Questions tagged [interferometry]
Questions about astronomical observations which involve superimposing waves received by multiple, physically separated, receivers to obtain higher angular resolution.
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Does interstellar cloud obstruct or reduce the visibility?
We just pictured a medium distant black hole by combining data from various observatories around the world. That's when I wondered if interstellar cloud blocks the visibility at multiple position in ...
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How does the Large Binocular Telescope resolve so well in both orthogonal directions simultaneously?
The Forbes article Ask Ethan: How Does Very-Long-Baseline Interferometry Allow Us To Image A Black Hole? includes an example of optical interferometry from the Large Binocular Telescope, shown below.
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Why not us interferometry to take a picture of Pluto?
Interferometry is among the best ways (if not, the best way!) to have an image of a very distant object.
Recently a picture of the black hole at the center of M87 was released. It is the result of ...
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What are the challenges for the building and data analysis of the CHIME telescope?
The Canadian Hydrogen Intensity Mapping Experiment (CHIME) has discovered the second repeated fast radio burst recently. However, its structure is simple apparently. I wonder why we did not build a ...
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Estimate the number of pixels required to map the full primary beam of a Radio Telescope station
I am practising some exam questions for a radio interferometry exam, and I am struggling with this question:
The physical size of a single LOFAR station, operating at 150MHz is about 50m.
Estimate ...
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Can weak gravitational lensing or microlensing-induced wavefront distortion limit resolution of absurdly large aperture telescopes?
This is a theoretical question.
This answer to the question If we had the right technology could we see a distant star in detail? (presumably space-based) primarily addresses the scaling of ...
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Is Optical VLBI theoretically feasible? If not why not?
There are plenty of optical interferometers in use with baselines of up to maybe 1km. As far as I can find out, they all work by directly collecting the light at all the telescopes, using mirrors to ...
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Are they really sure this isn't an Airy disk? How was that ruled out?
How do they know that this is a spherical shell of gas, and not just something like an Airy pattern-like artifact produced by the VLT's large interferometric aperture?
Image from: https://www.eso.org/...
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Could the E.H.T. produce an image of the human artifacts on the moon?
Two days ago the New York Times featured the Event Horizon Telescope (E.H.T.), a huge virtual radio telescope emerging from combining data from several dishes scattered around the world. While the E.H....
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Converting Jy/beam to Jy?
Maybe its a dumb question, but to convert Jy/beam to Jy, I just have to multiply it by the beam size in sr right?
Being $\Omega$ the beam size:
$\Omega = \frac{\pi \theta_{maj} ~~ \theta_{min}}{4 \...
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What are the raisons d'être for the Large Binocular Telescope "binocularity"?
edit: The short form of the question is Why are there TWO telescopes?? A longer version follows.
The Large Binocular Telescope (and LBT blog as source of images below) has two 8.4 meter diameter ...
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What is a "limited array"?
I'm reading about the history and making of ESO's Very Large Telescope and I've found this article that says the scientific community had a choice between three suggestions: a one-piece 16m-telescope, ...
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Can two detectors for gravitational waves be combined into a very long baseline interferometer?
While detectors for gravitational waves are interferometers themselves, the question here is about an increase in resolution resulting from two or more detectors far away from each other.
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How are people converting intensities in Janskys to Kelvin?
I'm reading some ALMA proposals and I am often seeing a conversion from Jy to Kelvin when, for example, people quote noise levels or source flux.
For example on their sensitivity calculator
(https://...
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Why don't we use amateur astronomers' telescopes to create a huge interferometer?
Some telescopes in space have been proposed to function as an interferometer.
Being placed several hundreds or thousands of kilometers apart they could actual image exoplanets directly. To my ...
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