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The most complete plan for this was proposed by JPL's Slava Turyshev and team. It has been selected for Phase III of NASA Innovative Advanced Concepts. [0] > I

The most complete plan for this was proposed by JPL's Slava Turyshev and team. It has been selected for Phase III of NASA Innovative Advanced Concepts. [0] > In 2020, Turyshev presented his idea of Direct Multi-pixel Imaging and Spectroscopy of an Exoplanet with a Solar Gravitational Lens Mission. The lens could reconstruct the exoplanet image with ~25 km-scale surface resolution in 6 months of integration time, enough to see surface features and signs of habitability. His proposal was selected for the Phase III of the NASA Innovative Advanced Concepts. Turyshev proposes to use realistic-sized solar sails (~16 vanes of 10^3 m^2) to achieve the needed high velocity at perihelion (~150 km/sec), reaching 547 AU in 17 years. > In 2023, a team of scientists led by Turychev proposed the Sundiver concept,[1] whereby a solar sail craft can serve as a modular platform for various instruments and missions, including rendezvous with other Sundivers for resupply, in a variety of different self-sustaining orbits reaching velocities of ~5-10 AU/yr. Here is an interview with him laying out the entire plan.[2] It is the most interesting interview that I have seen in years, possibly ever. [0] https://en.wikipedia.org/wiki/Slava_Turyshev#Work https://en.wikipedia.org/wiki/Slava_Turyshev#Work [1] https://www2.mpia-hd.mpg.de/~calj/sundiver.pdf https://www2.mpia-hd.mpg.de/~calj/sundiver.pdf [2] https://www.youtube.com/watch?v=lqzJewjZUkk https://www.youtube.com/watch?v=lqzJewjZUkk

