A distant solar system that centers on the star HD 10180 has at least 5 planets, and most likely two more. It's possibly the most populous solar system we've spotted, other than our own. And it's pretty weird.
Astronomers spotted the planets using spectroscopic analysis and the "wobble method," where they look at slight wobbles in a star. These wobbles are caused by the gravitational forces from planets rotating the star, and researchers can extrapolate probable size and mass of the planets based on what I hope someday will be called wobble analysis. In the video above, you can watch as we zoom through space, all the way to the HD 10180 system.
Space.com's Tarik Maliq has the story:
The five strongest wobble signals were caused by planets with masses similar to Neptune, between 13 and 25 times the mass of the Earth. Though these planets are relatively large, they are located close to their parent star and race around at intervals that range from just six days to 600 days. The closest planet is not quite 5.6 million miles (9 million km) from HD 10180, compared to the 93 million miles (150 million km) separating Earth from the sun, a distance also known as an astronomical unit. The distance of the farthest one from its star is about 1.4 AU.
When compared to our solar system, all of these planets would fit inside the orbit of Mars and appear to have nearly circular orbits.
The wobble method for detecting alien planets also suggested more worlds are orbiting HD 10180, one of them up close and the other far off . . . One of these extra planets, if confirmed, would be much like Saturn, with at least 65 times the mass of Earth and year that lasts 2,200 days.
The other potential planet is the most tantalizing for astronomers. If confirmed, it would be the least massive world ever found outside our solar system, with a mass just 1.4 times that of Earth. It is thought to orbit extremely close to the star – just 2 percent of an AU – and completes its circuit in only 1.18 Earth days, researchers said . . . This planet would probably be a small, rocky world similar to the hellish planet Corot-7b, which orbits close to a different star. There the daytime temperatures can reach 4,000 degrees Fahrenheit (2,200 degrees Celsius), with nighttime lows of minus 350 F (minus 210 C).
Sadly, none of these planets is in the sweet spot where water is liquid so the HD 10180 system isn't a good target for colonization.
Video by Michael Adams