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I've always wondered how that works. I'm all for full bore public spending on space but sometimes when you read the list of the research goals for NASA/EU spend

by dmix 4y ago

I've always wondered how that works. I'm all for full bore public spending on space but sometimes when you read the list of the research goals for NASA/EU spending hundreds of millions on getting to Jupiter (for ex) I often wonder "that's it"? But then I remind myself I don't know anything about this stuff compared to the people doing it as their job and assume the scientists/admins have some set of priorities which are essential in the process for some bigger important stuff. My biggest question is why they aren't putting tons of pressure on getting a telescope that can do gravitational lensing to see as far into space as possible ASAP. But again I'm probably just speaking out of turn not being familiar with the wider industry/culture/economics.

shagie 4y ago
> My biggest question is why they aren't putting tons of pressure on getting a telescope that can do gravitational lensing to see as far into space as possible ASAP. But again I'm probably just speaking out of turn not being familiar with the wider industry/culture/economics. You are likely interested in the FOCAL project. https://en.wikipedia.org/wiki/FOCAL_(spacecraft) https://en.wikipedia.org/wiki/FOCAL_(spacecraft) > FOCAL (an acronym for Fast Outgoing Cyclopean Astronomical Lens) is a proposed space telescope that would use the Sun as a gravity lens. The gravitational lens effect was first derived by Albert Einstein, and the concept of a mission to the solar gravitational lens was first suggested by professor Von Eshleman, and analyzed further by Italian astronomer Claudio Maccone and others. > In order to use the Sun as a gravity lens, it would be necessary to send the telescope to a minimum distance of 550 astronomical units away from the Sun, enabling very high signal amplifications: for example, at the 203 GHz wavelength, amplification of 1.3 x 10^15. Maccone suggests that this should be enough to obtain detailed images of the surfaces of extrasolar planets. --- That 550 AU... for comparison, Voyager 1 is currently at about 159 AU and moving at 3.6 AU/year. New Horizons is "only" 55.6 AU and going at 2.9 AU/year. But its an interesting project.
- Mtinie 4y ago
  Was the Voyager series designed and optimized to get outside the heliosphere and into interstellar space as fast as possible? I just don’t have context to know whether covering 159 AU over ~45 years is exceptionally fast (for human-made objects) of if 550 AU could be reasonably reached in a far shorter timeframe if that was the primary goal.
  - SoftTalker 4y ago
    No. The original Voyager mission was designed to explore Jupiter and Saturn. After launch, they decided to fly by Uranus and Neptune as well. There was never an expectation that the spacecraft would survive and reach, let alone still be useful in interstellar space.
  - Kye 4y ago
    159 AU is about a day's travel for light (~22 light hours). Something designed to get that far quickly would be a tiny payload with a lot of fuel and a weak but efficient engine behind it to accelerate constantly for a very long time. Voyager benefited from a rare alignment of planets that let them send it on a long, wandering journey around gravity wells, so it's very slow compared to what's possible with existing technology.
    - shagie 4y ago
      If you watch DSN... https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html (and as I type this, its got a downlink from VGR1) you can occasionally see communication links to Voyager (and others). And since its there now... SPACECRAFT NAME Voyager 1 RANGE 23.80 billion km ROUND-TRIP LIGHT TIME 1.84 days SOURCE VOYAGER 1 FREQUENCY BAND X DATA RATE 160.0 b/sec POWER RECEIVED -160 dBm (1.0 x 10-22 kW)
      - Kye 4y ago
        Was Google wrong (159 AU in light hours), or was the 159 AU I pulled from their comment off? Google answered with a conversion box, so I assumed it had a human checking the formulas and wasn't from their notoriously unreliable auto-snippets.
        shagie 4y ago
        DSN is interested in the round trip time - they're both right. How long does it take to ACK the data that was sent? 1.84 days. How old is the data that was sent? 0.92 days (22 hours). Communication protocols at that distance are kind of interesting. Things like dropped data and delays can make it challenging. https://en.wikipedia.org/wiki/Interplanetary_Internet https://en.wikipedia.org/wiki/Interplanetary_Internet https://www.nasa.gov/directorates/heo/scan/engineering/technology/disruption_tolerant_networking_overview https://www.nasa.gov/directorates/heo/scan/engineering/techn... https://ipnsig.org/tag/deep-space-network/ https://ipnsig.org/tag/deep-space-network/ https://www.nytimes.com/1990/10/02/science/spacecraft-passes-a-critical-test.html?unlocked_article_code=hBBXhY68kw4onDAZ8jc8tjxF-ORQ3xyKQyIvfWBEmk1eUMyFXpFK26qBShUdhulioha7gfO7szqFVsg5uDOioXq8QSCCPMQB8xUCObxJiELfJziUUfrVTvzTQciT6WLP8t7bC_hL5McmXeH7tvH7Huqyj__Viv7DcO-IQljkErZrP2mhTXaUnVrlxLZOpZE0qRFxY__Eq7tCCoEdEcCRoTqwcLjDGuuv8xR2cWnNxBd-J2dpSYWsWZicLw1-1yh3aoV0bYWInS86FfmxWF1VhMbG83R_Ef5-uBDkRSe_XQOX46QTdCXpltygGm7ziGBZjvTeyP0JS0OYQtP6zseY3g5cqspn8xLOR9Xm&giftCopy=1_CurrentCopy&smid=url-share https://www.nytimes.com/1990/10/02/science/spacecraft-passes...
- dmix 4y ago
  > Even without using the Sun as the lens, FOCAL could perform various, otherwise impossible measurements: a separate telescope could be used to measure stellar distances by parallax, which would, using the baseline of 550 AU, measure the precise position of every star in the Milky Way,: 18 enabling various further scientific discoveries.: 18–22 It could also study the interstellar medium,: 22 the heliosphere,: 27 observe gravitational waves,: 25 check for the possible variation of the gravitational constant,: 25 observe the cosmic infrared background,: 26 characterise interplanetary dust within the Solar System,: 27–28 more precisely measure the mass of the Solar System: 26 and similar. Even more reasons to be an evangelist for this sort of project. Compared to settling Mars this seems infinitely more important unless you have some hyper skeptical view of human society. Seeing the surface of extrasolar planets should be the #1 goal easily IMO
  - prox 4y ago
    Wow your post got me all excited. When can we do this type of vibe!
  - krisoft 4y ago
    > Seeing the surface of extrasolar planets Planet. Singular. Not plural. The nature of gravitational lensing is that you would need to build and place a new telescope for every different direction you want to look. The relevant quote from the linked wikipedia page is: “FOCAL would be able to observe only objects that are right behind the Sun from its point of view, which means that for every observed object a new telescope would have to be made.” > Compared to settling Mars this seems infinitely more important unless you have some hyper skeptical view of human society. My “hyper skeptical” view of human society is that it is fragile. There are many possible catastrophes which could wipe all of us out, then there are many other possible situations which would not kill all of us but would shunt humanity forever. Settling Mars would make us more resilient in two major ways: The settlement on Mars is a physical off-site backup to human society. And the necessary R&D to achieve a self-sustaining Mars setlement would force us to develop and test for reliability under real world circumstances tech which we could use here on Earth to better survive many of those calamities. It is literally a ticket to raise the probability of the continued existence of humankind. On the other hand a picture of an exoplanet is a picture. An interesting one sure. If we would have it now it would be probably front page news. It would be a blurry pixelated disk with smears of colour. That would be all for 99% of humanity. For the select few they would study the image and analyse it and we would have follow on studies in a few years saying things like: “We are reasonably sure this area is a shallow sea, and we think this colour fluctuation is consistent with an algea bloom.” Iff(!) we got lucky and the exoplanet we aimed the telescope at is not a dead, dry rock. So increasing the chance of our survival vs a blury picture which will pose more question than it answers. How are these two goals in any way comparable? Let alone the second being more important?

