That's right folks, a terrestrial exoplanet has been found. It is located in the habitable zone around Gliese 581 (which has 6 planets discovered so far), and is 20 ly away.
http://www.bbc.co.uk/news/science-environment-11444022
Quote from: Doktor Blight on October 02, 2010, 02:01:12 AM
That's right folks, a terrestrial exoplanet has been found. It is located in the habitable zone around Gliese 581 (which has 6 planets discovered so far), and is 20 ly away.
http://www.bbc.co.uk/news/science-environment-11444022
Great. Let's go there and get all Cortez on the bastards.
This is amazing! :D
OHAI, ALIENS! WE COME IN PEACE!
\
(https://resourcesforhistoryteachers.wikispaces.com/file/view/hernando-cortez-7.jpg/81749669/hernando-cortez-7.jpg)
Would you like some blankets?
Quote from: Doktor Howl on October 02, 2010, 02:17:20 AM
OHAI, ALIENS! WE COME IN PEACE!
\
(https://resourcesforhistoryteachers.wikispaces.com/file/view/hernando-cortez-7.jpg/81749669/hernando-cortez-7.jpg)
\
DO YOU GUISE WANT TO MAKE US YOUR GODZ?
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:13:40 AM
This is amazing! :D
I'm waiting for them to find out what the atmosphere is like. That's an obstacle for Earth-like life to be present, and not just for the weather problems they mention.
Since it doesn't rotate, it likely does not have a very strong magnetosphere to protect it from Gliese's radiation.
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
True, and we gave them a heads up that we're here- several months ago a bunch of people sent a variety of messages to another one of the planets in that system, since it was close to Earth sized (in actuality it is probably a gas giant that had most of its atmosphere stripped off).
I remember one of the messages too.
It said something like, "Hello Mr. Alien, please don't come and eat us."
Now, I don't know about aliens, but a human would do the complete opposite of that.
Quote from: Doktor Blight on October 02, 2010, 02:21:20 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:13:40 AM
This is amazing! :D
I'm waiting for them to find out what the atmosphere is like. That's an obstacle for Earth-like life to be present, and not just for the weather problems they mention.
Since it doesn't rotate, it likely does not have a very strong magnetosphere to protect it from Gliese's radiation.
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
We won't be leaving Earth anytime soon, if ever.
Also, I finally found a science topic I could initiate a thread about :D
Twid,
-Likes space and shit, as long as no extensive math is involved
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that
crash. We can do THAT.
Quote from: Doktor Howl on October 02, 2010, 02:28:56 AM
Quote from: Doktor Blight on October 02, 2010, 02:21:20 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:13:40 AM
This is amazing! :D
I'm waiting for them to find out what the atmosphere is like. That's an obstacle for Earth-like life to be present, and not just for the weather problems they mention.
Since it doesn't rotate, it likely does not have a very strong magnetosphere to protect it from Gliese's radiation.
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
We won't be leaving Earth anytime soon, if ever.
True, but if we can get through the next couple of hundred years and still have the capability to leave the planet, it would be a good time to start working on being able to do so.
I know it won't be in my lifetime one way or the other, but I like the idea of it eventually happening.
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
Quote from: Doktor Blight on October 02, 2010, 02:31:42 AM
Quote from: Doktor Howl on October 02, 2010, 02:28:56 AM
Quote from: Doktor Blight on October 02, 2010, 02:21:20 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:13:40 AM
This is amazing! :D
I'm waiting for them to find out what the atmosphere is like. That's an obstacle for Earth-like life to be present, and not just for the weather problems they mention.
Since it doesn't rotate, it likely does not have a very strong magnetosphere to protect it from Gliese's radiation.
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
We won't be leaving Earth anytime soon, if ever.
True, but if we can get through the next couple of hundred years and still have the capability to leave the planet, it would be a good time to start working on being able to do so.
I know it won't be in my lifetime one way or the other, but I like the idea of it eventually happening.
I think in the next couple of hundred years, we'll be avoiding the Cities of the Ancients, due to the horrible ghosts.
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
Quote from: Doktor Howl on October 02, 2010, 02:33:52 AM
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
I love how the Welsh thing is really taking off here. :lulz:
Quote from: Why Sig should not be allowed to meet the aliens
HOORAY!
WE ARE SO GLAD TO MEET YOU!
