... Astronomy for Kids . ... Astronomy 101 . ... Primordial dry ice fuels comet jets . Images from the November 4 Comet 103P/Hartley flyby show spectacular jets of gas and particles bursting from many distinct spots on the surface of the comet. ... One of the biggest comet findings coming out of the amazing images and data taken by the University of Maryland-led EPOXI mission as it zipped past Comet 103P/Hartley last week is that dry ice is the т??jetт?? fuel for this comet and perhaps many others. ...