someone said hulk has unlimited strength. he just has unlimited potential, which means although so far there hasnt been shown a limit to it, it doesnt go up to infinate straight away. it climbs as he gets angry. he has limits, until he gets angry enough to go beyond them. then he has further limits that he needs to go beyond by becoming more angry.
besides that, galactus is basically a star. when he was killed but not quite he became a star. a simple solar flair give off the same power as 40 billion Hiroshima-size atomic bombs. i doubt that the hulk has come anywhere near close to this kind of power. wether or not he is capable of it is another matter. so galactus does have this power, and does not need to be angry to use it. that much force could at the very least remove the helmet of the juggernaut.
galactus has professor x and above telepathic abilities. where as he wouldnt hesitate to use them at full force to kill the juggernaut. even hand to hand i think galactus could take it. that much force would do some serious damage to the juggernaut. im a big juggernaut fan, but being over class 100 strength isnt that big a deal next to galactus. he could be at class 400 and i doubt it would matter.
and if juggernaut is vunerable to attacks on the molecular level isnt one of the attributes of the power cosmic rearanging things on a molecular level? no matter how much i or anyone else loves the juggernaut, he isnt going to win this. and he isnt going to survive to have it called a draw.