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Is Jupiter Earth's Cosmic Protector?
Hugh Pickens writes "Last Sunday, an object, probably a comet that nobody saw coming, plowed into Jupiter's colorful cloud tops, splashing up debris and leaving a black eye the size of the Pacific Ocean — the second time in 15 years that this had happened, after Comet Shoemaker-Levy 9 fell apart and its pieces crashed into Jupiter in 1994, leaving Earth-size marks that persisted up to a year. 'Better Jupiter than Earth,' say astronomers who think that part of what makes Earth such a nice place to live is that Jupiter acts as a gravitational shield, deflecting incoming space junk away from the inner solar system where it could do to humans what an asteroid apparently did for the dinosaurs 65 million years ago. 'If anything like that had hit the Earth it would have been curtains for us, so we can feel very happy that Jupiter is doing its vacuum-cleaner job and hoovering up all these large pieces before they come for us,' says Australian amateur astronomer Anthony Wesley, who first noticed the mark on Jupiter. But others say the warm and fuzzy image of the King of Planets as father-protector may not be entirely accurate. In 1770, Comet Lexell whizzed by the earth, missing us by a cosmic whisker after passing close to Jupiter. The comet made two passes around the Sun and in 1779 again passed very close to Jupiter, which then threw it back out of the solar system."
It's a bit like saying one speck of dust is protecting another speck of dust from other, smaller dust, as they swirl around an eddy of warm air in a coliseum.
Is Jupiter Earth's Cosmic Protector?
If this is true, it gives us another criteria to look for in distant solar systems that we suspect may harbor life or that we would like to colonize: a large shield planet in the same system capable of leaving the smaller world to develop uninterrupted.
It is interesting to wonder if our odds increase or decrease on being hit when there is a large massive body in our solar system. Like the article and summary say, some objects that would not have come close could be put on course for earth via Jupiter's gravitational forces. Who knows, maybe massive bodies like Jupiter pull more space debris into our system and make it more hostile than if it were just the earth orbiting the Sun?
My work here is dung.
Sorry for the dangling preposition in the subject, but regardless of whether or not Jupiter acts as a magnet for dangerous astral bodies, I wonder how risky it is to leave that job to Jupiter.
We have seatbelts in cars despite the mandatory brakes which are installed. We have random personal screenings at the airport even though we have a standardized process of metal detection and baggage scanning. We should not just sit idly without a comet/asteroid detection and elimination system just because Jupiter is catching the big ones for us.
We've been hit before. I don't want to get caught in the slamming door. How about some information, please!
... is the fact that eventually we have to get off earth and learn how to survive in the hostile universe anyway.
Think of a sphere whose radius as at the center of the sun and whose radius is at the center of Jupiter. Do you want to take a shot at how many orders of magnitude the inscribed area of Jupiter is to the entire sphere?
Do you want to take a shot at how weak Jupiter's gravitational field is? How about compared to the other gas giants? Within an order or two.
How about when Jupiter is in a phase of its orbit not anywhere "close" to the earth?
Now if Jupiter were like my boss, it would fling those comets at the earth with the message: "This issue is escalating rapidly. I need you to work on this today; send me status before you leave."
That Jupiter really sucks?
Yes, and so is the Moon, as its cratered far side will show you (the far side is much more cratered than the front side which shows how the Earth attracts asteroids towards the far side and away from the near side).
Next question?
You just got troll'd!
In astrology, Jupiter is considered the "greater benefic," the planet that bestows fortune, luck, and positive benefits.
Just sayin'.
"In 1770, Comet Lexell whizzed by the earth, missing us by a cosmic whisker after passing close to Jupiter. The comet made two passes around the Sun and in 1779 again passed very close to Jupiter, which then threw it back out of the solar system."
Better known as "the great snowball fight."
The Earth will eventually be wiped out, obviously. We can't get lucky forever.
We'd better spread outselves out.
