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Dragonlor
March 8th, 2008, 07:25 AM
I'm no astronomer, but doesn't the evolution of a star take place on the timescale of millions and billions of years and not 48,000? The star should not have been able to drastically change the planet to such an extent in such a small period of time. And only an additional 500 years to completely remove the atmosphere sounds even more suspect.

I still enjoyed the episode though.

Celleye
March 8th, 2008, 07:33 AM
I'm no astronomer either, but maybe the star was close to its ending when sheppard got teleported? Not like it was born the day sheppard time traveled. :p

Heaven
March 8th, 2008, 07:59 AM
yep, you're right
there's also the matter that if it boiled out the ocean
there shouldn't have been breathable atmosphere in atlantis at all

not to mention the planet should have been scorched with fires and lava filling the horizon, not a desert :)

The_Carpenter
March 8th, 2008, 08:02 AM
yep, you're right
there's also the matter that if it boiled out the ocean
there shouldn't have been breathable atmosphere in atlantis at all

not to mention the planet should have been scorched with fires and lava filling the horizon, not a desert :)
They should of stuck with the original Ice Age idea, but then we wouldn't of got the cool shots of Atlantis in the dunes so.

Though to be fair we don't know that the ocean turned into a desert because of the sun could of been something else :S

Dr.Mckay
March 8th, 2008, 08:06 AM
Well everything in the Universe formed when the Big bang occured, roughly 10 billions years ago. The ancients, or alterans were at most, 100 million years old. When they got to Earth, some 50 million years ago, and moved to PG, some 20 million years ago, the Solar systems in PG would've already formed and was probably in its mid stage-death. Remember, the ancients didn't create PG, so most of their solar systems ages are undetermined, the sun could've been dying when the ancients got there, and it takes a few million years to actually turn into a red giant, so when Sheppard was put in the future, it would be the time when the Sun would die.
But yeah, the sand dunes are actually very scifi, cause when the Sun gets hotter, it should just heat the water so that it evaporates and leave the ground empty, but filled with sand? Not sure about that.
Maybe under neath the water is sand? o.o

Gate Geek
March 8th, 2008, 09:45 AM
Well I'm glad to see other people have issues with the whole sun thing as well.

Assuming the star was of average mass and age (compared to our own Sun), it can be somewhat safe to assume then, it should be about 1/2 way through its life time of about 10 billion years. Being transported 48,000 years into the future is not going to make the star into a super giant, nor would it have boiled off all the planets water.

If the star was already approaching the super giant phase, the planet would not have been hospitable to life when Atlantis landed on it earlier this season. Our own planet will most likely become inhospitable to life in only a billion years - well before the red giant stage (in five billion years) becaue the Sun is burning hotter as it consumes the last of it fuel.

Now assuming the star is more massive (which will equal a shorter life span of about 10 million years), 48,000 years to turn it into a red giant isn't kosher either. Once again, you ahve the dilemma that if its very near that stage, the planet would have already been inhospitable to life.

The only conclusion I can come up with for the sun probelm, it's science fiction show. *shrugs*

Vala_M
March 8th, 2008, 09:46 AM
They should of stuck with the original Ice Age idea, but then we wouldn't of got the cool shots of Atlantis in the dunes so.

Though to be fair we don't know that the ocean turned into a desert because of the sun could of been something else :S

Where is the mention of it being ice originally?

Vala,

Dr.Mckay
March 8th, 2008, 09:51 AM
Well I'm glad to see other people have issues with the whole sun thing as well.

Assuming the star was of average mass and age (compared to our own Sun), it can be somewhat safe to assume then, it should be about 1/2 way through its life time of about 10 billion years. Being transported 48,000 years into the future is not going to make the star into a super giant, nor would it have boiled off all the planets water.

If the star was already approaching the super giant phase, the planet would not have been hospitable to life when Atlantis landed on it earlier this season. Our own planet will most likely become inhospitable to life in only a billion years - well before the red giant stage (in five billion years) becaue the Sun is burning hotter as it consumes the last of it fuel.

Now assuming the star is more massive (which will equal a shorter life span of about 10 million years), 48,000 years to turn it into a red giant isn't kosher either. Once again, you ahve the dilemma that if its very near that stage, the planet would have already been inhospitable to life.

