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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Do we have the technology to create a satellite telescope constellation that uses interferometry?
Apologies for putting the bulk of the question in the description. I'm honestly not sure how to ask this properly. The idea for this question came from a Vsauce video from several year ago I can't ...
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About angular diameter, parallax and image of the nearest neutron star RX J185635-3754
I have a big doubt about our allegedly nearest (X Ray isolated) neutron star, also known as the Walter star, one of the members of the "Magnificent Seven stars": RX J185635-3754.
So I came ...
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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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Could we hear alien radio transmissions using radio interferometry?
Suppose money and engineering wasn't a concern. Could we actually build a bunch of radio telescopes in space, and use radio interferometry, so that we could actually hear the sort of radio ...
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Telling bounces in LIGO interferometer
How do they know the number of times the laser bounces back and forth, in the 4 km arms of the interferometer, before the laser light is picked out to the reading sensor?
See under “The Longer 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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Can the interferometer called "Gravity" measure "a few centimeters on the Moon"?
Phys.org's Very Large Telescope sees star dance around supermassive black hole, proves Einstein right links to several ESO videos, including Interview with Reinhard Genzel (in English). After ...
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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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Giant variation of the proposed eLISA mission using reflectors on Earth and the Moon possible?
I was thinking about the proposed ESA mission eLISA, which is essentially a space version of the LIGO experiment, and it occurred to me that trailing three satellites behind the Earth's orbit seemed ...
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Squared visibility in astronomy
Why is preffered to use squared visibility instead of visibility in long-baseline interferometry, please?
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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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How does Very Long Baseline Interferometry work?
According to internet sources, this technique increases the effective diameter of the telescope, thus improving the angular resolution of the telescope. However I don't understand how this actually ...
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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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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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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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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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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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Estimate upper limits on flux values in the case of a non-detection?
I have ALMA data which are non-detections of some spectral lines in a protoplanetary disk. The data is in the form of spectral cubes. I am hoping to estimate an upper limit on the flux of each of the ...
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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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What is stopping Event Horizon Telescope the size of the Earth’s orbit?
There is a proposal to include a radio sensor in a telescope going to the Sun-Earth L2, getting 120x improvement in angular resolution to EHT. Knowing nothing about interferometry, it seems pretty ...
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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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What does a narrow-band "point spread function" look like for long exposures from the VLT's large interferometric aperture?
In interferometric radio astronomy UV plots are the first step in understanding what a point spread function (PSF) will look like for a given location in the sky observed over a period of time. The ...
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Is it possible to overcome the problem of blind spot(s) of current gravitational wave detectors?
If gravitational waves (GWs) pass through specific points (which are known as blind spots), current GW detectors aren't able to detect the passing waves. In the future, will we be able to completely ...
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If we put a radio telescope on Mars and use it in array with earth radio telescopes, how much will we able to see?
If we put a radio telescope on Mars and use it in array with earth radio telescopes, how much will we able to see? Will it allow us to see planets, like we do with black hole?
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Response function of LIGO
"Laser Interferometer Gravitational-wave Observatory" (LIGO) is a marvel of precise engineering and the world's largest gravitational wave observatory. LIGO, which consists of two massive ...
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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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Are there any space-based observatories that use interferometry?
Ground-based interferometers such as ALMA have enabled many discoveries. It seems like sending a fleet of small telescopes would be feasible (smaller telescopes are easier to send into space than ...
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Is radar interferometry used, or feasible, for ground based astronomy?
I've heard of "interferometric synthetic aperture radar" being used for Earth observation from satellites and airplanes. Is active radar used interferometrically for astronomical purposes too? Such as ...
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Have interference effects (in space) ever been observed by a single instrument, as opposed to interferometry?
Not asking about:
Interferometry can be done with multiple instruments who's light paths or signals are combined interferometrically, or even between different parts of a single aperture, e.g.
What ...
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Will the Magdalena Ridge Optical Interferometer be able to image extended objects like the surface of the Moon?
Inspired by several questions:
When will a moon landing site be visible via telescope?
Could the E.H.T. produce an image of the human artifacts on the moon?
Picture of equipment left on the Moon?
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