The Asgard are a highly advanced, fictional extraterrestrial race in the science fiction series Stargate SG-1 and Stargate Atlantis. They are first mentioned in the episode "Thor's Hammer", and first seen in "Thor's Chariot". In the series, the Asgard gave rise to Norse mythology on Earth, as well as accounts of the Roswell "Greys". Due to their technological prowess, the Asgard are critical allies in Earth's fight against the Goa'uld, and later the Ori. The Asgard characters on the show are realized through a combination of puppets and computer-generated imagery.
The episode "The Fifth Race" establishes that the Asgard inhabit the galaxy of Ida, and that they were once part of an alliance of four great races with the Ancients, Nox, and Furlings. In ancient times, the Asgard visited Earth, posing as the gods of Norse mythology. Norse legends tell of how they protected the humans against the "Etins" (Goa'uld). The Asgard protect a number of planets in the Milky Way from Goa'uld attack under the Protected Planets Treaty. In the time of Stargate SG-1, the Asgard are a dying race. Having lost the capacity for sexual reproduction, they perpetuate themselves by transferring their minds into successive cloned bodies. Repeated generations of cloning has led to an irreversible degeneration of the Asgard genome. A 30,000-year-old Asgard ancestor is depicted in "Revelations", showing a more human-like appearance.
Their physical appearance is like the conventional Grey alien. An incident in Stargate SG-1 (season_4) episode 1 when Samantha "Sam" Carter, joyful after a victory over the Replicators, hugs Thor, shows that the Asgard are physically fragile; luckily no harm resulted.
 Show history
In the tenth episode of season 1, "Thor's Hammer", Daniel Jackson speculates on the existence of an advanced, benevolent race in opposition to the Goa'uld by examining Earth mythologies. This leads SG-1 to the planet Cimmeria, which is free from the Goa'uld thanks to an advanced device called "Thor's Hammer". SG-1 makes direct contact with Thor in "Thor's Chariot", sixth episode of season 2, in which his true Asgard form is seen for the first time. The Asgard lend valuable assistance to Earth on several occasions, including providing their technology to Earth ships. In the episode "Fair Game", where Thor mediates Earth's inclusion into the Protected Planets Treaty, he reveals to Jack O'Neill that the Asgard do not have the capability to win a galactic war with the Goa'uld at that time, due to a war with a greater enemy. The Goa'uld Anubis ultimately nullifies the treaty after developing shields resistant to Asgard weapons. After Anubis' defeat in "Lost City", there is speculation amongst the Goa'uld System Lords that the Asgard are no longer able to exercise power in the Milky Way.
At the end of season 3, the Asgard's enemy is revealed to be the Replicators, a race of machines capable of assimilating any technology they come across. In the episodes "Nemesis" and "Small Victories", they are on the verge of overrunning the Asgard homeworld. Thor enlists SG-1's help in combating them, as "crude" human projectile firearms are effective against the Replicators, and the technologically-minded Asgard are incapable of developing unorthodox (i.e. "less sophisticated") strategies like humans can. With Samantha Carter's help, the Replicator invasion force is destroyed. In "Unnatural Selection", the Asgard reveal that using the android Reese, discovered by SG-1 in "Menace", they lured every Replicator in the galaxy to the planet Halla with the hopes of trapping them inside a time dilation field. SG-1 activates the field, but the Replicators eventually escape in "New Order" and head for the planet Orilla, where the Asgard are rebuilding their civilization. The Replicators retreat from the Asgard galaxy after Thor finds specifications for the Replicator disruptor from O'Neill's mind. When the Replicators arrive in the Milky Way in "Gemini" and "Reckoning", Thor helps the SGC develop an effective defense.
