As you can tell we are very into the Astrophytum genus right now and for good reason. These lil guys are mesmerizing and quite fascinating. They are native to Mexico's Couhulia region, they receive strong light and very cold nights. We recently discovered after we left ours outside overwinter last year and it was still kicking along and actually grew a little. These are notoriously slow grower but these truly are generational plants, seeing 30-40 year old specimens are mindblowing since they can reach to about 3 ft tall at maturity.
These need that nice South or West exposure and watering every 3-4 weeks during Spring to Fall. Then during the winter you're going to want to water every 6-7 weeks.