The current STS-127/Expedition 20 mission has shown us that troubleshooting a malfunctioning urine-recycling toilet and a tripped circuit breaker on a carbon scrubbing unit are far easier to fix in LEO than out father, especially considering how critical both systems are to a more distant mission.
Up, Up, Down, Down, Left, Right, Left, Right, B, A, START
The Earth has not yet faced a galaxy coming straight at it.
This reminds me of that anti-tiger rock I keep in my sock drawer?
That rock is so good, damn tigers are dieing out in India. Maybe Jupiter has similar effect on galaxies?
Mit der Dummheit kämpfen Götter selbst vergebens
Is it actually more likely for a body to be directed away from Earth than to Earth by Jupiter? I mean, it seems that a body not destined for Earth could otherwise hit if affected by Jupiter's gravity sufficiently.
Jupiter is the only planet in our system close enough to the sun and with a deep enough gravity well for them to have a barycenter (common orbital center) outside the sun's surface. That sort of wobbly orbital mechanics has far more effect on trajectories of small bodies than a nice, neat set of concentric circular orbits. The sun-Jupiter system will be more likely to cause fluctuations that result in small interlopers to get thrown out of the system or sucked into one of their gravity wells. Seeing the result on Jupiter is rare. Seeing it at the sun is more common. Between the two they're going to suck up far more than hit elsewhere.
But their influence is only the majority of a chaotic multi-body system. Just because they account for the most hits doesn't mean they take them all and nothing gets through elsewhere. Of course some will miss the big guys and hit (or nearly so) some of the others. That's the nature of a chaotic system of orbital mechanics. They are not exerting influence in an intentional manner, rather a deterministic but fairly unpredictable manner.
To assume a certain thing always happens because it has happened, and also to say it not accurate because there is an exception, is the sort of low caliber absolutist thinking that's common in "modern" science reporting. I have no doubt the parties credited with these viewpoints understand quite well the situation, and the apparent controversy is a function of the author of TFA.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
I don't want to get caught in the slamming door. How about some information, please!
We have reason to believe that you have fallen a victim to weapons of psychological warfare.
For your own good, turn of your audio and video receiving devices as well as any audio or video player and go get some sleep.
Mit der Dummheit kämpfen Götter selbst vergebens
Why not correct your dangling preposition rather than apologize for it?
Claiming that Jupiter's purpose is our solar system's vacuum cleaner is preposterous.
Yes, it will catch more stuff due to its surface area but the volumes involved make Jupiter's influence negligible.
The subject line is limited to an insufficient number of characters.
"Is that something on which we should bet our existence?" is about 5 bytes too long.
He just had a bad day.
After realizing what he did, he flicked that comet as far away from Earth as possible. And he said he was sorry.
The comet was never seen again. Lexell, after conducting further work in cooperation with Pierre-Simon Laplace, argued that a subsequent interaction with Jupiter had further perturbed its orbit, either placing it too far from the Earth to be seen or perhaps ejecting it from the Solar System altogether.
Mit der Dummheit kämpfen Götter selbst vergebens
It makes me wonder if, over time, all that added gravitation might not start to degrade the orbit somewhat, to say nothing of a possible single large impact.
We have to get our eggs off this speck of dust.
I find it amazing and worrisome that an object that size can get so close to Earth and hit Jupiter without astronomers learning about it until after the fact. To me, it is an indication that current near-earth object surveillance systems are not worth much.
If the word logically doesn't offend you in that context. The largest temple in Rome was that of Jupiter Optimus Maximus on the Capitoline Hill (Wiki). So the Romans at least worshiped deities of some real world benefit.
/s
I think it's telling that most of the comments in the summary come from amateur astronomers.
Jonti Horner and BW Jones have written a series of papers on this, summarized in this Astronomy and Geophysics article The first paper deals with the Asteroids. The second, in press, considers the Centaurs The third, of perhaps most relevance to this discussion, considers the Oort Cloud objects.
