Quote from: Lars_J on 06/15/2012 05:27 pmQuote from: Ben the Space Brit on 06/15/2012 04:04 pmThis way, the platform is in place at the turn of the decade and SLS can be focussed on what it does that makes it unique (no current or actively in-development commercial vehicle can do this) - launch Orion or mission cargo to EML-1 with a single launch. Not to nitpick, but there is actually another LV in development which would be able to launch a tweaked version of a flying cargo craft to EML-1 with a single launch.Actually, there are several. A Proton may be able to push a modified Progress to EML1. Atlas V (i.e. 551) and maybe the Delta IV Medium+ should be able to push a Cygnus to EML1. And I'm sure we can think of a few others. Orion is big and heavy compared to most spacecraft, even most manned spacecraft (not that that's /necessarily/ a bad thing).
Quote from: Ben the Space Brit on 06/15/2012 04:04 pmThis way, the platform is in place at the turn of the decade and SLS can be focussed on what it does that makes it unique (no current or actively in-development commercial vehicle can do this) - launch Orion or mission cargo to EML-1 with a single launch. Not to nitpick, but there is actually another LV in development which would be able to launch a tweaked version of a flying cargo craft to EML-1 with a single launch.
This way, the platform is in place at the turn of the decade and SLS can be focussed on what it does that makes it unique (no current or actively in-development commercial vehicle can do this) - launch Orion or mission cargo to EML-1 with a single launch.
Quote from: Robotbeat on 06/15/2012 05:48 pmQuote from: Lars_J on 06/15/2012 05:27 pmQuote from: Ben the Space Brit on 06/15/2012 04:04 pmThis way, the platform is in place at the turn of the decade and SLS can be focussed on what it does that makes it unique (no current or actively in-development commercial vehicle can do this) - launch Orion or mission cargo to EML-1 with a single launch. Not to nitpick, but there is actually another LV in development which would be able to launch a tweaked version of a flying cargo craft to EML-1 with a single launch.Actually, there are several. A Proton may be able to push a modified Progress to EML1. Atlas V (i.e. 551) and maybe the Delta IV Medium+ should be able to push a Cygnus to EML1. And I'm sure we can think of a few others. Orion is big and heavy compared to most spacecraft, even most manned spacecraft (not that that's /necessarily/ a bad thing).Would this hypothetical cargo mission be crashed into the lunar surface after payload delivery?
Several documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due – it is claimed – to the uncertainty with NASA’s long term budget projections.
Slightly tangentially, but to ask about QuoteSeveral documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due it is claimed to the uncertainty with NASAs long term budget projections.Is any resolution of that situation in sight? And if not, what then? NASA could continue on a steady-as-she-goes course without a roadmap for several years yet, but what about the 180-day report the Appropriations committees asked for?
Several documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due it is claimed to the uncertainty with NASAs long term budget projections.
2) EML2 is on the far side of the moon. If people are at the new Waystation, it would be nice to be able to communicate with them. How will they send and receive signals to earth?3) The waystation would be solar powered. However, the moon has 14.77 days of sunlight followed by 14.77 days of "night". Would a solar array be needed to capture twice the normal load together with batteries to hold 2 weeks of power?
Quote from: ChileVerde on 06/15/2012 06:06 pmSlightly tangentially, but to ask about QuoteSeveral documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due – it is claimed – to the uncertainty with NASA’s long term budget projections.Is any resolution of that situation in sight? And if not, what then? NASA could continue on a steady-as-she-goes course without a roadmap for several years yet, but what about the 180-day report the Appropriations committees asked for?You will never see any plan from this administration, regardless if it lasts less than another year or another five. To answer the "what then" question. Expect studies and Design Reference Missions. Expect unfocused technology development programs in order for the centers to have something to do. Expect SLS to continue to drag along, with only artifical support from the administration. Expect Orion to follow suit since they have been coupled on purpose for this reason. Expect ISS to be the center and only operational program for the next 20 years and expect the blame for this to continued to be placed on the Bush administration for cancelling Shuttle and trying CxP. Expect their answer to be "we're going to an asteroid" but having kicked that so far down the road intentionally they never have to do anything about it.
