By accretion, through gravitational attraction and collision.
New planets are not forming in our solar system. When you get beyond Neptune, there is large grouping of stellar debris called the Kuiper Belt. The Kuiper Belt has enough material to become another planet, but it orbits around the sun too slowly for the material to combine. The planets formed by having asteroid-like rocks collide with one another, and the objects in the Kuiper Belt are spread out too far and don't have enough moment to form anything. There may be new planets forming around different stars. So far there have been around 800 stars found to have planets orbiting them, but there is no indication when those planets were formed. There may be new planets forming around different stars.
Meteors and dust from space
No new planets have been added 08/2011
Not in our own solar system. The orbits of all the planets in the solar system have stabilized, and there isn't enough mass in the remaining asteroids to form a new planet. Else where, however, there are solar systems that are still forming, with new planets that are yet to form.
volcanic
Yes. As a new star is forming it is surrounded by a disk of gas and dust called a protoplanetary disk. Planets, asteroids, and comets all form from this disk.
Sort of. Planetary scientist theorize that when the sun was coalescing (forming), a lot of gas and dust were left over and began orbiting the new star. This is referred to as an accretion disk. This belt of particles over time began to collect in clumps, and as these clumps grew, the developed their own gravity wells, in turn sucking in more and more matter. Some formed planets, some formed other bodies that often crashed into the newly forming planets and added to their mass.
Volcanic Mountains
No... There are no new planets!
Yes, when magma rises from an ocean ridge, it can produce new material through a process called seafloor spreading. As the magma reaches the surface, it cools and solidifies, forming new oceanic crust. This process contributes to the continuous expansion of the seafloor and the formation of new crustal material.
there is 7 new planets
Volcanic eruptions are one process that adds new material to crust. Lava from the volcanoes eventually cool, forming new land. Sea floor spreading also adds new material to the crust.