gwiz
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|  | Re: Apollo 18: There's a reason why we never went « Reply #105 on Nov 2, 2011, 11:52am » | |
Nov 1, 2011, 10:00pm, ka9q wrote:| I think the use of L2 halo orbits for far side relays was first proposed in the late 1960s but I'm not sure. |
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While a science satellite rather than a relay, NASA's ARTEMIS P1 became the first object to attain an L2 halo orbit on 25 August 2010.
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Multiple exclamation marks are a sure sign of a diseased mind - Terry Pratchett ...the ascent module ... took off like a rocket - Moon Man |
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ka9q Saturn member is offline
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|  | Re: Apollo 18: There's a reason why we never went « Reply #106 on Nov 3, 2011, 4:02am » | |
Nov 2, 2011, 11:52am, gwiz wrote:| While a science satellite rather than a relay, NASA's ARTEMIS P1 became the first object to attain an L2 halo orbit on 25 August 2010. |
| I didn't know that so I looked it up. I found that these were among five Themis spacecraft originally launched into earth orbit in 2007. They completed their original missions in 2010 when two of the five were renamed Artemis and moved into elliptical lunar orbits through a complex sequence of maneuvers including temporary stays at the earth-moon L2 point.
These orbital ballets just keep getting better and better. The Pioneer and Voyager multi-planet tours of the 1970s and 80s were child's play compared to the complex maneuvers that have since become routine. I can see that modern computers make it easy to predict what any given set of maneuvers will do, but just how do they figure out those maneuvers in the first place? That's the part that still amazes me.
Thanks for the information!
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dwight
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|  | Re: Apollo 18: There's a reason why we never went « Reply #107 on Nov 15, 2011, 11:30pm » | |
I finally watched Apollo 18 and I must say I liked it alot. OK if I wanted to nit-pick the thing apart I could have, but for the suspense and post viewing images that stayed in my head while I slept, it really hit the mark. For a budget horror film, I thought it was cool.
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gtvc Venus member is offline
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Count Zero
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|  | Re: Apollo 18: There's a reason why we never went « Reply #109 on Nov 19, 2011, 11:11pm » | |
Arrrgh! They have the LM mirror-imaged on the mission patch. Considering how well they did the LK, I'm surprised they got that detail wrong.
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"What makes one step a giant leap is all the steps before." |
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echnaton
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