Photography is all about light and shooting without much light offers a whole host of potential problems. And rewards.
Having minimal light means the shutter needs to be open for a long time, and slow camera shutter speeds result in blurred pictures unless the camera is rock steady throughout. Try holding perfectly still for ten seconds. It can't be done. This means that the camera needs to be put on something that isn't going to move, like a tripod. If you have some sort of vibration reduction on your lens, it should be turned off if the camera is on a tripod.
Even on a tripod, the act of pressing and releasing the shutter button can result in a slight movement of the camera. The way around this is to either use a cable release, or to use the camera's built-in self-timer. Another thing that can reduce blur is to lock the mirror up, if your camera allows this. Check the manual. This keeps the mirror movement from shaking the camera.
Low light would normally call for a wide-open aperture to let more light in (bigger hole = more light), but wide apertures come with narrow depths of field, meaning only a smaller part of the shot may actually be in focus. If you need more of the subject in focus, sacrificing bigger apertures for increased shutter time helps.
Using higher ISOs can also help. This means the sensor is more--well, sensitive. Of course, there's a tradeoff. In film world, high ISO meant increased grain, and in early digital or cheaper digital, it means increased noise. This can be fixed in post-processing to some degree.
The end result of low-light photography can be very rewarding. Although no lens can do what the human eye can do, through long-exposures our cameras are capable of seeing things that we can't.
