Karl Grossman is continuing his ignorant jeremiad against nuclear power in space, including RTGs:
Last month, Japan launched what it called its “space yacht” which is now heading to Venus propelled by solar sails utilizing ionized particles emitted by the Sun.
When he writes stuff like this (light sails are propelled by photons, not “ionized particles”), why should we take anything else he writes (like all of the people who died of radiation poisoning from the SNAP 9A entry) seriously? He’s just a journalism professor.
I have to admit, though, it’s kind of amusing that this will be one more thing for the Left to be disappointed about in Obama.
Um, news alert, there is, in fact, a solar wind composed of ionized atoms/molecules which does, in fact, impart a greater amount of force than solar light pressure. This was proven back when Jack Eddy was still trying to convince people of the existence of the Maunder Minimum.
Of course there’s a solar wind. But it’s not what propels light sails. They are propelled by radiation pressure.
Ok, wikipedia (http://en.wikipedia.org/wiki/Solar_sail) says both propel solar sails, but the radiation pressure is significantly greater than the solar wind.
The radiation pressure of sunlight is about 10,000 times greater than the dynamic pressure of the solar wind.
Hmmm… why is it that this Karl Grossman “article” reminds me of the “stupid minds” scene from Plan 9?
But we can’t have radiation in space [hands waving in terror.]
The problem with the solar wind, in addition to its weakness, is that it isn’t consistent in direction and strength, so it’s more like atmospheric winds.
Actually, it’s weakness sounds like a good thing considering inconstancy. Would it make navigation difficult?
The counterintuitive thing about this is that saying radiation pressure is greater than solar wind is like saying an angry stare is more forceful than a good shove. After all, we’re all taught that photons have no mass, their force only comes from the relativistic translation of their energy into mass.
I guess he was hoist by a solar petard.
After all, we’re all taught that photons have no mass, their force only comes from the relativistic translation of their energy into mass.
I don’t know about you, but that’s not what I was taught.
They have no rest mass. They have plenty of momentum.
Doesn’t mention that solar panels are useless for most functions beyond Mars-NASA’s proposed Juno probe to Jupiter uses solar panels, but it’s not doing video or still photagraphy. I believe the Solar VASIMIR is just designed as a transfer vehicle from Earth orbit to lunar orbit. But there’s another ideological, and perhaps even subconcious reason for Grossy’s opposition to space n-power. A functioning nuclear-powered VASIMIR would open up the Solar System to practical exploitation. This would mean the evil, nasty capitalists spilling off into space and spreading out so much that they would be impossible to control. In the long run this would mean the permanent defeat of the welfare-state mentality, and the end of lefty dreams of social control.
Mike Gallagher
Seoul, Korea
PS: Dear Mr. Simberg. I have to take exception to your crack about journalism majors, and its implied criticism of most non-tech majors. We’re not all like that. I’m an English teacher working in Seoul and I know better than Grossy, You just have to take a real interest and not brainlessly adopt the conventional wisdom.
My favorite nuclear rocket is still the Orion project from the late fifties. Oh how I wish there was never an atmospheric test ban treaty.
I wonder what the Banana equivalent dose http://en.wikipedia.org/wiki/Banana_equivalent_dose from the SNAP 9A entry was.
Jardinero1, solar sails have a huge advantage of no fuel needed.
I’m surprised good ole Bruce Gagnon hasn’t thrown his 2 cents worth in on this… /Sarcasm
I’m surprised good ole Bruce Gagnon hasn’t thrown his 2 cents worth in on this
Actually, if you read the article, the moron did. The author even cited him.
He also mentioned the late Dr. John Gofman, who made significant contributions to nuclear science as a young man, but who also spent much of his life promoting the idea that radiation damage to human tissues was linearly accumulative over one’s life and that there was no safe minimum radiation dose. Predictions based on Gofman’s ideas have been repeatedly shown to be erroneous by orders of magnitude. The anti-nukey-kookies refuse to dismount this particular hobbyhorse no matter how often it fails to run. Grossman’s article is nonsense, to be sure, but at least, in good enviro style, it’s recycled nonsense.
Citing Brce Gagnon as an authority on space power issues is like citing Woody Allen as an expert on Quantum Computing.
But in the sliders universe, he is.
IIRC Compton proved that photons have momentum in an experiment during the early XXth century. I remember that from college physics. Photons can behave both like waves and particles.
Citing Brce Gagnon as an authority on space power issues is like citing Woody Allen as an expert on Quantum Computing.
Amen to that…