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You can tell from my username that I have some opinions in this area. My questions are these: NASA can barely keep JWST on a delayed schedule without massive

You can tell from my username that I have some opinions in this area. My questions are these: NASA can barely keep JWST on a delayed schedule without massive cost overruns. What is another telescope good for? How many astronomers and support staff do we need in this industry? How do we measure and know that it's enough? What's the breakthrough that another telescope at the cost of $Bs would achieve? (and please be specific if anyone is going to reply, not just the old "because it's worth doing" argument -- that could justify any amount of spending) These are the things you think about after you leave a field and are not beholden to it any more.

zrail 6y ago
A new space telescope will not be subject to Starlink interference. SpaceX will be happy to launch it for you at very competitive prices.
- dylan604 6y ago
  So that's the real purpose of Starlink, eh?
  - mschuster91 6y ago
    The real purpose is to offer planetary-wide 1 Gbit/s Internet access. Assuming SpaceX can keep up with the demand, this is definitely going to kill Iridium and probably all ISPs in rural areas where people these days are happy to have ISDN service (and I wish I were joking here). Also, given that a SpaceX sat dish is supposed to be the size of a pizza box which means incredibly hard to spot, it will open truly free (it will still be under the control/influence of the US government, though) Internet access worldwide... this is going to have a massive impact on China, North Korea and other countries where Internet freedom is severely restricted.
SiempreViernes 6y ago
Some of us wants to see further than the local neighbourhood man, why you gotta be so salty? In any case it's not like NASA funds ground based telescopes, so I'm not sure what you would want to happen instead, just more rockets in space with blinkenlights to mess up the Rubin frames?
justaguy88 6y ago
If starship becomes a real-go-to-orbit rocket, the cost to put this telescopes up there will go down, and they can likely use larger heavier materials to make the telescopes themselves, also reducing the cost a lot
- valuearb 6y ago
  Not sure why you are getting downvoted. The JWST is blowing through every possible budgetary limit because of the crazy lengths they have to go through to fold and unfold the sunscreen to fit a 4.5 meter fairing. Starship has a 10 meter fairing, so far less folding. It also can lift 5 times the mass of the Ariane 5, which would allow including heavier and tougher materials for the sunscreen (which has already torn once in testing), far more fuel for station keeping to extend its ten year life span by decades. Even better, Starships 10 meter fairing would allow launch an actual 6.5 meter mirror instead of one built out of 18 smaller segments. The reduction in complexity is immense. Lastly, Starship makes a JWST style observatory serviceable, even a million miles out at Earths L2 Lagrange point. That in itself makes for a longer life span, and regular upgrades, simplifying design decisions even more.
flyinglizard 6y ago
1. Broader observation spectrum (IIRC JWST is visible red to infra red) 2. Machine time for researchers (I don't know how congested Hubble is but humanity could use more than a single telescope) 3. Redundancy in case JWST goes up in flames and we're left without a space telescope
- SiempreViernes 6y ago
  WFIRST is infrared and optical too, maybe there are a few nm and micrometers more or less in one or the other, but both are essentially covering the same wave lengths.
dsl 6y ago
> What's the breakthrough that another telescope at the cost of $Bs would achieve Neither will go to space. They are late-70s early-80s spy sats. This was a technology transfer so NASA could learn how NRO solved specific challenges they faced. There was talk at the time about one of them being sent up in 2024, but that hasn't even been discussed seriously in the last 8 years.
- ngoldbaum 6y ago
  That’s not true, the bus and mirror will be used by WFIRST: https://en.m.wikipedia.org/wiki/Wide_Field_Infrared_Survey_Telescope https://en.m.wikipedia.org/wiki/Wide_Field_Infrared_Survey_T...
  - dsl 6y ago
    WFIRST-AFTA keeps getting budget, and that budget keeps getting diverted to the James Webb Space Telescope. Two years ago they issued the first production contracts, targeting a delivery date of 2025. Now we are looking at putting 50 year old parts in to space, at best.
deleted 6y ago
[deleted]
Rebelgecko 6y ago
> What is another telescope good for? My understanding is that WFIRST is more of a replacement for Hubble as it slowly dies (or suddenly dies at the end of a fiscal year due to $$$). However compared to both JWST and Hubble, it has a much higher field of view (the example that NASA gave at one point is that took the Hubble several years to survey the Andromeda Galaxy in IR. WFIRST could do that same job in a few hours). This has a lot of benefits if you want to do things like look for exoplanets. WFIRST will of course be very expensive, but for a number of reasons it is unlikely that it will be even close to the cost of JWST (like JWST it will be going to the L2 Lagrange point, but it won't have to make as many design compromises as JWST to get there) The last decadal survey of astronomers[1] determined that WFIRST was a #1 priority because: "...WFIRST