Point of origin

From SGCommand

The point of origin is a symbol neccessary for the dialing of Stargate addresses. While the first six symbols represent constellations indicating a point in space, this seventh point indicates where the wormhole is coming from.

For years, Earth's point of origin was unknown, as the Egyptians had placed two figures praying by the symbol of the pyramid. Daniel Jackson eventually recognized the mistake, and the Tau'ri were able to link to Abydos. (Stargate)

As part of a personal preference, when the point of origin hits the seventh chevron, Walter Harriman will announce "chevron seven locked", as a way to change things up. (SG1: "Children of the Gods", "Heroes")

[edit] Known points of origin

Abydos's point of origin	Chulak's point of origin	Earth's Alpha Gate point of origin (Brought by Ra, unknown original whereabouts)	Earth's Beta Gate point of origin (Original Terra stargate left by Lanteans)
Icarus Base's point of origin	Klorel's ha'tak point of origin	Lantea's point of origin	Medieval planet's point of origin
Melia's point of origin	Pangar's point of origin	P2X-416's point of origin	P34-353J's point of origin
P3R-233's point of origin	P3X-562's point of origin	P4M-328's point of origin	P7J-989's point of origin
P7S-441's point of origin	Tagrea's point of origin	Tollan's point of origin	Destiny's point of origin

[edit] Behind the scenes

After arriving on Abydos in 1994 in the feature film, Daniel Jackson had difficulty locating the planet's point of origin, despite that it would be the only different symbol on the gate. This can be contributed to differences between the film and series. In the movie, the Abydos Stargate had different glyphs than Earth's while in the series, all Stargates in the same galaxy have the same glyphs except for their unique point of origin.