Author Topic: Wide Field Infrared Survey Telescope (WFIRST)  (Read 22280 times)

Online meberbs

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #100 on: 08/09/2017 06:52 PM »
That letter is remarkable in how little of the original article it actually addresses.

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NASA has not yet completed the work of estimating the costs of the mission and is not facing funding difficulties, let alone a crisis.
Nothing in the article suggested that WFIRST was currently short of funds.
I don't think the title of the article counts as "little." That sentence you quoted refers directly to the title of the article. Of course the article doesn't actually support the title if you only look at the facts. The article does carry on the general tone of the title though, implying that a review to make sure cost and scope are in alignment is not a standard part of early project development. Every engineering project needs to balance cost, schedule, and scope.

Offline Blackstar

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #101 on: 08/09/2017 10:55 PM »
implying that a review to make sure cost and scope are in alignment is not a standard part of early project development. Every engineering project needs to balance cost, schedule, and scope.

For the past seven years or so, NASA has been pretty good at keeping its science missions on cost and schedule. But nobody has forgotten JWST, and I think that it is entirely prudent for NASA to want to make sure that its next large telescope project after JWST is carefully evaluated early on. So this review really isn't all that surprising.

Offline Khadgars

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #102 on: 08/09/2017 11:16 PM »
This is a fundamental problem with our funding approach - if you price something at what it's going to cost, it'll never get funded.  If you price it to get funded, you're going to get criticized - or cut - when it ends up costing what it actually costs.

Except your phrasing assumes that it is easy to know what something is going to cost. It's not. These are estimates based upon a lot of unknowns, with a lot of assumptions and large error bars.

Disavow yourself of the belief that everybody is lying and deceitful and just trying to get something approved so that they can blow the budget later. I realize that's the stereotype, but the real world is not so clear-cut. This is a complicated and iterative process, meaning that they estimate, they proceed, then they estimate again. There are ways to improve the accuracy of that process, but it's not possible to create an entirely accurate estimate of costs for many of these things. (Oh, and it is the same way in business too, they just don't air their dirty laundry.)

Also, cost is an important factor, but it is not the only factor, nor is it necessarily the most important factor. That's true in everyday life too. If it wasn't, then everybody would drive only inexpensive cars.

I know this was posted at the beginning of the year, but well said Blackstar.  One of my favorite posts.

Offline Blackstar

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #103 on: 08/10/2017 01:23 AM »
In another week I'll be able to post more about the cost estimation issue. I know it's the kind of thing that makes people roll their eyes or fall asleep, but if you're interested in programs getting done effectively, and you want to see the most happen (i.e. the best bang for your buck), then it helps to have a basic understanding of how this stuff is done and what are the latest developments.

Online hop

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #104 on: 08/10/2017 04:06 AM »
I don't think the title of the article counts as "little." That sentence you quoted refers directly to the title of the article.
It refers to a misinterpretation of the title which should be very obvious to anyone who read the article.

Quoting from the article
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The new study will help NASA evaluate how to preserve as much of WFIRST’s scientific capability as possible while remaining within budget, says John Gagosian, the mission’s programme executive at NASA headquarters in Washington DC. But he sees no reasonable scenario “in which the current mission scope and requirements (including the coronagraph) can be implemented for $3.2 billion or less”.
(my bold)
In other words, there's significant reason to believe NASA can't do all the things it wants to do with the amount of money it wants to spend. It should be clear this is the "cost crisis" identified in the title. Losing the coronagraph for example would be a major setback.

You can argue the headline is sensationalized, but it's very clearly referring to the apparent trajectory of the programs cost and requirements, not some current overrun.

To rebut this, Zurbuchen states
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NASA has not yet completed the work of estimating the costs of the mission and is not facing funding difficulties, let alone a crisis.
Technically true, but the crisis rebutted bears no resemblance to the one described. Worse, it implies the author made an egregious factual error (a cost overrun on a program that hasn't even been funded!) that they did not.

From the article:
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Last August, a review of NASA’s progress towards its 2010 decadal priorities singled out WFIRST as at risk of ballooning costs.
(my bold again)

And from Zurbuchen
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This review was recommended by the National Academies in 2014 and again in 2016, and is not motivated by the mission's current status.
No doubt technically true, but clearly avoiding the fact that WFIRST was singled out for concern by the last review, and subject to concern by others involved.

Online meberbs

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #105 on: 08/10/2017 02:43 PM »
I don't think the title of the article counts as "little." That sentence you quoted refers directly to the title of the article.
It refers to a misinterpretation of the title which should be very obvious to anyone who read the article.
There is simply not a crisis of any sort whatsoever, so rebutting the typical understanding of "cost crisis" seems like the appropriate response.

