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#60
by
mr. mark
on 07 Feb, 2011 19:57
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#61
by
stockman
on 07 Feb, 2011 20:04
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Nice article courtesy of msnbc.com 
http://www.msnbc.msn.com/id/41461636/ns/technology_and_science-science/
"There's room aboard the Falcon 9 for another 240 pounds of additional cargo. Astrobotic Technology is selling the space for $700,000 per pound, plus a $250,000-per-payload fee for integration, communications and other support services. "
Something wrong with the math in this part of the article.. I put the cost for that 240lbs of Excess cargo capacity at 168 million dollars?? Nice profit if they can get it but I have to believe someone messed up the zero's in the article???
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#62
by
mr. mark
on 07 Feb, 2011 20:08
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#63
by
go4mars
on 07 Feb, 2011 20:50
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In 2012 their aim is to build 1 F9 every 6 weeks.
I'm hearing talk about a additional assembly facility but, for now just rumors in the space community.
Is there a rumored location? Such as extra space at the Tesla factory?
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#64
by
jabe
on 07 Feb, 2011 21:31
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I'm hearing talk about a additional assembly facility but, for now just rumors in the space community.
Now that would be interesting to see but that opens up lots of questions...
Where is the cash to do this.... Will they need a dual line of friction stir welding machines...pipe bending machines for the engines/octopus.. etc..
their overhead costs..man power and development...seems pretty high right now without that much cash flow in..
IPO maybe?
jb
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#65
by
wjbarnett
on 07 Feb, 2011 21:59
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Nice article courtesy of msnbc.com
http://www.msnbc.msn.com/id/41461636/ns/technology_and_science-science/
"There's room aboard the Falcon 9 for another 240 pounds of additional cargo. Astrobotic Technology is selling the space for $700,000 per pound, plus a $250,000-per-payload fee for integration, communications and other support services. "
Something wrong with the math in this part of the article.. I put the cost for that 240lbs of Excess cargo capacity at 168 million dollars?? Nice profit if they can get it but I have to believe someone messed up the zero's in the article???
I don't know, maybe not. I assume, since Astrobotic is selling this, it's payload to the Moon (either to LLO, on the lander or even on the rover, perhaps). That's worth a lot more than payload to LEO.
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#66
by
Jason1701
on 08 Feb, 2011 01:27
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Space.com published a story on this.
http://www.space.com/10787-private-moon-race-team-signs-rocket-deal-spacex.htmlSpaceX — which in December became the first private company to successfully return a spacecraft from Earth orbit — usually charges between $49.9 million and $56 million for a launch to low-Earth orbit. But it's lowering its prices for the prize.
"SpaceX is a Preferred Launch Partner, having offered substantial discount to all Google Lunar X Prize teams as a way of further fostering exploration and innovation," officials wrote on the X Prize website.
Very interesting. I wonder how many other teams will try to get an F9 ticket.
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#67
by
docmordrid
on 08 Feb, 2011 07:42
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Discovery News....Interesting quote from a Musk email -
"Falcon 9 is capable of launching missions to the moon, Mars or beyond. Payload to the moon is about three tons and to Mars about two tons, meaning Falcon 9 could have launched the Spirit and Opportunity Mars rovers on a single flight," wrote Musk.
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#68
by
Ben the Space Brit
on 08 Feb, 2011 07:53
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Discovery News....
Interesting quote from a Musk email -
"Falcon 9 is capable of launching missions to the moon, Mars or beyond. Payload to the moon is about three tons and to Mars about two tons, meaning Falcon 9 could have launched the Spirit and Opportunity Mars rovers on a single flight," wrote Musk.
The MERs were launched by Delta-II, weren't they? I think someone pointed out once that the current version of Falcon-9 is broadly in Delta-II's performance envelope.
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#69
by
rklaehn
on 08 Feb, 2011 08:01
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Nice article courtesy of msnbc.com
http://www.msnbc.msn.com/id/41461636/ns/technology_and_science-science/
"There's room aboard the Falcon 9 for another 240 pounds of additional cargo. Astrobotic Technology is selling the space for $700,000 per pound, plus a $250,000-per-payload fee for integration, communications and other support services. "
Something wrong with the math in this part of the article.. I put the cost for that 240lbs of Excess cargo capacity at 168 million dollars?? Nice profit if they can get it but I have to believe someone messed up the zero's in the article???
I don't know, maybe not. I assume, since Astrobotic is selling this, it's payload to the Moon (either to LLO, on the lander or even on the rover, perhaps). That's worth a lot more than payload to LEO.
It is definitely payload to the moon. They have some spare mass allocated on their lander. But even so it seems quite expensive.
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#70
by
ugordan
on 08 Feb, 2011 08:05
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Discovery News....
Interesting quote from a Musk email -
"Falcon 9 is capable of launching missions to the moon, Mars or beyond. Payload to the moon is about three tons and to Mars about two tons, meaning Falcon 9 could have launched the Spirit and Opportunity Mars rovers on a single flight," wrote Musk.
Same article I linked to
here, including the same Musk quote. Is it that hard to go back a page or two and check whether something is posted already?
F9 is supposed to noticeably exceed Delta II performance, but that doesn't matter here because the two MER point is irrelevant. Spacecraft operations team couldn't handle landing two mars rovers almost simultaneously, that's why they were launched 2 weeks apart.
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#71
by
rklaehn
on 08 Feb, 2011 08:35
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F9 is supposed to noticeably exceed Delta II performance, but that doesn't matter here because the two MER point is irrelevant. Spacecraft operations team couldn't handle landing two mars rovers almost simultaneously, that's why they were launched 2 weeks apart.
