Stellar drift, manual dialing and the 300 light years range.

[gineer]

I have a question about manual dialing.

In "Children of the Gods" it is stated that SGC tried dialing various random addresses after the original Abydos mission in the Movie, and none worked.

In "2001", Carter says that without a DHD, or a dialing computer, a stargate is only able to connect to stargates in a range of 300 light years. That's why the Aschen, who also lacked a DHD couldn't dial any other planet expect Volia. There are only two planets is this range from Earth: Abydos and Heliopolis.

Does this mean, that if the stargate dials a planet that is further away than 300 light years, additional coordinates, or machine-code instructions are needed to be sent to the stargate either from a DHD or a computer, not just the 7-symbol address?

If they didn't find the Cartouche room on Abydos and just saw the Jaffa dialing Chulak from the pyramid, then tried dialing Chulak from Earth, would it have not connected?

In some other episodes with manual dialing (Prisoners, New Ground, Nemesis, Bad Guys) this "300 light year range" problem seems to be ignored, yet in "2001" it is precisely this limitation of manual dialing, with which they can find the location of the Aschen Homeworld.

[escyos]

I always figured that the Stargate itself stored location data rather than the dial home device (or maybe they both do) so no matter which Stargate is dialed, information is passed along. Example: Hadante was dialed by the Stargate on P3X-775 so it passed along the information that it had received from the rest of the network.

Stargates that were buried for a long time (Earth, P4C-970) had no additional navigation data so as with Stargates further out, the coordinates were incorrect. Chulak is 2,000 light years from Earth so maybe they would have been able to reconfigure it to work if no cartouche had been found, but probably not for larger distances.

Or, you know, they disregarded it all.

[jfarrell327]

That is what it seems like, early on they had a certain amount of rules and procedures and later they changed it... Early on we had the computer and were just figuring things out, then the original cartouche on Abydos enabled them to make the calculations for stellar drift. In the movie Abydos was in a whole different galaxy but in the first episode it was only like 300 light years away or so, either way it was the closest planet within the gate network.

Does this mean, that if the stargate dials a planet that is further away than 300 light years, additional coordinates, or machine-code instructions are needed to be sent to the stargate either from a DHD or a computer, not just the 7-symbol address?

Negative. 7 symbols are used for any gate in our galaxy that we were able to calculate, if we had a DHD, then we wouldn't need to but since we only had our computer we needed the stellar drift calculations for planets further away than 300 light years or so...

If they didn't find the Cartouche room on Abydos and just saw the Jaffa dialing Chulak from the pyramid, then tried dialing Chulak from Earth, would it have not connected?

Nope it wouldn't connect because the address would be different from Abydos compared to Earth, the point of origin that is. Not to mention they had a DHD we didn't...

In some other episodes with manual dialing (Prisoners, New Ground, Nemesis, Bad Guys) this "300 light year range" problem seems to be ignored, yet in "2001" it is precisely this limitation of manual dialing, with which they can find the location of the Aschen Homeworld.

In those episodes they had an alternate power source, except in New Ground they did have a DHD... the 300 light year range was mainly used just in the beginning until we gained more knowledge and had more addresses and the stellar drift calculations from Colonel O'Neill from the ancient memory downloaded into his brain. After we had all of those addresses and the calculations needed the 300 light year range problem was eliminated.

[Xaeden]

Here's the exact quote:

CARTER
In my early work with the Stargate program, I theorized that all things being equal, the outside limit per lock between two planets without a DHD is three hundred light years. The computer is searching for viable coordinates within that radius of the Volian system, P3A-194.

Note that she says two planets without a DHD. Meaning, if one Stargate (whether it be the one being dialed to or the one dialing out) has a DHD then that limitation would not apply.

Note also that the reason they couldn't dial other gates was simply because they did not know any other addresses and that no mention was made of needing Earth to supply them with a DHD as part of their agreement. The plan was simply to provide them with a list and let them go exploring.

[thekillman]

Here's the exact quote:



Note that she says two planets without a DHD. Meaning, if one Stargate (whether it be the one being dialed to or the one dialing out) has a DHD then that limitation would not apply.

