His style of planetary romance has ceased to be written and published in the mainstream, though his books remain in print.

Some critics distinguish between space opera and planetary romance.

In the true planetary romance, the world itself encompasses-and survives-the tale that temporarily illuminates it.

Remains is more of a "planetary romance", the action taking place within the confines of the Solar System.

It may be classified as science fantasy or planetary romance.

Most of Brackett's science fiction can be characterized as space opera or planetary romance.

The series is set in the far future and possesses some of the features of space opera and planetary romance.

The novel can be classed as a planetary romance.

While both stories are space operas, only Brackett's is a planetary romance.

Given the cross-pollination between planetary romance and space opera, many stories are difficult to classify as being wholly one or the other.