The planet’s orbit has to be oriented pretty close to edge-on, and the transit has to be deep enough, and the period has short enough to see multiple transits, and – well you get the idea. Even if all stars have a planet, many things have to be just right to detect transits. The KELT planet survey observes several hundred thousand stars in search of transits. So within a reasonable survey duration I would be able to cover only several hundred stars. Only about 10 to 20 stars in each field were bright enough to search for transits. Then repeat for the next couple of years. To have a reasonable chance, I’d have to observe the same fields for months, until Earth in its glide about the sun turns its night face towards other star-fields. I soon got worried about mechanical wear – it’s an off-the-shelf beast and not the world’s most robust telescope.Ī transit needs to be recorded at least 3 times in order to confirm that the signal repeats at a particular period. This was a lot of moving around (re-pointing) for the telescope. Each field contained at least one of my 371 target stars. PEST spent the first few months of its existence looking at about 5 different star fields each night, cycling through each in turn. I compiled a list of target stars of brightness between mag 7 to 12 – bright enough to allow good precision, but not to saturate the CCD. ![]() ![]() The original search strategy was to look for transit signals around nearby stars. The probability that a given star has a transiting planet is pretty small And because these planets would be mine – all mine – I would be able to call them PEST-1b etc.
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