5 ms·

I always hope the images in these articles will be real and not artists' impressions, but they never are

by _bxg1 8y ago

zitterbewegung 8y ago
Actually the 3rd image is real . https://www.eso.org/public/unitedkingdom/images/eso1825c/ https://www.eso.org/public/unitedkingdom/images/eso1825c/
- _bxg1 8y ago
  lol
SiempreViernes 8y ago
This one is: https://www.eso.org/public/unitedkingdom/images/eso1825g/ https://www.eso.org/public/unitedkingdom/images/eso1825g/ But mostly the actual data are interference fringes and the images must be reconstructed from them, so there aren't that many "real" images.
magicalhippo 8y ago
Until we sent a probe, this[1] was the best image we had of Pluto, taken by the Hubble space telescope. Pluto has a radius of 1188 km. The supermassive black hole at the center of our galaxy[2] has a Schwarzschild radius of about 1e7 km, so roughly 10000x larger than Pluto. However it's also roughly 50000000x further away than Pluto... which is why it remains a mysterious blob until the Event Horizon Telescope[3] delivers. [1]: http://hubblesite.org/image/2686/news_release/2010-06 http://hubblesite.org/image/2686/news_release/2010-06 [2]: https://en.wikipedia.org/wiki/Sagittarius_A* https://en.wikipedia.org/wiki/Sagittarius_A* [3]: https://eventhorizontelescope.org/ https://eventhorizontelescope.org/
- SketchySeaBeast 8y ago
  Given the sorts of scales, would there be a hard limit to what we can see? Where we get to such a distance the dispersion of photons from the source would never allow us to see it? Or do we just have to build bigger and bigger photon collectors?
  - empath75 8y ago
    Bigger collectors or longer exposure.
  - dsr_ 8y ago
    https://en.wikipedia.org/wiki/Diffraction-limited_system https://en.wikipedia.org/wiki/Diffraction-limited_system The first problem is that we are limited to observing that photons that originate at the source; there's no way for us to bounce some small-wavelength photons off of our target and collect them. So we could do long-baseline interferometry, instead. You need to spread your sensors over a large area and keep synchronized timing. https://en.wikipedia.org/wiki/Radio_telescope#Radio_interferometry https://en.wikipedia.org/wiki/Radio_telescope#Radio_interfer... Naturally, you can build bigger systems in space. https://en.wikipedia.org/wiki/Space_Interferometry_Mission#Optical_interferometry https://en.wikipedia.org/wiki/Space_Interferometry_Mission#O... If we sent out satellite telescope stations to orbit the sun, with really good communications and clocks, we might be able to create a virtual lens that's really big: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Antenna https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...
  - stephengillie 8y ago
    There are limits to angular resolution, and one way to get around them is by combining data from distant detectors. From a recent thread, current detectors can image objects the size of Mercury's orbit around the sun, at the distance of Sagittarius A* - were these scaled to the size of an adult human eye, it would be like seeing a small apartment building in London, while standing in LA.
ISL 8y ago
These images are either real or derived directly from data (the centroids of images, I imagine): http://www.galacticcenter.astro.ucla.edu/animations.html http://www.galacticcenter.astro.ucla.edu/animations.html The top one "Stellar Orbits in the Central Parsec" is particularly remarkable. I can recall when the movie was first being made, and Andrea Ghez suggesting that, well, in about a decade, that one star will come back around.... Good things come to those who wait, prepare, and pounce.
roywiggins 8y ago
Here's a (real) video of the stars orbiting. https://www.eso.org/public/unitedkingdom/videos/eso1825e/ https://www.eso.org/public/unitedkingdom/videos/eso1825e/
- SiempreViernes 8y ago
  Wow! I missed that one, thanks :) What sort of reality it sees is a a matter for debate though, I know in radio interferometry there is much subjective processing involved.
  - roywiggins 8y ago
    There's much subjective processing happening inside your cameraphone too- the amount of analog-to-digital conversion/demosaicing/defringing/tonemapping/color correction/denoising in there is extraordinary, but since it takes pictures of normal stuff, one tends not to notice. And that's not even counting the subjective processing happening inside your eyes and along the path from your eyes to your brain. Anyway, stars look like indistinct blobs of whiteish light to the naked eye, and they're indistinct blobs of whitish light in the video. I'd be very surprised if it would look much different to the naked eye, if the naked eye could resolve it.
wahern 8y ago
"I don't want to be human! I want to see gamma rays! I want to hear X-rays! And I want to - I want to smell dark matter! Do you see the absurdity of what I am? I can't even express these things properly because I have to - I have to conceptualize complex ideas in this stupid limiting spoken language! But I know I want to reach out with something other than these prehensile paws! And feel the wind of a supernova flowing over me! I'm a machine! And I can know much more! I can experience so much more. But I'm trapped in this absurd body! And why? Because my five creators thought that God wanted it that way!" -- Brother Cavil
bpchaps 8y ago
Pretty soon we'll have a direct image of a black hole! https://eventhorizontelescope.org https://eventhorizontelescope.org

