M54

M54 or M-54 may be:

Roads:

Vehicles:

Astronomy:

M54 (truck)

The M54 Truck (G744) was a 5-ton 6×6 U.S. military heavy cargo truck. A member of the M39 series, it was designed to transport a 5-ton (10,000 lb (4,500 kg)), 7 ft (2.1 m) wide, and 14 ft (4.3 m) long cargo load off-road in all weather. In on-road service the load weight was doubled.

The M54 was the primary heavy truck of the U.S. Army and U.S. Marine forces during the Vietnam War, and was also used by the U.S. Navy, U.S. Air Force, and ARVN forces.

The M54 began to be replaced by the M939 in 1982, but continues to serve in other nations' armed forces around the world.

History

The M39 (G744) series was designed as a 5-ton (4536 kg) three axle all wheel drive off road truck to replace World War II era trucks such as 4 and 6 ton 6x6’s built by Brockway, Diamond T, Mack, and White. Rushed into production by International Harvester in 1951, soon Kaiser (renamed Kaiser-Jeep in 1963) also became a major manufacturer, with Diamond T and Mack building smaller numbers. The M39 series evolved into the M809 (G908) series in 1969, which followed, but did not replace, it. The M809 Series was then improved into the M939 series.

Messier 54

Messier 54 (also known as M54 or NGC 6715) is a globular cluster in the constellation Sagittarius. It was discovered by Charles Messier in 1778 and subsequently included in his catalog of comet-like objects.

Previously thought to belong to our galaxy at a distance from Earth of about 50,000 light-years, it was discovered in 1994 that M54 most likely belongs to the Sagittarius Dwarf Elliptical Galaxy (SagDEG), making it the first globular cluster formerly thought to be part of our galaxy reassigned to extragalactic status, even if not recognized as such for nearly two and a quarter centuries.

Modern estimates now place M54 at a distance of some 87,000 light-years, translating into a true radius of 150 light-years across. It is one of the denser of the globulars, being of class III (I being densest and XII being the least dense). It shines with the luminosity of roughly 850,000 times that of the Sun and has an absolute magnitude of −10.0.

As it is located on SagDEG's center, some authors think it actually may be its core; however others have proposed that it is a real globular cluster that fell to the center of this galaxy due to decay of its orbit caused by dynamical friction.