Halcyonic Planet

Any planet in a halcyonic system (i.e. KMT-2020-BLG-0414L b, WD1054–226 b, WD 1856 b, etc.)

There are also halcyonic dwarf planets, the only example of which is WD 1145+017 b.

In 2020, we discovered the first halcyonic planet around a white dwarf.