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Ocean Planets on the Brink of Detection
Posted by
Zonk
on Fri Feb 02, 2007 04:28 PM
from the look-for-mon-cal-first dept.
from the look-for-mon-cal-first dept.
ZonkerWilliam writes "It seems, at least theoretically, that there may be 'ocean planets' out there in the galaxy. If there are, we are closer than ever to detecting them. The formation of such planets is fairly likely, reports the PhysOrg article, despite the lack of an obvious example in our own solar system. We may have a former ocean planetoid in the neighborhood, orbiting the planet Jupiter: the moon Europa. These water worlds are the result of system formation castoffs, gas giant wannabes that never grew large enough. If any of these intriguing object exist nearby, the recently launched CoRoT satellite will be the device we use to see it. The article explains some of the science behind 'ocean worlds', as well as the new technology we'll use to find them."
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Jupiter's Little White Spot Turns Red 105 comments
Feelyat writes "NASA is reporting that a small storm that formed on Jupiter last year has changed color from white to red. According to an article in Yahoo News, scientist Amy Simon-Miller speculates that the storm might have gained strength as it decreased in size, similar to how 'spinning ice skaters go faster when they move their arms closer.' She says that the storm has probably 'picked up red material from lower in the Jupiter atmosphere, most likely some form of sulfur which turns red as part of a chemical reaction ...' Well, we might be one planet down, but our Solar System can still surprise."
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On these planets (Score:5, Funny)
Re: (Score:2, Funny)
Re:On these planets (Score:5, Insightful)
In this particular speech, he meant to say that where there's water, there's oxygen to be extracted. In this, he's quite correct. It would take a significant amount of energy, but it's perfectly feasible to extract breathable oxygen from water on Mars.
It's just the way he put it that's outright hilareous.
Parent
Re:On these planets (Score:4, Funny)
WENSLEYDALE: Finest in the district, sir.
MOUSEBENDER: Explain the logic underlying that conclusion, please.
WENSLEYDALE: Well, it's so clean, sir.
MOUSEBENDER: It's certainly uncontaminated by cheese.
Parent
Re: (Score:3, Funny)
Re:On these planets (Score:5, Funny)
You say that like it's a bad thing.
Parent
Just the facts (Score:5, Funny)
Nice to start the summary off with not just one, but *two* tautologies!
Re:Just the facts (Score:4, Funny)
Yeah, but the failed to mention that every day we move closer toward the future!
Parent
Pilotless airplane! (Score:3, Funny)
(sorry can't hear the word tautology without thinking about that guy)
Re:Just the facts (Score:4, Funny)
Parent
Re: (Score:3, Insightful)
For all our sake... (Score:2, Funny)
I really hope they don't find any of them. If they do, we'll have hundreds of water world remakes and the level of pain that would bring is too much to bare.
Re: (Score:2)
Nitpick (Score:2, Insightful)
I know it's a nitpick, but of course we're closer than ever to detecting them. Guess what, we're closer to detecting them now than when you began reading this reply (by a couple seconds, but still closer).
Re: (Score:2)
Of course, this all assumes that the terms "closer" and "further" are being used to measure a temporal distance. If I'm looking for my keys, I could have been closest (physically) to finding them this morning when I was in the kitchen where they're under the newspaper, even though in only a few minute
A better name for the craft... (Score:2, Funny)
Of course, on said ocean planets inhabited by cetaceans one could exclaim:
"Admiral, there be whales here."
Ackbar said it best (Score:2)
Or more likely, "It's a trap"
Re: (Score:2)
The Good News... (Score:4, Funny)
Re:The Good News... (Score:4, Informative)
The projected maximum rise in sea level due to total melting of glaciers is around 80m. [usgs.gov] The average elevation of exposed land is about 2870m, [ilstu.edu] which is about 35 times as high. Melting everything won't inundate the globe, but it will require relocation from low-lying areas.
Parent
hm (Score:5, Funny)
No ocean planets in our own solar system... (Score:5, Funny)
Re: (Score:2, Informative)
Re: (Score:3, Funny)
Re:No ocean planets in our own solar system... (Score:5, Interesting)
What if that impact had never occurred? The Earths surface would be level, like the other terrestrial planets, and instead of the water settling into the lower basins (the oceans), it would cover the entire surface of the planet to a depth of several kilometers. Only a few of today's highest peaks would extend above that water level. Those peaks, in all likelihood, wouldn't exist either. Not only would the tectonics needed for their formation be absent, but a world without continents would have monster surface waves and erosion would scrub them below the waterline in a few million years. If there were ANY life here, it would be no more advanced than the fish which exist today.
