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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Convert from Jy/beam km/s to W/m$^2$
I need to compare some ALMA observations of a protoplanetary disk to disk-integrated fluxes obtained from a model.
The ALMA observations are upper limits of non-detected spectral lines, where the RMS ...
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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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How did Michelson measure the diameters of jupiter's moons using optical interferometry?
In Betelgeuse: How its Diameter was measured (Chant, C. A., Journal of the Royal Astronomical Society of Canada, Vol. 15, p.133, Bibliographic Code: 1921JRASC..15..133C) the author says:
The paper in ...
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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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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 ...
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Mega Telescope using gravitational lensing and interferometry
I have been thinking about this crazy telescope idea, but I am not smart enough to understand if it's technically possible. I understand from an engineering and practical point of view it's a long way ...
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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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Angular diameter and length of baseline
How did they determine the angular diameter, please? How to predict the baseline length with the first lobe?
Thank you.
https://www.chara.gsu.edu/public/basics-of-interferometry
If they are ...
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Can any radio telescope be hooked up with the Very Long Baseline Array, or other interferometers?
The Very Long Baseline Array uses both Arecibo and Spectr-R, the world's largest space telescope with 10 m diameter at Lunar distance, as well as many other antennas. Are there any particular ...
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Can the expansion of spacetime be directly measured with laser interferometry (like GW can)
LIGO has a mind boggling sensitivity. What would it take to directly measure the expansion of spacetime, along the laser beam? I suppose it could be done at interplanetary scale.
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Maximum number of pixels across a synthesized beam in an ALMA image?
I have some ALMA data, from which I have created images using the TCLEAN task in CASA.
I understand that with this type of data, it is necessary to have at least 2 pixels across the FWHM of the ...
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How does speckle imaging fit in to 21st century high resolution imaging from ground based observatories?
Phys.org's Astronomers uncover evidence that there could be many more Earth-sized planets than previously thought references Speckle Observations of TESS Exoplanet Host Stars. II. Stellar Companions ...
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How can I determine the location of an object for one observer given the location for another?
I know an object exists at the location of the beam-pointing-center of a radio telescope. I know the elevation/azimuth of the beam pointing center, as well as it’s “location” in galactic coordinates. ...
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Calculating angular diameter amplitude from angular diameter variations of Cepheid variable
I'm a high school student but have as much interests in Cepheid variable as the professionalists. I'm trying to derive independent distances to Cepheid with the Baade-Wesselink method.
I got the ...
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W in the brightness distribution
What is W in the brightness (intensity) distribution, please?
Alpha is the position of the star; lambda, the wavelength; t, the time; P, the polarization.
Thank you
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