17 thoughts on “JWST”

  1. Yes. Space based optical (& otherwise) is the way to go…and in our soon to be era of reusable Starship sent aloft by equally reusable super-heavy rocket the sky is the limit. You could have a number of JWST type telescopes stretching across several hundred meters (or even eventually kilometers) working in concert delivering the approx. resolving power of one giant single telescope of the same size. Imagine the level of detail you could get from say an nearby Exo-planet like Teegarden-B:
    “Teegarden’s Star b orbits within the optimistic habitable zone of its host star. This means it is possible that its atmospheric composition could allow for stable liquid water on its surface.[4]

    Another factor for Teegarden’s Star b’s potential habitability is its host star. Most red dwarfs emit powerful flares, which can strip the atmospheres off their planets and cause them to be uninhabitable. A good example is Kepler-438b, which has an ESI score of 0.88, but because of its active star it is likely uninhabitable, and another example is Proxima Centauri, the closest star to us. However, Teegarden’s Star is relatively inactive and quiet, increasing the chance that Teegarden’s Star b may be habitable. ”


    At only about 12 ly from Earth you might not only get a detailed atmospheric analysis but probably continents, seas, large islands etc.

  2. Wonderful news, and I look forward to some good science.

    Despite which, it was absolutely not worth it. $10B and 30 years, and the opportunity cost of everything we COULD have done instead. This procurement disaster deserves to be studied for lessons in what not to do. Program leadership should resign now (should have been fired long ago), and everyone even peripherally involved at least owes a sheepish apology to every single long-suffering U.S. taxpayer.
    But of course that won’t happen. Instead this will be called a “success” which means we’ll get more like it.

  3. Talking Optical (and otherwise) Interferometry; already being done on Earth with various telescopes. Works better (theoretically) above the cloudy atmosphere of our planet.

  4. Let’s hope that what the JWT sees way back in time utterly astounds, confuses and baffles the astronomers.

  5. “But now that ultra complex heat shield is working. The temperature on the Sun-facing side of the telescope is 55 degrees Celsius, or a very, very, very hot day in the Sahara desert.”

    In terms of air temperature, there is no air in space.
    55 C ground temperature is common and could occur in the winter in the US. It’s actually quite cold in sunlight, the lunar surface is 120 C when the Sun is zenith. And it’s in zenith, but due to distant maybe about 118 C.

  6. Future instruments will be built in space.

    One of the reasons the whining about Starlink satellites messing with astronomical research is annoying is that most researchers don’t look through eyepieces, but look a screen showing what the eyepiece sees. (Or let their instruments look through it.) No reason that eyepiece can’t be in orbit.

    Business opportunity– manufacturing standarized small “space telescopes” which would be bought/leased/rented by researchers/educational institutions and launched in bulk. Does anyone know how a 10″ refractor (for example) in orbit would compare to one on the ground in the not-so-dark and humid skies of much of eastern North America or of Europe?

  7. The JWST has a 6.5 meter aperture. Starship v1.0 has a 9 meter maximum payload diameter. There are plenty of telescopes with 8 meter primary mirrors, such as

    the Subaru (8.2 meter aperture, 22.8 tonne primary, Corning ULE),

    the Large Binocular telescope (8.4 meter apertures, 17.7 tonne primaries, borosilicate),

    the Very Large Telescope (four 8.2 meter primaries, 22 tonnes each, Zerodur),

    Gemini North and South (8.1 meter, 22.2 tonnes each, Corning ULE-581)

    1. “The JWST has a 6.5 meter aperture. Starship v1.0 has a 9 meter maximum payload diameter.”

      So those other telescopes (theoretically anyway) could have been launched into space within your stated payload diameter max for the Starship? Given the advantages of being in space while I won’t ring the death knell for ground based astronomy, some things work better in space. Interferometry where telescopes could be spaced physically 100’s of meters (eventually km) apart have the magnification/resolving power of a single mirror that large have one drawback. The image is much fainter; so being above the atmosphere you have more light gathering ability. To say nothing of being able to detect/use wavelengths of EM radiation that the atmosphere attenuates.

      1. The latest 8-meter class single mirror telescope is almost complete.

        From the GAO:

        NSF was evaluating options for reducing the scope of the Vera C. Rubin Observatory (previously the Large Synoptic Survey Telescope), which it believed might be necessary to keep the project within its $473 million cost and October 2022 completion date.

        That’s a 20th of what the smaller JWST cost, and included in the price is a giant mounting and mountain-top observatory. I was looking for the cost of making the 8-meter mirror, but so far the closest figure I found was in a budget document

        Prior to NSF’s construction award, NSF, DOE, and private (non-federal) partners invested over $130.0 million in Rubin Observatory-related work. About 70 percent supported design and development. About 30 percent, from the non-federal funding, supported casting and polishing of the innovative combined primary-tertiary mirror (M1M3), initial site preparation, and prototype detector creation and evaluation, all of which significantly reduced construction risk.

        So making and polishing the mirror, and site preparation, were about $39 million. Assuming $20 million for a Starship launch, it’s apparent that someone with an eye on bang-for-the-buck could gets us some fantastic space telescopes at a much lower price.

    1. Astronomers: “JWST shows the universe is composed mostly of what cosmologists tell us is dark matter.”
      Cosmologists: “We can haz grants?”
      Me: “Every plant and animal that ever lived knew it was dark. I’ll try to keep my griping to myself for the rest of the day.”

  8. Kinda strange we are relying on the greed of people who spend other people’s money to make changes toward cost efficiency.

    Does anyone involved with JWST even care about the money and where it came from? How many have given public apologies? Anyone quit or get fired?

    It is great the costs were not literally sunk after launch but I feel anyone pimping this program should preface every statement with an apology.

    Will changes in fairing size change how government agents think in areas other than min/max? How will min/max be expressed with larger fairings? Will we soon be saying, “Just because you are in space, doesn’t mean you have to use all of it.”

    The problem with JWST had almost nothing to do with fairing size and almost everything to do with government agent ideology and that won’t be changing, so we can expect to see JWST type problems manifesting in other forms going forward.

  9. Reading across the Interdweebz, you see astronomical types, mostly anti-crewed-space-travel, dismissing the idea that Starship will allow them to reduce costs, coming up with reasons why no such solution will ever materialize. “Rather than wasting time thinking of how astronauts can repair Webb, think about how we can use that budget for the next telescope.” Although there is a faction that wants the next telescope to be a radiotelescope in a crater on the lunar farside.

    (Since I favor zeroing out the education budget top to bottom, I could see eliminating all government-funded research projects as well. “Is the end product a bomb? No? Maybe you can hold a bake sale for that.” Same for crewed space travel. You want to go to Mars? Bake sale? Name is Musk, you say. Just a minute while I fire the FAA for you.)

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