Second Landing by Murray Leinster — Read

The continent Chios is. the only considerable land-mass on / the planet. It is densely covered with vegetation, and its former / inhabitants must have had cultivated crops and very probably a / dense population. However, its constant daylight negates the / idea of the introduction of Earth plants, and the poor flavor / and indifferent quality of such edible plants as are known / makes subsistence on its native products a far from attractive / prospect. In case of emergency, nourishment will be found / in. -- _Astrographic Bureau Publication 11297. Appendix to Space / Pilot, Vol. 460. Sector XXXIV, p. 80._

There was no night or day upon Thalassia. In theory, at this particular part of its year, the sun Elektra rose from somewhere along its southeastern horizon and for not quite one hundred and fifty hours crept upward in the eastern sky, and then for the same length of time descended slowly toward the northeast. As it set, the star-clustered Canis Venitici rose in the southwest and rose for a similar number of hours and declined for the same to the northwest. At other seasons these directions were reversed, and there was also a time when the sun rose due south and set due north. Then there were eclipses. All of which resulted from the fact that Thalassia and Aspasia revolved about each other once in twenty-five days (Earth measurement) with their common axis in the plane of the ecliptic, and had no diurnal rotation at all. But the important thing was that Thalassia had no clear-cut day and night.