How do we think the "hot Jupiters" around other stars were formed? How do we think the "hot Jupiters" around other stars were formed? They formed as gas giants beyond the frost line and then migrated inwards. They formed as dense, rocky planets close to the star in the same orbits that they are seen today. Many planets were formed around the star but coalesced into a single planet close in. They formed as gas giants close to the star in the same orbits that they are seen today. They spun off from the young star when it was rapidly rotating.

One of the leading theories of hot-Jupiter formation holds that gas giants in distant orbits become hot Jupiters when the gravitational influences from nearby stars or planets drive them into closer orbits. They formed as gas giants beyond the frost line and then migrated inwards.

Explanation:

In the migration hypothesis, a hot Jupiter forms beyond the frost line, from rock, ice, and gases via the core accretion method of planetary formation. The planet then migrates inwards to the star where it eventually forms a stable orbit. The planet may have migrated inward smoothly via type II orbital migration.

Hot-Jupiters are heated gas giant planets that are very close to their stars, just a few million miles distant and orbiting their stellar hosts in just a few days. The reason why there isn't one in our Solar System is down to its formation. All gas giants form far from their star but then some migrate inwards.

Hot-Jupiters will just happen to transit about 10% (that is, since orbital planes) this is consistent with the rate expected from geometry of. The actual frequencies of hot Jupiters around normal stars is surprisingly hard to figure out.