4 ms·
Kepler uses occlusion, not wobbling.
by schiffern 14y ago
Kepler uses occlusion, not wobbling.
- Udo 14y agoStill, a very rare event requiring a precise alignment of the star system that gets more improbable and more rare the further out a planet is. And I imagine we need 2-3 data points of transitions at least to exclude false positives - that simply doesn't happen within a reasonable time (e.g. Neptune has an orbital period of 165 years).
- teamonkey 14y agoYes, and it's designed to detect Earth-sized planets as well as larger gas giants.
- Tuna-Fish 14y agoBut detection probability is directly correlated to planet size and shortness of the local year. Eventually, Kepler and Kepler-like probes will be able to locate all earth-like planets with orbits that cross the path between the star and us. However, this technique will find the larger planets with shorter orbits first.
- teamonkey 14y agoYes indeed, but the point is that according to current theories Kepler should already be finding more Earth-sized planets than it has and few inner gas giants. The observable evidence does not match the predicted model.
- Retric 14y agoCan detect is one thing, can detect at the same distance is another. Assume you can detect an earth like planet at say 100 light years and a Jupiter sized planet at 1,000 light years and you find 1000x as many Jupiter sized planets that does not mean there are 1,000x as many just that you can detect them in 1,000x as much space. Granted I don't know there search pattern but we are talking about less than 1,000 systems at this point. And I think we have found 2 reasonably earth like planets already which suggests there are at a minimum millions of them in this galaxy.
- lutorm 14y agoTrue, but occultations are also very biased towards planets with small semimajor axis, because the solid angle that produces an occultation goes roughly as 1/a.
- schiffern 14y agoYou use "but" as though you're disputing some statement I made, when I intentionally avoided making any statement outside my knowledge. I said Kepler does use occlusion, and does not use wobbling. I'm not trying to single you out here. I'm just curious what one has to say on HN so as not to be corrected. Is there some "don't assume I've implicitly made a bunch of unsupported remarks" initialism that I can tack on to the end of all my posts? /DAIIMABOUR
- dandelany 14y agoNo need to get defensive, lutorm was just pointing out that the assumption made by the OP is still supported. His comment was simply a productive, interesting addition to yours, unlike this complaint.
- fusiongyro 14y agoI'm glad he brought it up. I have noticed it is getting awfully hard to say anything precisely enough to get it past the cadre of pedants.
- cmccabe 14y agoActually, the correct expression is "cohort of pedants."
- fusiongyro 14y agoAre these tears of laughter or rage?