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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How I Think We’ll Discover Alien Life on Other Planets
September 25th, 2008
This is my opinion. I like to think it’s well-informed as an astronomer and science fiction novelist who spends way too much time thinking about such issues, but the fact is we’re too ignorant on this topic to speak with a lot of authority.
If nothing is there, we won’t find anything, for instance.
But let me tell you how we can be pretty sure of identifying life-bearing worlds if they’re not too uncommon, and how we can do it within our lifetimes, or sooner.
Life changes things. Oxygen in atmospheres should not be common without life. It may or may not be life as we know it, but oxygen is a pretty handy molecule for life to exploit and produce, even if it’s poison to creatures that develop in reducing atmospheres. Change the environment, life evolves.
So, an oxygen atmosphere is a sign of life. Not necessarily intelligent life.
Next step is to continue finding exoplanets, especially eclipsing exoplanets. Surveys are underway. The signal from an Earthlike body will be less than a percent, and it would be nice to identify some systems having larger planets eclipsing, too, first.
Then we make a more difficult observation: spectroscopy. Molecular oxygen has very strong absorption at around 582 nm and 786 nm (I’ve even seen it in spectra taken inside a telescope dome looking through very little air).
If we see those absorption bands, which we seen in ground-based spectra and label “telluric” (from the Earth), then we know we’ve found something. I bet the next step is a giant interferometer in space to image the sucker. Lights on the nightside would be likely proof of intelligent/civilized life.
This technology and plan is all feasible and the timescale is decades, given the will and the money.
If Earthlike planets with life are common enough, it will even work, although it will take some luck to find observable systems and pull it off.
And I remember not so long ago when I was in grad school that the existence of exoplanets was a big question mark. I may live long enough to have this fundamental question, is there alien life in the universe, answered.
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Mike: while spectroscopy of exoplanets to look for oxygen and water bands is perfectly feasible, and not that far in the future (see Webster Cash’s work on the “star shade” for example), seeing cities on the dark side of planets isn’t. Think about how FAINT cities are, at all wavelengths, compared to the background ….It’s the equivalent of imaging a 50th magnitude star (actually, MUCH worse than this)! No amount of integration time is going to be sufficient. The best that we’re likely to be capable of (outside of using the sun as a gravitational lens) is to do spatially resolved spectroscopy of continents and oceans, which is damned good, of course, and easily good enough to detect life on the earth at interstellar distances.
Yeah, Harold, you’re probably right about that. Theoretically possible, probably not practical for a long, long time to come. What is much more feasible would be spectroscopic detection of the lights if they’re a particular type, e.g., sodium. That would be a much more detectable signal, although I am not going to do the calculation to figure out how much more detectable. If we find an eclipsing planet with an oxygen atmosphere, I feel certain we’ll spend a lot of time and money to observe it in great, great detail. And there will be intense SETI efforts and arguments about whether to send our own signals their way, whether or not we detect any from there.