since I retired my sleep schedule is wildly erratic.
As for hours per night... I think probably around 6, average, but not necessarily 6 consecutive hours.
Bedtime: Before retiring I seldom was asleep before 1am.... meaning I rarely got over 4 hours of sleep per night. After retiring... no set time. I can go a month, or even more, going to bed at 8pm and then the following month go to bed at 3am.
Waking... I wake up at 5am every morning no matter when I go to sleep... too many years getting up at that time while farming. BUT.. these days when I wake at 5am I may or may not get up. If I don't get up I'll read for an hour our so and then go back to sleep for another 1-2 hours.
Naps... never took naps at all until about 2 years ago. Now I take a nap daily unless I'm away from home OR very busy with business.
I'm like you with 'research' but of a different type... for the most part. Most of my research is using Google Earth and studying geography and cultures... so I explore the world with Google Earth and when something intrigues me I switch to web articles relating to that area of the world. I also do this with 'space'.
I think Jay Leno once said he sleeps only 3 hours per night. And for his entire lifetime he has this habit of springing from bed when his morning alarm goes off, literally, hitting the floor the second his eyes open. - JamesJM