Unfortunately, if we DO ever get out into space and find "Earth-like" planets of comparable mass and temperature, they will probably be water-bound just as the Earth would have been.
Parent
Re:No ocean planets in our own solar system... (Score:4, Informative)
So why no magnetic field? No convection. Why no convection? Two possibilities. 1) The lack of tidal stresses from a comparatively large moon permitted its mantle to largely solidify already, as happened on Mars. 2) On the other hand, the LACK of tectonics may have deprived the core of a way to vent excess heat. Convection happens on Earth because the top of the mantle is cooler than the bottom, and the top is cooler BECAUSE it can let off heat through tectonics. It's a self perpetuating process. With Venus, the lack of tectonics deprived the mantle of any heat release sources other than volcanism. This would permit the Venusian mantle to get much hotter than the mantle on our own planet. The increased heat without outlet would lead to a mantle far more uniform in temperature...and a mantle that is uniformly hot will have no convection.
So it becomes a self-perpetuating cycle. Something fractured the early crust of our planet, permitting subduction. Subduction and tectonics in general introduced temperature irregularities into our mantle, which kicked off convection. Convection then drove tectonic activities by itself.
A protoplanet under bombardment would have a fairly consistent mantle temperature once bombardment began to ease. Energy imparted from impacts would spread throughout the body, and cooling would occur uniformly at the outer edges of the planet where the molten material came into contact with space. The planet would then begin cooling from the outside in, resulting in a relatively uniform crust. Again, you merely need to look at all of the other terrestrial bodies in our own solar system to confirm the model.
It appears that something "else" is required to kickstart plate tectonics. The only really major thing we can identify, that fits the models, is our moon. The giant impactor which blasted lunar material away from the Earth disrupted the mantles temperature and blasted away a signifigant portion of the lighter material which should have formed our crust. The glancing blow which the models suggest would have been required for the Giant Impactor theory would have also left the side of the planet opposite the impact relatively unscathed (aside from the many millenia of debris impacts which certainly followed). As an added bonus, the newly formed moon around the planet, comparatively large and in a tight orbit, would have induced tidal forces which helped (and still help today) to keep the mantle moving.
No impact = No giant moon, no disruption of the even cooling of the surface, no disruption of the mantle, no convection, and no tectonics. Geologically, the Earth would be Venus, only covered in 1-2 kilometers of water and with a more temperate atmospheric blanket (it would probably be a far colder planet than it is today). Aside from a volcanic island or two, the planet would be a big orbiting ball of water.
Parent
Let's colonize these worlds! (Score:2)
Was predicted a while ago (Score:5, Funny)
Look under the section "Water: The Raw Material of Creation" *tranquilizers recommended* http://creationresearch.org/crsq/articles/21/21_3
(Please be sure to actually read is before axing my karma.)
The "God Ratio" (Score:2)
The way I thought about it was:
Heat(scale? strength?)of Star vs Mass of Planet vs Distance from Star
I called it the God Ratio in a tongue-in-cheek sort of way. I have no idea what calculations I was playing with and was way off of any "real" science about it, but the basic gist is the same.
Re: (Score:2)
Re: (Score:2)
All these worlds are yours except Europa. (Score:5, Funny)
Attempt no landings there.
First Glance (Score:3, Funny)
"Ocean Planets on the Brink of Destruction"
Oh my... were screwing up those too huh?
World (Score:3, Funny)
Then I can picture us attacking that world, 'cause they'd never suspect it.
They are on the way to detection. (Score:3, Funny)
Find and complete Water World... (Score:2, Funny)
What about desert planets? (Score:4, Funny)
Wil
NASA Simulator for a water world (Score:4, Informative)
It is a very general GCM so included in the download are paleo-earth configurations. You can run a simulation of the earth from 750 million years ago [columbia.edu] when it was mostly covered in water (but also very cold) to see one possible scenario. As mentioned above, you can add CO2 and turn up or down the sun or any other GHG to see other scenarios.
Disclaimer: I'm the project developer.
The real breakthrough is resolving power (Score:3, Insightful)
The real breakthrough is when we finally have enough magnification and resolving power to see living things on other planets. The great barrier reef is a living thing that can be resolved from beyond Mars orbit with today's technology. The first extrasolar life we see is going to be something like a great barrier reef.
