Moons: 0 traces of hydrogen and helium basaltic and anorthositic rocks and regolith
Mercury is the first planet from the Sun. Mercury's elliptical orbit takes the small planet as close as 46 million km and as far as 70 million km from the Sun. Temperatures on Mercury's surface can reach 430 degrees Celsius. Because the planet has no atmosphere to retain that heat, nighttime temperatures on the surface can drop to -170 degrees Celsius.