Mudstone for silt (63 μm). On December 13, 2016, NASA reported further evidence supporting habitability on the planet Mars as the "Curiosity" rover climbed higher, studying younger layers, on Mount Sharp. Also reported, the very soluble element boron was detected for the first time on Mars. In June 2018, NASA reported that "Curiosity" had detected kerogen and other complex organic compounds from mudstone rocks approximately 3.5 billion years old. Mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Grain size is up to with individual grains too small to be distinguished without
Gliese 687 40% of the Sun's mass and nearly 50% of the Sun's radius. Compared to the Sun, it has a slightly higher proportion of elements with higher atomic numbers than helium. It appears to have a rotation of 60 days and to be somewhat chromospherically active. It displays no excess of infrared radiation that would indicate orbiting dust. It is known to have a planet, Gliese 687 b, with a mass of 18.394 Earth masses (which makes it comparable to Neptune), an orbital period of 38.14 days, and a low orbital eccentricity. Gliese 687 is a solitary red dwarf that emits