Kepler-441 b: A 207.25 days Year
Super-earth around Kepler-441
It is 1.64 times Earth's radius, closest in size to Earth. A year there lasts 207.25 days, on an orbit 1.7 times Mercury's distance from the Sun. Its equilibrium temperature is 177 K (derived from the star rather than measured), colder than anywhere on Earth. The host star Kepler-441 runs at 4340 K with 0.57 times the Sun's mass.
Radius
1.64 Earth radii
Equilibrium temperature
177 K (derived)
One year
207.25 days
Orbit radius
0.6400 AU
Host star
Kepler-441 at 4340 K
Distance
874 light-years
Starlight blocked
0.075% at each transit
What you get from the shadow
The depth of the dip is the ratio of the two discs, so the radius follows.
The habitability checklist, honestly scored
Within the zone where liquid water could persist. No.
A measured mass, not just a radius. No.
A measured temperature rather than one derived from the star. No.
Any detection of an atmosphere. Not recorded in the archive.
The archive lists no measured equilibrium temperature for this planet. The 177 K quoted here is derived from the star's output and the orbital distance, assuming a third of the light is reflected. It is an estimate from two numbers, not an observation.
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.
Found by Kepler in 2015. Kepler's method needed repetition, not brightness. It could find small planets around faint stars, provided they came round quickly enough to be seen twice.
Half the temperatures quoted for exoplanets are calculated from the star, not \
measured at the planet. Should a page like this show them at all, or leave the field blank?
