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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Multi-messenger astronomy: what is the potential of simultaneous detection of gravitational waves and neutrinos from a supernova?
Thanks to the efforts of the aLIGO team, gravitational wave astronomy is a reality. At the same time, neutrino detectors like Hyperkamiokande are becoming much more sensitive.
My question is: what ...
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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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Why hasn't VLBI been used to try and image giant exoplanets?
A Jupiter-sized object at 10 pc subtends an angle of 0.0001 arcseconds (100 micro-arcsec) at the Earth. The Event Horizon Telescope interferometry network is capable of a (demonstrated) angular ...
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Can the Hubble constant be measured directly?
By my calculations, the expansion of the universe should cause LIGO’s interferometers to alternate between constructive interference and destructive interference every couple days. Is this a practical ...
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Was GRAVITY built to look at one star?
GRAVITY (shown below) is a interferometric combiner of near infrared light from four very large telescopes called The Very Large Telescope in order to make careful astrometric measurements near the ...
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What makes small interferometers useful? Like NIRISS on JWST
NIRISS is an instrument on the James Webb Space Telescope. It has a "non-redundant aperture mask" which obviously covers most of the area of the sensor. It seems to be advantageous for high contrast ...
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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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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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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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LIGO: How can laser interferometry (wavelength >$10^{-7}$m) detect length changes of arms <$10^{-18}$ m?
I'm trying to understand the sensitivity of the LIGO interferometer. I've been reading around lots of discussion of how they manage noise cancellation between the two detectors, achieving a very pure ...
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What could a cloud of mini radio dishes see?
Suppose an astronomer gave a 1 m radio dish to 500 people scattered over the face of the Earth and connected them to the internet. The people are directed to set their radio antennae up in their ...
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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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rms noise, confusion and dynamic range in radio images
I have been trying to understand imaging in radio astronomy. Below are some of my questions related to it and my understanding of their answers. I am not very confident about my understanding of them ...
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In terms of results, how similar is a bunch of telescopes across the globe to an Earth-sized telescope?
The Event Horizon Telescope emulates an Earth-sized telescope by syncing a bunch of radio telescopes across the planet to do take pictures with a small enough angular resolution to take pictures of a ...
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Reference request (explaining) how optical correlators combine light from multiple telescopes to produce ultra-high resolution interferometric images?
This is a reference or resource-request because it may be too challenging to explain in an answer post, but if you'd like to attempt a short summary as well, that will be great!
I have a basic ...
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