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A few weeks ago, I suggested a somewhat off-topic question:
"How fast is Halley's Comet moving away from the Sun today in knots [...]? And when will that speed be zero?"

Antoine, thank you for contributing on this when I first posted, but I think I wasn't specific enough in my question. When I asked how fast it's moving "away" from the Sun, I meant its heliocentric radial velocity. Right now (apparently) it's still moving outbound --radial distance from the Sun is increasing. So how fast is that today? And when will it start to fall back towards the Sun in a radial velocity sense? How could you determine this from online resources? What would be the "gold standard" resource online for this question?

I also asked why that date when it hits zero outbound speed doesn't match the date that's halfway between the perihelion in 1986 and the next perihelion in 2061. Can we address this difference in any qualitative way? Is the comet late to aphelion? There are a few more details in my original post on this topic.

Frank Reed