The most widely accepted origin explanation posits that the Moon formed 4.51 billion years ago, not long after Earth, out of the debris from a giant impact between the planet and a hypothesized Mars-sized body called Theia. However, 59% of the total lunar surface can be seen from Earth through shifts in perspective due to libration.
The Moon is tidally locked to Earth, which means that the length of a full rotation of the Moon on its own axis causes its same side ( the near side) to always face Earth, and the somewhat longer lunar day is the same as the synodic period. During each synodic period of 29.5 days, the amount of visible surface illuminated by the Sun varies from none up to 100%, resulting in lunar phases that form the basis for the months of a lunar calendar. The Moon's orbit around Earth has a sidereal period of 27.3 days.
Orbiting Earth at an average distance of 384,400 km (238,900 mi), or about 30 times Earth's diameter, its gravitational influence very slowly lengthens Earth's day and is the main driver of Earth's tides. Jupiter's moon Io is the only satellite in the Solar System known to have a higher surface gravity and density. Its surface gravity is about one-sixth of Earth's ( 0.1654 g). It lacks any significant atmosphere, hydrosphere, or magnetic field. The Moon is a planetary-mass object that formed a differentiated rocky body, making it a satellite planet under the geophysical definitions of the term. In the Solar System it is the fifth largest satellite, larger than any of the known dwarf planets and the largest (and most massive) satellite of a planet relative to the planet. It is about one-quarter of Earth in diameter (comparable to the width of Australia). Together with Earth it forms the Earth–Moon satellite system. Continued abuse of our services will cause your IP address to be blocked indefinitely.The Moon is Earth's only natural satellite. Please fill out the CAPTCHA below and then click the button to indicate that you agree to these terms. If you wish to be unblocked, you must agree that you will take immediate steps to rectify this issue. If you do not understand what is causing this behavior, please contact us here. If you promise to stop (by clicking the Agree button below), we'll unblock your connection for now, but we will immediately re-block it if we detect additional bad behavior. Overusing our search engine with a very large number of searches in a very short amount of time.Using a badly configured (or badly written) browser add-on for blocking content.Running a "scraper" or "downloader" program that either does not identify itself or uses fake headers to elude detection.Using a script or add-on that scans GameFAQs for box and screen images (such as an emulator front-end), while overloading our search engine.There is no official GameFAQs app, and we do not support nor have any contact with the makers of these unofficial apps. Continued use of these apps may cause your IP to be blocked indefinitely. This triggers our anti-spambot measures, which are designed to stop automated systems from flooding the site with traffic. Some unofficial phone apps appear to be using GameFAQs as a back-end, but they do not behave like a real web browser does.Using GameFAQs regularly with these browsers can cause temporary and even permanent IP blocks due to these additional requests. If you are using Maxthon or Brave as a browser, or have installed the Ghostery add-on, you should know that these programs send extra traffic to our servers for every page on the site that you browse.The most common causes of this issue are: Your IP address has been temporarily blocked due to a large number of HTTP requests.