The only conclusion I can come up with for the sun probelm, it's science fiction show. *shrugs*

Well i don't think the writers have a degree in astronomy do they? lol

Corgano
March 8th, 2008, 10:02 AM
Well i don't think the writers have a degree in astronomy do they? lol

The story could still work if the star in the system is really huge! Then it would have an extremly short lifespan (some 100k years tops).

Shan Bruce Lee
March 8th, 2008, 10:23 AM
I'm willing to accept that they might have just f***ed up here, but, in my own head, what really happened will never be known because McKay probably screwed up again and just programmed the hologram to lie to Shep so he wouldn't know when he got back to the present timeline.

I mean come on... McKay & Keller? :p

placid
March 8th, 2008, 10:37 AM
There's another big hole in this sun plot; if McKay had never counted on it dying, then his flare predictions were based on it being normal. Besides that these wouldn't apply, a dying sun would probably have a very different surface and I imagine flares would be somewhat harder to predict and more volatile in nature, making Sheppard's return impossible.

RepliVeggie
March 8th, 2008, 10:41 AM
There's another big hole in this sun plot; if McKay had never counted on it dying, then his flare predictions were based on it being normal. Besides that these wouldn't apply, a dying sun would probably have a very different surface and I imagine flares would be somewhat harder to predict and more volatile in nature, making Sheppard's return impossible.

He configured the sensors while Shepphard was there. Not before he died. So it works.

Gate Geek
March 8th, 2008, 10:42 AM
The story could still work if the star in the system is really huge! Then it would have an extremly short lifespan (some 100k years tops).

If that was the case, the lifetime of the star would be too short for any planets around it to even evolve to the point of being conductive to life. I can't see that as being a plausible option either.

And well, if the star was that huge, we'd be talking supernova explosion probably resulting in a black hole rather than a neutron star and I wouldn't want to consider being around a star like that regardless of its stage. :cool:

Durgia
March 8th, 2008, 10:45 AM
Its possible the Wraith or other baddy sped up the death of the star to destroy Atlantis.

And I don't think they were using the local star to make the flare, but the same star that caused the original one.

kymeric
March 8th, 2008, 11:44 AM
It dosent really take much change for a sun to make a habitable planet inhabitable. Just a change of 5-10 degrees would be enough to kill everything. And once the plants and oceans are gone its just a matter of time before a planet goes to sand. Look at it like Earth into Mars into a giant sand ball into a steaming molten rock then its swallowed by its sun. Venus is in the other direction, like earth long before it became habitable through changing enviromental factors and the huge impact of emerging bacterial life.

rens14
March 8th, 2008, 11:54 AM
It dosent really take much change for a sun to make a habitable planet inhabitable. Just a change of 5-10 degrees would be enough to kill everything. And once the plants and oceans are gone its just a matter of time before a planet goes to sand. Look at it like Earth into Mars into a giant sand ball into a steaming molten rock then its swallowed by its sun. Venus is in the other direction, like earth long before it became habitable through changing enviromental factors and the huge impact of emerging bacterial life.
I agree because 15.000 years ago we had an ice age so earth so without changes in the sun so small changes in the sun can have very big effects on a planets

Mitchell82
March 8th, 2008, 12:02 PM
I'm no astronomer, but doesn't the evolution of a star take place on the timescale of millions and billions of years and not 48,000? The star should not have been able to drastically change the planet to such an extent in such a small period of time. And only an additional 500 years to completely remove the atmosphere sounds even more suspect.

I still enjoyed the episode though.

If it evolved naturally yes. But there are many things that could cause a problem with the natural evolution of the sun.

Demerzel
March 8th, 2008, 12:11 PM
It comes down to this.

We don't know the age of the current planet's sun at the time that Atlantis settled down on it. If when Atlantis arrived, the sun was already near turning into a red giant, then 48,000 years could be realistic period of time. There is also the factor of how far away the planet is from the sun.

To give an example, our sun will turn into a Red Giant in 5-6 billion years, and it's already 4.57 billion year old. So either the sun in Atlantis's solar system is reaaaaally old, considering the universe itself is 13.7 billion year old, or the writers again are showing their ignorance when it comes to astronomy.

