point no one is really sure what GRB's really are.

 

 

Summary: A Supernova could easily vaporize a planet but the Earth is in no danger of a supernova from our G2V class Sun.

_____________________________________________________________________________

 

 

Earth's Most Likely Demise

 

In the far future the Sun will exhaust it nuclear fuel. It's core reaction changes from the Proton-proton Chain reaction to the CNO cycle. The Sun will begin to enter its Red Giant Phase. The Sun will dim somewhat and begin to swell until it encompasses all of the inner planets out to Mars.

Artist conception of a red giant consuming a planet. (Berkley)

 

The inner planets will be surrounded by hot solar plasma of ~7500K. They will be dissolved into the mass of the red giant.

 

The red giant is a dying star losing its grip on its own mass. Slowly the solar plasma will bleed away into space creating a beautiful tomb called a planetary nebulae surrounding the stellar corpse called a white dwarf.

 

This is the Eskimo Nebula (NGC 2392) which illustrates the way plasma bleeds away from star into space. This is a very important process as it enriches the interstellar medium with elements like Carbon, Nitrogen and, Oxygen.

 

________________________________________________________

 

1- Newton's Laws of Motion from Wikipedia article of the same name.

2- I can die happy having worked this phrase into a conversation.

[glomph]

I'm firmly convinced that either they exist, or they don't.

 

That's two of the possibilities.

 

When you start playing with imaginary numbers you get all sorts of weird results. The strange thing is that sometimes you can use them to come up with perfectly rational solutions to problems -- they just appear during a proof of something and disappear by the end.

 

Measuring electro-magnetic stuff can lead to complex results, so I'm not surprised that little particles that behave like waves and such might be similarly measured and described. It all seems weird to those of us who don't go around measuring such things, plus calling something "imaginary" is not likely to inspire confidence in its existence.

 

My main encounter with complex numbers since school came from working with synthesizers. I used some FFT routines to analyze sounds I wanted to imitate, and needed to use complex math to get to the data in which I was interested. On top of that, I had a Yamaha DX7, and needed to expand my math repertoire to program the thing.

 

Theoretically, the most common mechanisms that we know of that might cause a planetary breakup are gravitational shere and a supernova.

 

And infidelity.

[Masked Monkey]

*Snow Dog takes another deep breath*

 

Complex number and the consideration of the complex plane is actually a trick used to apply the same math to two directions at once. Yes, to consider 4D space time, you have 3 imaginary numbers . *Hands out plastic bags to catch exploding brains*

 

Unfortunately, in physics, the math often results in imaginary solutions. Sometimes, based on the application they have meaning, other times, they don't. It really has to do with having equations that describe what you want + another solution. Like the Pythagorean theorm. a^2 + b^2 = c^2. if you solve for "b" and get an imaginary number ... it means you don't have a triangle and the equation doesn't work. Or, you could take the negative root when removing the square, and "c" would be negative .

 

I believe The Reaper commented about light. First off, except at absolute zero, there is always light due to blackbody radiation, just not in the visible. I should also point out that light and vision is a funny thing. Something can look green because either it reflects/emits all light BUT green, or it reflects/emits ONLY green. For instance, green paint absorbs only green, so when you mix all the colors of paint, they absorb everything and it looks black (no light reflected). But when you shine a green laser ... it is only green (most likely), so if you shine all different color lasers together, it looks ... white .. all the colors combined.

 

 

:king: Snow Dog

[AFriendlyFace]

Thank you for those astronomy facts, James! I really enjoyed reading that.

 

Thanks for the refresher about imaginary numers too, Snowy

 

 

's all,

Kevin

[C James]

James, thank you for that great post! I love it!

 

Snowey, Thanks again!

 

BTW, for anyone wanting to experiment with color emission and absorption, an easy way to see the effect is to shine, in a dark room, a laser on a like-colored object. In many cases you get less reflectivity than shining it on something black.

[Eddy]

Thank you for those astronomy facts, James! I really enjoyed reading that.

 

Thanks for the refresher about imaginary numers too, Snowy

's all,

Kevin

 

Kevin is correct on the astronomy facts AND the great photographs. I had not seen the photo of Jupiter's moon Io which is outstanding!!

 

I am on a half dozen or so NASA e-mail lists which produce an endless number of space photographs. Just amazing!!! Makes me think back to my 8th grade Science class with Ms. Hart and her love of astronomy -- How the understanding of our universe has changed during the past 50+ years!!! Ms. Hart was my most favorite teacher -- ever! What she did with her science class was amazing!! Thank you Ms. Hart.

[Masked Monkey]

In a comment on James' pictures and discussion. I don't believe it is an accident that the CNO cycle is the standard death of starts, and that carbon, hydrogen (building blocks of starts) nitrogen and oxygen make up the majority of the basic building blocks of organic matter.

 

Just some food for thought (so to speak )

 

:king: Snow Dog

Edited October 23, 2006 by Snow Dog