According to the universal language created by the four members of the ancient
alliance, there are 146 elements. (Torment of Tantalus)
Trinium:
Brittle in its raw state, it can be refined into a material 100 times
lighter and stronger than steel. (Spirits) The SGC used trinium
to reinforce the titanium iris over its stargate
after the original iris was sucked into a black hole. (A Matter of
Time)
Naquadah:
An element not naturally occurring in our solar system (Failsafe),
but common enough elsewhere to form the basis of a great deal of Goa'uld
technology, and eventually part of the biological Goa'uld makeup (The
First Ones). It was the element the Ancients
used to make the stargates out of.
Naquadria:
Mineral substance with highly unstable radioactive properties, with the
potential for great bursts of energy. Even a tiny amount of the mineral
emits an energy pulse greater than anything else, including weapons-grade
naquadah. This could be the missing link to discovering how to create
and maintain a hyperspace window, or to generate the sorts of shields
used by Goa'uld motherships. Discovered by the Kelownans.
(Meridian) Its instability increases exponentially as more energy
is extracted from it. (Redemption, part 1)
"Heliopolis".
The name given by Ernest Littlefield to a castle/fortress
on a world whose stargate address wasn't listed on the Abydos cartouche (and
was therefore unknown to the Goa'uld). Ernest theorized that it was a meeting
place for four ancient races to share knowledge or discuss relations, like
a "United Nations of the stars". He came to that conclusion after studying
a particular room in the castle, which had panels of writing in four distinctly
different alphabets (one clearly Asgard),
and a central energy column that when activated produced a holographic, floating
3D display of known elements (146 in this "table" -- compared with 111 for
1997 Earth, and 90 for 1945 Earth), which functioned as a basic, cross-species
basis for communication (hydrogen always consists of one proton and one electron).
That holographic display was just the first page in the "book" -- a tool to
allow anyone to "read" what else was being said: a collaboration of the knowledge
of all four races, and possibly the key to everything's existence. Given what
else is known about the earlier stages of the civilized galaxy(ies), the other
races were likely the Nox, the Furlings, and
the Ancients. The column in the middle
of the room appears to have been designed/engineered by the same race that
built the stargates and DHDs -- the Ancients. (Torment of Tantalus)
Many stargated worlds were terraformed (wow, wrong word, but that's what
Teal'c used) by the Goa'uld centuries ago -- thus all the forests and such.
(First Commandment)
The Asgard and the Goa'uld
have a treaty in place (the Protected
Planets Treaty), which currently runs to several hundred pages.
Treaty Law Section 326 recognizes that humans exist for the purpose of serving
the Goa'uld as hosts and slaves and requires that no human planet be allowed
to advance technologically to a point where they may become a threat
to the Goa'uld -- and the Goa'uld get to determine what constitutes a threat.
(Fair Game)
The Asgard part of the treaty includes
a promise to do nothing to help the people on the planets they're protecting
to advance technologically, or to artificially advance them through technological
means -- which includes using technology to save them from natural (or
unnatural) disasters. Any breach of treaty on the Asgard's part will nullify
the entire treaty, leaving all the worlds under their protection (including
Earth) open to Goa'uld attack. (Red Sky)
The Goa'uld part of the treaty includes
a promise to never attack any world under Asgard protection, on pain of
being wiped out by the Asgard. (Fair Game) The System Lords take
this threat seriously, and enforce the treaty among all Goa'uld.
The Goa'uld have broken the treaty in spirit, if not in letter,
at least twice:
Tanith (on Anubis' orders)
set up a situation where the Tollans would bomb Earth for the
Goa'uld, and was barely thwarted in this plan. (Between Two
Fires)
Some Goa'uld, probably Anubis,
sent a naquadah-heavy asteroid on a collision course with Earth,
knowing that it would destroy all life there in what would seem
to be a natural accident, whether the Tau'ri managed to plant
a nuke on it or not. (Failsafe)
The treaty provides for arbitration of
disputes. (Failsafe)
Arbitration requires a commission of inquiry, consisting of equal
numbers of Asgard and Goa'uld representatives. (Failsafe)
Also requires corroborating testimony from involved parties. (Failsafe)
If the parties aren't available (e.g., the Tollans,
after their world was destroyed), the dispute remains unresolved.
Earth has been included in this treaty
(addendum 10815 [the mind just boggles at nearly 11,000 addendums to a full
treaty...]) as of 1999. The original inclusion was going to require the
destruction of both of Earth's stargates, but after the SGC saved Cronus's
life after Nirrti's attack, that clause
was struck. Humans are safe from Goa'uld attack as long as they stay on
Earth -- but any Tau'ri caught offworld will face dire consequences, with
no repercussions from the Asgard. The Asgard,
in return for Earth's inclusion in the treaty, granted the Goa'uld
access to the Passage of Nilor.
The Aschen
have created the Aschen Confederation in their own corner of the galaxy, claiming
that all their member worlds are equals, but in fact they move in on a world,
kill off much of its population with a genetically targeted disease, kill
off much of the rest by means of virally induced sterility, and turn the remainder
into farmers to work the planet that they've plowed over and planted. Very
efficient, very creepy. (2010, 2001) They have a stargate but
no DHD and no addresses to try, so are restricted to planets within easy reach
or planets they can reach by ship. (2010) Probably caught up in their
own problems now; Jack gave them gate coordinates to the black hole after
they attempted to set up one of their "treaties" with Earth. (2010)
8,000 BC: Goa'uld are on Earth, taking personae of terran gods and harvesting
humans for hosts and slaves.