(To simplify the simulations, Earth was inflated to one million times its actual size. A juicy target indeed)
With Shoemaker-Levy I could understand how Jupiter could catch a comet, but what I don't understand is that the comet subsequently can run into Jupiter. I mean, shouldn't it continue orbiting around Jupiter just like the other moons around Jupiter do?
Bert
This is the exact reason we need thermonuclear hydrogen bombs stationed in outer space, ready to shoot: Unlike the dinosaurs, we don't have to be sitting ducks, we have the ability to defend ourselves against incoming comets. The problem with stationing bombs in outer space is an issue of trust: people down here still haven't figured out how to live in peace and leave each other alone, the UN is still not a functioning body of world government, people still play the "I don't trust you, I'll kill you before you kill me"- game, and call it self defense. So there is a distinct possibility that bombs stationed in outer space are directed back at Earth by people who are mad at each other, and can't just take it like a man, or can't stop dishing it out so others have to take it like a man. Possibly the bombs could be stringed out and stationed very far, into solar orbit past Mars near the asteroid belt, and Earth could carry many layers of inner defense shields, that stop any stray bombs that are hijacked, with some finite reaction time still left. The good part about having the bombs(and their observatories) extremely far is that the farther the comet is deterred by a minute angle on its path, the less effort is needed. So the benefit to risk ratio is better, because a bomb hitting Earth would only cause a localized damage, compared to the same force being able to deter an object the size of our moon by that 1 degree on its path to just miss Earth. The downside of going very far, is that it's easy to have stringed out objects in a solar orbit in a plane, as a circle, but it's hard to cover a sphere, like GPS does, because the paths might cross, and minute gravitational fluctuation might cause some of the objects to collide. Maintaining very many bombs that are far, compared to the much fewer required that are very close is also an issue, especially from a hijacking standpoint. A few bombs hijacked and hitting Earth would cause a local catastrophy, but if all the bombs that are very far are hijacked simultaneously, and redirected to Earth, that could be worth than the problem they are meant to defend against. A possible best solution is having habitable outer space stations, http://en.wikipedia.org/wiki/O'Neill_cylinder, cylinders that provide artificial gravity on the inner surface by rotation/centrifugal force, and are built triple layered gradual vacuum against air diffusion/leaks, and extremely heavy walled to protect from outer space radiation to replace Earth's atmosphere (this means complete artificial lighting/farming/silicon solar panels, except a very few lead glass windows. In such case you don't keep all your eggs in one basket - whether there is a major asteroid hit, or a global nuclear war wiping out all life on the planet, we would still have people and plants and animals, we would still have Life to come back and reseed and repopulate the planet. Life would not die. Such space stations traveling to the region of Mars then could take on the job of watching for comets and taking care of them, and though there is a distinct possibility of interstellar war between such space stations, at least having the technology and ability to live in a space station in pure vacuum/cold/intense radiation, whether that space station is landed on Earth, under water in Earth's oceans, under the clouds of Venus, behind Jupiter, or far past Pluto running on nuclear fuel alone, each of these give Life and humanity a better chance to survive. All it takes is at least a few people to make it after a global catastrophy. The real danger is making robots smarter than us that hunt us down and exterminate us. Back in the old days there was such a thing as defense - walls, trenches, fortifications. These days, because of technology, the only defense is attack: the equilibrium of mutually assured destruction. Yes we did gain the ability to beat the odds that dinosaurs couldn't, but we also gain the ability to destroy all life within a few months. As technology progresses, our ability
The whole notion that some body that is on the other side of the sun from us half the time is protecting us doesn't really work in my mind. It seems that it only works if you imagine the universe is laid out on a line. Put the Sun at zero, the Earth at 3 and Jupiter at 10 and then anything heading your way from >11 has to get past Jupiter first. In reality we can't even rely on foreign objects coming in along the ecliptic.