THIS IS THE SHIP "PLAY GAMES FOR LOTS OF FUN"
(OPERATED BY CHARGED PARTICLE FINANCIAL FIRMS)
WE LOVE YOU AND WE WANT YOU TO BE SUPER HAPPY.
WOULD YOU LIKE TO HAVE SEX?
Quote from: Sigmatic on October 02, 2010, 02:36:04 AM
Quote from: Why Sig should not be allowed to meet the aliens
HOORAY!
WE ARE SO GLAD TO MEET YOU!
THIS IS THE SHIP "PLAY GAMES FOR LOTS OF FUN"
(OPERATED BY CHARGED PARTICLE FINANCIAL FIRMS)
WE LOVE YOU AND WE WANT YOU TO BE SUPER HAPPY.
WOULD YOU LIKE TO HAVE SEX?
This is why Sig SHOULD meet the aliens.
I gotcher back. Way back.
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:35:02 AM
Quote from: Doktor Howl on October 02, 2010, 02:33:52 AM
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
I love how the Welsh thing is really taking off here. :lulz:
It's so over the top that it works. Don't tell Nigel or Cudgel I said that.
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:35:02 AM
Quote from: Doktor Howl on October 02, 2010, 02:33:52 AM
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
I love how the Welsh thing is really taking off here. :lulz:
There's so much to work with, and the usual reaction is for someone to go "But I'm not fucking Welsh!" or Nigel going :crankey:
Edit for emote fail
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
i SHALL HUNT YOU DOWN.
Quote from: Doktor Blight on October 02, 2010, 02:38:10 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:35:02 AM
Quote from: Doktor Howl on October 02, 2010, 02:33:52 AM
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
I love how the Welsh thing is really taking off here. :lulz:
There's so much to work with, and the usual reaction is for someone to go "But I'm not fucking Welsh!" or Nigel going :crankey:
Edit for emote fail
Just keep it up you blasted potato eater.
Quote from: Doktor Howl on October 02, 2010, 02:36:50 AM
Quote from: Sigmatic on October 02, 2010, 02:36:04 AM
Quote from: Why Sig should not be allowed to meet the aliens
HOORAY!
WE ARE SO GLAD TO MEET YOU!
THIS IS THE SHIP "PLAY GAMES FOR LOTS OF FUN"
(OPERATED BY CHARGED PARTICLE FINANCIAL FIRMS)
WE LOVE YOU AND WE WANT YOU TO BE SUPER HAPPY.
WOULD YOU LIKE TO HAVE SEX?
This is why Sig SHOULD meet the aliens.
I gotcher back. Way back.
I would bring one of those little caps that you could crack with your teeth, and they contained cyanide. Except mine will be roofies.
Quote from: Sir Coyote on October 02, 2010, 02:43:27 AM
Quote from: Doktor Blight on October 02, 2010, 02:38:10 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:35:02 AM
Quote from: Doktor Howl on October 02, 2010, 02:33:52 AM
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
What are the odds of TWO planets producing the Welsh? I call malevolent deity.
I love how the Welsh thing is really taking off here. :lulz:
There's so much to work with, and the usual reaction is for someone to go "But I'm not fucking Welsh!" or Nigel going :crankey:
Edit for emote fail
Just keep it up you blasted potato eater.
I will. Potatoes are excellent, way better than coal and gravy with a side of mutton
Quote from: Sigmatic on October 02, 2010, 02:44:22 AM
Quote from: Doktor Howl on October 02, 2010, 02:36:50 AM
Quote from: Sigmatic on October 02, 2010, 02:36:04 AM
Quote from: Why Sig should not be allowed to meet the aliens
HOORAY!
WE ARE SO GLAD TO MEET YOU!
THIS IS THE SHIP "PLAY GAMES FOR LOTS OF FUN"
(OPERATED BY CHARGED PARTICLE FINANCIAL FIRMS)
WE LOVE YOU AND WE WANT YOU TO BE SUPER HAPPY.
WOULD YOU LIKE TO HAVE SEX?
This is why Sig SHOULD meet the aliens.
I gotcher back. Way back.
I would bring one of those little caps that you could crack with your teeth, and they contained cyanide. Except mine will be roofies.
Sigmatic, pioneer of alien date rape.
All I can say is, I would gladly be the first person to die that way. History books, here I come.
...And there he goes...
Quote from: Sigmatic on October 02, 2010, 02:48:50 AM
All I can say is, I would gladly be the first person to die that way. History books, here I come.
...And there he goes...
