tag:blogger.com,1999:blog-10448119.post8410110536687518060..comments2024-03-23T06:42:53.608-04:00Comments on Hogg's Research: extreme precision radial velocitiesHogghttp://www.blogger.com/profile/18398397408280534592noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-10448119.post-11899108636716734192016-05-26T11:11:13.003-04:002016-05-26T11:11:13.003-04:00A slightly clunkier term, which I think is still b...A slightly clunkier term, which I think is still better than "transmission spectroscopy", is "transit radius spectroscopy". The advantage of this term is that it's very close to being what is *actually* measured. We have no idea which photos were transmitted through the planet's atmosphere and therefore no way to take a spectrum of those photons. What we do is measure the transit radius of the planet as a function of wavelength.Dave Spiegelhttps://www.blogger.com/profile/01007092170683109822noreply@blogger.comtag:blogger.com,1999:blog-10448119.post-33227696918609169402016-05-25T16:41:45.058-04:002016-05-25T16:41:45.058-04:00How do you distinguish between a spectrum of a sta...How do you distinguish between a spectrum of a star that is in transit from a spectrum that *does* contain information about the atmosphere? You could have a transit spectrum with no information about the atmosphere; that doesn't convey what I intend to convey, which is the change to the spectrum caused by having some of the light passing through the exoplanet atmosphere.Hogghttps://www.blogger.com/profile/18398397408280534592noreply@blogger.comtag:blogger.com,1999:blog-10448119.post-76274689300908944202016-05-25T16:27:10.350-04:002016-05-25T16:27:10.350-04:00Thought it's a losing battle, I fight it nonet...Thought it's a losing battle, I fight it nonetheless:<br /><br />We shouldn't call it "transmission spectroscopy". Transmission spectroscopy is when you have an absorption cell, and every photo the comes out the other side has been transmitted through the cell.<br /><br />In *transit spectroscopy*, 99% of the photons (in the case of a Jupiter — more otherwise) didn't touch the planet at all. Of those that did touch the planet, nearly all of them were entirely blocked by the planet. The fraction of photons that were transmitted through the thin patina of atmosphere is nearly zero.Dave Spiegelhttps://www.blogger.com/profile/01007092170683109822noreply@blogger.com