Saturn Overtakes Jupiter As Host To Most Moons In Solar System (theguardian.com) 34
Astronomers have spotted 20 more moons orbiting Saturn, bringing the total number of Saturnian moons to 82, surpassing the 79 that are known to orbit Jupiter. The Guardian reports: The scientists discovered the moons when they set algorithms to work on decade-old images captured from the powerful Subaru telescope on Mauna Kea in Hawaii. By comparing images taken over hours and days, the algorithms distinguished between stationary stars and galaxies and moons that hurtled around the planet. Depending on the angle of approach, comets and asteroids straying too close to Saturn in the early solar system would have become locked into radically different orbits around the planet. Only three of the new moons have so-called prograde orbits, meaning they circle Saturn in the same direction that it rotates. The other 17 are in retrograde orbits, meaning they orbit the planet backwards. One is the most distant moon ever spotted from the planet.
The outer moons of Saturn fall into three broad families according to how they orbit the gas giant. Two of the new prograde moons appear to belong to a group that swings around Saturn at an angle of about 46 degrees. The moons, named after Inuit mythology, may once have belonged to one far larger moon that broke apart in the distant past. The new retrograde moons appear to belong to another group named after Norse mythology and are also thought to be fragments of a much bigger parent moon that was smashed to pieces in the solar system's violent past.
The outer moons of Saturn fall into three broad families according to how they orbit the gas giant. Two of the new prograde moons appear to belong to a group that swings around Saturn at an angle of about 46 degrees. The moons, named after Inuit mythology, may once have belonged to one far larger moon that broke apart in the distant past. The new retrograde moons appear to belong to another group named after Norse mythology and are also thought to be fragments of a much bigger parent moon that was smashed to pieces in the solar system's violent past.
Overly decorative language (Score:1)
Is it just me? Or could
"...smashed to pieces in the solar system's violent past."
Just have been written as
"...smashed to pieces."
?
Early bombardment (Score:5, Informative)
The language has been used to try to convey the information that over the eons since the birth of the solar system, the "smashing to pieces" has progressively decreased as there are have been less and less left over asteroids to do the smashing part.
The past has been much more violent than the present era when most of the asteroid have already been smashed and the left overs are much stable.
e.g.: Nowadays, the Earth is seeing a lot less smashing than a couple of billion years ago. (Though in the Earth's specific case, the Moon has also played an important role in that by playing the role of a giant asteroid collector / shield. Still the planets eventually clearing their orbit of debris is also the reason why there's less left over now)
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Is it just me? Or could "...smashed to pieces in the solar system's violent past." Just have been written as "...smashed to pieces." ?
Could've just been written "smashed"
Wake me (Score:3)
when they have counted all the bits in Saturn's rings.
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Oblig (Score:1)
That's no moon!
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The IAU is going to have to come up with some definition of what a moon is.
The most useful leading definition candidate is currently, "Not a Death Star" -- so don't hold your breath ...
Whats the minimum size for a moon? (Score:3)
It seems they're increasingly including random lumps of rock that arn't even close to being round. So how large do they have to be? 1km, 100m, 1m? Or is there no minimum size in which case they might as well include ever bit of rock floating in the rings.
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I don't think it's going to be a hard fast rule like that.
It will probably need to take into account the number of nearby objects, not just their size, in considering something a moon.
A planet with a single object at 10 km is easier to classify than a plant with 100's of 10 km objects.
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I'd vote for either: large enough to clear it's own orbit if not for the object it's orbiting, though that probably would remove a lot of existing ones, or: say pick a relative ratio: anything in a stable orbit greater than 1% by mass of the body they orbit or some other percentage. That way rocks in the rings will still just be rocks, but smaller rocks that orbit smaller objects could get moon status (we don't want to be sizist ;)).
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Insisting on categorizing everything precisely is so nineteenth century science. By now we should recognize that categories are useful, but are only a linguistic tool, not the end objective of science. The more we learn, especially about astronomy, the more we realize that any arbitrary boundary will have objects sitting right on top of it, breaking any categorization system we try to throw at it. So let's just relax and recognize that language isn't precise, enjoy a world with panda bears and starfish,
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Without categories and definitions there would be no science since either no one would know what you were talking about or you'd have to spend 30 mins explaining everything before getting to the point each time so your argument is slightly ridiculous.
Werewolves on Saturn (Score:4, Funny)
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I saw a werewolf with a Martian menu in his hand
Walking through the streets of Saturn in the rain
He was looking for a place called Hyperion
Gonna get a big dish of cosmic flan
Aaoooooooo
Werewolves of Saturn..
Aaoooooooo
You hear him howling around your planet's rings...
With apologies to Warren Zevon
Was this written by a bot? (Score:2)
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Re:Was this written by a bot? (Score:4, Funny)
Can't compete with Laguna Niguel station (Score:2)
Saturn may have this year's gala event... (Score:2)
... but the after party is still ragin' at Neptune.
Qualified (Score:2)
The largest moons, however, are from the planet Kardashian, though they were disqualified because they were all artificial.
Depends on the definition.... (Score:2)
Does it need to be in a circular orbit, does it need to orbit at all or just be gravitationally bound ?
The rings might count ....
the Trojans might count ...
Following NASA's lead. (Score:2)
Because Saturn [wikipedia.org] is clearly much better than Jupiter. [wikipedia.org]
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Dammit. Wrong link for Jupiter. https://en.wikipedia.org/wiki/... [wikipedia.org]
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My father's view of moons (Score:2)
I remember my father's response when I told him about 20 years ago that Jupiter had multiple moons: "Why would God put so many moons there when there's no-one there to see their moonlight?"
Earth looking like Chumps (Score:2)