Couldn't you let the two probes fire their maneuvering thrusters directly after TMI or during midcourse correction to get them on trajectories that arrive at different days? Even a small delta-v would accumulate over the long hohmann transfer transit.
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#72
by
ugordan
on 08 Feb, 2011 08:44
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I don't have any insight into that, apart from some WAG, but I'd say spreading the landings two weeks apart would be well outside of the propulsive capabilities of the cruise stages. A day or two, maybe - but then again, that's still not enough for the operations team.
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#73
by
rklaehn
on 08 Feb, 2011 09:01
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I don't have any insight into that, apart from some WAG, but I'd say spreading the landings two weeks apart would be well outside of the propulsive capabilities of the cruise stages. A day or two, maybe - but then again, that's still not enough for the operations team.
For two weeks you would probably let the upper stage deploy the first probe, change the trajectory and then deploy the second probe. But do you really need two weeks? A day or two should be enough to get the first probe in a safe config where it can survive with minimal intervention.
Edit: Here is how you would do it: a straight hohmann transfer intersects the mars orbit in one point. But if you make the transfer orbit slightly more elliptical, then it intersects the mars orbit in two points. Even a very slight excess velocity compared to a hohmann transfer will lead to a large distance (=time) between the two intersection points.
Now all you have to do is to change the orbital parameters of one probe so that arrives at the first crossing point when mars is there, and of the other probe so that it misses at the first crossing point but hits on the second crossing point.
I am quite confident you could do something like this even with very modest delta-v. But you will definitely be able to do it by using a restartable upper stage such as the one from falcon 9.
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#74
by
notsorandom
on 08 Feb, 2011 09:03
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Discovery News....
Interesting quote from a Musk email -
"Falcon 9 is capable of launching missions to the moon, Mars or beyond. Payload to the moon is about three tons and to Mars about two tons, meaning Falcon 9 could have launched the Spirit and Opportunity Mars rovers on a single flight," wrote Musk.
The MERs were launched by Delta-II, weren't they? I think someone pointed out once that the current version of Falcon-9 is broadly in Delta-II's performance envelope.
The Delta II Heavy is about 2/3 the mass of the Falcon 9 and uses a less efficient upper stage combination. Its more in the category of the EELVs. If they ever get a Raptor LH2 stage the Falcon 9 should turn out to be even more impressive. It is interesting that this team is using the Falcon 9 and not the Falcon 1.
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#75
by
ugordan
on 08 Feb, 2011 09:12
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It is interesting that this team is using the Falcon 9 and not the Falcon 1.
Think of the payload (or lack of thereof) a Falcon 1e could sling to the Moon and that's requiring a 3rd stage by default.
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#76
by
ugordan
on 08 Feb, 2011 09:16
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But do you really need two weeks? A day or two should be enough to get the first probe in a safe config where it can survive with minimal intervention.
It's not just the EDL maneuver, it's the tracking requirements, any last-minute TCMs etc before landing. Plus if anything unexpected happened on the first lander, you wouldn't have much time to apply a lesson learned for the 2nd lander. Case in point: the atmospheric density during Spirit landing was lower than expected and had the parachutes deployed just a couple of seconds later, the thing would have crashed into the ground. For Opportunity landing the timings were adjusted.
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#77
by
rklaehn
on 08 Feb, 2011 09:41
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I don't have any insight into that, apart from some WAG, but I'd say spreading the landings two weeks apart would be well outside of the propulsive capabilities of the cruise stages. A day or two, maybe - but then again, that's still not enough for the operations team.
For two weeks you would probably let the upper stage deploy the first probe, change the trajectory and then deploy the second probe. But do you really need two weeks? A day or two should be enough to get the first probe in a safe config where it can survive with minimal intervention.
Edit: Here is how you would do it: a straight hohmann transfer intersects the mars orbit in one point. But if you make the transfer orbit slightly more elliptical, then it intersects the mars orbit in two points. Even a very slight excess velocity compared to a hohmann transfer will lead to a large distance (=time) between the two intersection points.
Now all you have to do is to change the orbital parameters of one probe so that arrives at the first crossing point when mars is there, and of the other probe so that it misses at the first crossing point but hits on the second crossing point.
I am quite confident you could do something like this even with very modest delta-v. But you will definitely be able to do it by using a restartable upper stage such as the one from falcon 9.
Here is an illustration of the concept. Blue is earth orbit, dark red is mars orbit, black is a hohmann transfer.
Green is the first MER. violet is the second MER. The orbits are pretty similar, but nevertheless intercept mars at a long distance in its orbit. In reality, the difference from a hohmann transfer to the transfer orbit would be much smaller.
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#78
by
ugordan
on 08 Feb, 2011 09:46
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Do you have a rough idea of the delta-V for the two trajectories? Looks 100-ish meters per second to my untrained eyeballs.
Also consider that the arriving trajectory geometry is not "free-floating", there are constraints on landing site time of day, entry angle, etc.
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#79
by
rklaehn
on 08 Feb, 2011 10:02
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Do you have a rough idea of the delta-V for the two trajectories? Looks 100-ish meters per second to my untrained eyeballs.
That would be my guess as well. But that is well within the capability of a falcon 9 upper stage.
Note that this is not to scale. For a delay of just 14 days the intersection points would be much closer together (about (14/687)*360 = 7°), and the two orbits would be so close together that you would not be able to distinguish them.
Also consider that the arriving trajectory geometry is not "free-floating", there are constraints on landing site time of day, entry angle, etc.
Yes, there would be some constraints on the landing geometry. To really analyse this thoroughly you would need some expensive tools or a lot of time. But it does not seem completely implausible at first glance, and people are remarkably creative when designing trajectories.