Slightly tangentially, but to ask about QuoteSeveral documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due – it is claimed – to the uncertainty with NASA’s long term budget projections.Is any resolution of that situation in sight? And if not, what then? NASA could continue on a steady-as-she-goes course without a roadmap for several years yet, but what about the 180-day report the Appropriations committees asked for?
Quote from: Go4TLI on 06/15/2012 06:09 pmQuote from: ChileVerde on 06/15/2012 06:06 pmSlightly tangentially, but to ask about QuoteSeveral documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due – it is claimed – to the uncertainty with NASA’s long term budget projections.Is any resolution of that situation in sight? And if not, what then? NASA could continue on a steady-as-she-goes course without a roadmap for several years yet, but what about the 180-day report the Appropriations committees asked for?You will never see any plan from this administration, regardless if it lasts less than another year or another five. To answer the "what then" question. Expect studies and Design Reference Missions. Expect unfocused technology development programs in order for the centers to have something to do. Expect SLS to continue to drag along, with only artifical support from the administration. Expect Orion to follow suit since they have been coupled on purpose for this reason. Expect ISS to be the center and only operational program for the next 20 years and expect the blame for this to continued to be placed on the Bush administration for cancelling Shuttle and trying CxP. Expect their answer to be "we're going to an asteroid" but having kicked that so far down the road intentionally they never have to do anything about it. Better than firing everyone because they proposed a base on the Moon! The alternative to the current administration is no better in this regard.
Quote from: Robotbeat on 06/15/2012 06:40 pmQuote from: Go4TLI on 06/15/2012 06:09 pmQuote from: ChileVerde on 06/15/2012 06:06 pmSlightly tangentially, but to ask about QuoteSeveral documented dates for the completion of an exploration roadmap have come and gone over the last several months, mainly due – it is claimed – to the uncertainty with NASA’s long term budget projections.Is any resolution of that situation in sight? And if not, what then? NASA could continue on a steady-as-she-goes course without a roadmap for several years yet, but what about the 180-day report the Appropriations committees asked for?You will never see any plan from this administration, regardless if it lasts less than another year or another five. To answer the "what then" question. Expect studies and Design Reference Missions. Expect unfocused technology development programs in order for the centers to have something to do. Expect SLS to continue to drag along, with only artifical support from the administration. Expect Orion to follow suit since they have been coupled on purpose for this reason. Expect ISS to be the center and only operational program for the next 20 years and expect the blame for this to continued to be placed on the Bush administration for cancelling Shuttle and trying CxP. Expect their answer to be "we're going to an asteroid" but having kicked that so far down the road intentionally they never have to do anything about it. Better than firing everyone because they proposed a base on the Moon! The alternative to the current administration is no better in this regard.Is this the space policy section? Besides that soundbite is getting a little stale isn't it? There is plenty to talk about here without getting into a partisan debate.
Quote from: A_M_Swallow on 06/15/2012 04:34 amThe 2010 NASA Authorisation Act probably is not a problem since a new one is due within a couple of years. This is a good time to start lobbying to add a EML-2 space station.Its also a good time to start praying that we even get to keep a program at all.Things are never as good as they seem when they appear to be going well. Things are also never as bad as they seem when they appear to be going badly.I find this truism applies about 98% of the time and has saved me much gnashing of teeth.The budget cuts that are coming........you have no idea......Think about your worst case scenario, even based on what we already know.Now make it 5 times worse. One of two thing is going to happen in the next 8 years:1. Budgets are slashed for federal systems/programs across the board. Or.2. Spending continues until repeat defaults occur and/or currency collapses (really really bad day.) Oh and don't forget about the inflation problem either.I will be happy if even EM-1 flys, while it would be good to try and lobby for the EML missions, I just don't know if it would yield anything or even hurt the argument for this program overall because "you want more money for space? What about the entitlement programs ect" Really almost praying for NASA's budget in the future, especially what the post November outcome will be. Because right now I don't see a future.
