Following the discovery of Kepler-10c, previous analysis from the HARPS-North data in 2014 estimated a mass above 17 earths, making it a shocking find, but then in 2017, further and improved analysis from the HIRES data showed that its mass and density are much lower, at no more than 7.37 Earth masses and a mean density of only 3.14 g/cm3, making it a mini-neptune.
Despite the recent find, several other planets are believed to be mega earths based on current analysis.
K2-38b is said to have a mass nearly 12x that of Earth, and a radius of only 1.527x that, putting the density to an astounding 17.5 gm/cm3, making it perhaps the densest planet known.
https://arxiv.org/abs/1511.09213https://arxiv.org/archive/astro-ph.EPK2-56b, a.k.a. BD+20594b is said to have a mass of 16.33 earths and a radius of 2.23x that.
K2-66b is currently analysed to have a mass of 21.3x that of Earth's, and a radius of 2.49x that.
Kepler-145b is said to be 37.1x as massive as Earth, with a radius reaching 2.65x that, therefore based on current analysis, it's now crowned the king of the terrestrials and the true godzilla of earths.
https://arxiv.org/abs/1601.07608Though unfortunately, the star Kepler-145's radius hasn't been measured to this day by any analysis and US2 renders it as a yellow subgiant, so we'll wait and see what the analysis measures the star's true size to be.
https://www.hou.usra.edu/meetings/lpsc2018/pdf/1224.pdfMega earths are defined to be planets with a terrestrial/rocky composition with a mass of 10 earths or greater, and they're amongst the densest exoplanets ever known.
Topic: Mega Earths (Read 4102 times)