After the end of the Replicator threat, the Asgard install significant upgrades in Earth's new battlecruiser, Daedalus, and stationed an Asgard engineer, Hermiod, on board to oversee the new technology. The Asgard Kvasir provides assistance to Earth in "Ripple Effect", "Camelot", and "Flesh and Blood", stating that Thor and Heimdall are otherwise engaged in another galaxy. In the Stargate SG-1 finale "Unending", Thor reveals that the Asgard have been afflicted by a rapid degenerative disease due to repeated cloning. Unable to Ascend due to their seeking a technological solution to extending their lives, there is nothing more that can be done and most of the Asgard civilization elects to self-destruct to prevent their technology from falling into the wrong hands. As their final act, the Asgard install their latest technology on the Earth battlecruiser Odyssey, as well as their entire collected knowledge. The Asgard homeworld Orilla explodes just as the Odyssey comes under Ori attack.
A renegade faction of Asgard is introduced in the fifth season of Stargate Atlantis. These Asgard splintered from the others 10,000 years ago over their belief that they should experiment on humans to solve their cloning problems. They traveled to the Pegasus galaxy and continued their experiments, but were forced into hiding after the Wraith defeated the Ancients. When their planet became too toxic for them, they unsuccessfully tried to use the Attero Device to destroy the Wraith.
The governing body of the Asgard is the High Council, shown in "Red Sky". It has at least seven members, including Thor, Freyr, and Penegal. The Asgard masquerade themselves holographically as Norse gods to the primitive peoples under their protection. They have placed tests, such as in the Hall of Thor's Might on Cimmeria, to determine when those peoples have advanced enough for the Asgard to reveal their true forms.
 Protected Planets Treaty
The Protected Planets Treaty is an armistice between the Goa'uld and the Asgard, first referred to specifically in "Fair Game" when Earth is included. The treaty covers 27 planets including Earth, and ensures that those planets remain free from Goa'uld domination. Other planets in the treaty include Cimmeria, K'Tau, PX3-595, the second planet of the Adara system, and Galar. The System Lords are responsible for enforcing the treaty amongst the lesser Goa'uld. One stipulation of the treaty is that none of the protected planets are allowed to advance to the point of posing a threat to the Goa'uld; the System Lords cite this condition in their original demand that Earth surrender its Stargate to be included in the treaty. Another term of the treaty is that the Asgard are forbidden to artificially advance the civilization of any protected planet, even to save them from a natural disaster. This prevents them from acting to help K'Tau in "Red Sky" and Earth in "Fail Safe". Any violation of the treaty will nullify it as a whole, and free the Goa'uld to attack any protected planet.
The Asgard rely on the treaty to do what good they can in the Milky Way, using the threat of their superior technology to cow the System Lords into accepting the arrangement when, in fact, their resources are taxed fighting the Replicators and they would be unable to win a full-scale war with the Goa'uld. The treaty becomes largely irrelevant after the season 5 finale "Revelations", due to the actions of Anubis, although Thor destroys a Hatak on its way in season 8, when the System Lords attempt to negotiate access to Earth's Antarctica defense system.
The Asgard are one of the most technologically advanced races in the Stargate universe. They were once contemporaries of the Ancients, and learned much from them. Amongst their most significant advancements are beaming technology, intergalactic hyperdrives, and plasma beam weapons, all of which they have shared with Earth. The Asgard are no longer capable of sexual reproduction and instead perpetuate themselves through cloning, as they have the technology to upload and store Asgard consciousnesses and transfer them to new bodies. Neutronium is a key element of Asgard technology. Technology is a central aspect of Asgard civilization; they have become so dependent on it that their mindsets are incapable of coming up with more "primitive" solutions to a problem. This weakness proved critical in their war with the Replicators.
The Asgard's military technology is, with a few exceptions, largely superior to that of the Goa'uld, Wraith and even Ori and Lantian period Asuran war ships. Their directed plasma beam weapons are highly effective against nearly all kinds of shields. In addition, Asgard shields are shown to take large amounts of damage from Ori, Wraith, Goa'uld and Ancient weapons. They also appear to be the only shields effective against Ancient drone weapons known to penetrate nearly all other kinds of shields including Ancient shields. However, Asgard shields apparently lose integrity under sustained fire.