In other words, there's significant reason to believe NASA can't do all the things it wants to do with the amount of money it wants to spend. It should be clear this is the "cost crisis" identified in the title. Losing the coronagraph for example would be a major setback.
Scientists can't do everything they want because of cost constraints? That is simply a fact of life. There are multiple ways to deal with this even if this is the case. I have no idea how or why you are jumping to the "lose the coronagraph" scenario. Also the coronagraph was an addition, not part of the original mission proposal, so calling losing a bonus feature (however useful) a "major setback" doesn't make sense.

You can argue the headline is sensationalized, but it's very clearly referring to the apparent trajectory of the programs cost and requirements, not some current overrun.
To rebut this, Zurbuchen states
Quote
NASA has not yet completed the work of estimating the costs of the mission and is not facing funding difficulties, let alone a crisis.
Technically true, but the crisis rebutted bears no resemblance to the one described. Worse, it implies the author made an egregious factual error (a cost overrun on a program that hasn't even been funded!) that they did not.
It is beyond sensationalized, and is flat out wrong. The use of the would crisis in any sense except "no crisis" is wrong. Specifically referring to a cost crisis when the cost estimation hasn't even been completed doesn't even make sense, and you are now talking about the "apparent trajectory" of a program that is still too early to do any reasonable estimate of its overall performance.

From the article:
Quote
Last August, a review of NASA’s progress towards its 2010 decadal priorities singled out WFIRST as at risk of ballooning costs.
(my bold again)

And from Zurbuchen
Quote
This review was recommended by the National Academies in 2014 and again in 2016, and is not motivated by the mission's current status.
No doubt technically true, but clearly avoiding the fact that WFIRST was singled out for concern by the last review, and subject to concern by others involved.
How is it avoiding the issue when they are clearly pointing out that the review was recommended twice?

It is a large program, and all large programs are at risk of spiraling costs if they aren't carefully managed. NASA is clearly countering the implication by the article that the review is based on something specific to this program, rather than dealing with typical planning and scope creep that happens on all programs of this size. It was "singled out" for being a large program.

If you go look at the reasons stated for requesting the review (summary here) you will see that the recommendation was simply to review scope creep to make sure that the benefits are worth the associated costs.

Offline as58

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #106 on: 08/10/2017 04:09 PM »
It is beyond sensationalized, and is flat out wrong. The use of the would crisis in any sense except "no crisis" is wrong. Specifically referring to a cost crisis when the cost estimation hasn't even been completed doesn't even make sense, and you are now talking about the "apparent trajectory" of a program that is still too early to do any reasonable estimate of its overall performance.

Tangentially related to this, the Nature News article also repeats the story of JWST cost growing from $1 billion to current $8.8 billion, but that's not really a fair comparison. That $1 billion was not a real cost estimate, just some sort of notional 'cost wish' and when JWST was approved, it was clear that the price tag was going to be much higher. Sure, even after that JWST has gone through huge cost growth (IIRC the cost estimate before moving to phase C was close to $4 billion), but it's not quite as ridiculous as some stories make it sound.


Offline Blackstar

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #107 on: 08/10/2017 05:50 PM »
Tangentially related to this, the Nature News article also repeats the story of JWST cost growing from $1 billion to current $8.8 billion, but that's not really a fair comparison. That $1 billion was not a real cost estimate, just some sort of notional 'cost wish' and when JWST was approved, it was clear that the price tag was going to be much higher. Sure, even after that JWST has gone through huge cost growth (IIRC the cost estimate before moving to phase C was close to $4 billion), but it's not quite as ridiculous as some stories make it sound.

I agree with all this. But there's a big "however" in this story, and that also provides an important lesson for all large missions that start out in decadal surveys, not just astronomy ones, but the other science divisions as well.

The "however" is how those early estimates were generated. There's a lot of finger-pointing about this. The astronomers say that NASA gave them that original cost estimate and told them to use it. Some NASA people say that it was the astronomers who put a low-balled estimate in their decadal survey and said "do this mission." Hopefully somebody has interviewed the participants and asked about how this happened. But one result of all that was that Congress then required an independent pseudo-cost estimation process for the decadal surveys to serve as a sort of sanity check on the missions that were being considered. That became the Cost And Technical Evaluation (CATE) process. It is not perfect, for lots of reasons. But the powers that be determined that it was necessary in order to box in the costs and not simply accept the costs produced by mission advocates (even if those advocates were in NASA themselves--one of the most guilty culprits in lowballing JWST was the NASA administrator at the time).