We don't do that because the likelihood of somebody abusing the weapons to kill us is substantially higher than the risk of being killed by an impact. Further more you're assuming that we'd get it right, and let's face it we tend to be kind of hit or miss on things like that. We were able to more or less successfully fight the ozone layer problem, but pretty much completely refuse to do anything about global climate change.
I'm not sure what makes you so sure that there'll be much left by the time a space object becomes a risk or that we'll be able to spot it in the first place. Many of those meteors move pretty damn fast.
the earth has had several mass extinctions in the past, the most recent was 65.5 million years ago when it is believed a meteor impacted the earth causing the demise of the dinosaurs, there
there was a few others that may or may not been caused by cosmic impacts
Politics is Treachery, Religion is Brainwashing
i was under the impression that Jupiter was our protector, isn't that prevalent theory in science today? didn't Carl Sagan talk about this in Cosmos?
unless drugs have totally fried my brain- isn't Jupiter's mass (gravitational pull) what causes the huge asteroid field between Mars and Jupiter?
i had better dust off those Cosmos tapes and find my bong...
"You can kill the revolutionary, but you can't kill the revolution."-- Fred Hampton
It would be a lot more painful.
Eventually all comets, who run on an elliptic orbit around the sun and repeatedly cross the earth orbit have a good chance to hit us sooner or later, I suppose. If those comets also pass Jupiter regularily, there is surely a good chance that Jupiter throws them away or catches them, before they hit us.
On the other hand there is also a chance that Jupiter throws one or the other asteroid at us that was on an unproblematic orbit around the sun, before it came into the influence of Jupiters gravity. To decide if Jupiter is good or bad seems to be just comparing those risks/chances, like getting safed by jupiter from some comet that might hit us otherwise sooner or later or getting a big asteroid thrown at us due to Jupiters gravity.
So far, none of the cures for "Global Climate Change" are better than the problem.
It seems to me to be a fact that life would only get worse for me if we were to implement any of the more drastic solutions. As most everyone on the planet feels the same way, there's no logical reason to do anything.
The absolute worst possible outcome is that we consume all technologically-related resources and have to fall back on subsistence living. That's only a tragedy if you happen to be alive during the change.
Only a programmer well versed in orbital mechanics could make it "interesting." The average slashdot commenter apparently isn't.
see http://jontihorner.com/index.php?p=1_10_Publications> Horner, J., & Jones, B. W for the results of (non-brain-dead) modeling.
The absolute worst possible outcome is that we have made so many other species extinct by that time that there is no stable ecological niche for humans and we go extinct too. I'm not arguing that this is particularly likely, but it's definitely worse than your worst case, unless you were counting subsistence 'living' with population = 0. However, adding that to your list of consequences with a small probability (0.5% or so) shouldn't make any difference to you. In fact, adding it with a very large probability (99,99995% or so), given your 'logic', doesn't make any difference either, so carry on.
Just as a hint, real logic means, if you introduce different facts, you just might reason to a different result. Your real, if unstated 'logic' is 'If it's not me it hurts, it's not a tragedy'. Since you didn't state it openly, but a bunch of unconnected claims you call logic, you don't have to be concerned that someone would point out that you are a sociopath, using an entirely emotional argument to provide pseudo-justification for being a rat-bastard who has basically told every single person reading this you don't care if their loved ones and descendants live or die.
Who is John Cabal?
for the dinosaurs, they were dying out before it hit and others survived well beyond the collision. Moreover, one cannot state with certainty that a similar event might mean to humans. It would depend where it hit and the response. In some sense it might stop us from our dangerous current course where significant opinion welcomes easily seen disaster. Some blinded by myopic short term interests and others believing, at least some humans, are special and will be protected by their deity of choice. A cosmic event might cause some to rethink was is really important not just for themselves, but for the species. But perhaps not, the survivors may just believe some strayed enough that wholesale punishment has been inflicted upon nearly all. Therefore, their deity (and their's alone) must be placated.
If the latter becomes the predominant voice, at least we can be consoled the planet might not go the way of Venus.
I think I speak for all of us Jupiterian slashdotters when I say I have a problem with that statement.
