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stephanie_dukie
2003-Aug-07, 06:32 PM
If the Sun is such a huge part of our universe and is basically part of the reason we are able to "live", then why is there only 1 sun?

We have numerous planets, numerous star clusters, numerous nebule, but only 1 sun. Why would evolution (which i dont believe in) only evolve us one sun?

IF our sun exploded, would all planets be destroyed or would another sun replace it?

and: Does anyone know when the biggest explosion from the sun has been so far, and how close it actually came to earth? I mean the firey spewey volcanic stuff that erupts.?

Hadrian
2003-Aug-07, 08:48 PM
Not quite sure I know what you mean Stephanie, but the sun is not alone.
While many of the stars in our galaxy are binaries or triples - this being solar systems with two or three stars – one star systems such as our own are not unusual.
One important thing to take into consideration is the radiation thrown off from stars – in a two or three star system any planets that exist around one of those stars would at times be washed in the combined radiation of all three stars, and such a heavy bombardment of varying radiation from two or three such varying sources would make life all but impossible or very very unique. It would certainly not resemble anything like the forms of life we know of on our beautiful planet.

Regards

Adrian

dragonasbreath
2003-Aug-07, 09:05 PM
but there has been one binary/trinary system found with a planet or two orbiting, has there not? Not sure which one or when it was reported, but seem to remember hearing about it.
Granted such heavy radiation would make life as we know it extremely unlikely, but there is always the possiblity that life would find a way!
One of those htings we won't be able to answer until we get there. :rolleyes:

stephanie_dukie
2003-Aug-07, 09:57 PM
So if evolution was indeed true, would that mean that evolution was somehow aware that having 2 "stars" (Suns) would kill the planet(s) around it?

Would a sun (as we know our sun) around pluto affect earth?

I am learning Adrian, and I have been doing just a bit of research about the sun. I am intrigued as to why there is only one actual sun as we know it. If stars are suns, why only one sun?

Forgive me if I sound unclear, this is all quite new for me, and just like Saturn did to me, the sun is now doing to me, and that is grabbing my attention and desire to learn more about it. I find it fasinating that our solar system only has one sun and I want to know why. I understand that multiple suns would radiate us humans to death, but how does evolution know that? And why not another sun for planets in our outer system?

Another question: IF we could...in theory of course... If i stepped out of the ISS with no space suit on (IF I COULD, IF IT WERE POSSIBLE) and I had on shorts & a tee shirt, would the sun bake me right where i stood? Would I live? (as far as the suns affects on me) I understand that it depends on the time of day and where the sun was, say it was 8am when i went outside the ISS.

Fraser
2003-Aug-07, 10:05 PM
The Sun is a very common stars. Whenever you look into the night sky, there are dozens out there with very similar characteristics to the one we orbit. There's absolutely nothing special about our star.

Astronomers believe that binary star systems are bad places for planets. The gravitational interaction between the stars should tend to eject planets out of a star system. It's not an issue of radiation. If there was another star out past the orbit of Pluto, its additional radiation effects would be minimal compared to what we're getting from the Sun.

If you stepped out of the ISS, you would die. It's a cold vacuum, and a very inhospitable place for human life. Here's more info on spacesuits from NASA (http://vesuvius.jsc.nasa.gov/er/seh/suitnasa.html).

Hadrian
2003-Aug-08, 09:41 PM
Yes Stephanie, Frazer has put it nicely.

Our planet has an atmosphere and certain gases within that atmosphere trap the suns heat. On places like Mount Everest – high up where the air is rarefied, it can get incredibly cold, so in retrospect planets without atmospheres are open to space and tend to be cold, unless of course they are very close to a star where the planets surface will bake in the combined heat and radiation of that star.

What caused life to evolve on earth in the first place, we do not know, that we have a magnetosphere, lots of water and other ideal conditions probably helped.

Is life unique to this planet – again we don’t know, and there are plenty of probes on the way to Mars to try to prove otherwise – Mars though, does not have a magnetosphere, so consequently gets washed in the direct radiation of the sun. If Mars ever supported life, I think its unlikely that if does now, because there is little on its barren surface or in its atmosphere to suggest otherwise.

Is life unique to this planet, I think not. Earth could quite easily have been originally seeded with microbes that one day might be found to be common throughout the galaxy, perhaps even the universe.

The stars out there vary, some are like the sun – the star commonly known as Sol, some are much larger and brighter, some smaller, dimmer and denser. The variety is fantastic. Stars burn out and new stars are born. They produce all the elements that life, as we know it is created from. Yes, even stars have a beginning and an end – a life and death cycle. Death and birth stops stagnation setting in, so the constant routine of life and death on earth is really no exception.

And if it were possible to add up the number of galaxies and possible the individual stars contained within those galaxies, the number would be so vast, it would probably beyond the capabilities of human imagining.