The trick is going to be making a telescope the size of the solar system. The mission is probably going to use 2 Hubble size telescopes on opposite sides of Mars orbit, with incredible magnification well beyond the diffraction limit of each telescope, and the highly diffracted images from both telescopes being combined in software to produce a corrected image with a virtual aperture the size of Mars orbit. Only with that kind of mission are you going to "detect" habitable, extrasolar planets.
Re: (Score:3, Informative)
The Earth is a very large lump of iron and rock with just enough water for a few puddles to thinly cover 2/3 of its surface. The article is talking about whole planets composed almost entirely of water. Think of a bunch of melted comets that got smooshed together.
Re: (Score:3, Informative)
Earth is called a "water world" because it has a hydrosphere, though. The presence of water on a planet is by no means unique (Europa, Mars, most of the asteroids in our solar system), but the presence of water in abundance in the star's green zone hasn't been seen anywhere else. Earth is the only planet in the solar system where the *surface* temperatu
Nothing like Water World, here's why: (Score:5, Funny)
No, allow me to explain:
These things have to weigh less than 10 times what the Earth weighs, or they will become gas giants. Our sun weighs 332,946 times as much as the Earth. Only objects weighing at least three times as much as our Sun can turn into black holes. Only a black hole can suck as hard as Water World. Therefore, these water planets are nothing like Water World.
Parent
Re:Nothing like Water World, here's why: (Score:4, Funny)
How does one "weigh" a planet or star? Where do you put the scale?
Parent
Re: (Score:2)
Time to get my geek on. (Score:5, Informative)
Acceleration due to gravity is calculated as follows:
a = G * (m / r^2)
Since we're looking for the Sun's mass, we solve this equation for m.
m = (a * r^2) / G
The first thing we need to figure out is the value of a, or how fast things accelerate toward the sun. The earth is 1.5e11 meters from the sun, and travels in a (roughly) circular orbit once every 365.25 days (or 3.16e7 seconds). If you calculate the circumferance of the earth's orbit given the radius, you get 9.42e11 meters. The earth is moving at roughly 2.98e4 meters per second.
The next step is to figure out how far the earth falls toward the sun every second. We can do this (again, roughly) without using calculus. Let's say that, for one second, the earth continues to travel in a straight line instead of a circle. If you subtract the earth's real orbital radius from this hypothetical one, you end up with the number of meters that earth falls every second, or a. Note that this isn't an exact calculation -- I would need to use calculus to do that -- but it's still "close enough". I'm an engineer, not a scientist, so be happy I used 3.14 for pi, as opposed to "about 3."
The earth's new distance from the sun, if it travelled at a tangent for sone second, would be calculated using the Pythagorean Theorum, as follows:
d = sqrt(1.5e11 ^ 2 + 2.98e4 ^ 2) = sqrt(2.25e22 + 8.88e8) = 150000000000.00296
Subtracting the original distance from the sun, the earth has fallen about 2.96 millimeters in one second, which means that the earth is accelerating toward the sun at
m = 0.00592 * 1.5e11^2 / G
According to Google calculator:
((0.00592 (m / (s^2))) * (1.5e11^2) (m^2)) / gravitational constant = 1.9961037 × 10e30 kilograms
Now, looking up the mass of the sun:
mass of the sun = 1.98892 × 10e30 kilograms
Voila, I've just calculated the mass of the sun with less than 1% error, and I didn't even need to remember any calculus.
Parent
Re: (Score:3, Funny)
Re:Nothing like Water World, here's why: (Score:5, Funny)
Parent
Re: (Score:3, Funny)
Just borrow Archimedes' Lever.
Re: (Score:3, Interesting)
I know you were just making a joke (btw good one) but objects of any size can become black holes, including individual protons.
Re:Nothing like Water World, here's why: (Score:4, Informative)
No, he's referring to the Tolman-Oppenheimer-Volkoff limit - a neutron star above 3 solar masses will collapse to a black hole (or possibly a quark star), similar to Chandrasekhar's limit (about 1.44 solar masses) for forming a white dwarf. (Although because large stars blow off matter as they go through the changes, the starting mass for the star has to be better than about 8 solar masses.)
A proton couldn't become a black hole, its Schwarzschild radius is far less than a Planck length. It's generally considered that the smallest mass that can become a black hole (radius equal to the Planck length) is about 21.77 micrograms, called the Planck mass.
Parent