When an outer planet is at superior conjunction, it means that the planet and the Sun are aligned in the sky, with the Sun in the middle and the planet on the far side. This means:

* The planet is on the opposite side of the Sun from Earth. From our perspective, the planet is hidden behind the Sun.

* The planet is at its furthest point from Earth. This is because the Sun is between us and the planet.

* The planet is difficult to observe. The Sun's brightness makes it hard to see the planet during superior conjunction.

Here's a visual representation:

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Sun

/ \

/ \

/ \

Earth Planet

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Note: Superior conjunction is a term specific to outer planets (Mars, Jupiter, Saturn, Uranus, Neptune). Inner planets (Mercury and Venus) can also be at conjunction, but they are called inferior conjunction when they are between the Sun and Earth.