by dmix 4y ago

shagie 4y ago

> My biggest question is why they aren't putting tons of pressure on getting a telescope that can do gravitational lensing to see as far into space as possible ASAP. But again I'm probably just speaking out of turn not being familiar with the wider industry/culture/economics. You are likely interested in the FOCAL project. https://en.wikipedia.org/wiki/FOCAL_(spacecraft) https://en.wikipedia.org/wiki/FOCAL_(spacecraft) > FOCAL (an acronym for Fast Outgoing Cyclopean Astronomical Lens) is a proposed space telescope that would use the Sun as a gravity lens. The gravitational lens effect was first derived by Albert Einstein, and the concept of a mission to the solar gravitational lens was first suggested by professor Von Eshleman, and analyzed further by Italian astronomer Claudio Maccone and others. > In order to use the Sun as a gravity lens, it would be necessary to send the telescope to a minimum distance of 550 astronomical units away from the Sun, enabling very high signal amplifications: for example, at the 203 GHz wavelength, amplification of 1.3 x 10^15. Maccone suggests that this should be enough to obtain detailed images of the surfaces of extrasolar planets. --- That 550 AU... for comparison, Voyager 1 is currently at about 159 AU and moving at 3.6 AU/year. New Horizons is "only" 55.6 AU and going at 2.9 AU/year. But its an interesting project.

