Is Jupiter Earth's Cosmic Protector? 222
Posted
by
Soulskill
from the sounds-like-we-should-deify-it-oh-wait dept.
from the sounds-like-we-should-deify-it-oh-wait dept.
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."
On a galactic note... (Score:5, Insightful)
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 that something we should bet our existence on? (Score:2, Insightful)
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!
A good reason for manned exploration... (Score:5, Insightful)
... is the fact that eventually we have to get off earth and learn how to survive in the hostile universe anyway.
Uhhhhhh.....NO (Score:0, Insightful)
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?
The end is nigh (Score:5, Insightful)
The Earth will eventually be wiped out, obviously. We can't get lucky forever.
We'd better spread outselves out.
hence the ongoing LEO beta test. (Score:2, Insightful)
Scatter! (Score:2, Insightful)
Re:A New Criteria? (Score:1, Insightful)
They decrease, since another big planet will more likely absorb other space bodies than emitting them ...
But others will be sent elsewhere. TFA and TFS are utter rubbish, in this respect. And the Sun exerts more gravitational force than any planet ... therefore (and contrary to what I said about planets), our odds of being hit are indeed increased by the Sun.
Re:Amazing (Score:5, Insightful)
Jupiter isn't exactly "near-earth," and doesn't count as "close to Earth" when you're talking about asteroids and comets hitting or almost hitting planets.
Re:Amazing (Score:3, Insightful)
Doesn't this only work in a 1-D universe? (Score:3, Insightful)
Re:Greater benefic (Score:3, Insightful)
Are you feeling jovial?
Re:The end is nigh (Score:1, Insightful)
Re:Luckily... (Score:4, Insightful)
There's actually no "Present Participle" for making/molding/pressing dies. The action itself is usually "pressing", "blanking", or "broaching". More information here [wikipedia.org].
On a side note, the Bengal tiger is quite intelligent and resourceful. I wouldn't be surprised if they did decide to go into the manufacturing business.
Re:Is that something we should bet our existence o (Score:3, Insightful)
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.
Re:Probabilities are hard to calculate... (Score:3, Insightful)
The circumference of Jupiter's orbit is about 760000 Earth radii so Jupiter is "shielding" about .000029 of its orbit, and that's assuming everything comes in exactly in the plane of Jupiter's orbit. It doesn't.
Re:Luckily... (Score:5, Insightful)
Re:Luckily... (Score:5, Insightful)
That's right. You can't.