will settle fundamental questions about the nature of dark energy, the discovery of which was one of the greatest achievements of U.S. telescopes in recent years. It will employ three distinct techniques—measurements of weak gravitational lensing, supernova distances, and baryon acoustic oscillations— to determine the effect of dark energy on the evolution of the universe. An equally important outcome will be to open up a new frontier of exoplanet studies by monitoring a large sample of stars in the central bulge of the Milky Way for changes in brightness due to microlensing by intervening solar systems. This census, combined with that made by the Kepler mission, will determine how common Earth-like planets are over a wide range of orbital parameters. It will also, in guest investigator mode, survey our galaxy and other nearby galaxies to answer key questions about their formation and structure, and the data it obtains will provide fundamental constraints on how galaxies grow. The telescope exploits the important work done by the joint DOE/NASA design team... and expands its scientific reach. WFIRST is based on mature technologies with technical risk that is medium low and has medium cost and schedule risk... WFIRST will complement the targeted infrared observations of the James Webb Space Telescope. The small field of view of JWST would render it incapable of carrying out the prime WFIRST program of dark energy and exoplanet studies, even if it were used exclusively for this task. The recommended schedule has a launch data of 2020 with a 5-year baseline mission. An extended 10-year mission could improve the statistical results and further broaden the science program. The European Space Agency (ESA) is considering an M-class proposal, called Euclid, with related goals. Collaboration on a combined mission with the United States playing a leading role should be considered so long as the committee’s recommended science program is preserved and overall cost savings result." >How many astronomers and support staff do we need in this industry? I'm going to be honest, this comes across as a bit of a loaded question. Obviously we don't "need" any astronomers at all (or most scientists for that matter). But more theoretical research can still have tremendous payoffs. I'm a big fan a letter[2] that a paperclip'd director at NASA Marshall wrote to a nun in Zambia who asked why the US spends billions going to the moon while children on Earth starve to death. >How do we measure and know that it's enough? I don't think humanity will reach a point in any scientific endeavor where we decide that it's enough and we don't need to understand any more. I suppose it would be when we have a complete understanding of the entire universe. [1]: https://science.nasa.gov/astrophysics/special-events/astro2010-astronomy-and-astrophysics-decadal-survey/ https://science.nasa.gov/astrophysics/special-events/astro20... [2]: https://lettersofnote.com/2012/08/06/why-explore-space/ https://lettersofnote.com/2012/08/06/why-explore-space/
cryptonector 6y ago
Well, this donation == lots of saved money. That's probably why NASA comes across as a bit less than grateful.
mturmon 6y ago
The WFIRST web page gives a good description: https://www.jpl.nasa.gov/missions/wide-field-infrared-survey-telescope-wfirst/ https://www.jpl.nasa.gov/missions/wide-field-infrared-survey... There are 2 instruments. The coronagraph instrument (“WFIRST-CGI”) is a high contrast imaging test bed. If we want to have a technology path to image exoplanets, we need to test and improve the tech we have for masking the starlight of a target star, while allowing us to see the reflected light from a nearby exoplanet. For earth like exoplanets, this is a 10^10 brightness difference. WFIRST will hopefully get us to 10^8. To get there, you need deformable mirrors, wavefront sensing, and active control. We will also be able to get coarsely binned spectra from WFIRST. Spectra (in general — I’m not sure if WFIRST will get there) would allow us to detect presence of water absorption features in the reflected light. Eventually, we might be able to sense the oxygen A and B bands, which would indicate non-equilibrium chemistry.
magicalhippo 6y ago
> What's the breakthrough that another telescope at the cost of $Bs would achieve? Multi-messenger astronomy[1] seems to be the next big thing. Will we lose out if we don't have a good optical telescope "up there"? Or is the current crop of gamma/x-ray and IR satellite telescopes coupled with ground-based optical telescopes good enough? I understand adaptive optics and such has drastically improved the capabilities of ground-based telescopes, but for MMA (to hijack the acronym) are there any advantages of a space-based optical telescope? [1]: https://arxiv.org/abs/1710.05833 https://arxiv.org/abs/1710.05833
xxpor 6y ago
I'll argue the other side of the "because its worth doing" argument: 10 billion dollars just isn't that much money. It's very roughly one Amazon Seattle campus or half of the cost of the 2nd Ave subway in Manhattan. People are lending us money for basically free, might as well spend it on fun stuff rather than blowing people up.
- valuearb 6y ago
  $10B is enough to send over 100 astronauts to Mars for multi year stays. I’m guessing the science they produce will be much more actionable in the short run, and the reusable, orbital refuelable space ship used to transport them to Mars will also cut the cost of launching space telescopes by ten times.

