Editing Astronomical radio source (section)

==Sources: Solar System==

===The Sun===
As the nearest star, the [[Sun]] is the brightest radiation source in most frequencies, down to the radio spectrum at 300&nbsp;MHz (1 m wavelength). When the Sun is quiet, the [[Cosmic background radiation|galactic background noise]] dominates at longer wavelengths. During [[geomagnetic storm]]s, the Sun will dominate even at these low frequencies.<ref>{{cite book|author=Michael Stix|title=The sun: an introduction|url=https://books.google.com/books?id=wxHN9jP-mNMC|year=2004|publisher=Springer|isbn=978-3-540-20741-2|access-date=2016-09-23|archive-date=2021-04-26|archive-url=https://web.archive.org/web/20210426225220/https://books.google.com/books?id=wxHN9jP-mNMC|url-status=live}} section 1.5.4 The Radio Spectrum</ref>

===Jupiter===
[[File:Jupiter's Magnetosphere animation.png|thumb|Magnetosphere of Jupiter]]
Oscillation of electrons trapped in the  [[magnetosphere of Jupiter]] produce strong radio signals, particularly bright in the decimeter band.

The magnetosphere of Jupiter is responsible for intense episodes of radio emission from the planet's polar regions. Volcanic activity on Jupiter's moon [[Io (moon)|Io]] injects gas into Jupiter's magnetosphere, producing a torus of particles about the planet. As Io moves through this torus, the interaction generates [[Alfvén wave]]s that carry ionized matter into the polar regions of Jupiter. As a result, radio waves are generated through a [[cyclotron]] [[Astrophysical maser|maser mechanism]], and the energy is transmitted out along a cone-shaped surface. When Earth intersects this cone, the radio emissions from Jupiter can exceed the solar radio output.<ref>{{cite web |date=February 20, 2004 |url=https://science.nasa.gov/science-news/science-at-nasa/2004/20feb_radiostorms |title=Radio Storms on Jupiter |publisher=[[NASA]] |access-date=August 23, 2017 |archive-date=May 16, 2017 |archive-url=https://web.archive.org/web/20170516195522/https://science.nasa.gov/science-news/science-at-nasa/2004/20feb_radiostorms |url-status=live }} ([https://web.archive.org/web/20070213220639/https://science.nasa.gov/headlines/y2004/20feb_radiostorms.htm archived version])</ref>

===Ganymede===
[[File:Ganymede JunoGill 2217.jpg|thumb|Jupiter's moon Ganymede]]
In 2021 news outlets reported that scientists, with the [[Juno spacecraft|''Juno'' spacecraft]] that orbits Jupiter since 2016, detected an [[Frequency modulation|FM]] radio signal from the moon [[Ganymede (moon)|Ganymede]] at a location where the planet's magnetic field lines connect with those of its moon. According to the reports these were caused by [[Cyclotron radiation|cyclotron maser instability]] and were similar to both [[WiFi]]-signals and Jupiter's radio emissions.<ref name="futurism-ganymede">{{cite news |title=NASA reportedly detects signal coming from one of Jupiter's moons |url=https://futurism.com/the-byte/nasa-signal-jupiters-moon |access-date=11 February 2021 |work=Futurism |archive-date=28 January 2021 |archive-url=https://web.archive.org/web/20210128234759/https://futurism.com/the-byte/nasa-signal-jupiters-moon |url-status=live }}</ref><ref>{{cite news |title=Discovery in space: FM radio signal coming from Jupiter's moon Ganymede |url=https://www.abc4.com/news/discovery-in-space-fm-radio-signal-coming-from-jupiters-moon-ganymede/ |access-date=11 February 2021 |work=ABC4 Utah |date=9 January 2021 |archive-date=11 February 2021 |archive-url=https://web.archive.org/web/20210211043228/https://www.abc4.com/news/discovery-in-space-fm-radio-signal-coming-from-jupiters-moon-ganymede/ |url-status=live }}</ref> A study about the radio emissions was published in September 2020<ref>{{cite journal |last1=Louis |first1=C. K. |last2=Louarn |first2=P. |last3=Allegrini |first3=F. |last4=Kurth |first4=W. S. |last5=Szalay |first5=J. R. |title=Ganymede-Induced Decametric Radio Emission: In Situ Observations and Measurements by Juno |journal=Geophysical Research Letters |date=2020 |volume=47 |issue=20 |pages=e2020GL090021 |doi=10.1029/2020GL090021 |bibcode=2020GeoRL..4790021L |s2cid=224963913 |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL090021 |access-date=27 February 2021 |language=en |issn=1944-8007 |archive-date=7 March 2021 |archive-url=https://web.archive.org/web/20210307072803/https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL090021 |url-status=live }}</ref> but did not describe them to be of FM nature or similar to WiFi signals.{{Clarify|date=February 2021}}