deleted 2y ago
[deleted]
potamic 2y ago
A 6 month integration time is going to generate massive amounts of data. How do they intend to receive all this back from 500 AU away?
- tomtom1337 2y ago
  Well, one single long exposure would literally generate a regular sized image. Though I do guess they’ll be doing multiple exposures if only to avoid saturating their dynamic range. Does anyone know what a typical number of acquired frames is for a space telescope?
- andy_ppp 2y ago
  The computer onboard likely merges everything into a final image in space?
  - Cthulhu_ 2y ago
    Sure, it would discard a lot of data / noise, and would send a preview over first, but like with the Pluto probe, they do want to get as much data as possible, as an image is only a representation thereof.
  - defrost 2y ago
    Orbiting instruments typically transmit raw instruments data blocked into lines or segments that are are each surrounded by checksums. It might be compressed for transmission, but raw data (warts and all) is king .. once it's "processed" and raw data is discarded .. there's no recovering the raw. Years later raw data can be reprocessed with new algorithms, faster processes and combined with other sources to create "better" processed images. Onboard hardware errors (eg: the historic Hubble Telescope erros) can be "corrected" later on the ground with an elaborate backpropagated trandfer function that optimally "fixes" the error, etc. Data errors (spikes in cell values, glitches from cosmic rays, etc) can be combed out of the raw in post .. if smart people have access to the raw. Baking processing into on board instrument processing prior to transmission isn't a good procedure.
    - tlb 2y ago
      You could store all the data on the satellite, upload new code to process it differently, and download the resulting image. Then, the communications link just has to handle code (several MB up) and images (several MB down) instead of petabytes of data. The launch mass of a petabyte of SSD is under 10 kg. I don't know if it would survive 17 years of space radiation though.
      - defrost 2y ago
        Well, you could. I don't think I'd do that. Ignoring the failure modes of a petabyte of SSD spending decades in deep space, what kinds of things are difficult and|or impossible if you were to > store all the data on the satellite, upload new code to process it differently, and download the resulting image ?
protomolecule 2y ago
[flagged]
- rendall 2y ago
  Stop. For whatever reason, he has people call him Slava and does not correct them when they do so.
  - protomolecule 2y ago
    >For whatever reason The reason is that you won't bother to pronounce Vyacheslav so Russians have to use a short version of their name.
    - gambiting 2y ago
      No, they don't have to - they are chosing to. To pretend otherwise is to say they don't have agency in this, which they do.
      - protomolecule 2y ago
        Even if somebody puts a gun to your head and orders you to change your name, you'd still have a choice and it would be your decision what to do. That's not much of an argument though.
        gambiting 2y ago
        No one put a gun to his head though. Discomfort of English speakers isn't enough reason to not use your real name if that's your preference. Again, speaking from experience.
        PaulHoule 2y ago
        Many Chinese (speaking) students in the US pick an English language name like “William” or “Wendy” because they know people they meet will struggle with a name which could be several short words with unfamiliar vowels and consonants and tone that matters.
IncreasePosts 2y ago
Sadly ,the last reference I see to this project is from 2022, from his own CV on his JPL profile page. What happens after stage 3 with NIAC? Is there even a stage 4, or does it need to get selected by some committee or something?
- schlauerfox 2y ago
  There was a massive 8% JPL layoff earlier in the year with a vauge 'uncertain upcoming budget' justification, perhaps affected a lot of plans. I don't have any inside info though.
izend 2y ago
NASA and SpaceX should start architecting a Deep Space Network 2.0 relying on more space based relays so that we do need to rely on giant ground based antennae. Put a relay at the Lagrange point.
- Retric 2y ago
  The economics really don’t work out. Stick a relay at the midpoint between earth / Voyager 1 so it gets a signal that’s 4x as strong. Unfortunately that’s still really weak so it needs a huge dish, and orbital mechanics means it can’s stay in that position. We’re better off sending out probes that send stronger signals and just build huge ground based systems. At least until space based manufacturing becomes practical. PS: Where relays make sense is for probes on the surface of a planet etc communicating with something in orbit which then sends signals to earth.
mapt 2y ago
Introducing BLEO rendezvous elements for "resupply" into a mission with such wild dV scope and no landers, imposes some extreme constraints. I don't understand why you would do that unless solar sails as he understands them are extremely scale-dependent (like atmospheric flight is scale-dependent). I learned this doing engineering trades on the Aldrin cycler idea; Ultimately it doesn't add much to a mission because getting there and getting back into the transfer sacrifices more than you could really hope to gain. You're likely better off just launching what you need attached to everything else at the Earth escape burn.
- Valgrim 2y ago
  I'm curious about the Aldrin Cycler analysis. Isn't the whole point of the "castle" to house travelers and life support system in a larger habitable space during the long travel, independently of the cargo required for mars that's carried on a different, cheaper trajectory?
  - mapt 2y ago
    It's been a few years, and my memory isn't perfect, but... Life support for a manned Mars missions runs maybe ten tons per person on the low end. That's mostly in shelf-stable packaged food; I used 6 tons in my estimate. Metabolizing food generates excess CO2 + H2O; elaborate ECLSS systems can crack this for extra oxygen and filter the water for further consumption and sanitation. This food dominates mission payload mass. It's heavier than the rest of the habitat put together. You have to put it to good use - line the interior of the hull with it and it serves as radiation shielding for the journey. You could try getting the CO2 + H2O back into hydrocarbon-lox fuel if you like, but that's going to make a fragile critical path for getting home. The base hardware for Mars and the people for Mars are going on basically the same Hohmann transfer, and they're using it because it's the cheapest way. There are faster ways involving the help of Venus' gravity well, but they're only SLIGHTLY faster, they burn a lot more fuel, and more importantly they only occur briefly every few years. A more rapid direct transfer is possible at the cost of enormous amounts of fuel, but the purpose of that transfer is a 'flags and footprints' mission where you save about a third of your 3-year mission time at the cost of reducing your exploration and ISRU time window from a year to weeks. "Opposition class mission" vs "Conjunction class mission".

deleted 2y ago

[deleted]

potamic 2y ago

A 6 month integration time is going to generate massive amounts of data. How do they intend to receive all this back from 500 AU away?

tomtom1337 2y ago
Well, one single long exposure would literally generate a regular sized image. Though I do guess they’ll be doing multiple exposures if only to avoid saturating their dynamic range. Does anyone know what a typical number of acquired frames is for a space telescope?
andy_ppp 2y ago
The computer onboard likely merges everything into a final image in space?
- Cthulhu_ 2y ago
  Sure, it would discard a lot of data / noise, and would send a preview over first, but like with the Pluto probe, they do want to get as much data as possible, as an image is only a representation thereof.
- defrost 2y ago
  Orbiting instruments typically transmit raw instruments data blocked into lines or segments that are are each surrounded by checksums. It might be compressed for transmission, but raw data (warts and all) is king .. once it's "processed" and raw data is discarded .. there's no recovering the raw. Years later raw data can be reprocessed with new algorithms, faster processes and combined with other sources to create "better" processed images. Onboard hardware errors (eg: the historic Hubble Telescope erros) can be "corrected" later on the ground with an elaborate backpropagated trandfer function that optimally "fixes" the error, etc. Data errors (spikes in cell values, glitches from cosmic rays, etc) can be combed out of the raw in post .. if smart people have access to the raw. Baking processing into on board instrument processing prior to transmission isn't a good procedure.
  - tlb 2y ago
    You could store all the data on the satellite, upload new code to process it differently, and download the resulting image. Then, the communications link just has to handle code (several MB up) and images (several MB down) instead of petabytes of data. The launch mass of a petabyte of SSD is under 10 kg. I don't know if it would survive 17 years of space radiation though.
    - defrost 2y ago
      Well, you could. I don't think I'd do that. Ignoring the failure modes of a petabyte of SSD spending decades in deep space, what kinds of things are difficult and|or impossible if you were to > store all the data on the satellite, upload new code to process it differently, and download the resulting image ?