Patient zero for every space STD :lulz:
I will date the girl from Venus
Flowers die and so will I
Yes, I will kiss the girl from Venus FOR SCIENCE!
Quote from: Sigmatic on October 02, 2010, 02:52:19 AM
I will date the girl from Venus
Flowers die and so will I
Yes, I will kiss the girl from Venus FOR SCIENCE!
You'll make a fine starship captain one of these days
Someone's got to do it right.
Kirk style. Fuck yeah.
That Frankenstein-looking SOB Brian Williams was covering this on the NBC Evening News last night. He ended the bit by saying (paraphrasing), "It's good to know if we screw this place up there is somewhere else to go." Completely glossing over the whole idea that the place could support life. You know, life that might not be super cool about 40 Billion Ass-hat Earthlings descending upon their planet to pound their flags into their planet's crust. I mean, if it were the other way around, and they were coming here, it would be fucking Star Wars baby. The US and Russia would be pointing their nukes into space and blasting the bastards.
Attackers have the advantage, if they know how to drop rocks down the gravity well.
Quote from: Sigmatic on October 02, 2010, 04:02:05 AM
Attackers have the advantage, if they know how to drop rocks down the gravity well.
Great now you have me thinking about how to devastate a planetary population quickly from orbit but not devestat the planet to the extent that easy initial colonization would occur.
I'd say just drop shit on the cities. It couldn't take more than 200 earth tons of material to destroy almost all the cities of a planet similar to ours.
Quote from: Sigmatic on October 02, 2010, 04:12:13 AM
I'd say just drop shit on the cities. It couldn't take more than 200 earth tons of material to destroy almost all the cities of a planet similar to ours.
The question is how much shit would be knocked into the atmosphere and for how long.
Quote from: Doktor Blight on October 02, 2010, 02:21:20 AM
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
This planet is probably tidally locked (the day night cycle is very very long). On the very off chance it actually has an atmosphere, there would be constant winds taking scorching hot air to the night side and bringing cold air back from a place that makes Antartica look like the tropics. Red Dwarfs aren't stable either, I don't have the specifics for this star, but output of Red Dwarfs can drop by as much as 40% (lasting months) and some of them will also occasionally double in brightness for a brief period, so be prepared for the fucked up weather to get even *more* fucked up as soon as the star decides it doesn't want to play ball anymore.
To top it all off the narrow habitable dusk band will *move* which means next year, or maybe next millennium (these things can be very slow), your brand new colony is going to slip right out of the habitable zone, and everyone there will either freeze or roast, depending on which way it goes.
Quote from: Sir Coyote on October 02, 2010, 04:23:44 AM
Quote from: Sigmatic on October 02, 2010, 04:12:13 AM
I'd say just drop shit on the cities. It couldn't take more than 200 earth tons of material to destroy almost all the cities of a planet similar to ours.
The question is how much shit would be knocked into the atmosphere and for how long.
The more, the better. Remember: You're in a starship, and they're at the bottom of a gravity well. You've got time to wait while crop-killing dust settles, and resistance fighters die off.
Quote from: Sigmatic on October 02, 2010, 04:33:32 AM
Quote from: Sir Coyote on October 02, 2010, 04:23:44 AM
Quote from: Sigmatic on October 02, 2010, 04:12:13 AM
I'd say just drop shit on the cities. It couldn't take more than 200 earth tons of material to destroy almost all the cities of a planet similar to ours.
The question is how much shit would be knocked into the atmosphere and for how long.
The more, the better. Remember: You're in a starship, and they're at the bottom of a gravity well. You've got time to wait while crop-killing dust settles, and resistance fighters die off.
That gave me a thought. Given a society with the technology for interstellar travel at sub-luminary velocities I guess if that society sent several waves of large kinetic kill projectiles decades or centuries ahead of the initial colonization force, by the the time the colonists arrived much of the indigenous life would have been kill off and there might possibly be more favorable conditions due to the dust having settled.
That is ridiculously convenient! Nice thinking!
Hell, you could even calculate how long it would be between impact and arrival, and salt the projectiles with radioactive substances with an appropriate decay cycle, to aid in biological life extermination.
This idea has a certain deadly perfection to it.
Quote from: Sigmatic on October 02, 2010, 05:10:33 AM
That is ridiculously convenient! Nice thinking!
Hell, you could even calculate how long it would be between impact and arrival, and salt the projectiles with radioactive substances with an appropriate decay cycle, to aid in biological life extermination.
