▁Point - to - point ▁is ▁a ▁category ▁of ▁sub - orb ital ▁space fl ight ▁in ▁which ▁a ▁space craft ▁provides ▁rapid ▁transport ▁between ▁two ▁terrest rial ▁locations . ▁A ▁conventional ▁air line ▁route ▁between ▁London ▁and ▁Sydney , ▁a ▁flight ▁that ▁normally ▁last s ▁over ▁twenty ▁hours . ▁With ▁point - to - point ▁sub orb ital ▁travel ▁the ▁same ▁route ▁could ▁be ▁travers ed ▁in ▁less ▁than ▁one ▁hour . ▁While ▁no ▁company ▁offers ▁this ▁type ▁of ▁transport ation ▁today , ▁Space X ▁has ▁revealed ▁plans ▁to ▁do ▁so ▁as ▁early ▁as ▁the ▁ 2 0 2 0 s ▁using ▁Star ship . ▁Sub orb ital ▁space fl ight ▁over ▁an ▁inter cont inental ▁distance ▁requires ▁a ▁vehicle ▁velocity ▁that ▁is ▁only ▁a ▁little ▁lower ▁than ▁the ▁velocity ▁required ▁to ▁reach ▁low ▁Earth ▁orbit . ▁If ▁rock ets ▁are ▁used , ▁the ▁size ▁of ▁the ▁ro cket ▁relative ▁to ▁the ▁payload ▁is ▁similar ▁to ▁an ▁Inter cont inental ▁Ball istic ▁Miss ile ▁( IC B M ). ▁Any ▁inter cont inental ▁space fl ight ▁has ▁to ▁sur mount ▁problems ▁of ▁he ating ▁during ▁atmosphere ▁re - entry ▁that ▁are ▁nearly ▁as ▁large ▁as ▁those ▁faced ▁by ▁orb ital ▁space fl ight . ▁ ▁Or b ital ▁▁ ▁A ▁minimal ▁orb ital ▁space fl ight ▁requires ▁much ▁higher ▁veloc ities ▁than ▁a ▁minimal ▁sub - orb ital ▁flight , ▁and ▁so ▁it ▁is ▁techn olog ically ▁much ▁more ▁challeng ing ▁to ▁achieve . ▁To ▁achieve ▁orb ital ▁space fl ight ,