Quote from: kevin-rf on 12/07/2012 10:00 amQuote from: FOXP2 on 12/06/2012 11:18 pm...Viking lander only weighed 0.6 tons plus 0.5 tons for heat shield.. How much did the Viking cruise stage, eer orbiter weigh again? That is why it flew on a Titan! If you had separated the two, it could have flown on smaller rockets, maybe.Out of interest would the Falcon 9 be capable of launching this rover along with its EDL and cruise stage?
Quote from: FOXP2 on 12/06/2012 11:18 pm...Viking lander only weighed 0.6 tons plus 0.5 tons for heat shield.. How much did the Viking cruise stage, eer orbiter weigh again? That is why it flew on a Titan! If you had separated the two, it could have flown on smaller rockets, maybe.
...Viking lander only weighed 0.6 tons plus 0.5 tons for heat shield..
Quote from: kevin-rf on 12/07/2012 05:33 pmQuote from: Star One on 12/07/2012 05:28 pmThat's a good point and by then the FH should have clocked up enough flights to prove its reliability for such a mission.For the just announced next rover, Falcon (9 or Heavy) needs to be Nuclear certified. I would guess that's an involved process?
Quote from: Star One on 12/07/2012 05:28 pmThat's a good point and by then the FH should have clocked up enough flights to prove its reliability for such a mission.For the just announced next rover, Falcon (9 or Heavy) needs to be Nuclear certified.
That's a good point and by then the FH should have clocked up enough flights to prove its reliability for such a mission.
The planetary science community is being eaten alive by launch vehicle costs, and they long for the return of the Delta II or something in that cost range. So they (NASA and the scientists) would definitely want to switch, even if that required sinking money into nuclear certifying a new vehicle.
Is this true though? Launch costs are 5-10% of a planetary mission and well understood. It is the spacecraft that are expensive and most likely to suffer unreasonable cost growth.
There are several recent missions, including Juno and New Horizons, that got slammed by those increases--not only Delta II going up in cost, but being forced to shift from a Delta II to the more expensive Atlas V because DII was being phased out.
Quote from: Blackstar on 12/08/2012 01:46 pmThere are several recent missions, including Juno and New Horizons, that got slammed by those increases--not only Delta II going up in cost, but being forced to shift from a Delta II to the more expensive Atlas V because DII was being phased out.I find it hard to believe that either one of those two missions could have launched on Delta II in the first place, given their mass and C3 requirements. What am I missing here?
Quote from: ugordan on 12/08/2012 01:53 pmQuote from: Blackstar on 12/08/2012 01:46 pmThere are several recent missions, including Juno and New Horizons, that got slammed by those increases--not only Delta II going up in cost, but being forced to shift from a Delta II to the more expensive Atlas V because DII was being phased out.I find it hard to believe that either one of those two missions could have launched on Delta II in the first place, given their mass and C3 requirements. What am I missing here?I was referring to other missions that have had to move from Delta II to Atlas V.Cost increases happened to Delta II, they happened to Atlas V, and the retirement of the Delta II forced a transition to the more expensive Atlas V.
Interesting, I didn't know that. Any likelihood of using Falcon 9 or is it far too early for them to trust it at this point?
Grunsfeld asked in his talk for voluntiers for the science definition team for the new rover and a few hands were raised. (more of joke) In this process a more astrobiology rover or a more geology rover or a more geophysics rover might be the outcome strongly depending on the group selected to do the science definition.
Even if they can use MSL spare parts it will be challenging to stay below 1.5 G$. For me this sounds like: Do not change anything which means significant cost increase.
Quote from: stone on 12/08/2012 06:26 pmGrunsfeld asked in his talk for voluntiers for the science definition team for the new rover and a few hands were raised. (more of joke) In this process a more astrobiology rover or a more geology rover or a more geophysics rover might be the outcome strongly depending on the group selected to do the science definition. It's going to end up as astrobiology with sample caching for future Mars sample return. There is no way that they can build this rover and not have caching and still satisfy the Mars community. The Mars community is pretty united in support of sample return.
