Full moon is a lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. More precisely, a full moon occurs when the geocentric apparent (ecliptic) longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun.

Lunar eclipses can only occur at full moon, where the moon's orbit allows it to pass through the Earth's shadow. Lunar eclipses do not occur every month because the moon usually passes above or below the Earth's shadow (which is mostly restricted to the ecliptic plane). Lunar eclipses can occur only when the full moon occurs near the two nodes of the orbit, either the ascending or descending node. This causes eclipses to only occur about every 6 months, and often 2 weeks before or after a solar eclipse at new moon at the opposite node.

As seen from Earth, the hemisphere of the Moon that is facing the Earth (the near side) is almost fully illuminated by the Sun and appears round. Only during a full moon is the opposite hemisphere of the Moon, which is not visible from Earth (the far side), completely unilluminated.

Sonata Arctica is a Finnish power metal band from the town of Kemi, originally assembled in 1995. Their later works (most notably The Days of Grays, Unia and a few tracks on Reckoning Night and Winterheart's Guild) contain several elements typical of progressive metal.

The band was founded by Marko Paasikoski, Jani Liimatainen and Tommy Portimo in Kemi at the end of 1995 (Tony Kakko and Pentti Peura joined in early 1996). Originally named Tricky Beans, they played hard rock rather than the power metal with which they grew to fame. During their early career, they recorded three demos which were never sent to any recording label — Friend 'till the End, Agre Pamppers and PeaceMaker.

In 1997 the band changed their name to Tricky Means, and from that point until 1999 their style was thoroughly worked upon and ultimately was drastically changed, acquiring strong emphasis on the keyboard melodies and relying on an easily distinguishable rhythm line maintained both by the bass and the guitar. Vocalist Tony Kakko developed a clean singing style which relies both on falsetto and tenor voices and second guitarist Marko Paasikoski left the band. Kakko has stated that the change of sound was influenced by fellow Finnish power metal band Stratovarius.