Well, Voyager is now well beyond much useful gravitational influence of any of the solar system's planets. What we have learned is that planetary gravity wells can be used to provide a boost to passing spacecraft. Since Voyager most spacecraft to the outer planets spend some time in the inner system first, performing slingshots from one planet to the next to increase velocity.
Each of these maneuvers robs a wee bit of the planet's angular momentum.
Planet Asteroid Meteoroid
No, the mass of a planet does not equal the size of that particular planet.
Voyager 2 was never on Neptune, but rather did a close flyby. During this flyby, Voyager 2 studied Neptune's atmosphere and the planet's largest Moon, Triton. It also discovered 6 new moons orbiting the planet.
Your mass does not change. Your weight, however, changes in proportion to the gravity of each planet.
There is no evidence, but the chances are very high. The explosive force of a supernova is enough to destroy a close planet or expel it into outer space. Even if it did not, the loss of mass would force any planet into a much greater orbit.
Because there are no moons, scientists have to observe deflections in the paths of space probes to work out the the mass of these planets.(Without going into the details, it is possible to work out the mass of a planet from a moon's orbital data. Even observations of an artificial satellite can be used. Otherwise, we need to observe the trajectories of space probes.)
The earth is most likely continuously gaining mass because it is continually being bombarded by meteors and meteorites of various sizes, which add mass to the planet. The only mass being lost from the planet is the small amount of lighter gases escaping from the upper atmosphere, and the minuscule mass lost as space probes leave the planet and do not take up a planetary orbit.
Mass of Planet X divided by volume of Planet X
That which occupies space and has mass is known as matter.
mass
In space, nothing: it has mass but no weight. On a planet or moon it depends on the gravity of that planet or moon as well as the mass of the spaceship.
You cannot. The only thing you can change is how many probes you have. That is done by going to the fuel station and purchasing them.
Planet Asteroid Meteoroid
Because the mass of the planet holds it down.
it would be a piece of mass....roaming in the space(universe)
No your mass would not change at all if you traveled from planet to planet. Mass is the amount of space an object takes up. Since different planets have different levels of gravity pushing down on you then your weight would change but unless for any reason you lost/gained weight or grown any taller/shorter your mass would not change traveling planet to planet.
Your mass stays the same but your weight is different because it is the force that the planet's mass attracts your mass with. So if you are on a small planet your weight is less. A body with 100 pounds mass has a weight of 100 pounds on the Earth but only 17 pounds on the Moon, and zero pounds in space.