1) The Voyager 2 spacecraft in 1989.
2) The Hubble Space telescope.
3) Earth based methods, especially spectroscopy.
No humans have visited the planet Neptune.
Neptune is a gas giant, so it is uninhabitable to humans.
No. There is no oxygen in Neptune's atmosphere
neptune is a huge gas giant. it has winds reaching up to 159 miles per hour. it is the 8th planet from the sun.
No, humans could not live on Neptune. Neptune's extreme cold temperatures, high wind speeds, and lack of a solid surface make it inhospitable to humans. Additionally, the planet's atmosphere is mainly composed of hydrogen and helium, which are not breathable for humans.
No, humans have not been to Neptune and there are no known pie vendors on the planet. Additionally, the extreme conditions on Neptune would make it impossible for humans to survive without special equipment.
Planet Neptune is the eighth planet from the sun.
It may be possible in the future, but today we are not able to travel that far.
Neptune's vision is blue and it is the 8th planet. There is Neptune because it is a planet.
Neptune is the eighth and furthest planet from the Sun.
There are many websites on the internet that contain information on the plant Neptune. Some such websites would be Wikipedia, and National Geographic.
No so far no man has set foot on the planet Neptune.