Quote from: Dalhousie on 12/07/2012 08:47 pmIs this true though? Launch costs are 5-10% of a planetary mission and well understood. It is the spacecraft that are expensive and most likely to suffer unreasonable cost growth.It is absolutely true. Consider that a Discovery class mission is approximately $500 million (recent ones have been in the $425-$450 million range). Launch vehicle costs are running $150 million. That is way more than 5-10% of the cost. And it means that three rockets are the equivalent of another mission.NASA did some budgetary shuffling to alleviate the direct pressure on individual programs by removing the vehicle cost from the Discovery and New Frontiers program caps. The reason was that vehicle costs were rising so fast that they were killing the principal investigators doing the missions. Suppose you are a PI on a Discovery mission and when you start building your spacecraft your Delta II is only going to cost $70 million, but by the time you get ready to launch, it has increased by $20 million. That has carved out $20 million that you could have used for your spacecraft. (Jim might have better numbers on this, but Delta II costs increased dramatically. I think that they more than doubled in a decade. Delta II was running at something like $60-$65 million in 2000, and probably like $120 million by 2009, as the result of the phase-out. Once it was phased out, even if you had a small spacecraft, you had to stick it atop a $150 million Atlas. And if you think this is bad, consider people in the Earth sciences and heliophysics, where they typically build a spacecraft for $250 million. You think they want to spend $150 million on a launch vehicle?)There are several recent missions, including Juno and New Horizons, that got slammed by those increases--not only Delta II going up in cost, but being forced to shift from a Delta II to the more expensive Atlas V because DII was being phased out.What NASA did in response was to lower the cost cap for the spacecraft (I don't know by how much) and remove the launch cost from the cap limit. That gave the PI less money, but insulated them from increasing launch vehicle costs. However, you can figure this out--NASA still had to pay the rising costs of the launch vehicles, so they ultimately do less missions.If you look in any report about the planetary science program produced in the last five years you will find that they discuss the negative impact of rising launch costs. It is a very big deal.
Thanks for this. I was thinking of MSL where the launch cost is (or was) only about 5%. But spacecraft cost is still the biggest component, and this suggests that it might be better to ry and reduce costs with these for a bigger impact.
This has been all very informative. But what have been the factors in driving up launch costs in recent years, why have launchers become so expensive?
If caching is involved, I am assuming that selecting a landing site for this rover pretty much also means picking the landing site for the followup sample return mission. If so, what limits does this put on site selections? Latitude? Terrain? Elevation of site?
http://solarsystem.nasa.gov/2013decadal/whitepapers.cfm?Category=MSIf it discovers something very interesting, we just might send the 2020 rover back to Gale Crater. Considering the increased complexity, they might start thinking about site selection now!
Quote from: Star One on 12/08/2012 10:03 pmThis has been all very informative. But what have been the factors in driving up launch costs in recent years, why have launchers become so expensive?I don't know this all that well. Jim might know, if he is reading this thread.There are several factors that I know of. Delta II infrastructure costs (like the pad) were covered by the USAF and so NASA really only had to pay for the launch vehicle. For reasons I don't understand, the Delta II costs started going up before the USAF stopped using the Delta II. They rose pretty rapidly too. Now I think I read somewhere that in some ways Delta II costs were actually artificially high because USAF had a rapid-launch requirement for Delta II in order to replace sick GPS satellites. That meant that they kept full crews on contract, etc. If USAF had dropped that requirement, then Boeing could have run a more efficient infrastructure for Delta II and the costs would have been lower for USAF. But once USAF decided not to cover the infrastructure costs at all, NASA got hit with the full expense. Like USAF, NASA moved to the Atlas V. USAF covers the infrastructure costs on Atlas and Delta, and NASA goes along for the ride.Atlas V and Delta IV costs started increasing rapidly several years ago. I don't know why. United Launch Alliance claims that the reason has to do with the "unfair" (my word, but that's what they imply) way in which the government contracts with them. There is some kind of requirement that they be able to guarantee costs and capabilities many years in advance, and this leads to ULA high-balling the costs to cover the possibility that things might be expensive for them and eat into their profit margin. I don't know about it, don't understand it. Lots of people claim that it really comes down to ULA having a monopoly on launches for the US government, so they can charge whatever the heck they want and don't need to try and keep things inexpensive. The recent announcement by USAF that they will buy at least three Falcon 9 launches in the next several years may help to break this monopoly. We'll see.But I'd rather not turn this into a discussion of the Falcon 9. As you may have seen elsewhere on this site, some people here think that the Falcon 9 has magical powers and can defeat Voldemoort, and I'm a little tired of their... enthusiasm.