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A few months ago someone posted on HN about "ballistic capture" to enter a Martian orbit with far less fuel, and I've spent the last few months wondering if you

A few months ago someone posted on HN about "ballistic capture" to enter a Martian orbit with far less fuel, and I've spent the last few months wondering if you could do that to mosey into a Plutonian orbit: http://www.scientificamerican.com/article/a-new-way-to-reach-mars-safely-anytime-and-on-the-cheap/ http://www.scientificamerican.com/article/a-new-way-to-reach...

skykooler 11y ago
Part of the reason New Horizons is going so fast is to reach Pluto in "only" ten years. A Hohmann transfer (which you would need to make a ballistic capture) would take about 124 years just to reach Pluto.
- eastbayjake 11y ago
  The article led me to believe you would avoid a Hohmann transfer with ballistic capture by flying it into a similar orbit and letting the planet slowly creep up on the probe and pull it into orbit. Am I misreading that?
  - Dylan16807 11y ago
    You're cutting the final burn but you're still pulling roughly the same maneuver, by taking an orbit that peaks at about the same altitude as pluto, and that is a slow orbit.
kartikkumar 11y ago
My boss co-authored that paper [1] :) Ballistic capture is interesting: makes use of fuzzy/chaotic dynamics in the 3-Body Problem. I worked on analysis of the Weak Stability Boundary, which is the mathematical set of all points in phase-space that lie at this fuzzy boundary, for my Masters thesis [2]. It has been used in a few missions, including SMART-1, Stardust, and Hiten. ESA's Bepi-Colombo mission will also be using it to ensure that there isn't a single point-of-failure to enter orbit around Mercury. The big problem with ballistic capture is that it doesn't guarantee a more optimal solution. Transfers can take a lot longer, and in theory even require more fuel. So it's very much a case of having to perform mission analysis on a case-by-case basis. Nevertheless, it's an interesting prospect to send unmanned missions to Mars carrying habitat elements, before a manned mission, since they can be sent well in advance. I analyzed the prospect of potentially using a cycler [3] for this in my thesis. [1] http://arxiv.org/abs/1410.8856 http://arxiv.org/abs/1410.8856 [2] http://repository.tudelft.nl/view/ir/uuid%3Ae8c99c80-a25d-4c7b-b8c2-f0f27c69fc32/ http://repository.tudelft.nl/view/ir/uuid%3Ae8c99c80-a25d-4c... [3] http://courses.ae.utexas.edu/ase333t/past_projects/04spring/Cycler%20Website/cyclers.html http://courses.ae.utexas.edu/ase333t/past_projects/04spring/...
- HopDavid 11y ago
  When mass parameter is big, use of WSBs is interesting. But mass parameters for sun-earth or sun-Mars are tiny. I've expressed my skepticism for ITN between earth and Mars: http://hopsblog-hop.blogspot.com/2015/04/potholes-on-interplanetary-superhighway.html http://hopsblog-hop.blogspot.com/2015/04/potholes-on-interpl...

skykooler 11y ago

Part of the reason New Horizons is going so fast is to reach Pluto in "only" ten years. A Hohmann transfer (which you would need to make a ballistic capture) would take about 124 years just to reach Pluto.

eastbayjake 11y ago
The article led me to believe you would avoid a Hohmann transfer with ballistic capture by flying it into a similar orbit and letting the planet slowly creep up on the probe and pull it into orbit. Am I misreading that?
- Dylan16807 11y ago
  You're cutting the final burn but you're still pulling roughly the same maneuver, by taking an orbit that peaks at about the same altitude as pluto, and that is a slow orbit.

kartikkumar 11y ago

My boss co-authored that paper [1] :) Ballistic capture is interesting: makes use of fuzzy/chaotic dynamics in the 3-Body Problem. I worked on analysis of the Weak Stability Boundary, which is the mathematical set of all points in phase-space that lie at this fuzzy boundary, for my Masters thesis [2]. It has been used in a few missions, including SMART-1, Stardust, and Hiten. ESA's Bepi-Colombo mission will also be using it to ensure that there isn't a single point-of-failure to enter orbit around Mercury. The big problem with ballistic capture is that it doesn't guarantee a more optimal solution. Transfers can take a lot longer, and in theory even require more fuel. So it's very much a case of having to perform mission analysis on a case-by-case basis. Nevertheless, it's an interesting prospect to send unmanned missions to Mars carrying habitat elements, before a manned mission, since they can be sent well in advance. I analyzed the prospect of potentially using a cycler [3] for this in my thesis. [1] http://arxiv.org/abs/1410.8856 http://arxiv.org/abs/1410.8856 [2] http://repository.tudelft.nl/view/ir/uuid%3Ae8c99c80-a25d-4c7b-b8c2-f0f27c69fc32/ http://repository.tudelft.nl/view/ir/uuid%3Ae8c99c80-a25d-4c... [3] http://courses.ae.utexas.edu/ase333t/past_projects/04spring/Cycler%20Website/cyclers.html http://courses.ae.utexas.edu/ase333t/past_projects/04spring/...

HopDavid 11y ago
When mass parameter is big, use of WSBs is interesting. But mass parameters for sun-earth or sun-Mars are tiny. I've expressed my skepticism for ITN between earth and Mars: http://hopsblog-hop.blogspot.com/2015/04/potholes-on-interplanetary-superhighway.html http://hopsblog-hop.blogspot.com/2015/04/potholes-on-interpl...