Maybe. But I find a bit scary that nobody noticed in space the large "object" before it crashed into Jupiter.
Slashdot, fix the reply notifications... You won't get away with it...
Exactly how does "which then threw it back out of the solar system" disprove the theory?
There is also conjecture that earth's atmosphere was initially "seeded" by major cometary impacts, without which our kind of life could not have developed. So over the entire history of our planet, (if this is true) cometary impacts have not been completely negative from a human perspective.
when it happens daily, is it really news?
Do you even lift?
These aren't the 'roids you're looking for.
The whole "Jupiter shield" idea is myth. There's no reason to assume that Jupiter will throw more junk into wider orbits than into tighter ones more likely to hit the earth.
From the Wikipedia article on Jupiter (assuming it is correct): "Jupiter is 2.5 times more massive than all the other planets in our Solar System combined â" this is so massive that its barycenter with the Sun actually lies above the Sun's surface (1.068 solar radii from the Sun's center). Although this planet dwarfs the Earth (with a diameter 11 times as great) it is considerably less dense. Jupiter's volume is equal to 1,317 Earths, yet is only 318 times as massive." http://en.wikipedia.org/wiki/Jupiter Surface Area: 6.21796Ã--1010 km2 = 121.9 Earths So this would only make sense that it had a much greater surface area (122x) than earth to be hit or had a 122% better chance of getting smacked compared to our own.
Architectural Renderings
I'm just guessing that the sun does more garbage collection than Jupiter.
Wanted to type "dying", typed diing, spell checker corrected to dieing, didn't preview text myself...
It happens.
I remember once I mistyped "Queue" as "Que", to which someone replied "Que?"... we laughed... good times.
Mit der Dummheit kämpfen Götter selbst vergebens
TL;DR
There are several different energy gathering systems that we know how to operate in an energy positive manner (i.e., the energy output could be used to create an identical system+energy). This makes the complete consumption scenario rather unlikely.
Nerd rage is the funniest rage.
What about when we're between Jupiter and the sun? Then the pull from each would put us pretty much square in the path of whatever's coming, wouldn't it? No wonder people are so scared of syzygies.
The point is that not only does Jupiter protect the terrestrial planets now, but that Jupiter has protected Earth from the birth of the solar system. This is one reason that Earth isn't yet another gas giant.
The recent controversial redefinition of the word "planet" (http://en.wikipedia.org/wiki/IAU_definition_of_planet) discusses this "vacuum cleaner" effect as the third of three criteria:
Jupiter is by far the largest planet and has by far the largest such effect. A lot of the reasoning in the comments has caused one to question how well Astro 100 courses are being taught, but perhaps it is ok to venture one simple statement for why Jupiter preferentially protects the inner solar system. The comets that threaten us originate in the distant Oort Cloud (http://en.wikipedia.org/wiki/Oort_cloud). They visit the inner solar system, but their orbits all begin far outside. It is thought that external perturbations play a role in causing them to plunge inwards. Jupiter (to oversimplify outrageously) stands between us and the bombardment.
Fundamentally this is the famous "three body problem". The equations describing Newtonian gravity are straightforward to solve for two bodies, and impossible to solve precisely for three or more. Relativistic corrections add a bit of spice. As a result planetary mechanics requires numerical integration.
The solar system is full of neat resonances and points of stability such as the Lagrangian points. Jupiter's Trojan asteroids (http://en.wikipedia.org/wiki/Trojan_(astronomy)) cluster at L4 and L5 and are thought to be as numerous as those in the main belt. Our Moon's tidal locking is a) imperfect (since the orbit is rapidly growing (http://en.wikipedia.org/wiki/Moon#Orbit_and_relationship_to_Earth), and b) simple compared to resonances (http://en.wikipedia.org/wiki/Orbital_resonance) between other bodies.
