[AstroPy] BCE Time & Dates?

Derek Homeier derek at astro.physik.uni-goettingen.de
Wed Aug 14 13:53:32 EDT 2019


On 14 Aug 2019, at 7:30 pm, Derek Homeier <derek at astro.physik.uni-goettingen.de> wrote:
> 
>> 	>>> t = Time('-4444-10-03T09:00:00')
>> 	Traceback (most recent call last):
> 
> `Time` does support a class of `long*` subformats, which are even automatically recognised,
> but somewhat less than intuitive - they require a sign+5-digit year format!
> 
> t = Time(‘-04444-10-03T09:00:00’)
> 
> should work (at least create a valid Time object. Not sure if there is a logical reason why
> signed 4-digit years cannot be recognised (other than apparently only exactly two year
> formats being defined; so <4 digits are not accepted either). Might be worth filing an issue.

Possibility some justification (as well as discussion of the existence of a “year 0” - i.e.
‘-04444’ is the year 4445 BC!) is found in the corresponding FITS paper:
https://www.aanda.org/articles/aa/abs/2015/02/aa24653-14/aa24653-14.html

Cheers,
					Derek



More information about the AstroPy mailing list