Limits of amateur photometry in detecting exoplanet transits?

[malclocke (Malc)]

Hi all,

I'm wondering if anyone would have an idea of the limits of photometric sensitivity of a competent amateur in terms of detecting an exoplanet? More specifically, would an amateur be capable of detecting a 0.5% drop in flux from an ~ mag 15 star?

The reason I ask is that a while ago a posted on a thread (http://www.iceinspace.com.au/forum/s...d.php?t=101591) that I had been presented with a potential exoplanet while using the Planet Hunters website. Confirmation of the exoplanet would rely on a third transit being detected in Nov 2013 by the Kepler Space Telescope. Given the precipitous condition of Kepler, this seems unlikely to happen.

I'm just wondering if it's worth pursuing the idea of asking for help from earth bound amateurs to detect this transit, but have no idea if this is within the realms detection.

Malc

[LAW (Murphy)]

[EDIT] iPhone finger stutter.

[LAW (Murphy)]

http://youtu.be/iXKTz0I2X84

These guys don't seem to be using anything out of the reach of amateurs. However confirmation is a big step up from possible detection.

[malclocke (Malc)]

Thanks Murphy, that's encouraging.

The WASP discoveries seem to have host stars ranging from vmag 8 to 12. That's encouraging, as they don't know there targets when searching. Although my star is considerably dimmer, I know exactly where and when to look.

The next question is who's arm do I twist in the northern hemisphere to get them to do a load of photometry a nobody in New Zealand November night

[robin_astro]

Hi Malc,

Off the top of my head I think 5 millimag precision on a mag 15 star might be quite tough for an amateur. A starting point could be the signal/noise calculator here
http://stupendous.rit.edu/richmond/signal.shtml
But there are several other limiting factors (and tricks of the trade) to this sort of transit detection work. I would suggest contacting Bruce Gary who is a (the?) top amateur expert on transit detection.
http://brucegary.net/

Cheers
Robin

[lepton3 (Ivan)]

Hi Malc,

I know this is beyond my equipment and skill. But maybe not beyond the capabilities of the very best amateurs with serious equipment.

I worked with Bruce Gary on the White Dwarf Exoplanet survey in 2011. I could achieve 5 mmag precision on a 13 Mag target. A 15 Mag target is more like 50 - 100 mmag scatter for me. This is with a C11 and Atik 320E CCD.

The guys at Mt John in NZ got < 1 mmag on the same target using a 24 inch scope + Apogee Alta U47 camera. So a setup like that in similar hands might just do it for a 15 Mag target.

There is some interesting info, including a list of skilled observers who participated, at the PAWM website http://brucegary.net/WDE/. There were many N.H. guys involved.

-Ivan

[pdalek (Patrick)]

Hi,

Take a look at Project PANOPTES (Panoptic Astronomical Networked OPtical observatory for Transiting Exoplanets Survey)
http://projectpanoptes.org/v1/

[malclocke (Malc)]

Thanks everybody for the info.

I contacted Bruce Gary, it turns out he is running a campaign for amateurs to follow up on the Kepler candidates, see http://brucegary.net/kafo/

I've sent Bruce the details of a few candidates from Planet Hunters which were not on his list, hopefully they will be of use.