Fluidic Telescopes Could Breakthrough Cost Limits to 50 Meter Space Telescopes

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The future of space-based UV/optical/IR astronomy requires ever larger telescopes. A NASA NIAC Phase 1 study will look at a space observatory with a large-aperture (50-meter) unsegmented primary mirror suitable for a variety of astronomical applications. The mirror would be created in space via a novel approach based on fluidic shaping in microgravity, which has already been successfully demonstrated in a laboratory neutral buoyancy environment, in parabolic microgravity flights, and aboard the International Space Station (ISS). Theoretically scale-invariant, this technique has produced optical components with superb, sub-nanometer (RMS) surface quality.

In the Phase I study they will analyze suitable options for the key components of the 50-meter observatory, develop its detailed mission concept, and create an initial plan for a subscale small spacecraft demonstration in low Earth orbit (LEO).

The highest priority astrophysics targets, including Earth-like exoplanets, first-generation stars, and early galaxies, are all very faint, which presents a challenge for current and next-generation telescopes. Larger telescopes are one of the main (if not the main) way to address this issue.

One of the more important science questions Are we alone in the Universe? has been asked for thousands of years and features prominently in the Astro2020 decadal survey. We are fortunate to live at a time when technologies finally exist to begin answering it. Over the last three decades, a number of methods have been used to identify potentially habitable planets around other stars. James Webb Space Telescope (JWST) will perform some spectroscopic measurements of transiting exoplanet atmospheres, perhaps even detecting biomarker gases. The next NASA Astrophysics flagship mission (Roman) will do direct imaging spectroscopy of exoplanets, but it is not specifically designed for potentially habitable planets. The follow-on flagship recommended by the Astro2020 survey is planned to directly image 25 potentially Earth-like planets. However, the number of exoplanets on which life could be detected by the Astro2020 flagship is strongly limited by its aperture, which is planned to be ~6 meter.

With mission costs depending strongly on aperture diameter, scaling current space telescope technologies to aperture sizes beyond 10 meter does not appear economically viable. The 6-m Astro2020 flagship would already strain NASAs budget and its launch date is expected to be later than most astronomers would like (first half of the 2040s), largely driven by the substantial expected cost. Without a breakthrough in scalable technologies for large telescopes, future advances in astrophysics may slow down or even completely stall. Thus, there is a need for cost-effective solutions to scale space telescopes to larger sizes.

3 thoughts on “Fluidic Telescopes Could Breakthrough Cost Limits to 50 Meter Space Telescopes”

  1. I am a brute force guy…just accept the cost of SLS…and push for these old Ares V payloads:
    https://science.nasa.gov/science-news/science-at-nasa/2007/25jun_l2

    Scroll down to see the blurb about the 150 meter wide (492 foot) dish.

    I want that as the frame—with the MIT tech to smooth it out.

    If it doesn’t get quite to optical levels—you still have a hell of a dish for space-based radar with that metal frame behind it one way or another.

    Go for the two-fer:

    Another case in point—this sucker:
    https://up-ship.com/blog/?p=29354

    Snipe at hypersonics pointed down—-shoot cubesats with Excalibur shell electronics pointed out and up.

    The key is to actually have real space advocates run Space Force—and to hide projects behind the right name.

    The “Cislunar Highway Patrol System” is now “Oracle.”

    Sounds like a spysat program so the fiscal hawks might give it a pass.

    My next scheme is to convert SLS into an Energia/Buran type Shuttle 2 by calling it:
    Trans
    Atmospheric
    Xploration
    Capable
    Utility
    Transport
    System

    (TAXCUTS)

    I’ll have Marjorie-Gortner Taylor Jingle heimer Green introduce it as the MTG TAXCUTS program.

    “I need a hundred billion for TAXCUTS….voice vote only…”
    (-sound of Rand Paul choking)…

    Next up

    Deficit
    Ending
    Act
    To
    Healthy

    Spending
    That
    Alleviates
    Reaganomics

    Muahahaha!

  2. It actually would be nice to have an article carefully laying out the underlying telescope figuring (‘shaping’) technology. In the so-called micro-gravity of a stable parking orbit, be that at one of Sol’s Earth Lagrange points, or a Terra-Luna Lagrange orbit, or even an Asteroid Belt synchronous orbit … at any of those, the ‘micro’ part of micro-gravity ought to be thought of as nano- or pico- G’s. Quite micro indeed.

    I expect that a metallized polymer sheet spans a tensioning hoop, and is backed by noting at all. Parallel to it, and quite close, would be an array of hexagonal space-filled but quite hollow (think window screens) panels. The metallized film would carry a constant charge, which is easy enough. Say ‘positive’ for analysis. If the grids behind are negative, there WILL be a uniform attraction between the film and the grids, leading to an almost perfect parabolic figure.

    Having dozens, or hundreds of individual attractor panels would also allow them to be slightly different in charge, attracting the film in a way not unlike the aspheric correction ”adaptive optic corrector plate’ technology of large Terran telescopes. Thus, nanometer-scale parabolic corrections. That’d do the trick. Also, since the grid panels don’t exactly just sit 10 centimeters indefinitely from the film (film ages, stretches, has hot-cold cycles, is buffeted by the Solar wind, all that) Because of that the grids definitely need constant updates to maintain near-perfect parabolic figure.

    Anyway, that’d be my guess.
    Panel?

    GoatGuy

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