This idea has a certain deadly perfection to it.
I sometimes have moments of insight into weird shit while impaired by alcohol. Although it was you who sparked the initial train of thought.
This thread is a good example of why we can't have nice things. :cry:
Quote from: Requia ☣ on October 02, 2010, 04:29:02 AM
Quote from: Doktor Blight on October 02, 2010, 02:21:20 AM
Interesting destination for future colonization prospects though, once we figure out to go a little bit faster.
This planet is probably tidally locked (the day night cycle is very very long). On the very off chance it actually has an atmosphere, there would be constant winds taking scorching hot air to the night side and bringing cold air back from a place that makes Antartica look like the tropics. Red Dwarfs aren't stable either, I don't have the specifics for this star, but output of Red Dwarfs can drop by as much as 40% (lasting months) and some of them will also occasionally double in brightness for a brief period, so be prepared for the fucked up weather to get even *more* fucked up as soon as the star decides it doesn't want to play ball anymore.
To top it all off the narrow habitable dusk band will *move* which means next year, or maybe next millennium (these things can be very slow), your brand new colony is going to slip right out of the habitable zone, and everyone there will either freeze or roast, depending on which way it goes.
Well, the main concern would be radiation. Also because it is tidally locked, it means that whatever core it may have is likely not spinning either. The fact that the Earth has a molten iron core which rotates faster than the crust, creating a strong magnetic field, which protects us from all sorts of background radiation and solar radiation. Unless the atmosphere is significantly thicker (which is a possibility) and has the right sort of gasses, it maybe of more concern than fluctuations in the habitable zone (if we can travel 20 light years in a short amount of time, I imagine we'd be able figure out a way to deal with the planet's other conditions.
Specifics on Gliese 581:
Mass 0.31[5] M☉
Radius 0.29[2] R☉
Surface gravity (log g) 4.92±0.10[6]
Luminosity (bolometric) 0.013[2] L☉
Temperature 3,480 ± 48[6] K
Metallicity [M/H] = −0.33 ± 0.12[6]
Age 7 to 11[5][7] Gyr
And:
In 1994 Edward Weis concluded that Gl 581, like half the 43 dwarf M stars he studied over a multi-year period, showed long term variability (and page 1137, Fig 1 shows Gl 581 had magnitude 10.58 in 1982 and between 10.57 and 10.56 from 1985 to 1990).[27] Bonfils noted in 2005 that "Gl 581 has been classified as a variable star (HO Lib), but its variability (Weis 1994) is only marginally significant. If real it would be on a time scale of several years, with short term variability being at most ∼0.006 mag."[28] Measurements by MOST showed short term variability of about 5 mmag (half a percent) over a period of a few weeks.
I'm not entirely certain what the second cut and paste means, but if I have some grasp on it, it's about as stable as the sun, just smaller and older.
You don't need the magnetic field to block radiation, even in interplanetary space the radiation level is barely high enough to be dangerous (can't find the specific level, but NASA was running rat tests to see if they could actually cause problems or not with the radiation levels involved), standing on a planet cuts it in half (less whatever the local rocks put out) and an atmosphere (which is the biggest part of Earth's shield) drops it even farther.
IIRC a magnetic field is important in limiting atmosphere loss from solar wind, but weaker solar winds or increased vulcanism would balance that.
Quote from: Requia ☣ on October 02, 2010, 08:25:18 AM
You don't need the magnetic field to block radiation, even in interplanetary space the radiation level is barely high enough to be dangerous (can't find the specific level, but NASA was running rat tests to see if they could actually cause problems or not with the radiation levels involved), standing on a planet cuts it in half (less whatever the local rocks put out) and an atmosphere (which is the biggest part of Earth's shield) drops it even farther.
IIRC a magnetic field is important in limiting atmosphere loss from solar wind, but weaker solar winds or increased vulcanism would balance that.
Your specifics are what I was thinking of- the thought just kinda jumped from point a to c.
Venus and Mars are good examples on either extreme- Mars' atmosphere was mostly stripped off because it lost core activity and vulcanism, even though it is further away from the sun and rotates at almost the same rate as Earth.
Venus is closer and rotates slower than the Earth, but maintains its atmosphere at very dense levels due to a highly active core, even though it is closer in size, but slightly smaller than Earth.
