Putting it at L2 gives a more consistent thermal environment and means it doesn't have to repoint as often, but doesn't really make it any cooler. (After all, it's just barely past the Earth) At equilibrium the hot side of the Webb is around 300K. (80F)
https://www.quora.com/Is-the-L2-point-of-Earth-in-a-permanen...
For reference, the melting point of nitrogen is, 63˚K.
Any sunlight at all would overwhelm this sensor and severely reduce the operational lifetime (and results!) of the telescope.
At L2, the telescope has the sun and the Earth behind a layered sunshield. It's easier to maintain position there and to have both objects always in the sol-ward direction while looking outwards.
Their point was that Starship has a big potential to significantly reduce cost by enabling the development of devices that are less optimized for size and weight. For example, the extremely expensive JWST could have been built with a much cheaper, non-foldable mirror, since the Starship fairing has a quite large diameter.
But they also argued that there is an unfortunate tendency in science to overoptimize everything, which leads to exploding cost. So it is well possible that scientists won't use Starship to reduce the cost of their spacecrafts, but to optimize them for maximum performance like they did before, e.g. by designing complex foldable mirrors which barely fit into the Starship fairing.
So I guess if they do that, Starship would enable an even stronger cost explosion than in the past, not a cost reduction. More available mass and size means more opportunity to spend money on complex engineering. The launch costs themselves are not a significant factor here.
Starship is monolithic right now, ie it’s unclear how it can unload payload of its own size. There are no bay doors a-la shuttle.
I guess they will have to do tilt-away nose section or something.
> The Starship payload fairing is a clamshell structure in which the payload is integrated. Once integrated, the clamshell fairing remains closed through launch up until the payload is ready to deploy. An example sequence of payload deployment is shown in Figure 3. To deploy the payload, the clamshell fairing door is opened, and the payload adapter and payload are tilted at an angle in preparation for separation. The payload is then separated using the mission-unique payload adapter. If there are multiple payloads on a single mission, a rotating mechanism can be provided to allow each satellite to separate with maximum clearance. Once separation is confirmed and the payload(s) have cleared the fairing, the payload fairing door is closed in preparation for Starship’s return to Earth.
Figure 3: https://i.stack.imgur.com/D3MYv.png
Full PDF: https://www.spacex.com/media/starship_users_guide_v1.pdf
That is a hilarious statement.
https://www.usaspending.gov/agency/national-aeronautics-and-...
Pretty sure there is no space organization which comes close.
https://www.youtube.com/watch?v=NQFqDKRAROI
A telescope array that can use our sun's gravitational lens would enable us to resolve the surfaces of extrasolar planets. We could resolve surface features as small as 10 km across at a distance of 100 light years.
JPL is actively investigating this. It's incredibly promising.
Orbital dockyards and asteroid mining would be in reach if Starship delivers on its (admittedly pretty steep) promises.
(I'm at the University of Washington Department of Astronomy, and work on telescope software).
You don't service cubesats, you just learn from your past mistakes and launch more.
It's kind of sad that the one real thing the Space Station demonstrated, assembly of large space structures, has been abandoned in the name of feeding the pork pipeline with SLS.
SLS will be delivering segments of Gateway after the first 2 are delivered by Falcon Heavy.
Eventually someone with a brain is going to notice, SLS will be canceled, and decades of federal jail time will ensue for the criminals who perpetuated this fraud upon the American people.
Edit:
The most significant thing Starship is bad at is launching and landing humans. Human launch systems like Falcon 9/Dragon or SLS/Orion have both a launch abort system and a highly reliable "blunt capsule" method of landing humans back on Earth. For Starship, both launching and landing humans is much more dangerous, as it doesn't have a launch abort system and it uses a complex maneuver ("belly flop") in order to land.
Starship will need to do a lot of unmanned satellite launches to prove a safety level acceptable for humans. Or people transfer to and from Starship in space, as in Artemis 3, and start/land with a different rocket.
A cost of $27,000,000,000 per launch, and a launch rate of 1 per 132 months is a generous definition of "works". And that's where SLS is right now.
Starship isn't just about price, but also fairing volume. And fairing volume is one of the major factors that drives telescope design.
It's even possible that SpaceX would do a limited run hammerhead fairing for the right price.
I'd imagine that a hammerhead fairing would mean an expended 2nd stage. There's just too much custom work that would have to be done (for example with the heat shield) to really make it work.
But if the cost is reasonable (I'm guessing ~$25 million for an upper stage), that isn't a bad price to pay to get access to a 12m fairing.
But NASA would pay much more than that if it means they can launch a telescope with a big mirror that doesn't need to be folded in. The main problem I see is that they would likely also have to pay for the entire development of the new upper stage, which would be much higher than the pure launch cost. Since NASA already has JWST, I'm not sure they have much interest in a big new space telescope currently. Other than that, it's not clear what a super large payload fairing would be required for.
I don't see why they'd need to do a full 2nd stage.
I'm sure a limited run fairing (especially a complicated one like a hammerhead) will be expensive - certainly quite a bit more than the $5 million per unit cost of the Falcon fairings. But ultimately a fairing just isn't that complicated, and SpaceX has a lot of experience with them.
that'll be initial cost submitted. once it is approved and work begins, that number will double, triple, or more before it is completed.
It’s amazing how wrong facts are asserted with absolute certainty here on HN.
That was what you responded to. Since when the upper stage is the payload? Which facts are you asserting?
Falcon 9 is around $60 million/launch (though when contracted by NASA or the military, launches tend to be 2x-4x the price). This is pretty much inline with what you get from Arianespace, and Roscosmos. There is no path to reduce price by another order of magnitude. We've pretty much hit the limit on what we can do with chemical rockets.
There is room to reduce cost much further. Discarding the second stage is a large cost. The propellants used by F9 cost $200K/launch, according to Musk. With full reusability costs should fall at least another order of magnitude.
Or they can't, because there are physical limits to the chemical rocket technology.
>There is room to reduce cost much further. Discarding the second stage is a large cost ... with full reusability costs should fall at least another order of magnitude.
Reusability is not a panacea. Falcon 9 is partially reusable and it is not significantly (if at all) cheaper than the competition. There is no evidence that full reusability will provide an order of magnitude cost decrease in prices. Fully reusable rockets imply that you're cutting into your cargo space (because you have to ship extra fuel for the decent), and maintenance is expensive and time-consuming. Don't get me wrong, there may be costs savings there, but not 10x, more like 10%.
Awfully coincidental it happens to cost just slightly less than than the competitors.
No, that's just you stupidly confusing price and cost.
There is downward pressure, we're just hitting physical limits on what can be done with chemical rockets.
The mere existence of the Starship design, which doesn't break any physical laws, shows your claim is nonsense.
Obviously wrong how? I saw that Musk was claiming that launch costs for starship will be around $1-2 million at some point - probably after hyperloop launches as a "5th mode of transport" in Neverland.