You Cannot, There simply is no way unles your game glitches or goes screwy or something like that, so if your desperate for a deoxys eithe but a plane ticket 2 Japan or learn 2 us a game shark. You could try 2 glitch your game but that is far from a good idea.
There is a way to get it and i am 110% that you can without cheats.
I have been asked to go to the moon before and i clicked no and went to the Pokemon centre and came back, i couldn't get back on. I turned the game on and off and it still didnt work. So i started a new game.
I now know how exactly to get on the rocket launch.
The rocket launch goes up once a week after you beat the elite 4. For me it goes up 1 launch every Tuesday but it may be a different day for everybody else. You need a total of 50+ or 100+ rocket launches to go to the moon. So the point is, a launch a week means you will have to wait a total of 50 weeks (50 launches) in order to get jirachi/deoxys. If you are asked, click yes otherwise you will have to start a new game and wait another 50 weeks. (p.s my rocket launch is currently on 43, another 7 weeks and im goin to catch jirachi, yay!)
You can't.
You wanna know the answer? No. Same possibility as you catching a deoxys with a newborn pichu without a gameshark.
You don't get Deoxys from anyone in the mining museum You have to trade it from Diamond/Pearl, or migrate it from Ruby/sapphire/emerald if you went to any of the events.
Because leafgreen and firered are remakes of generation one games, you can't get a deoxys in either except through trades, action replays, or Nintendo events
You get it via special events on wifi.
No.
No you can't catch deoxys by using cheats
Unfortunately the event has already been over :C
you only can get them with cheats (i realy hate that with all that events and cheats =[ )
There is no deoxys fossil. To obtain Deoxys in any of the games you have to get it through an event or through cheats.
cheats
Actually, you can't get Deoxys w/o cheats. You have to go to a Nintendo event. So even if you try to talk to the guy in the space center(which others say)you can't go to the moon. It's impossible to get Deoxys without cheats.
You can trade for them. That's all I can say.
impossible without cheating
To get Deoxys, you have to migrate from leaf green ruby fire red saphire emerald versions, just to get Deoxys
you need a ticket then go to birth island
You can't.