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 2012-10-20, 04:36 #1 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 2·4,597 Posts Off to Alpha Centauri Bb ! ? If you don't know what the title is referring to please read: http://en.wikipedia.org/wiki/Alpha_Centauri_Bb So, I lay before you a challenge... Given that this is the closest exo-planet. And humans have a tendency to do things, "Because it is there." Please describe for us your plans for a mission (manned or unmanned) to visit said system. Constraints are as follows:You have 10,000,000,000 to spend on the project. (This includes cost of monitoring the mission until it crosses the orbit of Neptune, but not the rest of the journey [assumes that this becomes a line item in a budget]). You have 15 years until it must leave earth orbit (with 2 years to extend it if need for planetary slingshot alignment). Assumes access to all previously developed (and known) technology (e.g. the Saturn V could be resurrected). Assume only reasonable evolutionary technological advances (i.e. no warp drive, etc.) Please describe your launch system, the space ship that you are sending, the instruments, the flight plan, and anything else of interest to your plan (how long would it take, would you include a TAU type mission as well?, wtc.)  2012-10-20, 05:05 #2 ixfd64 Bemusing Prompter "Danny" Dec 2002 California 2×52×47 Posts I remember my 7th grade science teacher giving us a very similar challenge. In any case, I think I'd be more concerned about the 1,200 °C surface temperature than the cost. 2012-10-20, 07:35 #3 xilman Bamboozled! "𒉺𒌌𒇷𒆷𒀭" May 2003 Down not across 290716 Posts Quote:  Originally Posted by Uncwilly If you don't know what the title is referring to please read: http://en.wikipedia.org/wiki/Alpha_Centauri_Bb So, I lay before you a challenge... Given that this is the closest exo-planet. And humans have a tendency to do things, "Because it is there." Please describe for us your plans for a mission (manned or unmanned) to visit said system. Constraints are as follows:You have10,000,000,000 to spend on the project. (This includes cost of monitoring the mission until it crosses the orbit of Neptune, but not the rest of the journey [assumes that this becomes a line item in a budget]). You have 15 years until it must leave earth orbit (with 2 years to extend it if need for planetary slingshot alignment). Assumes access to all previously developed (and known) technology (e.g. the Saturn V could be resurrected). Assume only reasonable evolutionary technological advances (i.e. no warp drive, etc.) Please describe your launch system, the space ship that you are sending, the instruments, the flight plan, and anything else of interest to your plan (how long would it take, would you include a TAU type mission as well?, wtc.)
The 10 gigabuck limit instantly discounts a manned mission, unless you don't mind one or more corpses arriving there in a few tens of kiloyears.

First unspecified constraint: what is the required mission time? If you want arrival within a decade the technology is very different from what's required for a century mission or a millennium mission. I realise this is part of your challenge but it would be interesting to discover what might be thought reasonable.

Personally, I'd take the view of the Daedalus project team and require data to be returned within a century and preferably a few decades. That itself suggests that the craft needs to be capable of travelling at least 0.1c. The Daedalus mission profile certainly can't be implemented for $10G. Provide$10T and you may be in with a chance.

 2012-10-20, 07:45 #4 xilman Bamboozled!     "𒉺𒌌𒇷𒆷𒀭" May 2003 Down not across 33·389 Posts Useful background reading: http://www.icarusinterstellar.org/icarusppd.pdf
2012-10-20, 21:19   #5
Uncwilly
6809 > 6502

"""""""""""""""""""
Aug 2003
101×103 Posts

2×4,597 Posts

Quote:
 Originally Posted by xilman The 10 gigabuck limit
The funding level was an intentional choice to make it very doable with a reasonable level of will by some entity.

Quote:
 First unspecified constraint: what is the required mission time? .... I realise this is part of your challenge but it would be interesting to discover what might be thought reasonable.
Indeed that was part of the consideration. A fast transit time with low residency time in system vs. a slower transit time with longer residency in system. What would the various members choose? What are the boost technologies that they would wish to use? Etc.
Quote:
 The Daedalus mission profile certainly can't be implemented for $10G. Provide$10T and you may be in with a chance.
I chose a smaller budget deliberately. Also, I gave a launch window for TACI[SUB]Trans-Alpha Centauri Injection[/SUB].
Daedalus is not feasible in that time frame. 15 years of will for the time to TACI is a sustainable level of support. 30 years until TACI is not.

