Purely from a military perspective, everything I have read suggests that Israel can not accomplish this task on their own. There are too many targets and they are too well defended and Israel lacks the refueling capacity and ordinance to be effective. If Iran is actually working on a nuclear weapon, then at best, Israel, by themselves, only set it back by a little. Of course, such an attack, may also just spur Iran to develop the program even quicker.
Their only real hope is to attack on their own knowing that America will have to get involved. But, I'm not sure American involvement will include actually going after the targets in question. Perhaps all they would do is act defensively. So, they still wouldn't accomplish their intended goal.
Meanwhile they have a lot to lose. It probably further erodes their standing in the world and it certainly erodes their standing in the Middle East. Iranian air defences are probably good enough where the loss of Israeli planes and pilots is a real possibility. They open themselves up to rocket attacks from Iran. Worse than that is they open themselves up to rocket attacks from Hezbollah. And of course there is always the possibility of opening up the conflict in more global ways. Iran closing the Straight of Hormuz, for example. Worst case scenario is that Russia says enough is enough and gets involved. Honestly, I just don't see Russia sitting on their hands if American planes fly into Iran.