My story has two planets separated by ~35,000 miles of empty space- tidally locked through a magic "planetary anchor" light rope that connects the two planets and keeps them at that exact distance.
The two planets are earth-like and I want them to be earth-ish habitability, with a bit more wildness due to the rotating nature of the binary planets. The planets orbit around the tether every 36 hours. I'm thinking they're on the solar plane or with <10 degrees of deviation.
Year length, if it's relevant, is earth year. Sun= earthlike/to be decided.
Would there be a normal 18hr day/ 18 hr night cycle (with slight seasonal variation), or would there be two nights- one at midday and one at the normal time?