Six planets are visible from Earth without any optical equipment
except your eyes.
Neither Mercury nor Venus are visible at midnight. Both planets are closer to the Sun than the Earth is.
Venus is the planet that looks brightest from Earth.
Venus would never be visible as a crescent phase because it is an inner planet whose orbit is between Earth and the Sun. This means that Venus can never appear to us in crescent phase, as it would always show either a full or nearly full phase when viewed from Earth.
yes
There is no planet that's always only visible in the morning. The part of the day during which each planet is visible changes, as both the Earth and the planet revolve around the sun.
Venus is considered the brightest object (and planet) to be seen from Earth (Being visible with the naked eye even in light-polluted cities).
Noplace. Earth isn't a star, and isn't visible in the sky from Earth.
earth has never visited another planet
Never.
From Earth it would be the Sun, which, however not a planet, but a star
The moon orbits the Earth, so it is always visible from some point on Earth.
Never. Period.