re hst servicing mission scheduled for days in article rd g ckb access digex net prb access digex com pat writes how will said re boost be done grapple hst stow it in cargo bay do oms burn to high altitude unstow hst repair gyros costar install fix solar arrays then return to earth actually the reboost will probably be done last so that there is a fuel reserve during the evas in case they have to chase down an adrift astronaut or something like that but yes you ve got the idea the reboost is done by taking the whole shuttle up my guess is why bother with usingthe shuttle to reboost why not grapple do all said fixes bolt a small liquid fueled thruster module to hst then let it make the re boost somebody has to build that thruster module it s not an off the shelf item nor is it a trivial piece of hardware since it has to include attitude control hst s own is not strong enough to compensate for things like thruster imbalance guidance there is no provision to feed gyro data from hst s own gyros to an external device and separation you don t want it left attached afterward if only to avoid possible contamination after the telescope lid is opened again you also get to worry about whether the lid is going to open after the reboost is done and hst is inaccessible to the shuttle the lid stays closed for the duration of all of this to prevent mirror contamination from thrusters and the like the original plan was to use the orbital maneuvering vehicle to do the reboost the omv was planned to be a sort of small space tug well suited to precisely this sort of job unfortunately it was costing a lot to develop and the list of definitely known applications was relatively short so it got cancelled svr resembles a high speed collision henry spencer u of toronto zoology between svr and sunos dick dunn henry zoo toronto edu utzoo henry