Hermiod, named after the Norse god Hermóðr and voiced by Trevor Devall, is an Asgard technician assigned to the Daedalus. He is tasked with operation of the ship's Asgard transporter and hyperdrive engine, working primarily with Lindsey Novak. Hermiod mutters to himself when he is displeased with the crew's demands, although his Asgard language is actually normal English played backward. The producers gave him "a little bit of an attitude problem", being an angry foreigner utterly convinced of his own brilliance above those around him.
Hermiod is introduced during the Daedalus' first mission to Atlantis in "The Siege, Part 3". Hermiod expresses resistance to carry out Colonel Steven Caldwell's order to transport several nuclear weapons on board a Wraith hive ship because the Asgard prohibit humans from using the shared Asgard technology offensively, but he later reluctantly agrees to do as ordered. Hermiod helps remove a Wraith computer virus that interferes with the ship's computer systems in "The Intruder", and works with Dr. McKay on the Wraith technology during Atlantis' failed alliance with a Wraith Hive-Ship.
Supreme Commander Thor, voiced by Michael Shanks, is the Supreme Commander of the Asgard Fleet. SG-1 first encounter him as a Viking holographic recording (played by Mark Gibbon) on the planet Cimmeria in "Thor's Hammer". They meet the real Thor one season later when he saves Cimmeria from Heru-ur's invasion. After O'Neill manages to make friendly contact with the Asgard in their galaxy, Thor includes Earth in the Protected Planets Treaty to safeguard it from a direct Goa'uld attack. Late in season 3, SG-1 helps to destroy Thor's ship, the Beliskner, which has been overtaken by the Replicators, in "Nemesis". Impressed by SG-1's primitive but effective tactics, Thor requests SG-1 to help fight the Replicators in his Asgard homeworld soon after, in "Small Victories". Anubis captures Thor and probes his mind for Asgard technology, and Thor's body lapses into a coma in "Revelations". SG-1 retrieve Thor's consciousness from the ship's database a while later, and transfer it into a new body.
Thor asks for SG-1's assistance after his people's plan to trap the Replicators inside a time-dilation field on the planet Halla backfired. Thor personally makes an appearance at a secret meeting between the permanent members of Earth's UN Security Council taking place in the Pentagon, to ensure the SGC retains control over the Earth Stargate. As the time-dilation device on Halla cannot keep the Replicators bottled up forever, Thor collapses Halla's sun into a black hole, but some Replicators escape. Some weeks later, Thor and Carter modify their Replicator Disruptor, but as the Replicators quickly adapt, they use the Dakara Superweapon to destroy all Replicators in one strike. Thor gets a new clone body soon after. Thor summons the Odyssey to the Asgard homeworld Orilla and installs the entire knowledge base of the Asgard race on the ship. As attempts to save the Asgard civilization from their genetic difficulties have failed, he informs Lt. Col. Carter that the people of Earth are the fifth race and makes it their turn to preserve the future. Thor perishes along with the rest of the Asgard race when their planet self-destructs before the Ori can attack.
Six puppeteers were necessary to make the different parts of the Thor puppet work. Thor originally speaks slower in the first season, but Michael Shanks, who voiced him since the beginning, joked that he is not getting paid by the hour but by the amount of dialog, when commenting on the increased dialog speed in later episodes. As the Thor puppet is neither able to walk nor stand, the puppet is often put in a chair.
 Minor characters
- Aegir (voiced by Michael Shanks, who also plays Dr. Daniel Jackson) The commander of a small fleet of ships that protects Orilla in "New Order", named after the Norse god Aegir. He destroys Fifth's Replicator ship as it exits hyperspace, but cannot stop massive numbers of Replicator blocks from raining down on Orilla.
