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Coriolan
23-02-17, 07:19
Exoplanet discovery: seven Earth-sized worlds found orbiting nearby star

https://www.theguardian.com/science/2017/feb/22/thrilling-discovery-of-seven-earth-sized-planets-discovered-orbiting-trappist-1-star?CMP=Share_AndroidApp_Eupedia_Forum

Several of these planets are located at the right distance from their star to be inhabitable and have liquid water. That's exciting and scary at the same time.

bicicleur
23-02-17, 09:07
if they are tidaly locked, possibility to live there is very restricted

but maybe creatures on one of these planets already discovered earth and are planning to visit us ..

ngc598
23-02-17, 13:06
The data suggest that all the planets were already locked less than 100000 years after their building. We can assume that at least the inner five planets are rocky like the Earth, probably all of them (Frost line at 150-200K, that is 0.04-0.07 AU in that system). The densities and so their masses should be roughly the same as Venus and Earth then.

Tidal lock means getting hot on the day side and freezy cold at the night side. To avoid this they need a dense atmosphere, considerably denser than the Earth's. They have a magnetic field which is less then the Earth magnetic field with the bad habit that the less habitable inner planets (too hot) having greater values, which is good for protecting against radiation from the star, and the outer, more 'habitable' ones, have less protection. Conditions seem to be not very favourable, but there is still some possibility for life, depending on the amount of atmosphere and the age of the star. Red dwarfs tend to be pretty variable in luminosity, have a lot of flares and high x-ray and UV radiation up to a few billion years until they 'settle'.

The water content is another issue. In our solar system there is only one terrestrial planet out of four, which has plenty of it, all the others have practically nothing. Assuming that magnetic field (protection of molecule dissoziation) and temperature (protection against escape of water molecules) are the main factors to hold water on the planet, it'll be not very easy. More atmosphere means more greenhouse effect, means more temperature, so only the outer ones are cold enough to hold water. On the other hand they have probably not enough protection against dissoziation and therefore water will get lost as it occurred on Venus. Needs very special conditions to give at least one planet a good chance for life.

Yetos
26-02-17, 09:47
scary indeed,

to pass your hole life traveling with speed of light !!!!

no way :useless:

Angela
26-02-17, 18:12
I think it's actually more scary to believe we're alone in the universe.

@Yetos,
They'd have to be the kind of people who have no problem with very long tours of duty at sea without putting into port, or like submariners perhaps.

Some people can't stand it. My husband went on only one cruise. Even though the ship docked every other day he couldn't stand it. It wasn't just sea sickness; he said it was knowing that he couldn't get off the damn thing. He used to stroll and run on the jogging course at the top level of the ship. Personally, I think it's part of control issues. The same kind of people usually don't like to fly. I'm perfectly happy doing either. . Must be all those seamen genes. :)

Yetos
28-02-17, 16:30
I think it's actually more scary to believe we're alone in the universe.

@Yetos,
They'd have to be the kind of people who have no problem with very long tours of duty at sea without putting into port, or like submariners perhaps.

Some people can't stand it. My husband went on only one cruise. Even though the ship docked every other day he couldn't stand it. It wasn't just sea sickness; he said it was knowing that he couldn't get off the damn thing. He used to stroll and run on the jogging course at the top level of the ship. Personally, I think it's part of control issues. The same kind of people usually don't like to fly. I'm perfectly happy doing either. . Must be all those seamen genes. :)

well I love boats and ships, cause I can run front and back and in and out and left side to right,
but I also hate plane flight cause I am stuck at a seat and i can not control a thing,
It is a feeling of prison.
I think men want to have control, and also freedom to escape.
my 'nightmare' is the dentist, especially if he is not explain what he is doing to my mouth.

Angela
28-02-17, 17:32
well I love boats and ships, cause I can run front and back and in and out and left side to right,
but I also hate plane flight cause I am stuck at a seat and i can not control a thing,
It is a feeling of prison.
I think men want to have control, and also freedom to escape.
my 'nightmare' is the dentist, especially if he is not explain what he is doing to my mouth.

It can also be claustrophobia in some people. I know a woman who has to get a seat right near the emergency door and still has to take two xanax to get through a trip on a plane. She's also a pretty controlling person, though. I seem to attract them. :)

I do think it's pretty primal for some people. Do you always have to be the one driving? That's another sign of always wanting to be in control. :)

About submariners, you have to go through prolonged psychological testing, because a lot of people just can't tolerate it. I think long periods of space travel would be most similar to that. There's also lots of physical effects even from just being on the space station, so somehow they'd have to find solutions for that, or people who have a unique set of genes which would enable them to not suffer as many consequences.

If we ever colonize such areas, those would be quite some founder effects, wouldn't they?

Curiocity
01-08-17, 17:03
So, when do we travel to a new earth? Wonder if interstellar travel could be real.