Moonless Jupiter?

[Nik271]

Yesterday at about 6:45pm I had a brief opportunity to observe Jupiter with just one moon visible: Callisto. Ganymede was just eclipsed, Europa was transiting the disc of Jupiter while Io was occulted by the shadow of Jupiter. It was a most unusual sight, I was lucky that the clouds cooperated and I managed to observe it by sheer luck since I didn't check it up in advance. The seeing was decent as well, I could use x140 with my 102mm refractor.

This set me thinking: can it happen that Jupiter appears without any moons visible? The wonders of the internet search engines gave me the answer quickly: yes it can happen but not often, only once in a few years. In 1910 an amateur Italian astronomer Enzo Mora computed (by hand!) the dates of such evens for the 20-th century. A later paper by Jean Meeus in Journal of  BAA added a list for the 21 centrury (I assume he used computers or at least electronic calculators in 1987). His paper is available here:

https://articles.adsabs.harvard.edu//full/1987JBAA...98...35M/0000036.000.html 

According to his calculations the next such event is in the morning of 28 July 2033 and will be visible from the UK (if there are clear skies of course).

It's a long wait sadly. The previous three events in 2019,2020 and 2021 were during the day from the UK.

So I wonder if anybody here has observed such an event in the past?

 

Clear skies! ( and especially on 28 July 2033 🙂 )

 

Nik

 

[Davidv]

Hi Nik,

I did indeed observe one of these events well over ten years ago, maybe twenty. I'd been in the pub with my dad having a drink and as I was aware this was happening we made a point of observing it with my 8.75" Dobsonian when we got back to my house. There really were no moons visible - nothing to do with having a skin full. A most extraordinary sight.

I was out at about half six last night and was surprised to see only one moon. I did see two appear a bit later but had no idea if the missing moons were transiting, occulted or eclipsed. I couldn't see any shadow transits.

Cheers and clear skies.

Dave

[Nik271]

Thanks Dave, you are a lucky man, there were just a handful of moonless Jupiters  in the past 20 years. They seem to be rarer than a total solar eclipse except that of course when they occur they can be seen by anybody on half the planet, whereas a total solar eclipse is visible from a tiny area.

[RT65CB-SWL]

Hi @Nik271

I too have viewed a ‘moonless’ Jupiter. It is kind of surreal. It was fun and mesmerising watching the four of them re-emerge as well.

Edited January 27 by RT65CB-SWL

[Mr Spock]

I missed the one moon night due to cloud  Hopefully I'll still be around in 2033 

[Nik271]

Perhaps we will see Jupiter with one moon much sooner. I run Stellarium until May watching the moons dance around Jupiter but could not spot a time when just one will be visible. I wonder if anybody has made a study of this.