Talk:Project Longshot

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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 07:17, 17 January 2022 (UTC)

Mass ambiguity
From the article:


 * The baseline Longshot massed 6.4 metric tonnes, which includes a 3.4 tonne allocation for a large flyweel energy storage system. The rest of its mass was fuel.

Does this mean that there were 3.4 tonnes of flywheel and 3 tonnes of fuel (seems like a silly interpretation to me) or that there were 3.4 tonnes of flywheel, 3 tonnes of other equipment, and an undefined amount of fuel in addition to all that (which raises the question of what the spacecraft's full mass was)? Bryan 03:49, 21 December 2005 (UTC)


 * I agree it is very unclear what the mass of the craft would be, it states in the article that the Longshot design is somewhat similar to Project Daedalus, well that one has a mass of 54,000 tons. So "6.4 metric tonnes" seems tiny in comparison, it needs to be clarified.
 * -Hibernian 23:00, 17 July 2006 (UTC)


 * According to the PDF referenced at the end of the article, the mass of the probe inclusive of fuel is 396 metric tons. Which includes 264 tons of Helium3/Deuterium pellet fuel/propellent. the Active mission payload including fission reactor but minus main flight propulsion is 30 metric tons. - its somewhat unclear where the figure of 3.4 tons comes from to me. the instruments themselves (cameras etc) are listed as 3 tons, perhaps this is it. - the PDF is detailed and worth a read. it should be noted this design orbits within the target system unlike Daedalus which is a single flyby design. - Russell Dunwoody (17:48, 05 Sept 2006 GMT)


 * I'd tend to agree with Russell above. My own nitpick is that the speed is listed as 13411 km/s "approximately" (!) but I can't find that figure in the project PDF. On the other hand the NASA specification was for a delta-vee of about 13,500 km/s so it's about right. 203.89.168.26 (talk) 10:57, 16 May 2011 (UTC)

Note added
I added a note directly below the cited reference on this page calling attention to the fact that the article linked to contains incorrect nomenclature for the components in this star system, which might mislead the reader if they know anything about IAU nomenclature and the assigned names of stars in this constellation. I felt it was a benefit to Wikipedia users to note this, but it may require the use of proper markup. Radec (talk) 03:17, 25 September 2008 (UTC)

Cost of Fuel
Since Helium 3 is estimated to cost between $4bn and $5.6bn a ton according to several sources, that would mean that the fuel cost of the mission would be in the order of 1 to 1.5 trillion dollars. Maybe a plausability note is needed. 86.133.59.165 (talk) 16:35, 2 February 2009 (UTC)
 * Plausability note? it's just fantasy-driven speculation. It's not even well informed speculation: the authors didn't know Alpha Centauri B from Beta Centauri. Qemist (talk) 12:56, 29 March 2010 (UTC)
 * 'Plausability' [sic] derives from the calculations. These appear to be correct. In addition the PDF discusses and discards several technologies which were judged implausible (for example, lasers for a powered light sail were only able to generate such power in pulses of short duration). Of necessity they do speculate about the level of technology available by the end of the life of the Space Station, but they attempt to put clear bounds on such 'fantasy'. As for the obvious errors, you're right that the supervisors should have picked that up. Beta Centauri is well known in NASA - they called one of their staging vehicles "Agena", after all. But on the whole I've seen a lot worse in PhD theses, never mind graduate papers, than Beta Centauri for Alpha Centauri B. The students were aware of the basic parameters of what they called a "trinary system" (they included a flyby of Proxima, and a visit to both A and B). 203.89.168.26 (talk) 12:31, 16 May 2011 (UTC)

Serious?
Just a few comments and questions: Is this the only source for a project long-shot? This little homework of some sailor-students in their first semester? Correct? This is not science, this is a joke.

Has there been any research since 1988? Any further results and projects?

Perhaps one should note that in the article, that this is not a NASA-project, but a homework for students. Ugga Bugga (talk) 23:36, 4 August 2010 (UTC)


 * I've reviewed the calculations. They were carried out shortly after I received my BE from the Theoretical and Applied Mechanics department of Auckland University School of Engineering, and ten years after I completed the stage II Astronomy and Astrophysics papers at Canterbury University. As far as I can determine the only errors are typographical (terra watt for terawatt) or common errors of nomenclature (e.g. perigee for closest approach to a star, which should be periastron). No-one in the space science community blinks at such minor stuff.


 * More importantly, this was the U.S. Naval Academy's formal contribution to a NASA research requirement. The students concerned were graduate-level officer cadets (midshipmen), and according to the PDF document they were supervised by USNA faculty, as well as a NASA scientist from Goddard Space Flight Centre (Stephen Paddack, the P in YORP effect). Now THAT might be worth pointing out in the article.

--203.89.168.26 (talk) 10:48, 16 May 2011 (UTC)

Date
I think someone needs to include the year when this project was studied. —Preceding unsigned comment added by 60.242.211.37 (talk) 14:01, 15 September 2010 (UTC)

pdf 403 forbidden
The linked pdf isn't available: 403 forbidden. —Preceding unsigned comment added by 178.5.21.42 (talk) 13:48, 15 March 2011 (UTC)
 * Hm, I just downloaded it ... --203.89.168.26 (talk) 10:33, 16 May 2011 (UTC)

Poor image
I think the image currently in the article is poor and maybe should be removed or replaced. 31.18.248.254 (talk) 22:43, 2 October 2012 (UTC)
 * That image was essentially traced from the images on pages 16 and 17.--Craigboy (talk) 17:52, 29 May 2013 (UTC)