Starmate 5 and antenna...

[BJYourk]

Just got a Starmate 5 for my parents(also has car adapter and came with FM modulator). They have an 08 Escape with an IPOD adapter built in the console. Can you just plug that receiver into the AUX jack on the car and not use any antenna for the Starmate? In other words, will the Starmate then use the cars antenna for reception?

Thanks!....oh and hello

 

[BJYourk]

Forgot to add that the car came satellite ready(they had Sirius for first 6 months free).
*Just read that the factory installed module is under the passenger seat. Now, if I need an antenna with the Aux input, can I just go into the module under the seat rather than taking the radio out?