Clue How To Enter The Blue Meteor

You baisally need to go to the back of the meteor (not the trail) and there is a water source block in there. behid the water there is a button (just span until you pushed it) then you will hear something and to the right the door will open. hopefully it helped you out!

 

Just to add to this cause I had this problem no video tutorial show blue meteor because they all fall off so I had a hard time getting in cause I couldn't get he button no matter how much I spammed so just a tip you should stand on a glass pane to the right of the water touching the meteor and juMp while you spam click cause that's the only way it worked for me and if you have
this pro

 

A little late there, bud.