Extra Solar Planets Interactive (135.0K)
Is it possible that the “wiggle” of a star can tell astronomers about worlds in other star systems? Yes, it is, and this Interactive will show you how. When planets orbit a star, they impact the motion of the star, and by observing that motion, astronomers can infer the presence, mass and distance of the planet. Things get more complicated with there are multiple planets. Observe Earth’s impact on the Sun’s motion, and you will understand why Earth-type planets around other stars are hard to detect. Compare that to a “Hot Jupiter” and see how much more readily it can be seen. Then observe the multiple planet system to see how its much more complex interactions are reflected on the graph.
Nu Andromedae has three jovian type planets orbiting around it. Let's use the orbit of the innermost, and Newton's revision of Kepler's third law, to weigh its star.
While in the previous question, we used the inner most jovian of Nu Andromedae to weigh the star, now let's look at the distances of the two outer jovians that orbit this star, with comparisions to our solar system.
On June 8, 2004, the planet Venus transited the Sun. We now know of several cases where hot jupiters also pass in front of their stars, and even amateurs with photometers are helping monitor hundreds of stars for such recurrent dimmings. What can they tell us about the planets involved?
In 1995, the first planet orbitting another star was discovered, and since then, the count of other solar systems has passed one hundred and growing daily. But to date all are comparable to at least Uranus in size. How can we find Earths instead?