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Several Extrasolar Planets May Be Optical Illusions
person-0.9a writes "Seems that a few of the extrasolar planets detected via their sun's wobble might be written off according to a CNN article. You can also read it about it in New Scientist."
An astronomy prof described astronomy as that in a frosh astro course. In particular, we were discussing methods of determining stellar distance. For stars fairly close we use an ultra reliable method called paralactic displacement. For methods beyond that, we start using methods that basically say "as long as our theories about how such and such behaves turn out to be true, this method of determining stellar distance should hold true."
This article just goes to show how fragile human knowledge is. But this is a good thing, and part of the natural progression of science.
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
It seems strange to me that the reason the planets were found not to exist is because the sunspots on the surface of the star somehow masqueraded as doppler shifts, thereby creating the illusion that a doppler spectroscopy observation had found a planet. This is the scenario that both news sources allude to. It seems much more likely that the giant sunspot would fool an astronomer using the so called transit photometry method of planet detection, whereby the transit of a planet in front of the stars disk dimms it slightly, having the same effect that a large sunspot would as it traverses the rotating stars viewable surface. Can anyone who knows more about this story explain what really happened?
- "Hear that?! The percolations are imminent! Cease your ingress!"
Unfortunately this is only one of many "hot Jupiters" as they're called. The prevalence of these odd planets is primarily due to an observation bias, as our method of detection is only sensitive to large-mass objects close to a star. Thus, when you look, and see a lot of "hot Jupiters", go fig, that's all you could detect.
Giant planets with orbital radii 1 AU are not, however, completely impossible to understand. The current theory is that they form out beyond the ice-condensation point (this is what allows gas giants to balloon to such a huge size/mass), and then some mechanism forces them to slowly migrate inward toward the star. They've managed to do this in simulations, however, it's not a wonderfully good explanation. It doesn't, after all, explain why Jupiter is where it is for us.