Fill in the Blanks Main SequenceOnline version fill in the blanks for the steps by Kristine Vester 1 together protons electrons star combo repeats attaches Smaller neutron helium 2 hydrogen pressure nucleus fusion collide Hotter sequence dense particle Nuclear red supergiant subatomic Main stars are what most stars are . They fuse hydrogen in their core . / cooler ones will take the giant branch . / bigger ones will take the branch . Fusion is what happens in the core to produce the star's energy / light . Without , an object can not be a . Most fusion is fusing to helium . The steps are as followed : The core is so hot and that the causes to be flying around on their own without . Two protons hit each other and stick . One proton turns into a . A flies off . Another proton comes in and to the proton / neutron Those last two steps with another group Those two groups and stick together . We lose two of the protons leaving protons and 2 neutrons . This is a complete .