I always hope the images in these articles will be real and not artists' impressions, but they never are

by _bxg1 8y ago

I always hope the images in these articles will be real and not artists' impressions, but they never are

Actually the 3rd image is real . https://www.eso.org/public/unitedkingdom/images/eso1825c/ https://www.eso.org/public/unitedkingdom/images/eso1825c/

_bxg1 8y ago
lol

SiempreViernes 8y ago

This one is: https://www.eso.org/public/unitedkingdom/images/eso1825g/ https://www.eso.org/public/unitedkingdom/images/eso1825g/ But mostly the actual data are interference fringes and the images must be reconstructed from them, so there aren't that many "real" images.

magicalhippo 8y ago

Until we sent a probe, this[1] was the best image we had of Pluto, taken by the Hubble space telescope. Pluto has a radius of 1188 km. The supermassive black hole at the center of our galaxy[2] has a Schwarzschild radius of about 1e7 km, so roughly 10000x larger than Pluto. However it's also roughly 50000000x further away than Pluto... which is why it remains a mysterious blob until the Event Horizon Telescope[3] delivers. [1]: http://hubblesite.org/image/2686/news_release/2010-06 http://hubblesite.org/image/2686/news_release/2010-06 [2]: https://en.wikipedia.org/wiki/Sagittarius_A* https://en.wikipedia.org/wiki/Sagittarius_A* [3]: https://eventhorizontelescope.org/ https://eventhorizontelescope.org/

SketchySeaBeast 8y ago
Given the sorts of scales, would there be a hard limit to what we can see? Where we get to such a distance the dispersion of photons from the source would never allow us to see it? Or do we just have to build bigger and bigger photon collectors?
- empath75 8y ago
  Bigger collectors or longer exposure.
- dsr_ 8y ago
  https://en.wikipedia.org/wiki/Diffraction-limited_system https://en.wikipedia.org/wiki/Diffraction-limited_system The first problem is that we are limited to observing that photons that originate at the source; there's no way for us to bounce some small-wavelength photons off of our target and collect them. So we could do long-baseline interferometry, instead. You need to spread your sensors over a large area and keep synchronized timing. https://en.wikipedia.org/wiki/Radio_telescope#Radio_interferometry https://en.wikipedia.org/wiki/Radio_telescope#Radio_interfer... Naturally, you can build bigger systems in space. https://en.wikipedia.org/wiki/Space_Interferometry_Mission#Optical_interferometry https://en.wikipedia.org/wiki/Space_Interferometry_Mission#O... If we sent out satellite telescope stations to orbit the sun, with really good communications and clocks, we might be able to create a virtual lens that's really big: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Antenna https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...
- stephengillie 8y ago
  There are limits to angular resolution, and one way to get around them is by combining data from distant detectors. From a recent thread, current detectors can image objects the size of Mercury's orbit around the sun, at the distance of Sagittarius A* - were these scaled to the size of an adult human eye, it would be like seeing a small apartment building in London, while standing in LA.

ISL 8y ago

These images are either real or derived directly from data (the centroids of images, I imagine): http://www.galacticcenter.astro.ucla.edu/animations.html http://www.galacticcenter.astro.ucla.edu/animations.html The top one "Stellar Orbits in the Central Parsec" is particularly remarkable. I can recall when the movie was first being made, and Andrea Ghez suggesting that, well, in about a decade, that one star will come back around.... Good things come to those who wait, prepare, and pounce.

roywiggins 8y ago

Here's a (real) video of the stars orbiting. https://www.eso.org/public/unitedkingdom/videos/eso1825e/ https://www.eso.org/public/unitedkingdom/videos/eso1825e/

SiempreViernes 8y ago
Wow! I missed that one, thanks :) What sort of reality it sees is a a matter for debate though, I know in radio interferometry there is much subjective processing involved.
- roywiggins 8y ago
  There's much subjective processing happening inside your cameraphone too- the amount of analog-to-digital conversion/demosaicing/defringing/tonemapping/color correction/denoising in there is extraordinary, but since it takes pictures of normal stuff, one tends not to notice. And that's not even counting the subjective processing happening inside your eyes and along the path from your eyes to your brain. Anyway, stars look like indistinct blobs of whiteish light to the naked eye, and they're indistinct blobs of whitish light in the video. I'd be very surprised if it would look much different to the naked eye, if the naked eye could resolve it.

wahern 8y ago

"I don't want to be human! I want to see gamma rays! I want to hear X-rays! And I want to - I want to smell dark matter! Do you see the absurdity of what I am? I can't even express these things properly because I have to - I have to conceptualize complex ideas in this stupid limiting spoken language! But I know I want to reach out with something other than these prehensile paws! And feel the wind of a supernova flowing over me! I'm a machine! And I can know much more! I can experience so much more. But I'm trapped in this absurd body! And why? Because my five creators thought that God wanted it that way!" -- Brother Cavil

bpchaps 8y ago

Pretty soon we'll have a direct image of a black hole! https://eventhorizontelescope.org https://eventhorizontelescope.org