- Freyr (voiced by Brian Jensen) A member of the Asgard High Council, named after Freyr, the Norse fertility god and god of love. SG-1 first encounters him on K'Tau, an Asgard protected planet. Freyr is also initially presented through a Viking hologram. Freyr refuses to help SG-1 because it would be a violation of the Protected Planets Treaty. SG-1 meets Freyr and the Asgard High Council again to save Earth from an approaching asteroid, but get no help. Freyr eventually requests SG-1 to rescue one of their scientists. He protects SG-1, the Asgard scientist Heimdall and his studies with a fleet of three O'Neill class battleships.
- Heimdall (voiced by Teryl Rothery, who also played Dr. Janet Fraiser) An Asgard scientist based on the Heimdallr of Norse mythology. SG-1 encounters Heimdall in "Revelations" during his research into finding a solution to the Asgard's cloning difficulties. When the Goa'uld attack Heimdall's planet, SG-1 and Heimdall flee together with the saved Thor and Heimdall's research. Heimdall continues to look for a solution to the flawed genome with Thor, but the Asgard race existing within the galaxy of Ida dies at the end of season 10, unaware of the renegade faction existing within the Pegasus Galaxy introduced in the Stargate Atlantis episode 'The Lost Tribe'.
- Kvasir (voiced by Morris Chapdelaine) An Asgard scientist and expert in time-dilation technology. He is named after Kvasir, a Norse god and wisest of the Vanir. As Thor is busy in the Asgard home galaxy in "Ripple Effect", Kvasir visits Earth in Thor's stead to help Earth fix a problem with alternate realities. Kvasir also assists SG-1 in battling the Ori at the end of season 9 of SG-1. Kvasir survives the battle and helps to repair the transporters of the Odyssey.
- Loki (voiced by Peter DeLuise) A rogue Asgard scientist working to find a cure for his species' genomic decay. He is based on Loki, the Norse god of mischief. His unauthorized experiments on Earth humans have inspired many accounts of alien abductions. In "Fragile Balance", he is responsible for creating the younger clone of Jack O'Neill as a side product of his studies on O'Neill's brain. At the end of the episode, Thor, visibly angry at Loki's actions takes Loki into custody.
- Penegal (voiced by Michael Shanks) A member of the Asgard High Council in "New Order, Part II". He informs Thor of the Replicators's attack on Orilla.
 See also
- "Thor's Hammer" (Stargate SG-1)
- "Fair Game" (Stargate SG-1)
- "Revelations" (Stargate SG-1)
- "The Fifth Race" (Stargate SG-1)
- "Disclosure" (Stargate SG-1)
- "New Order" (Stargate SG-1)
- "Nemesis" (Stargate SG-1)
- "Small Victories" (Stargate SG-1)
- "The Siege, Part 3" (Stargate Atlantis)
- The Lost Tribe
- "Red Sky" (Stargate SG-1)
- "Thor's Chariot" (Stargate SG-1)
- "Shades of Grey" (Stargate SG-1)
- "Collateral Damage" (Stargate SG-1)
- "Stargate Atlantis: Season Two Preview". TV Zone Special #64 (Visual Imagination). 2005. pp. 76–77.
- "The Siege, Part 3" (Stargate Atlantis)
- "The Intruder" (Stargate Atlantis)
- "Allies" (Stargate Atlantis)
- "Descent" (Stargate SG-1)
- "Unnatural Selection" (Stargate SG-1)
- "Reckoning" (Stargate SG-1)
- Andy Mikita in the audio commentary for "New Order"
- Peter DeLuise in the audio commentary for "Reckoning (Part 1)"
- James Tichenor (VisFX supervisor) (2001). Audio Commentary for "Small Victories" (DVD – Stargate SG-1: Season 4). MGM Home Entertainment.
- "Fail Safe" (Stargate SG-1)
- "Ripple Effect" (Stargate SG-1)
- "Camelot" (Stargate SG-1)
- "Flesh and Blood" (Stargate SG-1)