2012-10-20, 22:17   #6
science_man_88

"Forget I exist"
Jul 2009
Dumbassville

26×131 Posts

Quote:
 Originally Posted by xilman The 10 gigabuck limit instantly discounts a manned mission, unless you don't mind one or more corpses arriving there in a few tens of kiloyears. First unspecified constraint: what is the required mission time? If you want arrival within a decade the technology is very different from what's required for a century mission or a millennium mission. I realise this is part of your challenge but it would be interesting to discover what might be thought reasonable. Personally, I'd take the view of the Daedalus project team and require data to be returned within a century and preferably a few decades. That itself suggests that the craft needs to be capable of travelling at least 0.1c. The Daedalus mission profile certainly can't be implemented for $10G. Provide$10T and you may be in with a chance.
without accounting for relativity I get that to get there in a century you would need a speed equivalent to going to Voyager 1 in about 1400 seconds. also to the Saturn V idea suggested good luck: apollosaturn.com suggest a first estimate of \$7 billion USD for the original missions I think.

2012-10-21, 07:49   #7
xilman
Bamboozled!

"𒉺𒌌𒇷𒆷𒀭"
May 2003
Down not across

33×389 Posts

Quote:
 Originally Posted by Uncwilly The funding level was an intentional choice to make it very doable with a reasonable level of will by some entity. Indeed that was part of the consideration. A fast transit time with low residency time in system vs. a slower transit time with longer residency in system. What would the various members choose? What are the boost technologies that they would wish to use? Etc. I chose a smaller budget deliberately. Also, I gave a launch window for TACI[SUB]Trans-Alpha Centauri Injection[/SUB]. Daedalus is not feasible in that time frame. 15 years of will for the time to TACI is a sustainable level of support. 30 years until TACI is not.
In that case, I see very little point in such a mission. You claim that time to launch of 30 years is unreasonable but are not prepared to pay for a mission which could return data within the presently expected lifetime of anyone working on it, or even their grandchildren. Face it, travelling at 0.1c still takes 50 years to get there. We do not presently have any known technology which can accelerate a usefully large payload, even a one gram bullet, to that velocity. Even getting kilograms to 100km/s above solar escape velocity with available technology is hard and involved flying large rockets to within a few solar radii to get the required delta-v from a gravity assist. The rocket has to be large because around 10km/s of delta-v is required in a short time --- that's comparable with the amount to get the thing into earth orbit in the first place. 100km/s is300 times slower than 0.1c.

People have been thinking very hard about missions like this for decades. Getting anything material to α Cen within a century is hard. Getting something capable of phoning home on arrival is much harder.

Incidentally, I followed the Daedalus project when it was active and have a copy of the final report. It turns out that Alan Bond will be speaking to the local astronomical society next month so perhaps I'll ask him to sign my copy.

2012-10-22, 00:38   #8
chalsall
If I May

"Chris Halsall"
Sep 2002

2×3×1,567 Posts

Quote:
 Originally Posted by xilman In that case, I see very little point in such a mission. You claim that time to launch of 30 years is unreasonable but are not prepared to pay for a mission which could return data within the presently expected lifetime of anyone working on it, or even their grandchildren.
Why send humans to our nearest star neighbor when we already know there are no planets there to cultivate. (Unless, of course, you enjoy 1500 K weather...)

On the other hand, we have yet to live live beyond LEO for more than a few days. And it's cost us billions of dollars to run the experiments.

Perhaps we should try putting some money into living on our moon for a while. And/or, perhaps, Mars...

There might be some resources there to extract....

2012-10-22, 01:39   #9
science_man_88

"Forget I exist"
Jul 2009
Dumbassville

203008 Posts

Quote:
 Originally Posted by chalsall Why send humans to our nearest star neighbor when we already know there are no planets there to cultivate. (Unless, of course, you enjoy 1500 K weather...) On the other hand, we have yet to live live beyond LEO for more than a few days. And it's cost us billions of dollars to run the experiments. Perhaps we should try putting some money into living on our moon for a while. And/or, perhaps, Mars... There might be some resources there to extract....
using your own logic,Why send humans/robots to places beyond LEO since to my knowledge neither of those options you give are known to be able to support life at the current time.

will the nearest star system not have minerals in that planet ? if it does that could be a resource and therefore it's worth going just to extract the resources by your own logic.

2012-10-22, 01:57   #10
Dubslow

"Bunslow the Bold"
Jun 2011
40<A<43 -89<O<-88

11100001101012 Posts

Quote:
 Originally Posted by science_man_88 using your own logic,Why send humans/robots to places beyond LEO since to my knowledge neither of those options you give are known to be able to support life at the current time.
It's not that hard to build an artificial life sustaining habitat on the moon or Mars. I'd be a lot hard (read: more money and more weight) to do that in 1500K weather.

2012-10-22, 02:02   #11
chalsall
If I May

"Chris Halsall"
Sep 2002

2×3×1,567 Posts

Quote:
 Originally Posted by Dubslow It's not that hard to build an artificial life sustaining habitat on the moon or Mars. I'd be a lot hard (read: more money and more weight) to do that in 1500K weather.
You understand.

Unlike SM88.

Sadly, you both might actually be related to me....

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