zrail 6y ago

A new space telescope will not be subject to Starlink interference. SpaceX will be happy to launch it for you at very competitive prices.

dylan604 6y ago
So that's the real purpose of Starlink, eh?
- mschuster91 6y ago
  The real purpose is to offer planetary-wide 1 Gbit/s Internet access. Assuming SpaceX can keep up with the demand, this is definitely going to kill Iridium and probably all ISPs in rural areas where people these days are happy to have ISDN service (and I wish I were joking here). Also, given that a SpaceX sat dish is supposed to be the size of a pizza box which means incredibly hard to spot, it will open truly free (it will still be under the control/influence of the US government, though) Internet access worldwide... this is going to have a massive impact on China, North Korea and other countries where Internet freedom is severely restricted.

SiempreViernes 6y ago

Some of us wants to see further than the local neighbourhood man, why you gotta be so salty? In any case it's not like NASA funds ground based telescopes, so I'm not sure what you would want to happen instead, just more rockets in space with blinkenlights to mess up the Rubin frames?

justaguy88 6y ago

If starship becomes a real-go-to-orbit rocket, the cost to put this telescopes up there will go down, and they can likely use larger heavier materials to make the telescopes themselves, also reducing the cost a lot

valuearb 6y ago
Not sure why you are getting downvoted. The JWST is blowing through every possible budgetary limit because of the crazy lengths they have to go through to fold and unfold the sunscreen to fit a 4.5 meter fairing. Starship has a 10 meter fairing, so far less folding. It also can lift 5 times the mass of the Ariane 5, which would allow including heavier and tougher materials for the sunscreen (which has already torn once in testing), far more fuel for station keeping to extend its ten year life span by decades. Even better, Starships 10 meter fairing would allow launch an actual 6.5 meter mirror instead of one built out of 18 smaller segments. The reduction in complexity is immense. Lastly, Starship makes a JWST style observatory serviceable, even a million miles out at Earths L2 Lagrange point. That in itself makes for a longer life span, and regular upgrades, simplifying design decisions even more.

flyinglizard 6y ago

1. Broader observation spectrum (IIRC JWST is visible red to infra red) 2. Machine time for researchers (I don't know how congested Hubble is but humanity could use more than a single telescope) 3. Redundancy in case JWST goes up in flames and we're left without a space telescope

SiempreViernes 6y ago
WFIRST is infrared and optical too, maybe there are a few nm and micrometers more or less in one or the other, but both are essentially covering the same wave lengths.

dsl 6y ago

> What's the breakthrough that another telescope at the cost of $Bs would achieve Neither will go to space. They are late-70s early-80s spy sats. This was a technology transfer so NASA could learn how NRO solved specific challenges they faced. There was talk at the time about one of them being sent up in 2024, but that hasn't even been discussed seriously in the last 8 years.

ngoldbaum 6y ago
That’s not true, the bus and mirror will be used by WFIRST: https://en.m.wikipedia.org/wiki/Wide_Field_Infrared_Survey_Telescope https://en.m.wikipedia.org/wiki/Wide_Field_Infrared_Survey_T...
- dsl 6y ago
  WFIRST-AFTA keeps getting budget, and that budget keeps getting diverted to the James Webb Space Telescope. Two years ago they issued the first production contracts, targeting a delivery date of 2025. Now we are looking at putting 50 year old parts in to space, at best.

deleted 6y ago

[deleted]

