Voyager 2 passed by Neptune on August 23, 2009
space probes
Only one spacecraft has visited Neptune: NASA's Voyager 2 probe, which made a flyby of the planet in August 1989. Voyager 2 provided our first close-up images and scientific data of Neptune and its moons.
The answer depends on "before what".
Distance from Earth.
Sputnik and space probes are artificial satellites
Jupiter
The only probe that has reached Neptune so far was Voyager 2.
artificial satellites , probes, telescope etc
No, Voyager 2 is not the only spacecraft to study Neptune. The Hubble Space Telescope and the Keck Observatory have also observed Neptune. Additionally, the European Space Agency's Huygens probe studied Neptune's moon Triton.
Not exactly. The Voyager 2 space probe did a flyby of Neptune, but since it never actually orbited the planet, it can't be considered a satellite. Neptune does not have a solid surface, so nothing could ever land on it.
The Voyager 2 went to Neptune on it's last stop in the solar system.
They are called Space Probes.