No, have in count that the stars move, so that you can't put too much exposure time. There's an equation to calculate the maximum exposure time you can set not to catch the stars' movement, and it's this one: 500/focal lenght. For example, for a shot taken at 10mm (with the 3/2 factor it makes 15mm), the max. exposure time I could set to catch the stars stood would be: 500/15=33,33 seconds.
To make things brighter I have to increase the ISO value, but, at the same time, I have to take care with the noise this produces. They produce less noise with cold temperatures (the sensor works better when the temperature are cold), that's why it's a bit better to make night pictures in autumn/winter.
I start talking about these things and it's like I cannot stop I just love this!