The planet was in the goldilocks zone and had a rocky composition. It had 1.2 G's of mass. As the planet was very young, there were no woody plants like trees present, and there was no animal life.
Shadows in Flight
The Herodotus' navigational computers were programmed to register habitable planets and send the information back to the International Fleet and later Starways Congress. However, when Bean saw this planet appear, he shut off communication with Congress as he thought he had found a world for his children to live on. As they approached the planet, Carlotta Delphiki noticed the Formic Ark that was also approaching the planet. After the two ships met and the Formic drones showed Bean's children how to cure Anton's Key, they made plans to settle the planet.