Find the forbidden planets

1 · Say what is forbidden

Beginner

Why are these three planets "forbidden"?

Their stars are too young to have planets They are too massive to orbit a giant Their orbit is smaller than the maximum radius their star once reached

2 · Place HD 12648 b

24 Boo b completes an orbit in 30.3 days, at 0.183 au from a star of 0.88 solar masses. HD 12648 b takes 132.9 days around a star of 1.03 solar masses. Kepler's third law: a³ is proportional to M × P².

Intermediate

About how far from its star is HD 12648 b?

About 0.18 au About 0.52 au About 0.80 au

3 · Explain the role of asteroseismology

Expert

Why did the team need the oscillations of the stars?

To tell a giant on its way up from a red-clump giant To measure the orbital periods of the planets To find the tilt of the orbits, hence the exact masses of the planets

4 · Find the most fragile planet

The team compares each orbit with the maximum radius of the star, computed for several convection settings and several compositions.

Expert

For which planet does the verdict depend most on the convection model?

24 Boo b TYC 4282-605-1 b HD 12648 b

Planets found

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