The Glade 4.0

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http://www.abc.net.au/news/stories/2011 ... 219037.htm

New planet found in Goldilocks zone

Updated May 17, 2011 12:47:00
A model of temperate surface for planet Gliese 581d

A model shows the possible surface temperatures of planet Gliese 581d, located around 20 light years from Earth. (AFP: CNRS)

French scientists claim to have found the first planet outside our solar system with the potential to support Earth-like life.

Modelling of planet Gliese 581d shows it has the potential to be warm and wet enough to nurture Earth-like life, they said.

It orbits a red dwarf star called Gliese 581, located around 20 light years from Earth, which makes it one of our closest neighbours.

Gliese 581d orbits on the outer fringes of the star's Goldilocks zone, where it is not so hot that water boils away, nor so cold that water is perpetually frozen.

Instead, the temperature is just right for water to exist in liquid form.

"With a dense carbon dioxide atmosphere - a likely scenario on such a large planet - the climate of Gliese 581d is not only stable against collapse but warm enough to have oceans, clouds and rainfall," France's National Centre for Scientific Research (CNRS) said in a press release.

For budding travellers, though, Gliese 581d would "still be a pretty strange place to visit", CNRS said.

"The denser air and thick clouds would keep the surface in a perpetual murky red twilight, and its large mass means surface gravity would be around double that on Earth."

Getting to the planet would still require a sci-fi breakthrough in travel for earthlings.

A spaceship travelling close to light speed would take more than 20 years to get there, while our present rocket technology would take 300,000 years.

More than 500 exoplanets orbiting other stars have been recorded since 1995, detected mostly by a tiny wobble in stellar light.

They are named after their star and listed alphabetically in order of discovery.

Big interest

Until now, the big interest in Gliese 581's roster of planets focused on Gliese 581g.

It leapt into the headlines last year as "Zarmina's World", after its observers announced it had roughly the same mass as Earth and was also close to the Goldilocks zone.

But that discovery has since been discounted by many. Indeed, some experts suspect Gliese 581g may not even exist but was simply a hiccup in starlight.

Its big brother, Gliese 581d, has a mass at least seven times that of Earth and is about twice our planet's size, according to the new study, which appears in British publication The Astrophysical Journal Letters.

The planet, spotted in 2007, had initially been dismissed as a candidate in the hunt for life.

It receives less than a third of the solar radiation Earth gets and may be tidally locked, meaning that one side of it always faces the sun, which would give it permanent dayside and nightside.

But the new model, devised by CNRS climate scientists Robin Wordsworth, Francois Forget and colleagues, showed surprising potential.

Its atmosphere would store heat well thanks to its dense CO2, a greenhouse gas, while the red light from the star would also penetrate the atmosphere and warm the surface.

"In all cases, the temperatures allow for the presence of liquid water on the surface," the researchers said

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"...but there exists also in the human heart a depraved taste for equality, which impels the weak to attempt to lower the powerful to their own level and reduces men to prefer equality in slavery to inequality with freedom." - De Tocqueville

The idea that we have the technology to tell the surface temperature and composition of a planet 20 light years away, but still can't find a cure for cancer is something I just can't seem to wrap my tiny brain around.

The French are really passionate about their lines of retreat...

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I'm no expert but I bet the cure for cancer is almost as complex as the cure for old age.

Better get going...

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I prefer to think of them as "Fighting evil in another dimension"

A planet stands still, the distance does not change to the point where it’s clinically significant.

Cancer on the other hand has too many variables to have an easy answer.

The cause of cancer is different between the types of cancer. E.g. cervical cancer are virus related where as breast cancer is more genetic related, while lung cancer is more lifestyle related, etc, etc, etc.

Cancer is also DNA dependent, while they carry some similar markers for the areas they are specific in. e.g. Cervical or breast. They deviate quite a bit from one another and is clinically significant. There are new genetic drugs been developed to combat this problem. Downside of course is how to produce these drugs without the price tag of a british castle.

I’m sure in the coming years, we’ll be able to find cure for some cancer, while still baffled about others.

Not to mention the fact thqt cancerous cells arehuman cells, meaning that anything you develop to kill them will kill any other tissues, unlike things targeting viruses or bacteria or parasites.

Additionally, no two cancers are really the same, as they originate from a combination of random genetic mutations reaching a critical mass.

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Darksiege: You are not a god damned vulcan homie.

LadyKate, not that I take Mr. Beck seriously, but the story he tells seems to repeat what I've read elsewhere.

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The U. S. Constitution doesn't guarantee happiness, only the pursuit of it. You have to catch up with it yourself. B. Franklin

"A mind needs books like a sword needs a whetstone." -- Tyrion Lannister, A Game of Thrones

Judging surface temperature of a planet is actually a fairly simple process. You just need to know how big and what type of star it is, and what distance a planet is from it. That will tell you how much energy from that star is reaching the planet, and from that temperature can easily be figured. As for composition, it's mostly just educated guesses. The article states that the planet is large enough that it could have a carbon dioxide atmosphere, not that it actually has one.

Really the only thing we can tell about these exoplanets is about how big they are and about what temperature they would "normally" be at. Venus is an example of a planet that is far higher temperature than these formulas would be able to account for.

I also find the fact that because this planet is in the appropriate temperature zone, people are throwing out that it's supposedly habitable. Ignoring the all the other things that could be wrong with it. Venus and Mars would both be habitable if they had similar atmospheres to Earth, are you ready to jump on a spacecraft and move to one of them?

