What do the 'Specific Time' functions in RemoteControl api/stelaction do?

[DrRichardDaystrom]

I've been exploring the RemoteControl API and I see that there are a whole set of 'Specific Time' functions available as stelactions - e.g. actionPrevious_March_Equinox, actionCurrent_June_Solstice, actionNext_December_Solstice, etc.

What do these functions do? When I call them with POST api/stelaction/do, and pass the stelaction id, it doesn't appear to do anything and nothing is returned in the http response.

I presumed from the names that these stelactions would set the time to the corresponding events but that doesn't seem to happen. What is supposed to happen when these stelactions are called?

[alex-w]

Go to the specific moments of the time :)

For example calling action actionCurrent_June_Solstice will set the time of summer solstice (northern hemisphere) in current year.

[alex-w]

Oops... this is effect for application of the error code which is used as "invalid" value of time.

P.S. I didn't checked the code, but value -1000 is very specific for RTS time feature

[alex-w]

I was wrong. The algorithm for calculation of solstices and equinoxes has valid range of application between years -1000 and 3000. So, this is not a bug, this is a feature.

[DrRichardDaystrom]

Interesting. But the VSOP87 planetary theory is good back to -4000 … right? So if I track the Sun to find the solstices / equinoxes, the results should be accurate - even before -1000?

[alex-w]

Interesting. But the VSOP87 planetary theory is good back to -4000 … right? So if I track the Sun to find the solstices / equinoxes, the results should be accurate - even before -1000?

We use Meeus' quick algorithms for finding the time of equinoxes and solstices. Of course you can show equator and ecliptic and finding extremums by hands via VSOP87/DE4xx.

[DrRichardDaystrom]

I’ll give that a try. Thanks.