Personally, in such a vast and old universe – I like to think that almost anything is possible. Given the time and the resources, humanity will only ever be limited by its imagination, and as Einstein once said, ‘Our knowledge encompasses the world, our imaginations encompass the universe.’ So, if mankind can live past its petty squabbles and silly wars and the urge to amass stockpiles of terrible weaponry, which will one day get used, who knows what fantastic wonders the future holds for us.

Adrian

stephanie_dukie
2003-Aug-08, 10:44 PM
Originally posted by fraser@Aug 7 2003, 06:05 PM
If you stepped out of the ISS, you would die. It's a cold vacuum, and a very inhospitable place for human life. Here's more info on spacesuits from NASA (http://vesuvius.jsc.nasa.gov/er/seh/suitnasa.html).

I understand that part. I was more curious what the sun would do to human being that much closer to it, yet still so far away. Would we bake instantly? Would it be a matter of minutes.

I just want to say something to the people still in school who may get info from this website: Dont do as I did and skim thru school just to pass! I hated science in school, I was more of a math person, but now do I ever regret not taking an interest in Science and learning!
:P :P

Planetwatcher
2003-Aug-10, 08:00 PM
Our Sun is just another star, except it is much closer to us.
Each star in the night sky is another sun. If you were in the solar system of one of those stars and you looked back toward our sun, it would look like just another star.
In fact if you were on the Planet Pluto, the Sun would look not much bigger then most of the other stars.

Now we just happen to have just one sun, but a lot of star systems have 2 or more suns, or stars as they are better known.
The next closest star system to us has three stars. One is yellow like our sun, one is smaller and orange, and the third on is red and very small. For a star that is.
In terms of real size the third one is much bigger then the planet Jupiter. It is also a little closer to us then the other two.

Many of those stars have planets orbiting them, like our planets orbit the Sun.
But because of the distance to these places, we have only been able to detect them for a few years. And even then we have actually seen only a couple as they passed in front of their parent star.
So far we know of 115 planets (give or take 2 or 3) associated with 95 or so stars.

Again because of the great distances, we are finding planets around the size of Saturn and larger with these stars.
An Earth sized planet is still to small to discover with current technology.
But it's speculated there are more out there then we could count, if we had the means of observing them.

stephanie_dukie
2003-Aug-10, 08:27 PM
Planetwatcher,

I just wanted to thank You for your time in explaining what you did about the sun. This is the first time that I have actually got a response that was informative & easy to understand! People like you help make forums a great thing for the newbies. Most of the time, it is hard to understand some of the stuff people respond with because they speak like doctors do, and it makes forums useless for beginners like me!

I thank you from the bottom of my heart for your time & your simple yet very detailed response to my question! :D

Planetwatcher
2003-Aug-10, 08:52 PM
Another star at the distance of Pluto from us would effect us but it's effects depend on the size and temperture of the star.
A Sun like star at the distance of Pluto would not kill us. There may be some differences in tides in the seas, and it may tug at our orbit when we are at our closest point to it. A little more radiation, and a little more light but not nearly as bright as the Moon.

But now a much bigger and hotter star would give more radiation, proabley enough to kill us; make Earth hot enough to kill us if radiation didn't; disrupt our orbit around the sun a a major way, it may even steal us from the Sun and become our new Sun; and the light from it would likely blind us. Take the different between night and day and apply it to an even brighter daylight, and you start to get the idea.
But the distance to Pluto is not an unusual distance between two stars in a binary system. But then neither is the distance of Earth from the Sun.

A planet orbiting two stars could possibley harber life. If the stars are pretty close together and remain the same distance, size and temperture, and the planet orbits both of them in one large orbit which is far enough away to be in the life zone.

Now as for the explosions of the Sun, I wonder if you are refering to solar flares.
They have been known to travel out as much as 1/4 of the way to us before dying out, and are big enough to scorch us if we were to encounter one.

On the other hand if the whole Sun exploding which is called a super nova would vaporize us instintly. But that is not likely because our Sun is too small to supernova. And before it does that it will swell up to a much larger and cooler star,
which could occupy an area the size of the orbit of Jupiter. But again our Sun doesn't have a fraction the mass to do that near the end of it's life cycle.

No our Sun faces a quiet and benign death in about 4 billion years.
It will swell up to maybe Venus's orbit, and just cool off and shrink down to a cold solid ball smaller then the Moon. No super nova, no black hole, no white dwarf, and no pulser. At most maybe it might become a neutron star for a few million years, but nothing more exciting then that.

Now finally if you were closer to the Sun, depending how close will kill unprotected humans.

Think of nuclear bomb exploding right next to you is the best example one can give and in fact is most accurate because the Sun is the result of a giant nuclear chain reaction. Except for it doesn't break down into smaller elements like fission, but fuses together to make larger elements known as fusion.
When all it's fuel has been fused into elements too large to continue to support the fusion the star's death occurs, but that's another story.

Planetwatcher
2003-Aug-10, 09:47 PM
You are welcome. I guess I was composing my second message here while you were thanking me. Then I was posting on another subject and came backto this windown going backwards and found your thanks.
I hope it helped.