Jupiter clears out a path of asteroids and comets by being so massive that it attracts them to itself to either fling it to an orbit in the asteroid belt or out to the Oort Cloud or takes a hit from it to prevent it from cluttering up the solar system.
If it wasn't for Jupiter and other gas giants, we'd have more comets and asteroids getting near the inner planets, so Saturn, Uranus, and Neptune are Soccer Goalies as well.
But they don't always stop everything, just a majority of it.
Early on when our solar system was being formed, there were a lot of collisions with Earth and our Moon, and some say some of the collisions helped life to form and evolve, but in later years fewer and fewer collisions happened until we have the modern day.
Remember, Slashdot does not have a -1 disagree moderation, and no, troll, flamebait, and overrated are not substitutes.
Ever hear of paragraphs? Jesus Christ guys, seriously now.
Well the story is better told as this:
Might Betelgeuse Go BOOM? http://www.rense.com/general86/boom.htm
Betelgeuse BOOM - Calamitas Apocalyptica http://www.rense.com/general86/beet.htm
Supernova Waves Rolled Over Mammoths http://www.astrobio.net/index.php?option=com_news&task=detail&id=1726
Both Betelgeuse And Antares - Update http://www.rense.com/general86/medb.htm
Last Sunday, an object, probably a comet that nobody saw coming, plowed into Jupiter
First, I'd like to apologize for being slightly off-topic.
I wonder why pretty much all astronomy sources are unwilling to state with certainty that Jupiter has a rocky core. It's only natural that more solid material has fallen into the atmosphere than has been captured in orbit. It's not like the comets and meteorites will 'orbit' for very long within friction of the atmosphere, so the only place for solid matter to go is the center.
We had 5 major mass extinctions in the past, but the most recent one isn't in the past at all but is happening right now. It began slowly with the rise of Man, but ramped up exponentially with the industrial revolution. Compared to previous extinction events, it's by far the worst of them by many orders of magnitude.
This astronomic loss of biodiversity isn't so much about high-profile rhinos and tigers and cute pandas, but about the almost unseen microbiota and microfauna throughout the biosphere, upon which all of our food and even our own bodies depend. It very rarely makes the news (not sexy enough), but we may not pull out of this one.
Apparently we don't need a big rock to hit us at all. We seem to be totally self-sufficient at achieving extinction.
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
(Pyongyang, NK) A defiant North Korea announced the launch of a projectile the size of several soccer fields (football fields in the U.S.) that struck Jupiter today. As it descended into Jupiter's cloud tops it was transmitting data and broadcasting the "Song of General Kim Il-sung" and "Song of General Kim Jong-Il", about Kim Jong-Il and his father.
North Korea's neighbors condemned the launch as "unfortunate". The U.S. State Department declined to comment, although in another display of his ability to mitigate, President Obama has invited Kim Jong-Il to meet him on Jupiter for a beer.
is dat somthin on which we shud bet our existence?
it can be made to work.
http://www.accountkiller.com/removal-requested
I would like to see your solution to Global Climate Change. Has there ever been a point where the Global Climate wasn't changing?
The purpose of language is communication, If the idea is clear the grammar ain't important
Maybe. But I find a bit scary that nobody noticed in space the large "object" before it crashed into Jupiter.
Hmm... no one saw it coming, and no one saw it leave. All we know is that it left a gaping hole in the side of Jupiter. It must have been space ninjas...
(There is supposed to be a Sarcmark® here, but my $1.99 check hasn't cleared, yet...)
Don't worry, we are well on the way of blowing the planet to smitherines ourselves. No amount of protection from Jupiter is going to stop our self-destruct sequence!
~Ami
Chicago Web Design
Well, for the time being and the foreseeable/coming future, i'm HAPPY to be covered by our massive JUPITER than massive URANUS.... From a software/hardware perspective, Jupiter is a better, smoother sheathe, but URANUS is ringed, chunky and reflective (if not coarse) for our (viewing) pleasure....
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
I forgot to say that some wild westerns do end with the heroes "riding off into the sunset"