Search found 34 matches

by Rick Kwan
Wed Sep 15, 2010 1:58 am
Forum: Awareness
Topic: Washington Post article: miniature nuclear reactors
Replies: 1
Views: 11110

Washington Post article: miniature nuclear reactors

There's an article in the on-line Washington Post titled: Miniature nuclear reactors might be a safe, efficient source of power by Brian Palmer, Tuesday, Sept. 14, 2010. It's all about fission reactors making a comeback. http://www.washingtonpost.com/wp-dyn/content/article/2010/09/13/AR2010091304026...
by Rick Kwan
Fri Jan 08, 2010 10:05 pm
Forum: General
Topic: Russia may send spacecraft to knock away asteroid
Replies: 25
Views: 9837

But to me, any potentially impacting asteroid is also a potential candidate for mining. You already have an Earth fly-by. You need a delta-V to effect a rendezvous, and then enough energy to take it apart so that the pieces can be refined... somewhere... I second that! Wonder if an terrestrial mini...
by Rick Kwan
Wed Jan 06, 2010 8:32 pm
Forum: General
Topic: Russia may send spacecraft to knock away asteroid
Replies: 25
Views: 9837

Damage goes as the cube root of energy. So it is not as bad as it seems. Even if it goes as the square root of energy (detonation at optimum height) it takes 100X as much energy to get 10X the damage. Thanks for the insight. I presume the cube root is related to volume (rather than my naive linear)...
by Rick Kwan
Wed Jan 06, 2010 12:06 pm
Forum: General
Topic: Russia may send spacecraft to knock away asteroid
Replies: 25
Views: 9837

A while back, I tried to do some comparisons to grasp the magnitude of an Apophis impact. It turned out to be a really hard thing to grasp just because of the magnitude. Here are estimates I see from Wikipedia and other sources, given in terms of megatons of TNT (MT). * 0.012-0.022 MT -- atomic bomb...
by Rick Kwan
Sun Jul 12, 2009 4:01 pm
Forum: Fund-Raising
Topic: Charles Bolden's friend
Replies: 1
Views: 11245

Some alert reader decided to transcribe the portion of the comfirmation hearing where Bolden made this comment. It turns out his friend is former astronaut Franklin Chang-Diaz, and the system is definitely VASIMR. http://www.spacepolitics.com/2009/07/09/passing-the-audition/ I believe flight test of...
by Rick Kwan
Sat Jul 11, 2009 8:16 pm
Forum: Fund-Raising
Topic: Charles Bolden's friend
Replies: 1
Views: 11245

Charles Bolden's friend

Paragraph below is taken from the article "Chalie Bolden's vision for NASA" http://blogs.nature.com/news/thegreatbeyond/2009/07/charlie_boldens_vision_for_nas.html Third, Bolden said that NASA had to make space exploration more entrepreneurial. He cited the example of a friend who was using venture ...
by Rick Kwan
Mon Jun 01, 2009 12:55 pm
Forum: Implications
Topic: Project Icarus: Son of Daedalus
Replies: 0
Views: 3575

Project Icarus: Son of Daedalus

It appears that the British Interplanetary Society (BIS) and the Tau Zero Foundation foundation has kicked off a follow-on study to Project Daedelus, which examined a fly-by of Barnard's Star back in the 1970s. BIS page: http://www.bis-spaceflight.com/sitesia.aspx/page/1964/l/ Tau Zero page: http://...
by Rick Kwan
Fri May 15, 2009 2:58 am
Forum: Awareness
Topic: ACES 2009 language needs to include polywell -- URGENT!
Replies: 29
Views: 23632

I would not seed language in the ACES act, which seems to be aimed at alternative energy deployment. Before you get the people at large to want it, you need to get the science and engineering community educated and backing it; I don't think we're there yet. If there were a bill about energy research...
by Rick Kwan
Mon May 11, 2009 2:22 pm
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

I think Rick means one of these: http://nextbigfuture.com/2007/11/fusion-propulsion-if-bussard-iec-fusion.html I almost forgot about Tom's ISDC presentation. I'm sure he interprets the data better than I do. I think the first slide on that page sums up the booster scenario: * specific impulse: 1538...
by Rick Kwan
Mon May 11, 2009 6:31 am
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

Aaaand it looks like someone has already patented my idea for an MHD turbine on the back end of a scramjet. Darn... You mean this thing? " Magnetogasdynamic Power Extraction and Flow Conditioning for a Gas Turbine " http://gltrs.grc.nasa.gov/cgi-bin/GLTRS/browse.pl?2003/TM-2003-212612.html It's lat...
by Rick Kwan
Mon May 11, 2009 4:30 am
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

By the way, to me, 11,800,000 m/s is a really awesome exhaust velocity. (1/25 * light speed :wink: )
by Rick Kwan
Mon May 11, 2009 4:25 am
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

* I recall something in one of the QED papers about specific impulse of 1500 seconds on the low end. (My notes say: "Inertial-Electrostatic-Fusion Propulsion Spectrum: Air-Breathing to Interstellar Flight", Bussard and Jameson, AIAA Journal of Propulsion and Power, March-April 1995 vol.11 no.2 (pp....
by Rick Kwan
Mon May 11, 2009 4:15 am
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

You could use something heavier (methane? water?) with a lower exhaust velocity and get the same momentum. But then you need more of it, mass-wise. This is the whole reason they use LOX/LH2 in the first place. You could use something heavy at the same exhaust velocity, and not have to deal with hug...
by Rick Kwan
Mon May 11, 2009 2:52 am
Forum: Theory
Topic: polywell reactor for booster rocket applications?
Replies: 60
Views: 33585

But doesn't the space shuttle main engines have a thrust to weight ratio (shuttle and full tank included) less than 1? I know is this from a while back, but I didn't see any clarification... so here goes... Scanning some Wikipedia pages, the Space Shuttle thrust/weight ratio is 6.78 million lbf / 4...
by Rick Kwan
Mon May 11, 2009 1:53 am
Forum: Awareness
Topic: ACES 2009 language needs to include polywell -- URGENT!
Replies: 29
Views: 23632

Something that worked well for the Mars rovers: instead of building a single rover as original ly proposed, two were built at the same time. This allowed the construction of the rovers to be used to validate each other, and quite likely improved the changes of mission success. Now, admittedly the ro...