Actually, Venus could be a good example of how temperatures on Gliese 581 g might be more stable than we think- it's a little larger than Earth and would have a denser atmosphere resulting from extra gravity- if it has a other appropriate factors, the night time side might not be that cold, and the day time side might not be too hot. Naturally, we would have to study more either way, and feasible interstellar travel would help, since we only have 4 examples here that don't necessarily help us figure out all the needed factors for maintaining an atmosphere with stable temperatures.
If we do manage to detect such an atmosphere on Gl 581 g, we still probably wouldn't know much about its core activity. We could assume it's very active, but perhaps there could be some other factor at play.
I think that sleepiness is clouding my thoughts
Quote from: Doktor Blight on October 02, 2010, 02:32:43 AM
Quote from: Doktor Howl on October 02, 2010, 02:30:32 AM
Quote from: Mistress Freeky, HRN on October 02, 2010, 02:21:38 AM
Quote from: Doktor Howl on October 02, 2010, 02:19:36 AM
Quote from: Doktor Blight on October 02, 2010, 02:18:27 AM
Would you like some blankets?
We have this lovely "fire water".
Of course, it's equally likely that they'll do it to us. We'd have no way of knowing if a ship was on its way here until they started to slow down.
At first I thought this was the coolest thing ever, and it could be like Star Trek.
And then I realized. There are humans on this planet. And then I had a sad. :cry:
There is no reason to believe that aliens will be any more advanced or civilized than we are.
After all, keep Roswell in mind. They build the kind of ships that crash. We can do THAT.
That only happened because the helmsman was their equivalent of Welsh.
'
GOD FUCKING DAMMIT :crankey:
It is because they are anthropologists from the future.
Quote from: Requia ☣ on October 02, 2010, 08:25:18 AM
You don't need the magnetic field to block radiation, even in interplanetary space the radiation level is barely high enough to be dangerous (can't find the specific level, but NASA was running rat tests to see if they could actually cause problems or not with the radiation levels involved), standing on a planet cuts it in half (less whatever the local rocks put out) and an atmosphere (which is the biggest part of Earth's shield) drops it even farther.
IIRC a magnetic field is important in limiting atmosphere loss from solar wind, but weaker solar winds or increased vulcanism would balance that.
This is patently bullshit.
QuoteHi Dr. Stern:
I hope you can help me. I was just checking out your webpage and a question regarding the earth's Van Allen belts and solar flares/solar winds. I read that the earth's magnetic field has actually weakened by about 7% and field's actual total energy measured is less by 14% (since 1829). What is the impact of this weakening on the Van Allen Belts and the earth's Magnetosphere?
If solar flare activity increases (e.g. second-biggest geomagnetic storm ever measured hit the earth about a week ago) and the earth's magnetic field weakens, what impacts would we observe inside the atmosphere? Higher radiation exposure for folks on planes? Greater disruptions with electrical grids and radio transmissions? What's projected in the long term?
Can you recommend any websites that "a non-scientist lay person" might be able to read up on this. I guess the late August solar flare activity had nothing to do with the New York blackout (it occurred 2 weeks earlier in August).
Reply
When discussing risks and dangers from radiation in space, you should really distinguish two kinds of radiation:
(1) Trapped radiation, e.g. Van Allen Belt
(2) Energetic ions emitted by solar flares.
(1) Trapped radiation is governed by the geomagnetic field. If you are below the belt (as in the international space station) or elsewhere outside its intense part, you should have nothing to worry about. It could well be that the belt is now weaker than in the time of Gauss, 160 years ago, but that does not really change the preceding statement. These ions have about 50 MeV.
(2) Solar flares release unpredictable blasts of particles of higher energy, often 500 MeV and up to 10 GeV. In this case, people on the ground are still safe, because the atmosphere has enough thickness to stop the particles, equivalent to something like 4 meters of concrete. See the end of
http://www.phy6.org/Education/wsolpart.html
If you are in a spacecraft on your way to Mars, that can be dangerous. In Ben Bova's book "Mars" this does happen, and astronauts have to hide in a protected area--behind fuel tanks, probably.
On Earth, we have an additional shield, the Earth's magnetism, which will deflect all but the highest energies from regions at equatorial and middle latitudes. Jetliners crossing the polar region may perhaps find it useful to fly a little deeper in the atmosphere when the sun emits high-energy particles, and I heard the Concorde carried a radiation alarm.
