Spider Star
The human colony on the planet Argo has long explored and exploited the technology left behind by an extinct alien race. But then an archaeology team accidentally activates a terrible weapon...
Read More.Praise for Star Dragon
"Seldom does a storytelling talent come along as potent and fully mature as Mike Brotherton. His complex characters take you on a voyage that is both fiercely credible and astonishingly imaginative. This is Science Fiction."
-- David Brin"Star Dragon is terrific fare, offering readers a fusion of hard science and grand adventure."
-- Locus Magazine"Star Dragon is steeped in cosmology, the physics of interstellar travel, exobiology, artificial intelligence, bioscience. Brotherton, author of many scientific articles in refereed journals, has written a dramatic, provocative, utterly convincing hard science sf novel that includes an ironic twist that fans will love."
-- Booklist starred review"Readers hungry for the thought-provoking extrapolation and rigorous technical detail of old-fashioned hard SF are sure to enjoy astronomer Brotherton's first novel."
-- Publishers Weekly"Mike Brotherton, himself a trained astrophysicist, combines the technical acuity and ingenuity of Robert Forward with the ironic, postmodern stance and style of M. John Harrison. In this, his debut novel, those twin talents unite to produce a work that is involving on any number of levels. It's just about all you could ask for in a hardcore SF adventure."
-- Paul di Fillippo, SCI-FI.COM
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ROY G BIV
May 27th, 2008
My mother is reading Spider Star and liking it significantly more than Star Dragon, primarily because she feels more for the characters. She hasn’t finished the book yet, but did tell me on the phone the other day that she’d noticed an error. Not a typo, but an outright mistake.
She claimed I’d gotten the temperature sequence of the colors of the rainbow incorrect. The mnemonic “ROY G BIV” describes the sequence, running from red through orange, yellow, green, blue, indigo, and violet.
She was wrong, but it was a reminder for me about communicating science that is second nature to me and how easy it is to forget the general audience. Let’s talk about the specific instance in Spider Star. It’s in regard to the color of stars, and their temperatures, as they evolve. Hotter stars are bluer, while cooler stars are redder.
To most people, red is a warm color, while blue is a cool color. Warm stoves glow red, after all, and icy things and cool water look blue or bluish. Artists think this way, very much, as do those in fashion and decorating. But this is completely backwards to an astrophysicist.
Blue photons have higher frequencies and energies than red photons. When you heat a dense gas, as in the atmosphere of a star, it does warm up and glow red. If you continue to increase the temperature, the gas will put off a higher fraction of higher energy photons. At some point it will be “white hot” when it’s emitting a lot of visible light at all wavelengths (remember color wheels and how mixing all the colors gives you white). Continuing to heat the gas will give you a blue tint.
An aside: these points also explain why there are no green stars. When you heat something to a temperature such that the peak photon energies correspond to green light, intermediate between red and blue energies, there is enough light at all visible wavelengths that the star will appear white. With good eyes/telescopes, you can see stars in the sky that appear red, white, and blue, but never green.
The technical term for how hot dense gases, solids, and liquids radiate as a function of temperature is blackbody radiation, although I always hated the term because radiating objects sure don’t look black, do they? Anyway, the wiki link just above goes into more detail for those interested, plotting actual spectra.
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