From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 8 Jul 2015 20:46:52 -0400 Subject: Initial commit --- math/slalib/doc/sla.news | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 math/slalib/doc/sla.news (limited to 'math/slalib/doc/sla.news') diff --git a/math/slalib/doc/sla.news b/math/slalib/doc/sla.news new file mode 100644 index 00000000..541b6c8a --- /dev/null +++ b/math/slalib/doc/sla.news @@ -0,0 +1,36 @@ +SLALIB_Version_2.3-0 Expiry 30 September 1999 + +The latest releases of SLALIB include the following changes: + +* The 1999 January 1 UTC leap second has been added to the DAT routine. + +* Four new routines have been introduced which transform between the + FK5 system and the ICRS (Hipparcos) system. FK52H and H2FK5 transform + star positions and proper motions from FK5 coordinates to Hipparcos + coordinates and vice versa. FK5HZ and HFK5Z do the same but for the + case where the Hipparcos proper motions are zero. + +* Six new routines have been introduced for dealing with orbital elements. + Four of them (sla_EL2UE, sla_PV2UE, sla_UE2EL and sla_UE2PV) provide + applications with direct access to the "universal variables" method + that was already being used internally. Compared with using conventional + (angular) elements and solving Kepler's equation, the universal variables + approach has a number of advantages, including better handling of near- + parabolic orbits and greater efficiency. The remaining two routines + (sla_PERTEL and sla_PERTUE) generate updated elements by applying + major-planet perturbations. The new elements can then be used to + predict positions that are much more accurate. For minor planets, + sub-arcsecond accuracy over a decade is achievable. + +* Several observatory sites have been added to the OBS routine: CFHT, + Keck 2, Gemini North, FCRAO, IRTF and CSO. The coordinates for all + the Mauna Kea sites have been updated in accordance with recent aerial + photography results made available by the Institute for Astronomy, + University of Hawaii. + + P.T.Wallace + 21 April 1999 + + ptw@star.rl.ac.uk + +44-1235-44-5372 +-------------------------------------------------------------------------- -- cgit