Comment by 7373737373 | Hacker News Reader

Comment by 7373737373 | Hacker News Reader

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I have no idea how, and would like to know.

It may be that these are stars with smaller diameters, so the smaller planets occlude a larger fraction compared to sun-like stars.

Otherwise I suspect the required hardware is likely out of reach for amateurs with current technology.

Edit: Found these: https://en.wikipedia.org/wiki/MEarth_Project

> The MEarth Project is a United States NSF-funded, robotic observatory that is part of Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona, US. The project monitors the brightness of thousands of red dwarf stars with the goal of finding transiting planets. As red dwarf stars are small, any transiting planet blocks a larger proportion of starlight than transits around a Sun-like star would. This allows smaller planets to be detected through ground-based observations.

https://www.eso.org/public/teles-instr/paranal-observatory/s...

> The mission for SPECULOOS is to detect terrestrial planets as they transit across small, cool stars in the solar neighbourhood

It seems the terrestrial planets https://en.wikipedia.org/wiki/TRAPPIST detected are also around dwarf stars.

So I guess the summary is: finding and detecting earth-like planets around dwarf stars is possible, however around sun-like stars not quite yet using these two methods

Yeah, I was going to say it's probably to do with "sun-like" and angular size ratios. (I'm not religious, but the sun and the moon being the same angular size has always felt like an easter egg that a creator might leave as a bit of fun).

Sun-like is important in the search for life because despite putting out lots more energy, the suspicion is that yellow stars tend to be less temperamental in their flare behavior (so they don't scour the surface of any potential planets with large amounts of radiation every once in awhile). And there is evidence that our sun is even a particularly calm yellow star. The habitable zone is also in a region that doesn't tidally lock the planet; a day-night cycle seems important though not neccesarily a requirement for habitability. And yellow stars' lifecycle seems to be long enough to allow for life to form and evolve. Essentially they seem most likely to produce habitable planets - it's probably not mere happenstance that we live around one.

How often is the bucket filled during the transit? Noise in each emptying will average out, so a dip could be detected even if the dip in a single reading of the bucket could not be.

Typical transits last a few hours, and exposures times are typically a few minutes. So you have up to hundreds of exposures per transit. I guess how "statistically recoverable" this data is depends beside the resolution also on the noise level. The atmosphere introduces a lot of variability in ground-based observations, and a star's brightness is not constant either.

https://astronomy.stackexchange.com/questions/51679/feasibil...

I suppose it depends how regular the signal is otherwise. If a dip happens super-regularly (which I guess it would with single star planet orbits), it might be small relative to pointwise noise of the detector, but large enough to be detected over time (if you have the observations).

Your point on period length stands. And anyway I'm just waxing lyrical, I'm a statistician and amateur stargazer not a pro :)

Damn those are some good names

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