bhankiii - 1/5/2007 12:04 PMAll this talk about traveling to Gliese 581 has got me to thinking. The New Horizon probe, and other spacecraft, use gravitational assist flybys of Jupiter and other planets to gain speed. What are the theoretical limits to this sort of thing? How much speed could you pick up if you spent several years doing this before heading out of the solar system?
Tom Ligon - 1/5/2007 1:29 PMYes, you must work the directions of the planetary motions in. And the effect is primarily in the ecliptic.To reach Jupiter in the first place, the usual procedure may involve a swing past Venus, back past Earth and/or Luna, another swing past Venus, and off to Jupiter for the big boost. The mind fairly reels at the math overload, but every pass is a slingshot designed to boost the kinetic energy of the spacecraft.
Tom Ligon - 1/5/2007 2:14 PM Luna slingshots.
Jim - 1/5/2007 3:47 PMQuoteTom Ligon - 1/5/2007 2:14 PM Luna slingshots.The moon was never used
Tom Ligon - 1/5/2007 1:14 PMJim,Ah, those were the good old days! Use a big rocket, skip the Venus/Luna slingshots.
kevin-rf - 1/5/2007 5:09 PMActually the just launched Stereo mission used a lunar gravity assist.For some reason I thought ICE (formerly ISEE-3) used a lunar assist to get to Comet Giacobini-Zimmer back in the eighties...
Ankle-bone12 - 3/5/2007 5:09 PMWhen a probe uses a gravity assist and takes a planets ( say Jupiter) gravity, does Jupiter eventually regain that lost "orbit" from when it slows down? if not, then we could theoretically send millions of Gravity Assist probes past jupiter and its rotation would slow drastically. Sombody please correct me as i think i am wrong here.
Jim - 3/5/2007 4:45 PMQuoteAnkle-bone12 - 3/5/2007 5:09 PMWhen a probe uses a gravity assist and takes a planets ( say Jupiter) gravity, does Jupiter eventually regain that lost "orbit" from when it slows down? if not, then we could theoretically send millions of Gravity Assist probes past jupiter and its rotation would slow drastically. Sombody please correct me as i think i am wrong here.Correctit is a momentum exchange. The amount gained by the spacecraft is lost by the planet. But it is not the planet rotation that gravity assist affects, it is the orbit around the sun
Ankle-bone12 - 4/5/2007 5:30 PMQuoteJim - 3/5/2007 4:45 PMQuoteAnkle-bone12 - 3/5/2007 5:09 PMWhen a probe uses a gravity assist and takes a planets ( say Jupiter) gravity, does Jupiter eventually regain that lost "orbit" from when it slows down? if not, then we could theoretically send millions of Gravity Assist probes past jupiter and its rotation would slow drastically. Sombody please correct me as i think i am wrong here.Correctit is a momentum exchange. The amount gained by the spacecraft is lost by the planet. But it is not the planet rotation that gravity assist affects, it is the orbit around the sunThanks so much for clarifying that. I can now sleep at night knowing that The planets will never stop spinning, ( though they may someday become a fixed star in are sky some day,.. if humans still around that is.