There's no easy answer to this one, we don't have enough details to come to a decent conclusion.

SP90
March 8th, 2008, 04:19 PM
Glad someone decided to start this thread. I also found it confusing how the star in the Atlantis system can change so suddenly. I mean 48,000 years is like a blink of an eye relative to the age of a normal G type star like that. It would have been more plausible if they said something shifted the orbit of the planet like in ST:II. That being said, it is sci-fi. If the Asgard can artificially increase the mass of a star and turn it into a black hole then maybe someone found a way to speed up the rate the Atlantis star consumes it's fuel supply.

PG15
March 8th, 2008, 04:56 PM
Assuming the star was of average mass and age (compared to our own Sun), it can be somewhat safe to assume then, it should be about 1/2 way through its life time of about 10 billion years. Being transported 48,000 years into the future is not going to make the star into a super giant, nor would it have boiled off all the planets water.

Unless, of course, the star formed 10 billion years ago, which would mean that it's nearly 100% though its main-sequence life time. Not all stars formed at the same time as the sun.


If the star was already approaching the super giant phase, the planet would not have been hospitable to life when Atlantis landed on it earlier this season. Our own planet will most likely become inhospitable to life in only a billion years - well before the red giant stage (in five billion years) becaue the Sun is burning hotter as it consumes the last of it fuel.

Unless, of course, that this planet WASN'T hospitable a few billion years ago, and only got its oceans when the sun grew hot enough so that the habitable zone extended to where the planet was. This, I think, is the crux of the matter that you forgot to think about.

Or I'm completely wrong about this, whatever. :D

Gate Geek
March 9th, 2008, 06:53 AM
Unless, of course, the star formed 10 billion years ago, which would mean that it's nearly 100% though its main-sequence life time. Not all stars formed at the same time as the sun.

Unless, of course, that this planet WASN'T hospitable a few billion years ago, and only got its oceans when the sun grew hot enough so that the habitable zone extended to where the planet was. This, I think, is the crux of the matter that you forgot to think about.

Or I'm completely wrong about this, whatever. :D

I know not all stars formed the same time as our Sun. But if the sun did form 10 billion years ago and its very near the end of its life, it would still have made the planet inhospitable long before this point.

I admit I'm not sure what you're getting at in the second paragraph. :o Could you please clarify for me.

Ack! My brain is tired of this science stuff. I'm gonna give it a rest.

rob_squared
March 9th, 2008, 08:16 AM
I'm no astronomer, but doesn't the evolution of a star take place on the timescale of millions and billions of years and not 48,000? The star should not have been able to drastically change the planet to such an extent in such a small period of time. And only an additional 500 years to completely remove the atmosphere sounds even more suspect.

I still enjoyed the episode though.

There just might be a way to explain this, but it'd be kind of weird. Perhaps atlantis was moved to a different planet again, one that had sand dunes. Maybe after Rodney programmed the hologram it became necessary to hide atlantis on a world like that, one that had a red giant star but had a planet far enough away to become habitable. And as far as sheppard gating to the planet where atlantis used to be, someone from atlantis put a macro there and forwarded sheppard to where atlantis is in the future. The tricky part is explaining how they got sheppard forwarded back to atlantis once they used the flare to get him back to his current time. I'm having trouble justifying that part without using a generic time machine (for obvious reasons).

(fixing plot holes has become a hobby of mine)

The_Carpenter
March 9th, 2008, 08:41 AM
Where is the mention of it being ice originally?

Vala,
It was in Alex Levines blog, I don't have a link unfortunatly it should be the latest entry

Cory Holmes
March 9th, 2008, 08:58 AM
I admit I'm not sure what you're getting at in the second paragraph. :o Could you please clarify for me.

Earth exists in a narrow band of space where the heat energy of the sun is juuuuust enough to have liquid water. If Earth with a little closer, it'd be hot and all the water would boil away. A little farther, and it'd all be locked up in solid ice.

Now we know that a star's energy output will vary over time as it goes through it's life cycle. It's known that that our sun and it's habatibility range hasn't always been centred around Earth and that as it evolves out of the Main Sequence and into its later life that zone will expand outward as the sun does.

