You keep playing Sims 2 but never have you managed to get abducted by aliens.The chances of abduction are rather low and you have to be persistant. The abduction in Strangetown is set up, of course, and you got lucky in Veronaville.Here are some instructions in order to make the abduction more possible.
Step 1

Encourage your Sims 2 to stargaze. Not look through, this wouldn't have any plain result rather than improving their logic skills.Basically, the longer they star-gaze, the higher the chance of them being abducted. So start your sim star-gazing as soon as it gets dark. There is no optimum time during the night. People come up with times (between midnight and 4am, usually) but there's nothing in the coding for that.
Step 2
To maximize the chance of abduction you have to have them star-gaze all night without stopping. What happens is, the first hour, there is a really small chance of them being abducted, the second hour, the chance gets higher, the third hour, higher again and so on. However, if they stop for ANY reason and then start again, the chance of abduction goes back to the first hour.
Step 3

Be patient.Aliens will abduct your Sims at night or early morning (any time that it is dark outside). ANY teen or older Sim can be abducted by aliens, but only adult males will come back pregnant.
Step 4
If you still don't have any results then try the cheat method. Take the shortcut: CTRL+SHIFT+C and type '"BoolProp testingcheatsenabled true" without the " " . Select your sim, right-click on a telescope while the abducted-to-be sim is in control, and select FORCE ABDUCTION or whatever it says. Your sim will look through the telescope and get abducted. "BoolProp testingcheatsenabled false" turns the cheat off.
Tips
If you want to do it without cheating, you need to have them in the green as far as possible before they start star-gazing. - Abducting is a rare occurrence. Maybe once a week after staring at the stars all night every night. If you do a web search, you can probably find a walkthrough online that would tell you all the tricks to the game.
Warnings
- Having your Sims star-gazing all night is difficult since they develop the need to bladder, eat and sleep . Also, although the chances of abduction do increase they never get high. However, this method does work if you are persistent.
You should know that in case your Sim gets abducted, most probably he/she will end up pregnant. That means he/she will bear alien babies. You can also use a cheat to have all your need green, "maxmotives" then "motivedecay off"