It's interesting then how we landed people on the moon before we could find the surface temperature of habitable planets in other star systems.

http://en.wikipedia.org/wiki/Spectroscopic_analysis

Every type of material in the universe has a unique "fingerprint" in the spectrum of electromagnetic energy that it radiates. By reading these color spectrums and comparing them to known materials, we are able to determine what elements are present in an object. We've been able to do this for well over a hundred years. Great distances simply means we have to take things like Doppler shifting into account, and need more sensitive instruments to detect wavelengths of electromagnetic radiation. It doesn't hurt that electrodynamics is currently our most precise field of science.

We have been studying the stars for thousands of years. A quick search on wikipedia reveals that the first documented discovery of a cause for cancer was in 1775. By this point, astronomy already had a robust mathematical foundation, and we were aware that Mercury's orbit did not fit in with Isaac Newton's predictions.

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Buckle your pants or they might fall down.

The moon is closer and thus much easier to assess the composition of. Especially since .. ya know.. it's made up of a lot of the same stuff on earth... just without enough gravity to pull in it's own ozone and stuff.

Plus it only takes a couple of days to get to the moon... so... why not?

you are more likely to knock on a neighbour girl's door to figure out how hot she was, than driving to the other side of the world to figure out how hot a girl was. You'd want some proof she was hot before you started driving.

Ah, see, we need sensitive instruments. This only requires a society full of millions of people from all fields working hard for decades.

The moon landing was a hoax.

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Ron Paul 2012

I don't find it all that surprising.

Astronomy had a serious head start on medicine.

Our earliest cultures were star-gazing. Cancer wasn't even noticed/identified until a couple hundred BC.

The microscope beat the telescope by a couple decades, but that didn't stop it from being another hundred and twenty years before cells were discovered. The difference between stars and planets was discovered much more quickly.

And on, and on.

Edit: Bah. Serves me right for not reading the rest of the thread. Corolinth already posted similarly.

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"Aaaah! Emotions are weird!" - Amdee
"... Mirrorshades prevent the forces of normalcy from realizing that one is crazed and possibly dangerous. They are the symbol of the sun-staring visionary, the biker, the rocker, the policeman, and similar outlaws." - Bruce Sterling, preface to Mirrorshades

Telling temperature of planet is about as easy as getting a sample of light from the planet and the star and if it were possible...just from the planet.

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"...but there exists also in the human heart a depraved taste for equality, which impels the weak to attempt to lower the powerful to their own level and reduces men to prefer equality in slavery to inequality with freedom." - De Tocqueville

Thank you for the science lessons, peoples. That does make more sense now.

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"Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own." Jesus of Nazareth

This is I think the most interesting way I've heard to test out moving to the moon.

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"None is more important, none more legitimate, than that of rendering the people safe as they are the
ultimate guardians of their own liberty."- Thomas Jefferson

"Yeah, I'm rehearsing my poker face. I don't handle stupid well. *sigh*" - Farsky

Plus, Lydiaa is a tease. You can't drive from here to Australia.

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Well Ali Baba had them forty thieves, Scheherezade had a thousand tales
But master you in luck 'cause up your sleeves you got a brand of magic never fails...
...Mister Aladdin, sir, What will your pleasure be?
Let me take your order, Jot it down -You ain't never had a friend like me
█ ♣ █

I also don't want to be crushed under the weight of my own hair.

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"...the line dividing good and evil cuts through the heart of every human being. And who is willing to destroy a piece of his own heart?" -Aleksandr Solzhenitsyn

I'm not sure exactly how it works for planets, but stars can typically be classified rather easily by their color. The color that the star appears when viewed (this is different from line spectrum) gives an indication of how hot it's burning, just as the color of a flame indicates the level of heat.

Heat radiating out of a planet could be measured in a similar fashion, though distance is a greater concern. This is how we determined the temperature of planets within our own Solar system.

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Buckle your pants or they might fall down.

Planets and stars are different though. You can't simply take an average spectrum of a planet and get an accurate temperature reading.

With a star, You can largely discount any reflective or external heat sources (unless we're talking about a close binary star in which case one star can heat part of the other--it can be factored out, but it makes it a LOT more complicated)
Stars you basically just map it against the scale for blackbody radiation to calculate temperature. But it isn't quite the same as total energy output. Size/Mass factor in as well.

Planets though, do not generate vast amounts of heat on their own. You cannot use their average spectrum vs. Expected blackbody values to get the surface temperature. Planets generate very little of their own heat, far far more of it is generated by the star and the rate of absorption is influenced by atmospheric composition, surface albedo, etc.


Simple version: a with theoretical perfect black object you can directly calculate temperature by looking at the average spectrum of the light it puts out--effectively, its color. Stars get 'close enough for jazz' to use this as an estimation of their surface temperature. But imagine a perfect mirror next to that perfect black body. The mirror is reflecting ALL the energy it receives from the black body radiator--trying to get a temperature reading off of the mirror will be inaccurate.

This is further complicated by the fact that half of the planet is being heated and half of it is cooling at any given time since its only half in the light where as a star's entire surface is fairly uniform (yes, yes, I know there are massive fluctuations from things like sunspots, flares, etc)


http://en.wikipedia.org/wiki/Black_body_radiation

If we only used blackbody calculations of Earth we'd estimate the planet's average temperature at about -18 C. Other factors play into it, obviously (Atmospheric greenhouse effects etc)

I guess I assumed they used Thermal imaging.

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Not really possible Hopwin. Not like you're thinking. If we are detecting these extra-solar planets its often only because we're picking them up in one of a couple of ways:

a) Occlusion - how much they dim the star when they pass between us and the star.
b) gravitational 'wobble'


Really thats about it. There are very few stars we can even pick out as more than a single point-source of light.