Rebelgecko 6y ago

> What is another telescope good for? My understanding is that WFIRST is more of a replacement for Hubble as it slowly dies (or suddenly dies at the end of a fiscal year due to $$$). However compared to both JWST and Hubble, it has a much higher field of view (the example that NASA gave at one point is that took the Hubble several years to survey the Andromeda Galaxy in IR. WFIRST could do that same job in a few hours). This has a lot of benefits if you want to do things like look for exoplanets. WFIRST will of course be very expensive, but for a number of reasons it is unlikely that it will be even close to the cost of JWST (like JWST it will be going to the L2 Lagrange point, but it won't have to make as many design compromises as JWST to get there) The last decadal survey of astronomers[1] determined that WFIRST was a #1 priority because: "...WFIRST will settle fundamental questions about the nature of dark energy, the discovery of which was one of the greatest achievements of U.S. telescopes in recent years. It will employ three distinct techniques—measurements of weak gravitational lensing, supernova distances, and baryon acoustic oscillations— to determine the effect of dark energy on the evolution of the universe. An equally important outcome will be to open up a new frontier of exoplanet studies by monitoring a large sample of stars in the central bulge of the Milky Way for changes in brightness due to microlensing by intervening solar systems. This census, combined with that made by the Kepler mission, will determine how common Earth-like planets are over a wide range of orbital parameters. It will also, in guest investigator mode, survey our galaxy and other nearby galaxies to answer key questions about their formation and structure, and the data it obtains will provide fundamental constraints on how galaxies grow. The telescope exploits the important work done by the joint DOE/NASA design team... and expands its scientific reach. WFIRST is based on mature technologies with technical risk that is medium low and has medium cost and schedule risk... WFIRST will complement the targeted infrared observations of the James Webb Space Telescope. The small field of view of JWST would render it incapable of carrying out the prime WFIRST program of dark energy and exoplanet studies, even if it were used exclusively for this task. The recommended schedule has a launch data of 2020 with a 5-year baseline mission. An extended 10-year mission could improve the statistical results and further broaden the science program. The European Space Agency (ESA) is considering an M-class proposal, called Euclid, with related goals. Collaboration on a combined mission with the United States playing a leading role should be considered so long as the committee’s recommended science program is preserved and overall cost savings result." >How many astronomers and support staff do we need in this industry? I'm going to be honest, this comes across as a bit of a loaded question. Obviously we don't "need" any astronomers at all (or most scientists for that matter). But more theoretical research can still have tremendous payoffs. I'm a big fan a letter[2] that a paperclip'd director at NASA Marshall wrote to a nun in Zambia who asked why the US spends billions going to the moon while children on Earth starve to death. >How do we measure and know that it's enough? I don't think humanity will reach a point in any scientific endeavor where we decide that it's enough and we don't need to understand any more. I suppose it would be when we have a complete understanding of the entire universe. [1]: https://science.nasa.gov/astrophysics/special-events/astro2010-astronomy-and-astrophysics-decadal-survey/ https://science.nasa.gov/astrophysics/special-events/astro20... [2]: https://lettersofnote.com/2012/08/06/why-explore-space/ https://lettersofnote.com/2012/08/06/why-explore-space/

cryptonector 6y ago

Well, this donation == lots of saved money. That's probably why NASA comes across as a bit less than grateful.

mturmon 6y ago

The WFIRST web page gives a good description: https://www.jpl.nasa.gov/missions/wide-field-infrared-survey-telescope-wfirst/ https://www.jpl.nasa.gov/missions/wide-field-infrared-survey... There are 2 instruments. The coronagraph instrument (“WFIRST-CGI”) is a high contrast imaging test bed. If we want to have a technology path to image exoplanets, we need to test and improve the tech we have for masking the starlight of a target star, while allowing us to see the reflected light from a nearby exoplanet. For earth like exoplanets, this is a 10^10 brightness difference. WFIRST will hopefully get us to 10^8. To get there, you need deformable mirrors, wavefront sensing, and active control. We will also be able to get coarsely binned spectra from WFIRST. Spectra (in general — I’m not sure if WFIRST will get there) would allow us to detect presence of water absorption features in the reflected light. Eventually, we might be able to sense the oxygen A and B bands, which would indicate non-equilibrium chemistry.

magicalhippo 6y ago

> What's the breakthrough that another telescope at the cost of $Bs would achieve? Multi-messenger astronomy[1] seems to be the next big thing. Will we lose out if we don't have a good optical telescope "up there"? Or is the current crop of gamma/x-ray and IR satellite telescopes coupled with ground-based optical telescopes good enough? I understand adaptive optics and such has drastically improved the capabilities of ground-based telescopes, but for MMA (to hijack the acronym) are there any advantages of a space-based optical telescope? [1]: https://arxiv.org/abs/1710.05833 https://arxiv.org/abs/1710.05833

xxpor 6y ago

I'll argue the other side of the "because its worth doing" argument: 10 billion dollars just isn't that much money. It's very roughly one Amazon Seattle campus or half of the cost of the 2nd Ave subway in Manhattan. People are lending us money for basically free, might as well spend it on fun stuff rather than blowing people up.

valuearb 6y ago
$10B is enough to send over 100 astronauts to Mars for multi year stays. I’m guessing the science they produce will be much more actionable in the short run, and the reusable, orbital refuelable space ship used to transport them to Mars will also cut the cost of launching space telescopes by ten times.