5th moon or star

[eriksters]

Hey people smarter than me,

Im outside looking at jupiter and I can clearly see 5 moons. I dont know if the fifth one is a star or a moon! The pic was taken with my phone (Io is realy close to jupiter)

[ronin]

Every time this comes up it is a star.

The next one down (moon) is too small to be seen except with a big scope, no idea how big.

Seems that Jupiter ambles round and gets in front of a few stars that match the brightness of what is often taken as another moon. Hence it gets asked 3 or 4 times a year.

With the number of stars it is inevitable that some will eventually line up and look right.

Reminds me to go find out what the next moon down is.

[ronin]

After the 4 Galilian moons the next biggest is Himalia then Amalthea. Amalthea was discovered first so guess it is in a more obvious orbit.

Himalia is 0.00014 the size of the smallest of the Galilian moons, Europa, it is 170Km in diameter.

Measurement indicate it is spherical, but that could be it is too small to get an accurate measuement of.

Not sure how big a scope is required but guessing a BIG one, a Tasco 60 isn't going to make the grade.

[Paul73]

Has anyone bagged number 5?? Surely the glare from Jupiter would make it virtually impossible?

Paul

[eriksters]

Ok thanks guys! Ima go to Iceland now so I can stick my popsicle hands and feet into a volcano!

[Hyperion76]

gas giants is a great app for the outer planets and their moons identification

[Dave In Vermont]

Here's a little piece of freeware that shows you which of the 4 Moons is which and where they are at any given time. Just enter your data:

http://www.astrosurf.com/rondi/jupiter/

Clear Skies,

Dave

[goose35]

Had the same dilema this very evening myself.

Figured id discovered a new moon but alas when i thought about it , its a star

[swamp thing]

I was talked into having a look for the fifth moon (very reluctantly) by Mark (mdstuart) at SGLX. We couldn't nail it with my 20". Conditions were far from superb but it gives you some idea that this is not going to be a walk in the park even with large glass.