Questions tagged [radio]
Questions about the part of the electromagnetic spectrum with wave lengths longer than those of infrared radiation.
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Has optical interferometry been done at radio frequency using heterodyning with a laser in a nonlinear material?
If one collects narrow band optical emission from a large telescope with frequency $f_1$ and mixes it in a nonlinear crystal with laser light of a nearby frequency $f_2$, it would produce two new ...
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Current topics on Radio Astronomy and looking for advice
Background and Question: I'm an undergraduate student interested on Radio Astronomy. I consider myself enthusiastic about it and I project myself following this "path" so I'd like, ...
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Can one build a distributed radio telescope?
I understand some radio telescopes are built as arrays of receivers. Could one build an array from a heterogeneous set of receivers in scattered locations? Suppose a large number of persons each ...
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Why space-based VLBI scattering sub-structure is "Hopefully, a new promising tool to reconstruct the true image of observed background target(s)"?
@HDE226868 mentioned in the observatory that the GBT@20 – The Celebration; Twenty Years of Innovation and Discovery was going on. There are plenty of YouTube videos and slide sets available as links. ...
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How do we know that comets definitely mase and not just fluoresce? What is it about 18-cm lines that indicates that is really masing per se?
Wikipedia's Astrophysical_maser#comets mentions some anecdotes of notable masers associated with comets, and Maser emissions from comets begins:
The 18-cm lines of the OH radical are the only well-...
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How bright is the Sun in S-band?
As far as I can tell when the Voyagers listen to Earth they have the Sun in the same beam. I never did calculate how bright a blackbody Sun would be because I have no idea if that's representative of ...
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What does the Sun "look like" below 100 MHz?
Radio2space.com's The Radio Sun says:
At very low frequencies (below 0.1 GHz) and therefore at very long wavelengths (> 3m) the solar disk appears much bigger and brighter in the center, and its ...
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What's known about Odd Radio Circle appearance? What would they look like if we could see them? Are they transparent/translucent in radio, or opaque?
update: March 2022:
Phis.org: Astronomers reveal best image yet of mysterious odd radio circles in space
Science Alert: Weird Circular Objects Observed in Space May Finally Be Explained
MNRAS: ...
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