(Paper) Evidence of a Jovian Mass Solar Companion in the Oort Cloud? |
(Paper) Evidence of a Jovian Mass Solar Companion in the Oort Cloud? |
Apr 28 2010, 09:26 PM
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#16
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
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Apr 29 2010, 05:34 AM
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#17
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Great, something ELSE to add on to our Solar System Scale Model... !
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Apr 29 2010, 09:16 AM
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#18
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Junior Member Group: Members Posts: 94 Joined: 22-May 08 From: Loughborough Member No.: 4121 |
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Apr 29 2010, 02:22 PM
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#19
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Brilliant! Thanks PFK, you just scribbled one item off my To Do list for me!
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Apr 29 2010, 11:57 PM
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#20
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Junior Member Group: Members Posts: 66 Joined: 8-November 05 From: Australia Member No.: 547 |
Not wanting to inject controversy into this thread but if Tyche does indeed exist, would the current IAU "rules" result in this object being considered a planet or a "dwarf"? Its a good assumption to believe the object will have reached hydrostatic equilibrium and be a spheroid, but has it cleared its neighbourhood of debris and minor objects?
Wouldn't it be ironic (hilarious) if Sols largest companion was classified by IAU as a dwarf planet due to a technicality? |
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Apr 30 2010, 12:15 AM
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#21
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Member Group: Members Posts: 754 Joined: 9-February 07 Member No.: 1700 |
Wouldn't Jupiter have to be upgraded to "Failed Star"?
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Apr 30 2010, 12:42 AM
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#22
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Senior Member Group: Members Posts: 1431 Joined: 26-July 08 Member No.: 4270 |
I interpret the rule to mean that the object has to gravitationally dominate its region of space. Thus Earth, Jupiter, and Neptune are still planets, as would be "Tyche."
-------------------- -- Hungry4info (Sirius_Alpha)
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Apr 30 2010, 02:05 AM
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#23
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Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
What is the total mass of the Oort Cloud? I'm pretty sure it is vastly less than 1 Jupiter mass (as supposedly Jupiter outweighs everything else in the System combined, except the Sun) in which case this object would (as I understand it) be considered dominant in its region, as it outweighed all the debris in its orbit (as, say, Ceres doesn't.)
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Apr 30 2010, 02:12 AM
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#24
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
I wouldn't be surprised it's vastly less than an Earth mass...probably less than even that of the Moon. Lotta snowballs out there, not much rock.
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Apr 30 2010, 02:31 AM
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#25
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
I see it estimated anywhere from 40 Earth masses to as little as 1.
Lots of Oort, not so much cloud. ;-) --Greg |
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Oct 2 2010, 02:38 AM
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#26
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Member Group: Members Posts: 754 Joined: 9-February 07 Member No.: 1700 |
It gets a little confusing to hear about the Voyagers approaching one type of solar system boundary, while the Oorties are so much further out there!
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Oct 2 2010, 07:37 AM
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#27
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
What's the Hillsphere of the Sun?
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Oct 2 2010, 08:00 AM
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#28
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
What's the Hillsphere of the Sun? From this quick Google grab: "If it is agreed to assume a Hill sphere for the boundaries of the solar system [230,000au], it is found that these boundaries extend to the nearest stars. However, stable motion of the planets (with direct motion) probably is possible only within the solar gravitational sphere. [4500au]" |
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Oct 2 2010, 08:42 AM
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#29
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
I was going to ask why the radius of the Sun's Hill sphere would have to be "assumed", but then I found this calculator to approximate it. Since it involves the masses of two bodies, I guess that a sufficiently massive planet could be in solar orbit at a considerable distance (much greater than I'd thought possible).
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Oct 2 2010, 08:57 AM
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#30
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
Looking back to the previous page (621) to the page I link (622), It looks like the two bodies used are the sun and the whole galaxy. The major assumptions are the mass of the galaxy and assuming that mass to be concentrated at the center of the galaxy. I wonder if more recent calculations deviate much from this one.
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