So what PG15 was trying to suggest that perhaps the planet that Atlantis landed on in Lifeline is farther out in its solar system and the primary star has already evolved into (or nearly into) the Red Giant phase. So that 48,000 years was enough time for the star to push that zone even farther out and wreak havoc on the planet.

In fact, that could be one reason why the A-Team ignored that planet when they were first searching for a new home, and only went to that when Weir was abducted by the Replicators.

PG15
March 9th, 2008, 10:44 AM
Uh...yeah, what he said. :D

Gate Geek
March 9th, 2008, 10:45 AM
Earth exists in a narrow band of space where the heat energy of the sun is juuuuust enough to have liquid water. If Earth with a little closer, it'd be hot and all the water would boil away. A little farther, and it'd all be locked up in solid ice.

Now we know that a star's energy output will vary over time as it goes through it's life cycle. It's known that that our sun and it's habatibility range hasn't always been centred around Earth and that as it evolves out of the Main Sequence and into its later life that zone will expand outward as the sun does.

So what PG15 was trying to suggest that perhaps the planet that Atlantis landed on in Lifeline is farther out in its solar system and the primary star has already evolved into (or nearly into) the Red Giant phase. So that 48,000 years was enough time for the star to push that zone even farther out and wreak havoc on the planet.

In fact, that could be one reason why the A-Team ignored that planet when they were first searching for a new home, and only went to that when Weir was abducted by the Replicators.


That's what I thought, but didn't want to assume wrong, respond and get blasted for it. It seems to happen alot in some threads. :S Better to ask for clarification first.

That scenario could work. But the planet would have to pretty damned far out though. ;) If I think of our solar system and our sun, our sun when it reaches the red giant phase will swallow up the orbits of Mercury and Venus and nearly extend to Earth. The possible habitable area in our Solar System then would be some of the moons of Jupiter or Saturn which currently show strong evidence of oceans of water covered by layers of ice.

You're right, habitable zones can come come and go and in be lots of different places as discovered in our own solar system (Mars mostl likely had liquid oceans of water on its surface in the past, Jupiter has moons with oceans of water underneath their surfaces - most likely their interiors being heated by the tug of Jupiter's gravity and there is evidence that some of Saturn's moons may have oceans of water as well.)

It's a pretty tight balancing act for a planet to be habitable and pretty damned amazing life exists at all.

Vala_M
March 10th, 2008, 05:00 PM
It was in Alex Levines blog, I don't have a link unfortunatly it should be the latest entry

Thanks. I found it on Google.

Vala,

ZixPax
March 11th, 2008, 07:26 AM
A star with mass 5x times the sun go through the following

6,44*10^7 yr Hydrogen burning in core(
2,2*10^6 yr Overall contraction phase
1,4*10^5 yr Establishment os shell source
1,2*10^6 yr Hydrogen burning in thick shell
8*10^5 yr Shellnarrowing phase
5*10^5 yr Red-Giant phase

The earht sun is in the Hydrogen burning core phase.

I think it showes that there may be a problem with the idea that the sun could go redgiant in 48.000.
simply because when increasing the mass you reduce the time it takes for the star to go from hydrogen burning in the core to redgiant you also reduce the time it take for the star to burn up all the hydrogen in the core.
And a planet dosen't form i a matter of years:mckayanime09:

Cory Holmes
March 11th, 2008, 09:41 AM
There doesn't need to be a tremendous change in stellar output in order to affect a planet. If the Earth were orbiting as little as 5% closer or farther from the sun, then we wouldn't have the proper conditions to have all three phases of water present.

There had to be a reason why this world wasn't originally considered to be Atlantis' new home. Perhaps stellar instability or late-life had something to do with it.

Blanche
March 18th, 2008, 01:48 AM
I just rewatched Echoes from season 3 and I had to think about TLM.

Maybe one of these corona blast things was responsible for heating up the planet and makeing the ocean a desert.
McKay said this stuff comes up kind of every 15,000 years, so it would have happend twice by the time shep arrives in the future

PG15
March 18th, 2008, 07:39 PM
That was a different sun from this one.

Though I guess it's certainly possible that this sun can do the same thing.

Amalthea
March 19th, 2008, 01:01 PM
The only problem with the idea that they knew the star was older when they landed is that HoloMcKay shouldn't have been surprised that the sun was going nova when John got there. These things are pretty predictable, from what I understand.

