They can locate a planet 100 light years away but my GPS still wants to send me the wrong way up a one way street on my morning commute.
In images, it doesn’t look like much: just a blue dot against the black of space. What’s exciting about this little planet is that it has somehow manage to escape its star. Even getting an image of the object, dubbed CFBDSIR2149, is a pretty good trick: CFBDSIR2149 is only visible in the infrared, and then, only just (it …
"I think you meant Mondas from 'The Tenth Planet' [...]"
Aaargh, yes. Right story, wrong Cyber-planet. In my defense, I'm not old enough to have seen the broadcast and it's been decades since I read the novelization.
Getting my coat because clearly my anorak privileges will be suspended.
Blish (who is completely out of favour as an SF writer - too intellectual) pointed out that drives which manipulate gravity or space need not be attached to a vehicle - they can just be attached to anything that you want to move. His "Cities in Flight" series describes whole commercial cities which specialise in specific services - often mining or refining - traveling the galaxy looking for work.
At one point a small planet is provided with propulsion in this way. Perhaps.....
(a) The planet originally developed around the star, but was torn loose due to gravitational interactions.
(b) It's a planet, why can't it have an atmosphere? If you mean why has it's atmosphere not frozen solid, well Jupiter emits more energy than it absorbs from the Sun due to gravitational contraction (it shrinks about 1 cm in radius per century).
There's also a grey zone between a wandering gas giant planet and a brown dwarf star. Jupiter emits more energy than it receives from Sol, because something (probably a very small amount of hydrogen fusion) is going on in its core.
"Torn loose by gravitational interactions" implies some sort of catastrophic interaction such as another star passing close to a solar system. That's not necessary. Any solar system with more than two bodies is stable only in a statistical sense. A 3,4, ... N body gravitationally bound system is chaotic, and it is always possible that what appears to be a stable orbit will in fact end up with one of the planets ceasing to be gravitationally bound to its sun.
You'll be unsurprised to know that the future of the solar system has been carefully modelled. Earth is safe for the next 200M years or so. Beyond that, we can't say. The observations aren't good enough to distinguish longer-term stability from its opposite. Such is the nature of a chaotic system. An unmeasurably small difference today may be the difference between earth remaining in orbit or not, 300M years hence. "Past performance may not be a reliable guide to future performance"!
Back to mini brown dwarfs or large wandering planets, it's possible that these might be the last habitable places after all the universe's stars have burned themselves out. Has anyone ever written a far-future SF story set on or within one?
(a) is just a naming convention. Doesn't fit neatly into any other category, exo-planet will do for the moment.
(b) atmsophere is dependent on the planet's own gravity and composition, only slightly affected by suns and neighbouring planets
What's really curious for me is the temperature of 430C - it's out in deep space and can't be absorbing heat from anywhere else, in fact even considering a thick pea-soup atmosphere it must be losing heat to it's surroundings, and must have been doing so for a loooooong time. So is it possible that it's producing energy through very low-level fusion only happening deep in the core?
"So is it possible that it's producing energy through very low-level fusion only happening deep in the core?"
Not necessary. It's even bigger than Jupiter and both Jupiter and Saturn produce more heat than they receive. The steady compression of all that mass + slow natural radioactive decay produce more than enough heat to reach a few hundred degrees.
"Not necessary. It's even bigger than Jupiter and both Jupiter and Saturn produce more heat than they receive."
True, but even so they're still bloody cold.
"The steady compression of all that mass + slow natural radioactive decay produce more than enough heat to reach a few hundred degrees."
There would have to be an unfeasible amount of radioactivity to heat a gass giant planet 7 times the mass of jupiter up to 430C given that the majority of its mass (if it is a gas giant) won't be made of anything radioactive. More than likely it is just gravitation compression as you said + residue heat from its formation.
According to NASA website, Jupiter's surface temperature is -145C. Core temperature is unknown but "may be about" 24,000 C. Also found this nugget on universetoday: "Jupiter would have to add about 80 times its current mass in order to become massive enough to ignite fusion"
Since this planet is 7 times Jupiter's mass likely no fusion, just compression, and if surface temp is around 400C, core most be rather hot enough to warrant a few beers
It's very young so its going to be generating a lot of internal heat as it compacts under gravity and then differentiates according to density. And we're talking about an enormous amount of energy - the Earth obtained something like 2.5 * 10^32J from compression and another 1 * 10^31J during the formation of the Core.
Sadly a missed opportunity for an update at the appropriate time.
(i.e. You could of had the big explosion in the first episode creating a big sucky worm hole type thing. The worm hole obviously slurps the moon to a random piece of space for adventures to occur and disappears. But then ,because it's a weird worm hole, it reappears, (maybe 50 minutes TV time later), and continues it's suckage. Gives the writers quite a lot of scope for random encounters, political infighting, and killing off of expensive characters/actors when needs must. )
The Enterprise Bridge view screen fills and when the 1701 is groaning trying to break away.
Of course, what would all that be without the pointed eyebrows and tha command "DEEFLEKTOR SHEELDS -- FULLLL INTENSITEEEE!" :-)
"DEFLEKTORS SAY THERE'S SOMETHING THERRR --- SENSORS SAY THERE'S NOTTT??? READINGS GO OFFFF MY SCAYUL!" (WNMHGB)
It's just a matter of definitions. It might avoid a lot of arguments if it were done by mass, with a planet being a body more massive than an asteroid and less massive than a brown dwarf star, and with precise numbers setting the boundaries.
Note, any object gravitationally bound to our galaxy is orbiting at least one star. If it's wandering in interstellar space, it may be orbiting many tens or even hundreds of millions of them.
It can only be a planet if its roughly spherical (big enough to collapse to a sphere under its own gravity) AND its significant enough of a mass in its own orbit to have (largely) cleared it of debris. (Hence Pluto and Ceres don't count).
So, an exoplanet wouldn't actually be a planet by this definition. Perhaps they'll have to come up with a formal definition of exoplanet vs. dwarf planet. The good news is no kiddies are going to have to memorize exoplanets so no-one much will have to car or notice.
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Notice how circumlocutious everyone has to be since the Pluto-not-a-planet-anymore triumph?
How much wear and tear would have been saved on a dozen thesauruses if they could have just said "planet" instead of obsessing over the fact it isn't in a discernible orbit and therefore cannot clear one out?
Well done, "scientists". Another leap forward.
I thought the same :-) Thankfully Startrek, larry Niven (and to a lesser extent university) helped out.
A full, solid, dyson sphere is 'considered' impossible by the current beard and elbow patch brigade. Largely due to the amount of building material required given a nominal 1 au radius. However, given that four hundred years ago a cig lighter would have earned you a swift burning for withcraft, who knows what could be possible? I would suggest considering the amount of energy required to fabricate a sphere (as opposed to a net or swarm) by converting energy to matter plus propulsion requirements vs the amount of energy harvested would be the best way to work out if an advanced race would do it. Just because we cannot do it doesn't mean it cannot be done. Seriously, in 1000 years whos to say we cannot build a giant centre parcs around sol? One big discovery could be all it takes. Perhaps if the beards spent a little less time ranting at each other about exactly what is a planet and a little more time on original thought we might get there a little quicker!
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