Where Jupiter's four big moons are tonight: east or west of the planet, behind it or in its shadow, drawn north up, inverted or mirrored to match your eyepiece.
Frequently asked questions
Why does the diagram look flipped compared with my telescope?
Many telescopes show the sky upside down, and a star diagonal mirrors it. Pick the view that matches your eyepiece; the moon names and the table stay the same.
Can I see the moons with binoculars?
Usually, yes. Steadily held 7×50 or 10×50 binoculars show up to four faint, star-like points in a line beside Jupiter: Io, Europa, Ganymede and Callisto. Ganymede and Callisto are the easiest because they swing farthest from the planet, up to about 6 and 10 arcminutes in early 2027; Io never strays more than about 2 arcminutes and is often lost in Jupiter's glare. Rest the binoculars on something steady or use a tripod: around the February 2027 opposition Jupiter is almost overhead at midnight from Guyana, so a reclining chair helps. At any moment a moon can be hidden behind Jupiter, in front of it or in its shadow; the diagram shows which.
Does this show when a moon will disappear behind Jupiter?
Not yet. The tool shows where each moon is at the time you choose. Event times will be added only after they are checked against published tables.
When is Jupiter best placed from Guyana?
Around opposition on Wednesday 10 February 2027 at 20:29 GMT-4. That night Jupiter is 45.2 arcseconds across and passes 81.6° high at 00:08 from Georgetown, almost overhead.