In this case, the planet is low mass but very close in. The Doppler shift in the starlight amounts to a mere half meter per second – slower than walking speed! When I read that I was stunned; that low of a signal is incredibly hard to detect. Heck, the star’s rotation is three times that big. But looking at the paper, it’s pretty convincing. They did a fantastic job teasing that out of the noise.The graph displayed shows the effect of the planet on the star. RV means "radial velocity", the speed toward and away from us as the star gets tugged by the planet. The x-axis is time, measured in units of the period of the planet (in other words, where it reads as 1 that means 3.24 days). The dots look like they’re just scattered around, but when you average them together – say, taking all the dots in a one hour time period – you get the red dots shown (the vertical lines are the error bars). The signal then pops right out, and you can see the tell-tale sine wave of a planet pulling its star.
This blog exists purely as a place for me to dump random links and thoughts I have rather than emailing them to my friends. It'll have large amounts of inside jokes. Also there will probably be times when I write "you" or refer to an email. Just pretend that you are reading an email to you. If you don't know me you likely won't find anything here interesting. If you do know me you also will not find anything here interesting.
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