The bigger issue is one that is somewhat difficult to describe, but it comes down to this: the scientific community prioritizes large missions based upon a very preliminary cost estimate, and they make assumptions about the rest of their portfolio of other things (smaller missions, research and analysis funding, etc.) based upon that preliminary cost estimate. But then NASA initiates a mission and only much later (usually years later) discovers that the cost of that mission is going to be much greater than what everybody thought when they produced the decadal survey. Now if NASA goes ahead with that expensive mission--and usually it is impossible to stop it at that point--then that much costlier mission can do a lot of damage to the rest of the portfolio, damage that the scientific community never would have agreed to in the first place.

So how do you deal with that? Well, the typical NASA response is by introducing processes for checking up on those issues at multiple points. One of those processes is to go back to the National Academies that produced the decadal survey and say "The mission was originally costed at $X, and now it costs $X+1. Is it still worth doing that mission?" That's sorta what you have seen with WFIRST, with NASA asking the astronomy community several times "Do you really want this mission?" Another process can be done at the decadal survey stage itself, when a decadal survey introduces decision rules concerning cost. You saw that with the last planetary decadal survey, which clearly stated that NASA should not pursue the Mars caching rover if it cost more than $2.5 billion. Notably, NASA has sought to keep the cost at $2.4 billion. Another decision rule was to de-scope the Europa orbiter mission to make it more affordable.

Note that this is not a perfect system. One of the reasons is that large missions gather momentum fast, so it is unlikely that a group of scientists is going to say "We changed our minds and that big thing is no longer worth it." Most likely what they will say is "That big thing is still important, but keep costs under control by doing A, B and C." Not a perfect system, but there are no perfect systems.

NASA has gotten better at all of this for a bunch of reasons. Like I said, I'll be able to share more about this later.


Offline Kansan52

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #108 on: 08/10/2017 06:11 PM »
Thank you. An excellent lesson. It allows a much better perspective on this issues. At least for me!!

Offline Blackstar

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #109 on: 08/11/2017 01:44 AM »
So wait... did anybody ask about the CATE process? Sure, you want to know about that.

CATE stands for Cost And Technical Evaluation, and so far The Aerospace Corporation has done this for all the decadal surveys since 2010. One of the key things to understand about CATE is that it is not simply an independent cost estimate. It also includes a technical evaluation of the proposal--meaning determining how mature the technology is. And it includes the "threats" to the program based upon historical data.

This latter point is really hard for people to understand, but it goes something like this: you can do an independent cost estimate of how much a space mission will cost, and that estimate is going to include an error budget. It's going to take into account that you cannot predict exactly what something will cost, but you can get close. But that is based upon the assumption that you are totally in control of the mission and only you affect the outcome.

And it turns out that the real world does not work like that. All kinds of external factors can affect the cost. You can be a total trooper and do everything right, and then Congress comes along and gives you 20% less money than you need one year and that blows your budget to smithereens. Not your fault, for sure, but it does affect the final cost of the mission, driving it up. The CATE process attempts to take that into account, and the result is that the CATE estimate is always going to be higher than an independent cost estimate that does not make that assumption. This makes a lot of mission advocates angry, because they look at the high CATE estimate and they say "That's not legit! That's too high! I can build the spacecraft for a lot less than that!" And in fact, the advocate may be able to do that, but not always. And for planning purposes, you want to budget what you are most likely going to need, not an overly optimistic estimate.

The criticism of the CATE is that it is preventing good missions from getting approved because they're being ruled out early because of their high costs, which is really only an educated guess. Well, although there's some validity to that criticism, you have to remember two things: 1-the CATE was introduced because a couple of projects (JWST and MSL/Curiosity) went way over-budget and sucked money out of adjacent programs and that was bad, and 2-the decadal surveys are aware of this and they consider it when they make their recommendations. The best example I am familiar with is the planetary decadal's New Frontiers proposal for a comet cryogenic sample return mission. When we did the CATE for that, it came in rather high (I think it was something like $1.3 billion). That was $300 million over our New Frontiers recommended cost cap of $1 billion. But we still included that mission in New Frontiers, because we thought that there is a reasonable possibility that somebody could propose a mission that comes in under the cost cap, and we were willing to let them try.