Mtinie 4y ago
Was the Voyager series designed and optimized to get outside the heliosphere and into interstellar space as fast as possible? I just don’t have context to know whether covering 159 AU over ~45 years is exceptionally fast (for human-made objects) of if 550 AU could be reasonably reached in a far shorter timeframe if that was the primary goal.
- SoftTalker 4y ago
  No. The original Voyager mission was designed to explore Jupiter and Saturn. After launch, they decided to fly by Uranus and Neptune as well. There was never an expectation that the spacecraft would survive and reach, let alone still be useful in interstellar space.
- Kye 4y ago
  159 AU is about a day's travel for light (~22 light hours). Something designed to get that far quickly would be a tiny payload with a lot of fuel and a weak but efficient engine behind it to accelerate constantly for a very long time. Voyager benefited from a rare alignment of planets that let them send it on a long, wandering journey around gravity wells, so it's very slow compared to what's possible with existing technology.
  - shagie 4y ago
    If you watch DSN... https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html (and as I type this, its got a downlink from VGR1) you can occasionally see communication links to Voyager (and others). And since its there now... SPACECRAFT NAME Voyager 1 RANGE 23.80 billion km ROUND-TRIP LIGHT TIME 1.84 days SOURCE VOYAGER 1 FREQUENCY BAND X DATA RATE 160.0 b/sec POWER RECEIVED -160 dBm (1.0 x 10-22 kW)
    - Kye 4y ago
      Was Google wrong (159 AU in light hours), or was the 159 AU I pulled from their comment off? Google answered with a conversion box, so I assumed it had a human checking the formulas and wasn't from their notoriously unreliable auto-snippets.
      - shagie 4y ago
        DSN is interested in the round trip time - they're both right. How long does it take to ACK the data that was sent? 1.84 days. How old is the data that was sent? 0.92 days (22 hours). Communication protocols at that distance are kind of interesting. Things like dropped data and delays can make it challenging. https://en.wikipedia.org/wiki/Interplanetary_Internet https://en.wikipedia.org/wiki/Interplanetary_Internet https://www.nasa.gov/directorates/heo/scan/engineering/technology/disruption_tolerant_networking_overview https://www.nasa.gov/directorates/heo/scan/engineering/techn... https://ipnsig.org/tag/deep-space-network/ https://ipnsig.org/tag/deep-space-network/ https://www.nytimes.com/1990/10/02/science/spacecraft-passes-a-critical-test.html?unlocked_article_code=hBBXhY68kw4onDAZ8jc8tjxF-ORQ3xyKQyIvfWBEmk1eUMyFXpFK26qBShUdhulioha7gfO7szqFVsg5uDOioXq8QSCCPMQB8xUCObxJiELfJziUUfrVTvzTQciT6WLP8t7bC_hL5McmXeH7tvH7Huqyj__Viv7DcO-IQljkErZrP2mhTXaUnVrlxLZOpZE0qRFxY__Eq7tCCoEdEcCRoTqwcLjDGuuv8xR2cWnNxBd-J2dpSYWsWZicLw1-1yh3aoV0bYWInS86FfmxWF1VhMbG83R_Ef5-uBDkRSe_XQOX46QTdCXpltygGm7ziGBZjvTeyP0JS0OYQtP6zseY3g5cqspn8xLOR9Xm&giftCopy=1_CurrentCopy&smid=url-share https://www.nytimes.com/1990/10/02/science/spacecraft-passes...
dmix 4y ago
> Even without using the Sun as the lens, FOCAL could perform various, otherwise impossible measurements: a separate telescope could be used to measure stellar distances by parallax, which would, using the baseline of 550 AU, measure the precise position of every star in the Milky Way,: 18 enabling various further scientific discoveries.: 18–22 It could also study the interstellar medium,: 22 the heliosphere,: 27 observe gravitational waves,: 25 check for the possible variation of the gravitational constant,: 25 observe the cosmic infrared background,: 26 characterise interplanetary dust within the Solar System,: 27–28 more precisely measure the mass of the Solar System: 26 and similar. Even more reasons to be an evangelist for this sort of project. Compared to settling Mars this seems infinitely more important unless you have some hyper skeptical view of human society. Seeing the surface of extrasolar planets should be the #1 goal easily IMO
- prox 4y ago
  Wow your post got me all excited. When can we do this type of vibe!
- krisoft 4y ago
  > Seeing the surface of extrasolar planets Planet. Singular. Not plural. The nature of gravitational lensing is that you would need to build and place a new telescope for every different direction you want to look. The relevant quote from the linked wikipedia page is: “FOCAL would be able to observe only objects that are right behind the Sun from its point of view, which means that for every observed object a new telescope would have to be made.” > Compared to settling Mars this seems infinitely more important unless you have some hyper skeptical view of human society. My “hyper skeptical” view of human society is that it is fragile. There are many possible catastrophes which could wipe all of us out, then there are many other possible situations which would not kill all of us but would shunt humanity forever. Settling Mars would make us more resilient in two major ways: The settlement on Mars is a physical off-site backup to human society. And the necessary R&D to achieve a self-sustaining Mars setlement would force us to develop and test for reliability under real world circumstances tech which we could use here on Earth to better survive many of those calamities. It is literally a ticket to raise the probability of the continued existence of humankind. On the other hand a picture of an exoplanet is a picture. An interesting one sure. If we would have it now it would be probably front page news. It would be a blurry pixelated disk with smears of colour. That would be all for 99% of humanity. For the select few they would study the image and analyse it and we would have follow on studies in a few years saying things like: “We are reasonably sure this area is a shallow sea, and we think this colour fluctuation is consistent with an algea bloom.” Iff(!) we got lucky and the exoplanet we aimed the telescope at is not a dead, dry rock. So increasing the chance of our survival vs a blury picture which will pose more question than it answers. How are these two goals in any way comparable? Let alone the second being more important?