Astronomers using a French telescope say they've discovered 10 new distant planets, including twin Neptune-sized worlds and a rare Saturn-like planet.

An international team, including Oxford University scientists, discovered the planets using the French space agency CNES's CoRoT -- Convention, Rotation and Transits -- telescope, ScienceDaily.com reported Thursday.

The telescope detects exoplanets outside our solar system as they pass in front of, or "transit," their star.

One of the 10 new exoplanets detected is in orbit around what appears to be an unusually young star, a finding astronomers say is revealing.

"CoRoT-18b is special because its star might be quite young," said Suzanne Aigrain of Oxford University's Department of Physics, who is the lead British scientist for CoRoT. "Finding planets around young stars is particularly interesting because planets evolve very fast initially, before settling into a much steadier pattern of evolution."

"If we want to understand the conditions in which planets form, we need to catch them within the first few hundred million years. After that, the memory of the initial conditions is essentially lost."

Measurements suggest the star this planet orbits may be only tens of million of years old, she said.

"If this is confirmed, then we could learn a lot about the formation and early evolution of hot gas giant planets by comparing the size of CoRoT-18b to the predictions of theoretical models."