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WikiProject Astronomy / Astronomical objects  (Rated Start-class, Mid-importance)
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While the article is aimed at Extrasolar Moons, I think that the writer went a little off the target with this.

I concur, this has exceeded its reach. Also the article is long outdated (eg. 100 planets now 270+), and I am still searching for a reference to the Roman Numeral suggestion in the Nomenclature (??). - GabrielVelasquez (talk) 02:10, 30 December 2007 (UTC)

New Info[edit]

Hello, I just read this article and I attempted to insert some of the information about how to detect exomoons. I did not know how to insert a reference. Can someone do this? (talk) 20:11, 23 October 2008 (UTC)

Major Changes[edit]

Hello. I have added the reference as requested above.

I have expanded the section on detection methods to include a brief summary (one or two sentences) about each technique.

I have also added an image of an exomoon from Aurelia and Blue Moon article. This is the only image I could find of an exomoon within the Wikipedia Commons... 19:08, 11 November 2008 (UTC)

Habitable zone moon[edit]

Two high profile sources cited in the Canup & Ward (2006) Nature article referenced in this article are below:

  • [38] Williams, D. M. & Kasting, J. F. Habitable moons around extrasolar giant planets. Nature 385, 234–236 (1997)
  • [39] Barnes, J. W. & O'Brien, D. P. Stability of satellites around close-in extrasolar giant planets. Astrophys. J. 575, 1087–1093 (2002)

I think the concept of an earth sized moon existing within the habitable zone of a star is a very important one. It is clearly an established hypothesis. Certainly something that should be expanded. Polyamorph (talk) 08:56, 8 June 2010 (UTC)

If your going to go down this route, the possibility of upper limiting masses on both the satellite system and the individual satellites themselves should definitely be raised. And remember, our own solar system does contain a planetary satellite with a mass comparable to the Galilean moons squarely inside the habitable zone... Icalanise (talk) 17:19, 9 June 2010 (UTC)
All very good points but my point is that there are reliable sources (including Nature papers) which support the theory of "Habitable moons around extrasolar giant planets". I'm absolutely not suggesting we conduct any form of original research. Polyamorph (talk) 17:28, 9 June 2010 (UTC)
The other issue is how such a topic should be distinguished from general considerations of planetary habitability, and whether we can find reliable sources which discuss the issues that may be specific to habitability of planetary satellites (e.g. tidal effects or the interaction with radiation belts associated with the parent planet). As for the issue of formation, both those papers appear to discuss the issue of habitability in the event that such moons exist, rather than the consideration of forming such massive objects around a gas giant planet in the first place. Bear in mind that Jupiter's satellite system is more massive than Saturn's, in accordance with the scaling laws for gas giant satellite systems, but it formed multiple massive satellites rather than a "super-Titan". Icalanise (talk) 20:30, 9 June 2010 (UTC)
I do get your points and don't want to give any theory an undue weighting. Perhaps just a small expansion of the current statement in the "characteristics" section, expanding the key points given by Williams and Kasting, i.e. that the moons must be of sufficient size, have a suitable atmosphere and a magnetic field, posess a suitable orbit etc. Then wikilink to planetary habitability would be sufficient. Polyamorph (talk) 08:01, 10 June 2010 (UTC)
Off the top of my head, as I recall Jupiter and Saturn are believed to have formed multiple generations of satellite systems and the earlier "systems" fell/migrated into the parent planet. The Galilean moons are all relatively large because they formed in the same cycle, but Titan is suspected of possibly being the lone survivor of the previous "formation cycle". -- Kheider (talk) 17:27, 10 June 2010 (UTC)
One interesting possibility is that the differences between the architectures of the Jovian and Saturnian satellite systems arose because Jupiter managed to open up a gap in the solar nebula but Saturn did not. See [1]. Icalanise (talk) 21:59, 11 June 2010 (UTC)


Is there any proposal for a system of naming exomoons? — Preceding unsigned comment added by (talk) 15:52, 1 November 2011 (UTC)

Because no exomoons were discovered yet, there is no naming convention for such moons. I think such moons will be designated by the host star designation and a lower-case letter making an exoplanet designation followed by an Arabic number, e.g. HD 28185 b1 and Upsilon Andromedae d6. BlueEarth (talk | contribs) 00:57, 2 November 2011 (UTC)

Another candidate?[edit]

According to NASA, another possible exomoon has just been spotted. They're not sure yet (and not sure if or when they will be sure, as far as I can tell), so I'm not sure if this is worth adding or not. I'll just leave the link here: Xtifr tälk 01:10, 14 April 2014 (UTC)

It's the same candidate that was announced last December but it's in the news now. I've added mention in the article about different announcement and news dates. Astredita (talk) 13:58, 14 April 2014 (UTC)

Sub-brown dwarf with planet or Rogue planet with moon[edit]

Even if MOA-2011-BLG-262 is a planetary-mass object that doesn't necessarily mean its companion should be called a moon. Free floating planetary-mass objects can form from interstellar clouds just like stars and brown-dwarfs do. In which case they are sub-brown dwarfs. The satellites of sub-brown dwarfs could be considered planets just as the satellites of stars and brown dwarfs are planets. That MOA-2011-BLG-262 has a companion makes it unlikely to be a rogue planet that has been ejected from orbit around a star. Although The Survival Rate of Ejected Terrestrial Planets with Moons by J. H. Debes, S. Sigurdsson suggests it's not impossible for ejected planets to hold on to their moons, so the presence of a moon doesn't necessarily mean the main object is a sub-brown dwarf. Astredita (talk) 14:20, 14 April 2014 (UTC)

Another detection method[edit]

Radio emission I tried to add this to the article, but I could not manage the programming. Sorry. — Preceding unsigned comment added by (talk) 12:10, 14 August 2014 (UTC)