Detecting the gravitational effect of an orbiting planet by looking for the Doppler shifts in the star's spectrum.
Jupiter and Saturn. Or if you mean in general, planets.
Several methods are used. In many cases - perhaps most cases - the planets are discovered due to their gravitational effect on the star. That is, the star "wobbles" due to the gravitational pull of nearby planets, especially if the planets are very massive (planets more massive, "heavier" in popular language, than Jupiter, are easiest to detect), and close to the star. In some very specific cases, the planet may go right in front of the star, and make it become slightly dimmer once every orbit.
Planets not orbiting a star but instead orbiting the galactic center are referred to as rogue planets, or nomadic or interstellar planets.
Planets do not have suns orbiting around them. Suns have planets orbiting around them. The planet in our solar system with the highest number of discovered moons orbiting around it is Jupiter, with over 100.
Extrasolar planets are planets found orbiting stars other then our own.
The inclusion of some alternative methods is required to allow an answer to be written.
Jupiter and Saturn. Or if you mean in general, planets.
Orbiting stars. We know of eight planets orbiting our Sun, and we know of over 300 planets orbiting other stars.
Our solar system and all the planets and asteroid that surround it are orbiting the sun as the sun's mass attracts them to it through the force of gravity. The Universe however is not.The galaxy, is centered around a "super massive black hole" according to some scientific discoveries.
There may be planets orbiting stars in the constellation Gemini, but planets do not orbit whole constellations.
A series of planets orbiting a star is called a Solar System
In a solar system you find a few planets orbiting a star. In a galaxy you find billions of stars orbiting a galactic nucleus (probably a super massive black hole).
More massive planets have more gravitational pull. If a satellite were to pass by Earth and Jupiter at the same distance from each planet, the satellite would be more attracted to start orbiting Jupiter because of its pull. The more massive a planet is the more likely it is to get a satellite to orbit it.
Planets not orbiting a star but instead orbiting the galactic center are referred to as rogue planets, or nomadic or interstellar planets.
No. Other stars have been found to have planets orbiting them.
Several methods are used. In many cases - perhaps most cases - the planets are discovered due to their gravitational effect on the star. That is, the star "wobbles" due to the gravitational pull of nearby planets, especially if the planets are very massive (planets more massive, "heavier" in popular language, than Jupiter, are easiest to detect), and close to the star. In some very specific cases, the planet may go right in front of the star, and make it become slightly dimmer once every orbit.
There are no planets orbiting Earth.