The magnetic field would have completely protected the space station in its originally planned orbit, inclined 29 degrees to the equator (latitude of Cape Canaveral). As it happened, this was later increased to about twice as much, to enable Russian launch sites to resupply the station (which turned out quite important after the "Columbia" disaster). Twice each orbit, therefore, the station has relatively weak magnetic protection, near its closest approach to the magnetic poles. I heard a rumor that during the 3 big flare events at the end of October 2003 the astronauts did in fact hide, but that is strictly hearsay which I cannot confirm. The even bigger flare on November 4 did not produce such a radiation surge.
I am not sure about disruption of power grids, but I think it arises when the auroral electrojets shift to lower latitudes during storms. There are two large electric currents flowing along the auroral zone towards midnight, associated with the polar aurora (or more precisely, with the electric currents which produce big aurora; see in "Exploration of the Earth's Magnetosphere.") Like any electric currents, they produce a magnetic field which can be observed on the ground, and which changes fairly irregularly.
When they move equatorwards, into more inhabited regions (and out of them again), the changing magnetic field induces electric currents in the high voltage networks there. The induction is slow, so the transformers of the grid, configured to impede currents of 60 or 50 cycles/second, see essentially a DC current, to which they offer it no significant impedance, allowing it to grow big. Such a current can burn out transformers, unless appropriate circuit breakers are tripped in time. I don't know how serious that is: burn-outs happened in 1989, but as far as I know, not recently.
I am not an expert in disruption of radio. Flares emit X-rays, which modify the ionosphere, adding ionization deeper down. It then can absorb certain frequencies, but I am not sure whether, say, cell phones are affected, or ships and airplanes. I think the frequencies used by communication satellites are high enough to be immune, and of course a lot of land traffic these days uses optical cable. I am not sure about GPS.
That's about all I know on this subject. Let me know if you find anything more, or anything contrary to what I know.
http://www.iki.rssi.ru/mirrors/stern/Education/FAQs5.html#q72
http://www.iki.rssi.ru/mirrors/stern/Education/wms1.html
Good find Freeky!
The radiation (solar/ionic type stuff) might not be a problem for extremophile life. Gl 581 g, if it lacks sufficient geomagnetism, might have radiation loving microbes, maybe some lichen type stuff adapted to the situation, or :evil: a form of highly intelligent space roaches that will invade Earth to eat all our garbage.
Trying to find a downside there...
(http://i196.photobucket.com/albums/aa66/dracolupus/spaceroach.jpg)
Freeky: I've read that specific article before, note that it's talking about radiation *in space*, planetside radiation is much lower. Staying in orbit around a planet with no magnetic field would not be good (though if you already got to the planet, so your spacecraft must be capable of shielding), but planetside there are other shields. Hell MARS has enough atmosphere to prove adequate shielding.
Quote from: Requia ☣ on October 02, 2010, 06:45:05 PM
Freeky: I've read that specific article before, note that it's talking about radiation *in space*, planetside radiation is much lower. Staying in orbit around a planet with no magnetic field would not be good (though if you already got to the planet, so your spacecraft must be capable of shielding), but planetside there are other shields. Hell MARS has enough atmosphere to prove adequate shielding.
Sorry, I was reacting more to
Quoteeven in interplanetary space the radiation level is barely high enough to be dangerous
than the planetside bits.
Note that 'barely dangerous'; is not the same as not dangerous. A trip to mars wouldn't kill you right away, but there's an increased risk of cancer (as much as 19% in the high estimates, double a normal non smoker's chance of getting it).
Hmm, I did neglect to account for solar flares, I'm not sure how much radiation those put off, but it doesn't need to be a lot since it all hits at once.
QuoteA much worse problem is posed by very high-energy particles called cosmic rays. These will interact with metals and generate a storm of secondary radiation particles scattered out of the metal atoms. Thus, aluminum and other metal shields can themselves turn lethal when hit by cosmic rays. The only known way to stop cosmic rays safely is by providing a sufficient thickness of matter for them to be slowed down. This can be done either using water or soil. The thickness of water needed is only of the order of several centimeters. The thickness of soil (lunar or earth) needed is roughly six feet (2 meters). Exotic coatings and materials are being developed to serve as lighter shields, but however light these are, the cumulative mass needed to shield a practical human settlement is still enormous. Since these materials require advanced manufacturing processes, they will have to be manufactured on Earth and shipped out - at enormous launch cost.
http://www.adl.gatech.edu/research/tff/radiation_shield.html
Interesting.