The 2010 NASA Authorisation Act probably is not a problem since a new one is due within a couple of years. This is a good time to start lobbying to add a EML-2 space station.
I suppose if you wanted to. Earth escape would probably be the usual disposal option, since you're pretty close to Earth escape at EML1/2.Cygnus weighs only 1500kg dry (expanded version is 1800kg dry), so with a small amount of payload (a ton or so), even Falcon 9 (v1.1, i.e. every launch after CRS-2) should have no problem sending it on a ballistic trajectory to EML1. Atlas V 551 would be way overpowered for sending Cygnus to EML1. Though perhaps it'd be appropriate for mission elements and add-ons. An Atlas V vanilla (i.e. 401) should also be enough to send Cygnus to EML1.EDIT: Even Delta IV, all flavors, should be enough to put Cygnus to EML1.
Quote from: Robotbeat on 06/15/2012 06:01 pmI suppose if you wanted to. Earth escape would probably be the usual disposal option, since you're pretty close to Earth escape at EML1/2.Cygnus weighs only 1500kg dry (expanded version is 1800kg dry), so with a small amount of payload (a ton or so), even Falcon 9 (v1.1, i.e. every launch after CRS-2) should have no problem sending it on a ballistic trajectory to EML1. Atlas V 551 would be way overpowered for sending Cygnus to EML1. Though perhaps it'd be appropriate for mission elements and add-ons. An Atlas V vanilla (i.e. 401) should also be enough to send Cygnus to EML1.EDIT: Even Delta IV, all flavors, should be enough to put Cygnus to EML1.According to the NLS-II site, the C3=0 payloads of the launchers are:Falcon 9 Block 2: 2,500kgFalcon 9 v1.1 (my guess): 3,200kgAtlas V 401: 3,000kgAtlas V 411: 3,900kgAtlas V 421: 4,700kgAtlas V 431: 5,100kgAtlas V 551: 6,000kgThe only issue is price performance, if we follow the NWO price, the basic Atlas was around 140M, but each solid was an extra 10M. If you assume a 2000kg Cygnus (due to fuel and such), and assuming the Cygnus itself costs 50M. For 190M (Atlas V 401+Cygnus) you'd get 1,000kg of cargo (190,000USD/kg). But for 220M (Altas V 431+Cygnus) you'd get 3,100kg (71,000USD/kg). In fact, assuming 80M for the Falcon 9 v1.1 (and it's performance is a guess) you'd get 130M for 1,200kg (or 108,000USD/kg). So the Atlas V 431 would be the cheapest alternative. An Atlas V 551 would be (60,000USD/kg), even cheaper!
Atlas V 551: 6,000kg
It's great to see this concept (of using ISS to build a small EML halo station) is continuing to get attention. To be fair it needs to be compared with an approach that builds the halo station "de novo" at its intended orbit. Delivering components directly there is essentially equivalent to delivering them to C3=0, and: Quote from: baldusi on 06/15/2012 07:29 pmAtlas V 551: 6,000kgSo the question becomes, "How is using ISS better than building an EML station out of 6t chunks?"
if we build at ISS, we can get started right away, before we have a way to get a crewed vehicle to EML1.
Quote from: Robotbeat on 06/15/2012 08:20 pmif we build at ISS, we can get started right away, before we have a way to get a crewed vehicle to EML1.I suspect you may have hit the nail on the head. NASA wants to use crews to construct space stations, not just send crews to visit them. Methinks that's a mighty expensive thing to want!
So the question becomes, "How is using ISS better than building an EML station out of 6t chunks?"(EDIT to add: "Or 9t chunks?" with image showing C3=0 payloads.)
Also, it's not unjustified to want to use ISS-heritage components, which have a much higher TRL than a new system would be and can be built much faster. They have to be built like ISS was, to a certain extent. That actually may end up being the cheapest and fastest option. Heck, in some cases, they have large components already built. It also means they can make use of the ISS spare pool.