Questions tagged [event-horizon-telescope]

Questions about the Event Horizon Telescope, or EHT.

Filter by
Sorted by
Tagged with
6
votes
0answers
67 views

Is there work underway to push the long baseline capabilities of the Event Horizon Telescope to sub-millimeter wavelengths?

The Max Planck Institute for Radio Astronomy's press release Something is Lurking in the Heart of Quasar 3C 279; First Event Horizon Telescope Images of a Black-Hole Powered Jet shows a stunning ...
0
votes
1answer
109 views

Why don't we build an interferometer between Earth and the Moon?

The Event Horizon Telescope (EHT) does interferometry from an array of telescopes spread all across Earth. The data is locally stored on a hard drive and shipped to a central location, so the ...
4
votes
1answer
85 views

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?
1
vote
1answer
92 views

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 ...
2
votes
1answer
50 views

Could images of (very) nearby targets be recovered from the EHT 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 ...
4
votes
1answer
982 views

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 ...
2
votes
1answer
181 views

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\...
3
votes
1answer
186 views

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 ...
1
vote
1answer
47 views

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? ...
11
votes
3answers
262 views

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 ...
3
votes
1answer
230 views

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 ...
38
votes
3answers
7k views

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 ...
63
votes
5answers
13k views

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?
3
votes
1answer
486 views

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 ...
1
vote
1answer
132 views

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? ...
26
votes
2answers
8k views

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 ...
5
votes
3answers
249 views

How can the Event Horizon Telescope image Sgr A* when it's not visible from all sites at one time?

I went to https://eventhorizontelescope.org/array and read about the ten sites listed as part of the EHT, I have a mashed-up screen shot of them below. I made a little script also shown below with ...
6
votes
2answers
151 views

Is there any update on the Availability of Event Horizon Telescope Images?

There has been no news on the obvious public channels from the EHT project since last (Northern) summer. Does anyone have more information on when any results from the April 2017 run might be released?...