The move to develop a single rocket capable of different missions is also perplexing for launcher experts. US National Air and Space Museum curator Roger Launius says: "The single rocket idea has never worked very well."And ESA's launcher policy until now has been to create a family of launchers. It is still in the process of preparing to operate from French Guiana from 2011 the Ariane 5 for heavy spacecraft, the Italian-led Vega for small spacecraft and Russia's medium-class Soyuz.Launius speculates that the 1,000kg gap mystery may be traced to unstated defence requirements - Dordain mentioned co-operation with the European Defence Agency at his press conference.Tomorrow's Bird was to have been a two-year study finished by early 2008, but two years on ESA has released only executive summaries. Its implications for Europe's rockets mean, in retrospect, the study should probably have been called Tomorrow's Launcher.
Care to share this evidence?Analyst
I don't know if this counts as evidence but I stopped being a GSO comsat customer recently. Went from satellite to cable for my TV. Cable company gave me a bundled deal for both TV and internet.TV and phone are moving to the internet and the internet is moving to the cloud. GSO comsats can't handle cloud computing due to signal latency issues. So long term they might be in trouble.
Quote from: agman25 on 01/27/2010 04:43 pmI don't know if this counts as evidence but I stopped being a GSO comsat customer recently. Went from satellite to cable for my TV. Cable company gave me a bundled deal for both TV and internet.TV and phone are moving to the internet and the internet is moving to the cloud. GSO comsats can't handle cloud computing due to signal latency issues. So long term they might be in trouble.And that's part of the essense of my question about, What could you do with bigger GEO satellites? Suppose you had a comsat with enough bandwidth to talk directly to the electronics of a cell phone? How big an antenna would that take on the satellite? (The signal latency issue is separate from that.) I will shortly be moving to an area outside T1, cable and DSL reach, and since Hughes.net can't handle Vonage, I'll be back on a landline for phone service. (Actually, I'm probably going to go all-cellular, since there's a big tower on the horizon I can point a yagi aerial at.)
European Space Agency planning its own long-range "ESAS"
With hindsight, wouldn't it have been better for ESA to go from Ariane 4 to a kerolox version, with a three-core variant for heavy payloads? Now that Vulcain exists it may not be a good idea to throw it away and to convert Viking to kerolox. Does this mean Ariane 6 would be inferior to what it might have been had there not been an Ariane 5? Not saying this is the case, just wondering about people's opinions.
Why Kerolox? It translates into less energy per mass-unit of fuel. Agreed, Kerolox is a simpler technology but why would one convert Viking to Kerolox? That would translate into an entirely newly developed engine. Engine development is very expensive. I don't see the advantage of Kerolox over cryogenic.
Quote from: woods170 on 02/13/2010 01:00 pmWhy Kerolox? It translates into less energy per mass-unit of fuel. Agreed, Kerolox is a simpler technology but why would one convert Viking to Kerolox? That would translate into an entirely newly developed engine. Engine development is very expensive. I don't see the advantage of Kerolox over cryogenic.Conventional wisdom has it that kerolox is pretty close to optimal as a first stage propellant. The money spent developing Vulcain might have been better spent developing Vinci.
I was thinking converting Viking from hypergolic to kerolox would be a much smaller change than developing a brand new cryogenic engine. I believe such conversions have happened for US engines.