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Tatooine's Double-Sunset a Common Sight
anthemaniac writes "Thirty years ago, Luke Skywalker beheld something that scientists are just now realizing is likely quite common in the universe: double sunsets. Astronomers have long known that binary star systems are common. And models suggested that planets could form in these systems, even though there's a double-tug of gravity on the material that would have to form a planet. Observations from NASA's Spitzer telescope, show that binary systems are just as likely to be surrounded by planet-forming debris disks are are lone stars."
Quantum systems also likely to be surrounded by debris.
"By the time they had diminished from 50 to 8, the other dwarves began to suspect 'Hungry.'" -Gary Larson
It is the FORCE of gravity, not tug. Not when you are talkin' about the Pod Race Capital of the universe. At a stretch you could call the Millenium Falcon a tug, but not what gravity exerts.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
cool but hot!
could be the human race is run...
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Any k-paxian could have told you this.
its common knowledge to them.
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How would the planet orbit them though?
Would it have to be far enough away so they appeared as one, or go into some crazy chaotic close orbit?
Luke didn't see the sunset thirty years ago - he saw it "A Long Long Time Ago (in a Galaxy Far Far Away)..."
I can't believe I'm posting to a Star Wars item...feel like I need to take a shower now.
http://memory-alpha.org/en/wiki/Risa
Planets may be common in binary systems, but what about planets that support life?
One of the reasons that Earth can support life is that the distance between the earth and the sun remains close to a constant for the duration of Earth's orbit around the sun, so the Earth receives a fairly constant amount of solar energy. This means, for example, that the temperature doesn't go down to -200 in the winter and up to +800 in the summer.
But in a binary system, I would imagine that orbits that provide a constant amount of solar energy in the Earth-normal range would be less likely to occur. (What would such an orbit look like when there are 2 suns?) Are there any astrophysicists out there that can comment on this?
Doug Moen
I have written a truly remarkable program which this sig is too small to contain.
So they have debris disks. That doesn't mean that planets are likely to coalesce. I'd guess the opposite, really, that proto-planets would tend to disintegrate under such conditions.
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Why do we have to drag the White House into every science discussion we have on SlashDot?
Solar dupe!
http://www.northernlatitude.com/images/FEB02-sundo g_parks_hwy.jpg
That is all.
Thank you. Drive through. (:wq)
Neat picture! Doesn't have anything to do with latitude, though; it's the ice crystals in the clouds. http://en.wikipedia.org/wiki/Sundog
In Hitchhikers Guide To The Galaxy, one of the planets had two suns & people would say, "Have a nice diurnal anomaly."
500 A.U. is more than 10 times the orbital radius of Pluto.
Remember the inverse square rule:
A companion star even 40 A.U. far out would be just an especially bright star. If it had the same luminosity as the Sun, it would appear 1/1600 as bright (.0625%).
The Tatooine scenario is still romantic fiction: Stars close enough to appear in the sky together as visible disks would probably be close enough that planets in orbit around them to have strange orbits.
IANAAP either, but a planet could perhaps stay in a Lagrangian point. That would ensure the stability of the trajectory and distance.
The Raven
...scientists have come to the conclusion that *that's* no moon.
if a binary system had two stars the size of our sun, then being far enough away for gravitational and seasonal stability would also mean being too far away for liquid water to exist. At least one star would have to be very large in a binary system for this to work.
Helliconia by Brian Aldiss had a striking ternary system with a small star (with an inhabited planet) orbiting a binary system, giving a 1,500-year long mega-season that gave it regularly-occuring ice-ages.
That seems quite viable, but it illustrates some of the extra threats to life in that situation. I would suspect that extra stars would lead to more planetary comet/asteroid collisions, owing to more variable gravity effects on outer-system objects like their Oort cloud.
that the additional gravitational pull of a second or third sun could contribute to a more vigorous tectonic activity level than would be present in a single star system, perhaps keeping the core of the planet(s) hot and this might keep the magnetic core active enough to preserve an atmosphere.
Maybe this would be more conducive to a life sustaining environment, even for planets further out from their sun than ours is. It's an old concept that a planet has to be just the right size, it's sun has to be just the right size and it must be a certain distance from that sun for life to rise and evolve.
I think there may be many exceptions to this rule. We are already beginning to seriously rethink our very own little solar system. I think we will soon conclude that life is VERY COMMON in the universe and maybe even in our own back yard.
At least I hope so.
One incredibly nerdish thing that always bugs me about Tatooine... how come you never see two shadows being cast on anything? Two suns == two shadows, right? I don't think that's ever been addressed in any of the re-releases.
Whatever, none of the "improvements" have done it for me anyways. In my day, Han shot first. And we liked it that way.
J
Mercury has a double sunset - with the same sun setting twice without going over the sky: http://www.time.com/time/magazine/article/0,9171,8 36746,00.html.
This was discovered sometime in 1967.
right, binary star systems no big deal and they could have planets. But those trinary systems, that's a whole different matter, every 22 years the habitable planets around them really, really suck. Unless you're a darkness loving carnivorous boogey-creature, then it's happy hour.
> Tatooine's Double-Sunset a Common Sight
Now all the fan boys need do is tell us why it took 20 years to build the Deathstar and why Luke found Leia such a "Turn-me-on Hot Chicky Mamma ooooh yeah", and their work will be complete.
http://www.chefelf.com/starwars/
According to Weird Al, it's two "longs" and one "far".
That's what NASA's Spitzer telescope found, okay...
But what about its Schwarzwenegger telescope - what'd it find?
Since when do models hang around with scientists, making up hypotheses left and right?
"...debris disks are are lone stars."
All is possible with the touch of his noodly appendage.
The first "sci-fi" reference for two suns that I can think of comes from the Hitchhiker's Guide to the Galaxy (keep in mind, I really don't know my sci-fi at all, so I expect there are others.)
Does anyone have an earlier reference? I suspect that Tatooine is a fairly recent reference, though popularly known it may be.
On those planets if you say to someone "shove it where the sun don't shine!", you will simply be met with looks of bewilderment.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
Everyone would be bisexual.
"Thirty years ago, Luke Skywalker ... "
..."
It was not thirty years ago, it was "A Long Time Ago in a Galaxy Far, Far Away
Anybody having played Elite and/or one of its sequel knows that for years...
Gravity is the result of warping space/time.
Most modern models have a particle, the graviton, exchanged between objects interacting gravitationally. In the Quantum and String Theory models, gravity is a real force, just much weaker (probably because space is warped in the fifth dimension, with gravity only being strong near its brane, and weak out in the bulk).
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