:INFO
Terrestrial around Kepler-879
It is 0.40 times Earth's radius, closest in size to Mars. A year there lasts 15.5 hours. The host star Kepler-879 runs at 5457 K with 0.97 times the Sun's mass.

:STATS
[icon:TARGET] Radius | 0.40 Earth radii
[icon:CLOCK] One year | 15.5 hours
[icon:STAR] Host star | Kepler-879 at 5457 K
[icon:USERS] Distance | 2618 light-years
[icon:TRENDING_DOWN] Starlight blocked | 0.001% at each transit

:PATH
What you get from the shadow
Block a known fraction of a known star and you have measured a width.

:COUNTER
15.5 hours: one full year, start to finish

:TIMELINE
🔭🪐📅
2016-01-01 | Kepler-879 b
2024-01-01 | Kepler-879 c

:CHECKLIST
What has been measured here and what has not
[ ] A radius from transit photometry. Yes.
[ ] A mass. No.
[ ] A density, the one clue to composition. No.
[ ] How far out it orbits. No.
[ ] A temperature someone observed rather than calculated. No.
[ ] An eccentricity, so we know if the orbit is a circle. No.

:NOTE
Kepler-879 has 2 known planets. Planets in company tug on each other, and those tugs are measurable, which is how masses get pinned down without a wobble.

:NOTE
Found by watching its star dim as it crossed in front. That measures size and not weight, which is why there is a radius here and no mass.

:NOTE
Found by Kepler in 2024. The mission traded sky coverage for depth, holding one view for years. That bias runs through its whole catalogue and through this planet's discovery.

:LINK
https://exoplanetarchive.ipac.caltech.edu/overview/Kepler-879%20c
NASA Exoplanet Archive: the full record for Kepler-879 c