According to the movie and early episodes, this is when the Tau'ri threw
off their oppressors, throwing the Goa'uld off the planet. This is later
utterly (and ridiculously, IMO) contradicted, with the assumption that
the Goa'uld were on Earth until around the beginning of the Common Era.
(We have extensive written records for that period in the areas where
the Goa'uld appear to have been concentrated, and there's no way that
all those chroniclers would have missed such a massive event.)
ca. 700 BC: Egeria is on Earth trying to
stop Ra, and spawns the Tok'ra before she dies.
500-1000AD (?): the Asgard take some Norse to Cimmeria
to protect them; Sokar takes Europeans to
an unnamed world, posing as Satan to force them to do his bidding.
This century: rediscovery of and reactivation of the stargate; humans from
Earth start heading out into the galaxy, disturbing the balance of power.
To use an eighth chevron
(which seems to be a galaxy code), a stargate needs 10 times as much power
as it does normally (The Fifth Race)
Safety protocols:
the stargate system has safety protocols and protections built into it,
to prevent connections that will do dangerous things, like dumping unstable
isotopes into a primary. (Red Sky)
Another safety protocol is designed to keep energy signatures from
mixing together; one way the gate does this is to erase the energy
buffer (the memory of energy signatures stored in its crystals) every
time a new wormhole engages. (48 Hours)
Physical structure:
Made of naquadah,
which has a decay rate of 150 years (used for dating) (A
Hundred Days).
Weigh 64,000 pounds. (Redemption, part 2)
The gate element is a superconductor that absorbs energy in many forms.
It converts and stores energy in reservoirs, making it possible to unlock
and spin the mechanism manually when enough power is stored. (Torment
of Tantalus)
Stargates can draw power directly from a source
at the far end of the wormhole, making it impossible to disconnect the
gate from the point of origin (A Matter of Time, Watergate).
Drawing power from the other end of the wormhole seems to negate the 38-minute
window.
If a stargate's energy-absorption capacity is exceeded, the naquadah
the gate is made of could become charged and explode, in a tremendous
blast: 2,000-3,000 megatons, with environmental effects that could wipe
out all life on a planet. (Redemption, part 1)
Wormholes:
First-season (Solitudes) theoretical explanation of the stargate
wormhole: The gate is a giant superconductor that creates an artificial
wormhole that transfers an energized matter stream in one direction along
an extra-dimensional conduit. A power overload, possibly from enemy fire,
caused a malfunction, redirecting the energy stream to the second earth
gate.
To keep a wormhole open, you have to send something through, even if
it's just a radio wave. (Redemption, part 1)
Ordinarily, a wormhole will close within a short period if nothing enters
it. (Redemption, part 1)
A wormhole can be maintained for 38 minutes. (There But for the Grace
of God, Serpent's Song)
If the stargate is being powered by an alternate
source, a wormhole can remain open longer (A Matter of Time,
Watergate)
Explanations of wormhole physics:
A stargate cannot activate when buried, but it can engage under
water. (Watergate)
The wormhole only allows matter to travel
one way, but radio signals can be transmitted both ways. (Watergate)
The gate has the ability to use density, molecular structure, and
the force being exerted on the event horizon to determine whether
something is trying to pass through. (Watergate)
The alpha gate supersedes the beta gate as long as the DHD is connected.
If it is connected only when in use, it will prevent crossover to
the beta gate. (Watergate)
The stargate on the receiving end
of a wormhole temorarily stores the energy signature of each object
passing through the wormhole before reforming the object, to be sure
that it has all the necessary information. Reintegration of the object
clears the signature, as does a new wormhole engaging (incoming or
outgoing). (48 Hours)
Cutting off power to an outgoing wormhole prematurely can trap
objects withing the stargate system as energy, if the stargate
on the receiving end doesn't have enough time to recreate the
object. (48 Hours)
The signature is stored not in the energy itself, but is imprinted
on the crystals in the receiving stargate, to be held in "memory"
until the object is reformed. (48 Hours)
If an object is trapped, it is lost completely the next time
a wormhole engages, clearing/erasing the "buffer". The
only way to reintegrate it is to remove the DHD's master control
crystal before attaching the DHD. (48 Hours)
Removal of the master control crystal could result in massive
uncontrolled energy flows -- and if stray current goes into
the wrong conduit, the entire stargate could explode. (48
Hours)
Dialing:
Most addresses consist of six points and a point
of origin, but it's possible to use seven points and a point of origin
(The Fifth Race). There's room on the stargate for nine chevrons,
but no more than eight have ever been used.
The unique symbol on a gate is its point
of origin.
Stargates can be used on a ship, but only if that ship is in orbit around
a planet with a known address or point of origin, so the DHD can be properly
dialled. A ship in transit can't use a stargate. (Within the Serpent's
Grasp)
DHDs compensate for stellar drift without
the operator needing to worry about it. (2001)
Without a DHD or some other way to compensate for stellar drift, Sam
believes that a gate can only be dialled to other gates within a 300-light-year
radius. (2001)
Can be dialled without a DHD or other dialing
device; all it needs is enough power hooked up to the ring, and to be
moved manually. Two truck engines is sufficient. (1969) A directed
lightning strike will also work, although it risks overloading the gate
mechanism. (Torment of Tantalus)
The stargate can emit up to 400 feedback
signals during the dialing process (tied in to the system's safety
protocols?) (48 Hours)