Note also that the reason they couldn't dial other gates was simply because they did not know any other addresses and that no mention was made of needing Earth to supply them with a DHD as part of their agreement. The plan was simply to provide them with a list and let them go exploring.

300 light years is because of stellar drift. The resolution of gate addresses is such that it allows for some movement of the target stargate (dialing a planet would be hell otherwise). beyond 300 lightyears, the stellar drift is such that the target gate is outside the target (dialing) area and thus can not be found. If the dialing gate has either a DHD or an address corrected for stellar drift, there is no limit to how far you can dial.

Lastly, random dialling leads to nothing. Judging by the amount of episodes, roughly one planet per episode, one team per episode, we can judge that there are maybe some 10 000 stargates in the milky way (200 planets over the entire series, 5 and eventually 25 SG teams leading to ~10 teams * 200 planets per team over the series = 2000, despite their best efforts not all stargates have been dialled, and a number has been buried. 10 000 seems to be a fair estimate given that Sg1 continued exploring into SGA and SGU and still had no indication of all being known).

A stargate adress has 7 symbols, with unique symbols and 39 total it's 39!-32! possibilities if my mathematical memory serves (39*39*37*36*35*34*33) which ended somewhere in 10 billion possibilities. AKA the chance of random dialing working is astronomically slim when you don't account for stellar drift, and slightly less astronomically slim when you do.

[Xaeden]

300 light years is because of stellar drift. The resolution of gate addresses is such that it allows for some movement of the target stargate (dialing a planet would be hell otherwise). beyond 300 lightyears, the stellar drift is such that the target gate is outside the target (dialing) area and thus can not be found. If the dialing gate has either a DHD or an address corrected for stellar drift, there is no limit to how far you can dial.

No, stellar drift is a separate problem for which no specific max distance can be universally applied. Whether calculations need to be made to account for stellar drift is based on both the distance of the Stargate that the non-DHD Stargate wants to dial to and the amount of time that has passed since the last update. As more time passes, that distance becomes shorter. So the range of gates that Earth was able to dial after finding a Stargate that had been cut off from its DHD for thousands of years would be shorter than the range of gates that the Aschen would have been able to dial after finding a Stargate that was probably only cut off from its DHD hundreds of years ago.

Look at the quote again. Carter was talking about a uniform max distance that applied to two planets (not one) without a DHD.

Lastly, random dialling leads to nothing.

Hence the part of my post where I said that the reason the Aschen couldn't dial other gates was because they didn't have any addresses - If you don't have any valid addresses you're obviously unlikely to randomly guess any of them. Although, as improbable as it may be, it amazing happened before with the Unas slaver.

[TwelveEleven]

300 light years is because of stellar drift. The resolution of gate addresses is such that it allows for some movement of the target stargate (dialing a planet would be hell otherwise). beyond 300 lightyears, the stellar drift is such that the target gate is outside the target (dialing) area and thus can not be found. If the dialing gate has either a DHD or an address corrected for stellar drift, there is no limit to how far you can dial.

Lastly, random dialling leads to nothing. Judging by the amount of episodes, roughly one planet per episode, one team per episode, we can judge that there are maybe some 10 000 stargates in the milky way (200 planets over the entire series, 5 and eventually 25 SG teams leading to ~10 teams * 200 planets per team over the series = 2000, despite their best efforts not all stargates have been dialled, and a number has been buried. 10 000 seems to be a fair estimate given that Sg1 continued exploring into SGA and SGU and still had no indication of all being known).

A stargate adress has 7 symbols, with unique symbols and 39 total it's 39!-32! possibilities if my mathematical memory serves (39*39*37*36*35*34*33) which ended somewhere in 10 billion possibilities. AKA the chance of random dialing working is astronomically slim when you don't account for stellar drift, and slightly less astronomically slim when you do.

It's (38! * 37! * 36! * 35! * 34! * 33!) / 720 (One in 720 addresses of the same symbol combinations can be an active Stargate and you don't need the 7th symbol because that's your home symbol.) Obviously excluding the 8 symbol addresses. It's not clear how many of those there are. Really depends on how many galaxies are populated with Stargates.