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> Unlike most planets in the Solar System, HD 20794 d’s orbit is not circular but elliptical Kepler's First Law says otherwise.
by strictnein 2y ago
> Unlike most planets in the Solar System, HD 20794 d’s orbit is not circular but elliptical
Kepler's First Law says otherwise.
- ceejayoz 2y agoIt has an eccentricity of 0.40 (https://en.wikipedia.org/wiki/82_G._Eridani https://en.wikipedia.org/wiki/82_G._Eridani). That's about twice as eccentric as Pluto/Mercury; Earth's is 0.016. It's a reasonable layperson-friendly summary of the situation.
- close04 2y agoThe orbits of planets in our solar system are quasi-circular, with only Mercury (e=0.20) and Mars (e=0.09) being more elliptical. Every other planetary orbit in our solar system has e<0.05, even 0.00x for Venus or Neptune. They're not perfect circles but close enough for all practical purposes.