40.)Deneb IV
This is where the long journey of the USS Enterprise D started. And this is the planet called the "Far Point Station". This planet is also a vacation spot and a stop before the great frontier of space. This station is almost on the fringes of unknown space. The inhabitants of this planet are called the Bandi. And they have a enity trapped and enslaved and it produces geo thermal energy for them. As it turns out the base is the enity itself when the USS Enterprise D comes to investigate the station. And this is also Q's first vistit. This is a class M planet.
References:TNG(First episode)Encounter At Farpoint

  41.)Drema IV
This is a class M planet and is very unstable. This planet has alot of volcanic activity and is also one of the biggest dilithium deposits known in the galaxy. This planet also has life. Although they are not aware of life in the stars and have primitive technology. This planet is located in the Selcundi Drema planetary system. The USS Enterprise D comes and restores the planet back to stability. Also eliminating the dilithium deposits in the process.
References:TNG Pen Pals

  42.)Dytalix B
This planet has a few names. Mira V,Omicron Ceti A,Dytalix B. It is called Dytallix B because of the company that mines on the surface and most people that have buisiness here and when they talk about it they call it Dytallix B. This planet is class M and is uninhabited and is a very windy planet. This planet does not rotate like earth. It's rotation is locked. its sunside has high temperatures around about 180 degree's(high for human standards). Most of the mines are located along the border of the light and dark sides of the planet where it is quite a bit cooler. The mines have played out their deposits and are deserted. This was also a meeting place for 3 captains that have found treachery in the Federation and met to stop it.
Reference:TNG Conspiracy

  43.)Dyson Sphere
A large sphere that was built around a G star. This sphere is around 200 million KM in diameter and is large enough to fit 250 earth sized planets inside. Named after a scientist who made the theroy. Freeman Dyson of the 20th century. The makers of this sphere are unknown and all records seem to have been lost. USS Jenolen was crashed on the surface outside of the sphere and inside was Chief Engineer of the Enterprise A Scott Montgomery and he was in the transporter buffers. The enterprise D came along and got trapped inside the sphere and used the Jenolen to escape.
Preview
References:TNG Relics