Questions tagged [event-horizon-telescope]
Questions about the Event Horizon Telescope, or EHT.
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Would the Event Horizon Telescope be able to produce a superior image of Betelgeuse?
Current images of Betelgeuse are already amazing, but I was wondering if the EHT could be able to make a significantly better image, given that Betelgeuse is pretty big and pretty bright?
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From whence is the Event Horizon Telescope black hole data available for amateur reconstruction?
Ralf Vandebergh's tweet shows his own reconstruction of an image of the accretion disk around a black hole, generated presumably from Event Horizon Telescope data.
I'm assuming that the data came ...
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Could images of (very) nearby targets be recovered from Event Horizon Telescope data?
Reading this question I was struck by the fact that the "pointing" of an interferometer is effectively done in the correlator, at least within the common field of view of all the telescopes, which is ...
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Would Hubble Space Telescope improve black hole image observed by EHT if it joined array of telesopes?
My question is related to black hole image released in April. As far as I understand idea of EHT, it joins observations from multiple locations to work like one telescope with radius that is equal to ...
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If a black hole does not emit light, how can one take a picture of the black hole itself?
There's some discussion that the image composed by the Event Horizons Telescope is really just an accretion disk. To "take an image" of something, you need the light reflecting off of the surface of ...
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Do the "schwarzschild metric" or the "isotropic metric" fit the Event Horizon telescope data on Messier 87 better?
The "Schwarzschild solution" in "Schwarzschild metric" looks like:
$$\text -c^2d\tau^2=-\left(1-\frac{2GM}{rc^2}\right)c^2dt^2+\left(1-\frac{2GM}{rc^2}\right)^{-1}dr^2+r^2(d\theta^2+\sin^2\theta\,d\...
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What is the actual resolution of Event Horizon Telescope?
I am quite impressed with the recently published image of M87* black hole. It appears that this image achieves spatial resolution well above and beyond what was available until today. But how high ...
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What do the lines in this Event Horizon Telescope and Global mm-VLBI Array infographic represent?
In the following EHT and GMVA diagram, what do the yellow and blue lines represent? I don't think they're physical communication lines (that would be unfeasible). Do they depict anything specific?
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What else could the Event Horizon Telescope Observe?
The Event Horizon Telescope was made possible in order to observe the details of supermassive black holes. This took a huge amount of work installing extra telescopes and developing the hardware and ...
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Is this the best non-radio image of whatever's at the center of M87? How was it taken?
The BBC News article First ever black hole image released shows the instantly-iconic radio image of the (almost certainly) supermassive black hole at the center of the M87 galaxy, just released by the ...
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Why are there uneven bright areas in this photo of black hole?
In the recently released photo of a black hole shown above, which was created by using data from EHT, why is the lower region brighter than the one above? Is it because of the rotation of the ...
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Why not take a picture of a closer black hole?
There are closer galaxies than Messier 87 for sure, even ours! It sparked my curiosity that they went with one 53 million light years away. Is there a reason for this?
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What is the orientation of the M87 black hole image relative to the jet?
On the image of the M87 black hole released today by the Event Horizon Telescope team, which direction points towards the jet? Is it on the brighter side of the ring?
To resolve ambiguity, I'm ...
user24157
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What does it mean when there are two plus-or-minus signs for a measurement?
As far as I know, the plus-or-minus sign is used to indicate the statistical margin of error of a measurement. But what does it mean when there are two plus-or-minus signs in the same measurement?
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Why didn't the Event Horizon Telescope team mention Sagittarius A*?
At the press conference this morning, the Event Horizon Telescope team didn't say much about Sagittarius A*, which was the target many of us have been waiting for.
Is there any explanation anywhere ...
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