Online hop

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #110 on: 08/11/2017 04:17 AM »
I have no idea how or why you are jumping to the "lose the coronagraph" scenario.
Based on a direct quote from the NASA program executive which suggests that is a likely outcome. Notably, Zurbuchen's rebuttal didn't dispute that statement, or indeed address it at all.
Quote
Also the coronagraph was an addition, not part of the original mission proposal, so calling losing a bonus feature (however useful) a "major setback" doesn't make sense.
Depends what you mean by "original". It wasn't part of the original decadal recommendation, but it has been part of the baseline mission being developed by NASA since 2015 (though considered descopable)

Quoting from New Worlds, New Horizons: A Midterm Assessment

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At NASA’s direction, the 2015 SDT report adopted the coronagraph as a (descopable) part of the baseline WFIRST-AFTA mission, rather than an optional addition, and adopted a 6-year prime mission lifetime.

The report also notes that addition of the coronagraph helped the mission gain congressional and community support. The public and congress are a lot more excited about exoplanets than cosmology, and a lot of astronomers are excited about them too.

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It was "singled out" for being a large program.
The review was recommended specifically in response to how WFIRST has evolved into a much higher risk concept than the one in the decadal, not for being large.

I noted Zurbuchen's statement omitted important context. It appears those omissions may have lead you to incorrect conclusions.

Offline Nomadd

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #111 on: 08/11/2017 06:01 AM »
 I miss JIMO.

Online meberbs

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #112 on: 08/11/2017 02:20 PM »
I have no idea how or why you are jumping to the "lose the coronagraph" scenario.
Based on a direct quote from the NASA program executive which suggests that is a likely outcome. Notably, Zurbuchen's rebuttal didn't dispute that statement, or indeed address it at all.
No, the quote only says that he expects the cost with coronograph to exceed $3.2 billion, jumping to "lose the coronograph" is entirely on you.

Quote
It was "singled out" for being a large program.
The review was recommended specifically in response to how WFIRST has evolved into a much higher risk concept than the one in the decadal, not for being large.
As I said: scope creep. If you have an example of a large program that didn't suffer from this please share.

Also, you have not addressed my main point and the apparent main point of the response to the article: claiming there is a "cost crisis" is simply wrong.

Online hop

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #113 on: 08/11/2017 10:02 PM »
No, the quote only says that he expects the cost with coronograph to exceed $3.2 billion, jumping to "lose the coronograph" is entirely on you.
The jump from that number to concluding the coronograph is at serious risk is very small, because it has to square with recommendation 4-1 in the report. Or NASA has to ignore the recommendation and cannibalize the rest of the astro budget.

Really, read the whole WFIRST chapter, it's a fascinating and complicated story.
Quote
Also, you have not addressed my main point and the apparent main point of the response to the article: claiming there is a "cost crisis" is simply wrong.
Whether it merits the word "crisis" is subjective, but IMHO it's pretty clear that the WFIRST concept that NASA  developed and sold to Congress and the community over the last few years is in trouble. Hopefully they will find a way to keep it on track with a minimum of pain.

Offline Kesarion

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #114 on: 09/04/2017 08:34 AM »
https://exoplanets.nasa.gov/news/1452/nasa-team-passes-major-technological-milestone-for-characterizing-exoplanets/

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NASA team passes major technological milestone for characterizing exoplanets

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Working in concert with the coronagraph, an integral field spectrograph, or IFS, such as PISCES, would be able to separate the exoplanet’s light by its wavelength and record the data, revealing details about the planet’s physical properties, including the chemical composition and structure of its atmosphere.

Quote
“We are not done yet and are still trying to get to higher contrasts, but the 100 million-to-one over 18 percent of the optical wavelength band is an important and significant milestone,” said Maxime Rizzo, a postdoctoral student who is working with McElwain and his team to advance PISCES. “With the increased bandpass, we can get many colors at once. This enables us to identify more molecules in the atmospheres and get a big picture.”

Online hop

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Re: Wide Field Infrared Survey Telescope (WFIRST)
« Reply #115 on: 09/11/2017 06:08 AM »
Solar System science with the Wide-Field InfraRed Survey Telescope (WFIRST)

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We present a community-led assessment of the capabilities of NASA's Wide Field InfraRed Survey Telescope (WFIRST) for Solar System science. WFIRST will provide imaging and spectroscopic capabilities from 0.6-2.0 μm and will be a potential contemporary and eventual successor to JWST. Observations of asteroids, the giant planets and their satellites, Kuiper Belt Objects, and comets will be possible through both the Guest Investigator (GI) and Guest Observer (GO) programs. Surveys of minor bodies and time domain studies of variable surfaces and atmospheres are uniquely well-suited for WFIRST with its 0.28 deg2 field of view. Previous use of astrophysics assets for Solar System science and synergies between WFIRST, LSST, and JWST are discussed. We also provide a list of proposed minor modifications to the mission, including non-sidereal tracking of 30 mas/s and a K-band filter (∼2.0-2.4 μm).


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