protomolecule 2y ago

[flagged]

rendall 2y ago
Stop. For whatever reason, he has people call him Slava and does not correct them when they do so.
- protomolecule 2y ago
  >For whatever reason The reason is that you won't bother to pronounce Vyacheslav so Russians have to use a short version of their name.
  - gambiting 2y ago
    No, they don't have to - they are chosing to. To pretend otherwise is to say they don't have agency in this, which they do.
    - protomolecule 2y ago
      Even if somebody puts a gun to your head and orders you to change your name, you'd still have a choice and it would be your decision what to do. That's not much of an argument though.
      - gambiting 2y ago
        No one put a gun to his head though. Discomfort of English speakers isn't enough reason to not use your real name if that's your preference. Again, speaking from experience.
        PaulHoule 2y ago
        Many Chinese (speaking) students in the US pick an English language name like “William” or “Wendy” because they know people they meet will struggle with a name which could be several short words with unfamiliar vowels and consonants and tone that matters.

IncreasePosts 2y ago

Sadly ,the last reference I see to this project is from 2022, from his own CV on his JPL profile page. What happens after stage 3 with NIAC? Is there even a stage 4, or does it need to get selected by some committee or something?

schlauerfox 2y ago
There was a massive 8% JPL layoff earlier in the year with a vauge 'uncertain upcoming budget' justification, perhaps affected a lot of plans. I don't have any inside info though.

izend 2y ago

NASA and SpaceX should start architecting a Deep Space Network 2.0 relying on more space based relays so that we do need to rely on giant ground based antennae. Put a relay at the Lagrange point.

Retric 2y ago
The economics really don’t work out. Stick a relay at the midpoint between earth / Voyager 1 so it gets a signal that’s 4x as strong. Unfortunately that’s still really weak so it needs a huge dish, and orbital mechanics means it can’s stay in that position. We’re better off sending out probes that send stronger signals and just build huge ground based systems. At least until space based manufacturing becomes practical. PS: Where relays make sense is for probes on the surface of a planet etc communicating with something in orbit which then sends signals to earth.

mapt 2y ago

Introducing BLEO rendezvous elements for "resupply" into a mission with such wild dV scope and no landers, imposes some extreme constraints. I don't understand why you would do that unless solar sails as he understands them are extremely scale-dependent (like atmospheric flight is scale-dependent). I learned this doing engineering trades on the Aldrin cycler idea; Ultimately it doesn't add much to a mission because getting there and getting back into the transfer sacrifices more than you could really hope to gain. You're likely better off just launching what you need attached to everything else at the Earth escape burn.

Valgrim 2y ago
I'm curious about the Aldrin Cycler analysis. Isn't the whole point of the "castle" to house travelers and life support system in a larger habitable space during the long travel, independently of the cargo required for mars that's carried on a different, cheaper trajectory?
- mapt 2y ago
  It's been a few years, and my memory isn't perfect, but... Life support for a manned Mars missions runs maybe ten tons per person on the low end. That's mostly in shelf-stable packaged food; I used 6 tons in my estimate. Metabolizing food generates excess CO2 + H2O; elaborate ECLSS systems can crack this for extra oxygen and filter the water for further consumption and sanitation. This food dominates mission payload mass. It's heavier than the rest of the habitat put together. You have to put it to good use - line the interior of the hull with it and it serves as radiation shielding for the journey. You could try getting the CO2 + H2O back into hydrocarbon-lox fuel if you like, but that's going to make a fragile critical path for getting home. The base hardware for Mars and the people for Mars are going on basically the same Hohmann transfer, and they're using it because it's the cheapest way. There are faster ways involving the help of Venus' gravity well, but they're only SLIGHTLY faster, they burn a lot more fuel, and more importantly they only occur briefly every few years. A more rapid direct transfer is possible at the cost of enormous amounts of fuel, but the purpose of that transfer is a 'flags and footprints' mission where you save about a third of your 3-year mission time at the cost of reducing your exploration and ISRU time window from a year to weeks. "Opposition class mission" vs "Conjunction class mission".