Astronomers make first clear detection of a moon-forming disc around an exoplanet eurekalert.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from eurekalert.org Daily Mail and Mail on Sunday newspapers.
How are solar systems born?
Many of us remember those school-room models of our Solar System, with tiny wooden planets rotating at the ends of their wires around a bright-orange painted sun. But how accurate is the model? Do the planets really align in a plane, or do their orbits crisscross around the sun at different angles? It turns out the toy isn’t too far off, at least in this one aspect.
Our solar system is actually pretty flat, with most of its planets orbiting within three degrees of the plane of the Earth’s orbit around the sun, called the ecliptic. This flatness extends to the asteroid belt between Mars and Jupiter, though some members of the region of icy objects past Neptune called the Kuiper belt are more extreme, with inclinations up to 30 degrees.
IMAGE: ALMA (ESO/NAOJ/NRAO), I. Czekala and G. Kennedy; NRAO/AUI/NSF, S. Dagnello
“What’s interesting is not just that we see the disk rotating, but that we are starting to sense the ways in which the velocity of the field deviates from its expected rotation at a very subtle level,” said Czekala. “It’s like watching a river flow downstream. Sure, you see the bulk flow of the river, but when you look at the eddies and turbulent waves, you can infer that there might be a submerged rock in one area or even a large underwater cavern in another. It’s what lies underneath that gets me really excited.”