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Gravity Wells

Posted: Mon Dec 28, 2009 4:48 pm
by Orca
Gravity wells, XKCD style!

Re: Gravity Wells

Posted: Mon Dec 28, 2009 5:03 pm
by geckzilla
Haha, the silly Sagan reference in the upper right corner... I don't think my mom's gravity well was ever deep enough to trap the football team, though. :lol:

Re: Gravity Wells

Posted: Mon Dec 28, 2009 6:05 pm
by neufer
Orca wrote:Gravity wells, XKCD style!
It takes half the amount of energy to launch something into orbit as to launch something on an escape trajectory;
ergo, the Shuttle & all those satellites should really be placed at half the distance to the (escape trajectory) goal from where they are currently placed.

(My local football team is the Washington Redskins who actual are in a state of free fall.)

Re: Gravity Wells

Posted: Tue Dec 29, 2009 7:06 pm
by Orca
neufer wrote:
Orca wrote:Gravity wells, XKCD style!
It takes half the amount of energy to launch something into orbit as to launch something on an escape trajectory;
ergo, the Shuttle & all those satellites should really be placed at half the distance to the (escape trajectory) goal from where they are currently placed.
Sure, there is bound to be a few glitches with a cartoon-diagram. It's still pretty neat-o. Now if you'll excuse me, I am going to ride my bike off Deimos...

Deimos beautiful moon in the world

Posted: Tue Dec 29, 2009 7:34 pm
by neufer
Orca wrote:
neufer wrote:It takes half the amount of energy to launch something into orbit as to launch something on an escape trajectory;
ergo, the Shuttle & all those satellites should really be placed at half the distance to the (escape trajectory) goal from where they are currently placed.
Sure, there is bound to be a few glitches with a cartoon-diagram. It's still pretty neat-o.
Now if you'll excuse me, I am going to ride my bike off Deimos...
You may be able to escape from the gravity well of Deimos on your bike
(provided you can solve a formidable 0.0004g traction problem) but
you won't escaped the same 'half orbital' Martian gravity well that Deimos is trapped in.

So expect a "re-accretion" return to Deimos soon:
Image
http://planetary.org/blog/article/00002275/ wrote:
Deimos in color from Viking Orbiter 2
Image

<<The Viking orbiters are the only spacecraft to have obtained views of anything but Deimos' Mars-facing hemisphere. This view is composed of four images taken by Viking Orbiter 2 on August 25, 1977 through red, green, violet, and clear filters. It is a view up into the enormous crater that dominates the southern hemisphere of Deimos. It is hypothesized that the ejecta from this crater re-accreted onto Deimos, producing its oddly smooth surface. This basin, like all but two of the craters on Deimos' surface, is not named.>> Credit: NASA / JPL / color composite by Emily Lakdawalla

Re: Gravity Wells

Posted: Tue Dec 29, 2009 7:42 pm
by geckzilla
Art Neuendorffer - Astronomical Information Aggregator and Destroyer of Juvenile Ambitions.

Re: Gravity Wells

Posted: Tue Dec 29, 2009 7:55 pm
by Orca
geckzilla wrote:Art Neuendorffer - Astronomical Information Aggregator and Destroyer of Juvenile Ambitions.
So you're saying that even if I had a DeLorean I couldn't escape? Art, you're not thinking four-dimensionally!

Re: Gravity Wells

Posted: Tue Dec 29, 2009 8:10 pm
by neufer
Orca wrote:
geckzilla wrote:Art Neuendorffer - Astronomical Information Aggregator and Destroyer of Juvenile Ambitions.
So you're saying that even if I had a DeLorean I couldn't escape? Art, you're not thinking four-dimensionally!
Actually, Einstein taught us that gravitational wells are four-dimensional.

Two-dimensional gravitational well cartoons just don't do them justice.

Re: Gravity Wells

Posted: Wed Dec 30, 2009 4:53 pm
by Orca
neufer wrote:
Orca wrote:
geckzilla wrote:Art Neuendorffer - Astronomical Information Aggregator and Destroyer of Juvenile Ambitions.
So you're saying that even if I had a DeLorean I couldn't escape? Art, you're not thinking four-dimensionally!
Actually, Einstein taught us that gravitational wells are four-dimensional.

Two-dimensional gravitational well cartoons just don't do them justice.
This is true. I am just not as good as you at providing links when I make cultural references. For some strange reason I have been making a lot of Back To The Future jokes lately.

The DeLorean has to go 88 mph to time travel. This is a problem in the past since there are no gas stations or paved roads yet. The only thing in the 1800's that could get even close was a train. So, Marty and the wacky professor pushed the time machine with a train across an incomplete bridge. Marty asks, "but we'll crash, the bridge is only half done!" The professor responds with, "Marty, you're not thinking four-dimensionally!" because in the future, where the DeLorean is going to appear, the bridge is already done...they just have to get to 88 mph before they reach the end of the bridge.

The second and third Back To The Future movies were lame, but for some reason I always remembered that line.

Re: Gravity Wells

Posted: Wed Dec 30, 2009 5:40 pm
by geckzilla
Hah, I have been watching Battlestar Galactica lately and if it weren't for this forum I wouldn't find half as many things wrong with the show. I mean, on my own, it only falls apart when they start talking about the computer systems but thanks to you guys I get mildly annoyed every time someone says "A blind jump? You could end up inside the sun!" (which, by the way, is being said by people who aren't even sure Earth exists) and don't even get started on the FTL drives, or why there always happens to be a planet or a moon nearby... They teleported next to this space weapons warehouse/cache thing and somehow ended up in "geosynchronous orbit" around it. And the space dock thing is also just sitting in the middle of some nebula like the nebula is just a relatively small, thunderstorm type cloud with lightning in it and everything. :lol:

Oh well, I forgive it. All except for the scene where a cylon cuts a fiber optic cable with a pocket knife, slits her wrist, and interfaces with it by sticking it in a vein. Yes, I'm going to send signals through a fiber optic cable using my blood! Brilliant!

Re: Gravity Wells

Posted: Wed Dec 30, 2009 5:45 pm
by BMAONE23
Gekzilla,
Don't forget...They're Frackin Skin Jobs...They can do anything

Re: Gravity Wells

Posted: Wed Dec 30, 2009 5:48 pm
by geckzilla
Yes, sure, they replicated the human body exactly, except with the added benefit that their blood can interface with rough cut fiber optic cables. :lol:

Re: Gravity Wells

Posted: Wed Dec 30, 2009 5:51 pm
by BMAONE23
geckzilla wrote:Yes, sure, they replicated the human body exactly, except with the added benefit that their blood can interface with rough cut fiber optic cables. :lol:
We are almost there ourselves
http://www.physorg.com/news122819670.html

Re: Gravity Wells

Posted: Wed Dec 30, 2009 6:20 pm
by neufer
Orca wrote: The DeLorean has to go 88 mph to time travel.
http://en.wikipedia.org/wiki/88_%28number%29 wrote:
<<Eighty-eight is:
  • * The atomic number of radium (; note, however, the DeLorean used plutonium 94)]
    * The number of days it takes Mercury to orbit the sun
    * The number of constellations in the sky
    * The number of keys on a piano
    >>

Re: Gravity Wells

Posted: Wed Dec 30, 2009 6:35 pm
by geckzilla
BMAONE23 wrote:
geckzilla wrote:Yes, sure, they replicated the human body exactly, except with the added benefit that their blood can interface with rough cut fiber optic cables. :lol:
We are almost there ourselves
http://www.physorg.com/news122819670.html
That's an entirely different concept. LCD displays and fiber optic cables have almost nothing in common in the way that they transmit data.