A4

A4 and variants may refer to:

Science and mathematics

Medicine

Transportation

Aeronautics and astronautics

Douglas A-4 Skyhawk

The Douglas A-4 Skyhawk is a single seat carrier-capable attack aircraft developed for the United States Navy and United States Marine Corps. The delta winged, single-engined Skyhawk was designed and produced by Douglas Aircraft Company, and later by McDonnell Douglas. It was originally designated A4D under the U.S. Navy's pre-1962 designation system.

The Skyhawk is a lightweight aircraft with a maximum takeoff weight of 24,500 pounds (11,100 kg) and has a top speed of more than 670 miles per hour (1,080 km/h). The aircraft's five hardpoints support a variety of missiles, bombs and other munitions. It was capable of carrying a bomb load equivalent to that of a World War II-vintage Boeing B-17 bomber, and could deliver nuclear weapons using a low altitude bombing system and a "loft" delivery technique. The A-4 was originally powered by the Wright J65 turbojet engine; from the A-4E onwards, the Pratt & Whitney J52 was used.

Skyhawks played key roles in the Vietnam War, the Yom Kippur War, and the Falklands War. Sixty years after the aircraft's first flight, some of the nearly 3,000 produced remain in service with several air arms around the world, including from the Brazilian Navy's aircraft carrier, São Paulo.

Luigi's Mansion

Luigi's Mansion (ルイージマンション, Ruīji Manshon, "Luigi Mansion") is an action-adventure game published by Nintendo for the GameCube. It was the first game in the Mario franchise to be released for GameCube. It was released in Japan on September 14, 2001, in North America on November 18, 2001, and in Europe on May 3, 2002. The game was a launch title for the GameCube, and the second title in the Mario franchise where Luigi is the main character, instead of Mario, the first, third, fourth and fifth being Mario is Missing!, Luigi's Mansion: Dark Moon, "New Super Luigi U" and Dr. Luigi, respectively.

The game takes place in a haunted mansion when Luigi wins a contest that he never entered. He told his brother to investigate. Luigi is searching for his brother, Mario, who came to the mansion earlier, but went missing. To help Luigi on his quest, an old scientist named Elvin Gadd or E. Gadd has equipped him with the "Poltergust 3000", a vacuum cleaner used for capturing ghosts, and a "Game Boy Horror", a device used for communicating with E. Gadd. He also uses it as a map and to examine ghosts.

Dark moon

A dark moon describes the Moon during that time that it is invisible against the backdrop of the Sun in the sky. The duration of a dark moon is between 1.5 and 3.5 days, depending on the orientation of the Earth and Sun.

In astronomical usage, the new moon occurs in the middle of this period [source?], when the moon and sun are in conjunction. This definition has entered popular usage, so that calendars will typically indicate the date of the "new moon" rather than the "dark moon". However, originally "new moon" referred to the crescent on the first night it is visible, one or two days after conjunction. Maritime records from the nineteenth century distinguish the dark moon (no moon) from the new moon.

Dark Moon as the 30th Division

The Oxford English Dictionary defines the new moon as “the first visible crescent of the Moon, after conjunction with the Sun”. Dark Moon is a term used for a waning crescent. When the Moon is divided into 30 portions as the ancient Greeks did in the time of Homer, the Babylonians did, and the Indians still do till today (calling them tithi), the last phase of the Moon is called the Dark Moon. In Greek it was called the Old Moon and associated with Hecate. In India it is called Amavasya and associated with Kali. Both of these goddesses have a Dark connotation, hence the Dark Moon.

Luigi's Mansion: Dark Moon

Luigi's Mansion: Dark Moon, known in Japan as Luigi Mansion 2 (ルイージマンション2, Ruīji Manshon Tsū), and in Europe, Australia and Hong Kong as Luigi's Mansion 2, is an action-adventure video game developed by Next Level Games and published by Nintendo for the Nintendo 3DS, and is the sequel to the 2001 game Luigi's Mansion for the Nintendo GameCube. The game was first released in Japan on March 20, 2013, and in most other major regions later that same month. It is the third Mario game where Luigi is the protagonist, after Mario Is Missing and the original Luigi's Mansion.

In Dark Moon, the player takes control of the Mario franchise character Luigi, who is equipped with the Poltergust 5000, a specialized vacuum cleaner used to capture ghosts. In the game's single-player mode, the main goal is to retrieve the pieces of the shattered Dark Moon, a magical object that has a pacifying effect on the ghosts residing in the game's setting, Evershade Valley, by seeking them out in the five haunted mansions located therein. Dark Moon offers a cooperative multiplayer mode that can be played locally or online via Nintendo Network.