Difference between revisions of "Talk:681: Gravity Wells"

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: It ''may'' be the height needed to go from one gravity well to another. You don't have to get all the way up to escape speed for that.
 
: It ''may'' be the height needed to go from one gravity well to another. You don't have to get all the way up to escape speed for that.
  
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:Adapted from the table in {{w|Escape_velocity#List_of_escape_velocities|Escape velocity}}, using ''h'' = ''V_e''^2 / 2''g'':
 
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{| class="wikitable" border="1"
 
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| Location || with respect to || Ve (km/s) || Well depth (km) ||
 
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| Location || with respect to || Ve (km/s) || Solar well (Mm) || Total depth (Mm) 
 
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|-
 
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| on the Sun, || the Sun's gravity: || 617.5 || 19,435,000 || || || || || || 19,435
 
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|-
 
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| on Mercury, || Mercury's gravity: ||  4.3 || 942 ||
 
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| at Mercury, || the Sun's gravity: || 67.7 || 233.6 || 235
 
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|-
 
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| on Venus,  || Venus' gravity:    || 10.3 || 5,407 ||
 
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| at Venus,  || the Sun's gravity:  || 49.5 || 124.9 || 130
 
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|-
 
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| on Earth, || the Earth's gravity: || 11.2 || 6,393 ||
 
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| at the Earth/Moon, || the Sun's gravity: || 42.1 || 90.3 || 97
 
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|-
 
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| on the Moon, || the Moon's gravity: || 2.4 || 294 ||
 
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| at the Moon, || the Earth's gravity: || 1.4 ||  || 91
 
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|-
 
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| on Mars, || Mars' gravity: || 5 || 1,274 ||
 
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| at Mars, || the Sun's gravity: || 34.1 || 59.3 || 61
 
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|-
 
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| on Jupiter, || Jupiter's gravity: || 59.5 || 180,400 ||
 
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| at Jupiter, || the Sun's gravity: || 18.5 || 17.4 || 198
 
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|-
 
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| on Ganymede, || Ganymede's gravity: || 2.7 || 372 || || || || || 
 
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|-
 
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| on Saturn, || Saturn's gravity: || 35.6 || 64,600 ||
 
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| at Saturn, || the Sun's gravity: || 13.6 || 9.43 || 74
 
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|-
 
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| on Uranus, || Uranus' gravity: || 21.2 || 22,907 ||
 
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| at Uranus, || the Sun's gravity: || 9.6 || 4.7 || 28
 
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| on Neptune, || Neptune's gravity: || 23.6 || 28,400 ||
 
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| at Neptune, || the Sun's gravity: || 7.7 || 3.02 || 31
 
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|-
 
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| on Pluto, || Pluto's gravity: || 1.2 || 73 || || || || ||
 
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|-
 
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|at Solar System <br/>galactic radius, || the Milky Way's gravity: || 525 || 14,000
 
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|}
 
 
: Randall wasn't kidding about the Sun being "very very far down"; its well is 100 times deeper than Jupiter's!
 
: Randall wasn't kidding about the Sun being "very very far down"; its well is 100 times deeper than Jupiter's!
 
:[[User:Wwoods|Wwoods]] ([[User talk:Wwoods|talk]]) 19:47, 12 April 2013 (UTC)
 
:[[User:Wwoods|Wwoods]] ([[User talk:Wwoods|talk]]) 19:47, 12 April 2013 (UTC)

Revision as of 15:35, 12 March 2014

Why is Earth's well's depth listed as 5478km but as 6379km in the inset? Compare with Mars which has 1286 in both places. 87.174.225.131 07:21, 12 April 2013 (UTC)

Best guess is either a goof, or that the lower number is just for Earth itself, while the greater number is for the Earth/Moon system as a whole. Proportionally speaking, we have the largest moon in the solar system, so maybe it wouldn't nicely fit in the Earth well as easily as Mars's and Jupiter's moons do.--Druid816 (talk) 08:28, 12 April 2013 (UTC)
It may be the height needed to go from one gravity well to another. You don't have to get all the way up to escape speed for that.
Randall wasn't kidding about the Sun being "very very far down"; its well is 100 times deeper than Jupiter's!
Wwoods (talk) 19:47, 12 April 2013 (UTC)
OTOH, from the table above i'm thinking that the 5.4 might be the Venus figure, and it was wrongly placed besides Earth...
Secondly, what i found interesting was that the Earth's 6.4 looks so much like its radius! I wonder if it's merely a coincidence, or there's a connection between the two... -- 141.101.99.233 21:25, 30 October 2013 (UTC)
The table is great, it must be included in the article; layout and time is just my problem right now. PRO TIP: Do not care about the x-axis.--Dgbrt (talk) 22:18, 30 October 2013 (UTC)
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