That said, it's a convenient explanation of the environment. I'm willing to go with them on it since it is sci fi. Maybe someone experimented on the sun after the expedition left since they didn't know Atlantis was there. It was a secret that in theory, only Todd knew and he got blowed up.

Besides, how else are we going to get Shep all sand blasted? lol

KlaxxonBlue
May 31st, 2008, 07:35 AM
You are correct. Stars lives and transitions through the cycles of its life occurs over periods of Billions of years. The transition shown in SGA was WAY too fast.

KlaxxonBlue

mike123
June 25th, 2008, 03:10 PM
First of all, all of you are saying that the star evolved. Now I know that in the Stargate universe, evolution is supposedly true. But how can you believe that that all of this order came out of such a chaotic moment as the Big Bang. Eventually, at some point in your life, you will realize that there is evidence of design. Now whether or not you like it, you will realize it.

GateDragon
June 25th, 2008, 03:13 PM
I'm no astronomer, but doesn't the evolution of a star take place on the timescale of millions and billions of years and not 48,000? The star should not have been able to drastically change the planet to such an extent in such a small period of time. And only an additional 500 years to completely remove the atmosphere sounds even more suspect.

I still enjoyed the episode though.

it's a alien sun/.....

jenks
June 25th, 2008, 03:16 PM
First of all, all of you are saying that the star evolved. Now I know that in the Stargate universe, evolution is supposedly true. But how can you believe that that all of this order came out of such a chaotic moment as the Big Bang. Eventually, at some point in your life, you will realize that there is evidence of design. Now whether or not you like it, you will realize it.

There is zero evidence of design. I wish I were confident you'd realise this at some point in your life, but unfortunately I'm not. On a lighter note - LOL.

mike123
June 25th, 2008, 03:35 PM
There is zero evidence of design. I wish I were confident you'd realise this at some point in your life, but unfortunately I'm not. On a lighter note - LOL.

How can you say there is not design. Everyone has there own personal view of life (some are the same and some of are not) and I am not trying to conform the entire world to my view (even though that would be nice).

So, Jenks, are you saying that all of this order came out of a chaotic moment such as the Big Bang. How was the energy there if there wasn't anything there to begin with?

jenks
June 25th, 2008, 03:43 PM
How can you say there is not design. Everyone has there own personal view of life (some are the same and some of are not) and I am not trying to conform the entire world to my view (even though that would be nice).

So, Jenks, are you saying that all of this order came out of a chaotic moment such as the Big Bang. How was the energy there if there wasn't anything there to begin with?

I don't know. Regardless, there is still no evidence of design. Our lack of understanding doesn't add any weight to the idea that there is some sort of supernatural answer out there, a thousand years ago we didn't know what caused volcanoes or earthquakes, that doesn't mean that they're 'acts of God', though the ignorant majority of the time would of had you believe so.

mike123
June 25th, 2008, 03:51 PM
igornant?

jenks
June 25th, 2008, 03:54 PM
What?

mike123
June 25th, 2008, 04:26 PM
I don't know. I guess I was a little offended by that. What do you mean by ignorant majority?

jenks
June 25th, 2008, 04:37 PM
The majority of people, if not all people back then wouldn't have known how earthquakes and other natural disasters occur, they'd have been ignorant of their causes and would have attributed them to something supernatural like a god or demon or something. Wrongly.

PG15
June 26th, 2008, 12:26 AM
First of all, all of you are saying that the star evolved. Now I know that in the Stargate universe, evolution is supposedly true. But how can you believe that that all of this order came out of such a chaotic moment as the Big Bang. Eventually, at some point in your life, you will realize that there is evidence of design. Now whether or not you like it, you will realize it.

...

Seriously?

This is going to be good. It's not even the same kind of evolution.

SGFerrit
June 26th, 2008, 02:39 AM
I 'Thank god' (:D) that most people nowadays have seen past 'creationism' and 'design', and realised that evolution is much more likely to be the true force in this universe. Well, here in Britain at least.

And no, conforming to that view would not be 'nice' at all. People totally avoiding the facts and the evidence and believeing in something much less realistic, taking a massive step backwards from where we are now? Sounds a little like the dark ages to me.