![]() ![]() The apparent size is nearly the same as that of the Sun, allowing it to cover the Sun almost completely during a total solar eclipse. This is mainly due to its large angular diameter, while the reflectance of the lunar surface is comparable to that of asphalt. ![]() The Moon is the brightest celestial object in Earth's night sky. The Moon is, beside when passing through Earth's shadow during a lunar eclipse, always illuminated by the Sun, but from Earth the visible illumination shifts during its orbit, producing the lunar phases. ![]() These maria formed when large impacts on the far side of the Moon heated up low lying layers of its crust on the near side. The lunar surface is covered in impact craters and is marked, mostly on the near side of the Moon, by dark maria ("seas"), which are plains of cooled magma. It formed 4.51 billion years ago, not long after Earth's formation, out of the debris from a giant impact between Earth and a hypothesized Mars-sized body called Theia. The body of the Moon is differentiated and terrestrial, with no significant hydrosphere, atmosphere, or magnetic field. Its diameter is 3,474 km (2,159 mi), which is roughly one-quarter that of Earth or about the width of Australia, making it the largest and most massive satellite in the Solar System in relation to its parent planet and the fifth-largest Solar System satellite overall. It is a satellite planet in geophysical terms and among all planetary-mass objects of the Solar System larger and more massive than all of its known dwarf planets. The Moon's mass is about 1.2% of Earth's its density and surface gravity (at 0.1654 g) are rivaled among Solar System satellites only by Jupiter's moon Io. Exerting gravitational force on Earth, it and to a lesser extent the Sun are the main drivers of the tides. This results in the lunar month of 29.5 days matching the lunar day. It always faces Earth with its near side, being tidally locked to Earth. It orbits at an average distance of 384 400 km ( 238 900 mi), about 30 times the planet's diameter. The Moon is Earth's only natural satellite. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |