Comments on: parallel observing http://oklo.org/2009/12/13/parallel-observing/ characterizing planetary systems Fri, 18 Nov 2011 22:27:52 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: greg http://oklo.org/2009/12/13/parallel-observing/comment-page-1/#comment-33433 greg Wed, 16 Dec 2009 06:22:50 +0000 http://oklo.org/?p=746#comment-33433 The errors are due in part to atmospheric scintillation, and errors from this source _will_ go down by root N. Remember too, that for a nominal detection, the 0.0005 mag precision need apply only to the full transit duration relative to the out-of-transit baseline. It doesn't need to apply with the cadence shown in Brat's plot above. Short-period planets that transit do so with with independently known clockwork regularity, so there is ample opportunity (at zero cost to the taxpayers) for confirmation if a marginal signal is detected. Photometry of 0.47 millimagnitude per-sample photometry with a cadence of 1.3 minutes from the ground has already been demonstrated, and so I'm not sure that 0.5 mmag photometry at, say 30-min cadence by skilled amateurs is necessarily a "forlorn hope". The errors are due in part to atmospheric scintillation, and errors from this source _will_ go down by root N. Remember too, that for a nominal detection, the 0.0005 mag precision need apply only to the full transit duration relative to the out-of-transit baseline. It doesn’t need to apply with the cadence shown in Brat’s plot above. Short-period planets that transit do so with with independently known clockwork regularity, so there is ample opportunity (at zero cost to the taxpayers) for confirmation if a marginal signal is detected.

Photometry of 0.47 millimagnitude per-sample photometry with a cadence of 1.3 minutes from the ground has already been demonstrated, and so I’m not sure that 0.5 mmag photometry at, say 30-min cadence by skilled amateurs is necessarily a “forlorn hope”.

]]> By: coolstar http://oklo.org/2009/12/13/parallel-observing/comment-page-1/#comment-33428 coolstar Tue, 15 Dec 2009 20:42:08 +0000 http://oklo.org/?p=746#comment-33428 Sorry, but to me just seems like a forlorn hope, in the extreme. Photometry of better than 0.0005 mag rms from the ground? You know that these errors are NOT dominated by photon noise, so why do you think the errors will go down by root N, as you implied? guess I'm majorly confused. Sorry, but to me just seems like a forlorn hope, in the extreme. Photometry of better than 0.0005 mag rms from the ground? You know that these errors are NOT dominated by photon noise, so why do you think the errors will go down by root N, as you implied? guess I’m majorly confused.

]]> By: gregas http://oklo.org/2009/12/13/parallel-observing/comment-page-1/#comment-33415 gregas Mon, 14 Dec 2009 17:11:33 +0000 http://oklo.org/?p=746#comment-33415 Interesting idea Greg, it reminds me when I started to image with a bad mount without guiding and had to stack 100 10s subframes to have an image. It may work! Joao Gregorio Interesting idea Greg, it reminds me when I started to image with a bad mount without guiding and had to stack 100 10s subframes to have an image. It may work!

Joao Gregorio

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