Changing the current changes the "what" of an electromagnet

An electromagnet is only magnetic when there's current going through
the wire.  If there's no current flowing, then the electromagnet is just a
lump and doesn't attract anything.

The strength of the electromagnet depends on the amount of current
that's flowing through the coil of wire around it.

Changing the current immediately changes ==> the magnitude of the
magnetic field, ==> the strength of the electromagnet, and what it's
able to pick up.

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.