Trappist-1: seven-planet resonance chain confirmed

via Tallbloke’s Talkshop
http://ift.tt/1WIzElD

Much media attention on this new paper this week. Is there a surprise lurking in the details now that the orbit period of the seventh planet has been confirmed?.

What the numbers in the diagram show is the orbits per planet in a fixed period (top row), the conjunctions per planet pair in the same period (second row), and the ratios that represents (third row).

The number of conjunctions of any two planets is the difference between the two orbit numbers in a given period, which in this case is equivalent to just under 1446 Earth days (see data below).

Apart from the obvious symmetry of the ratios, something else arose from the science paper.

It says the time taken for one rotation of the star (Trappist-1) is 3.3 days +/- 0.014 days.

Noting that the orbit numbers shown all end in 7 (77, 117 etc.) leads to a conjecture: could the number of solar rotations (sr) in the period be 437?

77 * 18.77 = 1445.29
1445.29 days / 437 sr = 3.3073 days
3.3073 – 3.3 = 0.0073 days (within the quoted margin of error from the paper)

If true: 437sr – 77h = 360 = number of b-c conjunctions in the period.
That would suggest a direct solar-planetary link in this system.

Bear in mind that all seven planets are very close to their star – much closer even than Mercury is to our Sun.