WHICH rocket?
Quote from: Hauerg on 10/09/2018 03:10 pmWHICH rocket?A Big one.Neglecting the other issues, and altitude, because it can be easily neglected, HST is at 28.5 degrees, ISS 51.6.To change inclination by 28 degrees in LEO needs around 3.7km/s.If your rocket weighs a couple of tons, you end up (if hypergolic) needing around 40 tons, or with methalox, 25 tons of propellant. (neglecting initial rendevous propellant)If you use something based off a commercial comsat, with electric propulsion, likely you end up with around 18 tons or so total launch mass.A side-benefit from this is you've probably come pretty close to developing something to push modules electrically to LOP-G.
I remember that there were two NRO 'Hubble class' telescopes that were 'gifted' to NASA. I've just Googled about them but only get articles with vague sets of details about them. Are one or both of these going to be recycled into space telescopes? Could one of them be a better platform for the WFIRST concept?
No need for a Dragon or crew. Just a spacecraft bus with rendezvous and docking capability and a separate non propulsive attitude control system. The propulsion system used for rendezvous and docking then can be used for reboost.
Quote from: Jim on 10/09/2018 05:54 pmNo need for a Dragon or crew. Just a spacecraft bus with rendezvous and docking capability and a separate non propulsive attitude control system. The propulsion system used for rendezvous and docking then can be used for reboost.Very elegant idea.
Dragon cannot support an EVA. It would require an external airlock module.
Quote from: Lars-J on 10/09/2018 06:21 amDragon cannot support an EVA. It would require an external airlock module.Ah, but we'd just need to take a page out of the Soviet playbook and add an inflatable airlock. I'm sure Bigelow can come up with something...
Quote from: Oersted on 10/10/2018 09:16 amQuote from: Lars-J on 10/09/2018 06:21 amDragon cannot support an EVA. It would require an external airlock module.Ah, but we'd just need to take a page out of the Soviet playbook and add an inflatable airlock. I'm sure Bigelow can come up with something...And some way to get it from the trunk to Dragons docking port.
Quote from: nacnud on 10/10/2018 11:03 amQuote from: Oersted on 10/10/2018 09:16 amQuote from: Lars-J on 10/09/2018 06:21 amDragon cannot support an EVA. It would require an external airlock module.Ah, but we'd just need to take a page out of the Soviet playbook and add an inflatable airlock. I'm sure Bigelow can come up with something...And some way to get it from the trunk to Dragons docking port.*** dons fire-proof suit ***While we're about it, why not just slap a Raptor US on F9 to increase performance? :p
Quote from: octavo on 10/10/2018 12:27 pmQuote from: nacnud on 10/10/2018 11:03 amQuote from: Oersted on 10/10/2018 09:16 amQuote from: Lars-J on 10/09/2018 06:21 amDragon cannot support an EVA. It would require an external airlock module.Ah, but we'd just need to take a page out of the Soviet playbook and add an inflatable airlock. I'm sure Bigelow can come up with something...And some way to get it from the trunk to Dragons docking port.*** dons fire-proof suit ***While we're about it, why not just slap a Raptor US on F9 to increase performance? :p Now where did I leave my flame-thrower? Let's just not go down the "Raptor upper stage"-path again. Or we will invoke the wrath of Lar.
Ok, what's so special about hubble that we can't simply build a replacement? Not with all new and super fancy stuff like the want with WFIRST, but with the technology level Hubble has now? Hubble has been launched 30 years ago, upgraded the last time almost 10 years ago.Why isn't it possible to build something based on a commercial spacecraft bus, for let's say 500 mio. $ that's new and shiny and has the same capabilities of 30-10 year old hardware?
Quote from: Jim on 10/09/2018 05:54 pmNo need for a Dragon or crew. Just a spacecraft bus with rendezvous and docking capability and a separate non propulsive attitude control system. The propulsion system used for rendezvous and docking then can be used for reboost.You left out a tiny little detail: the need to disable Hubble's own attitude control system to allow the ACS of the docked spacecraft bus to take over. Which means completely changing the way the Hubble computers operate the telescope.