Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-22 Thread Ian Batten
On 21 Aug 2014, at 08:06, Clive D.W. Feather cl...@davros.org wrote: Warner Losh said: Absolutely. We get leap days right because we don?t have to hear from the pope?s astronomers every year to know if it will be a leap year or not. We know for thousands of years. And note that it was

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-22 Thread Preben Nørager
There exist, in use, two differing definitions of the dynamical equinox. The one is called the rotational equinox, and the other is called the inertial equinox (Standish 1981, [ http://adsabs.harvard.edu/full/1981A%26A...101L..17S]). The IERS uses the inertial equinox. I differentiate between

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-21 Thread Clive D.W. Feather
Warner Losh said: Absolutely. We get leap days right because we don?t have to hear from the pope?s astronomers every year to know if it will be a leap year or not. We know for thousands of years. And note that it was exactly that problem that led Caius Julius to reform the calendar in the

[LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Preben Nørager
In the discussion about whether or not to drop the leap second, I think it is not a question about solar time or not solar time. It is in other words not a question about either solar time or atomic time. If we drop the leap second it will be in favour of another timescale, which uses only

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Ask Bjørn Hansen
On Aug 20, 2014, at 18:48, leapsecs-requ...@leapsecond.com wrote: Dropping Leap Seconds is something like burning great libraries. That's a very particular opinion. I'd compare it to adding decimal digits to Pi instead of just saying 3 is accurate enough. :-) Ask -- http://askask.com/

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Brooks Harris
On 2014-08-20 10:23 PM, Warner Losh wrote: On Aug 20, 2014, at 7:40 PM, Brooks Harris bro...@edlmax.com wrote: Since the beginning of civilization society has pursued the goal of perfect timekeeping. UTC is one of the great intellectual achievements of mankind. The difficulties with Leap

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Warner Losh
On Aug 20, 2014, at 8:16 PM, Ask Bjørn Hansen a...@develooper.com wrote: On Aug 20, 2014, at 18:48, leapsecs-requ...@leapsecond.com wrote: Dropping Leap Seconds is something like burning great libraries. That's a very particular opinion. I'd compare it to adding decimal digits to Pi

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Warner Losh
On Aug 20, 2014, at 9:28 PM, Brooks Harris bro...@edlmax.com wrote: On 2014-08-20 10:23 PM, Warner Losh wrote: On Aug 20, 2014, at 7:40 PM, Brooks Harris bro...@edlmax.com wrote: Since the beginning of civilization society has pursued the goal of perfect timekeeping. UTC is one of the

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Rob Seaman
Ask Bjørn Hansen writes: I'd compare it to adding decimal digits to Pi instead of just saying 3 is accurate enough. Warner Losh says: A more proper analogy would be using 3.141593 instead of 3.1415926… Proper analogies, is it? More like 2.7182818 - the functional forms differ. To do

Re: [LEAPSECS] Solar time: From mean solar days, to mean solar years

2014-08-20 Thread Brooks Harris
On 2014-08-20 11:57 PM, Warner Losh wrote: On Aug 20, 2014, at 9:28 PM, Brooks Harris bro...@edlmax.com wrote: On 2014-08-20 10:23 PM, Warner Losh wrote: On Aug 20, 2014, at 7:40 PM, Brooks Harris bro...@edlmax.com wrote: Since the beginning of civilization society has pursued the goal