0.14051   2025-01-11 18:06:06+00:00 Europe/London
====
* moved constants into main module, Astro::Constants
* removed Astro::Constants::CGS from distribution
* removed short names
* changed `:long` tag to `:all`

v0.14	2020 Apr
====
* updated values to the **2018 CODATA** standard
* build script now produces a Raku module for Astro::Constants
* removed references to CGS in documentation
* added script that fetches constant values and uncertainties from NIST
* added warnings to module when using deprecated constants
* added a script to archive the current PhysicalConstants.xml file
* added dimensions to constants in terms of the SI base units
* values that are established by definition are assigned an relative uncertainty of 0
* clarified definition of critical density parameter, rho_c
* updated PhysicalConstants.xml schema definition
  * changed name of **url** element to **source**
  * added _authority_, _year_ and _reference_ attributes to **source**

v0.13	2018 May
====
* adding symbols to PhysicalConstants.xml definition file
* adding deprecation warning to Astro::Constants::CGS - to be removed from package v0.15
* alternateName element in PhysicalConstants.xml can now take a "type" attribute
* alternateName with type=deprecated are now listed with the deprecated tag, not the long tag
* adding RADIUS_JUPITER and MASS_JUPITER to the definition file
* adding notice of deprecation to Astro::Constants::CGS
* updating schema definition to accommodate symbol elements and allow attributes in alternateName
* switched ELECTRON_CHARGE to CHARGE_ELEMENTARY in long name and alternateName

v0.12	2017 Oct
=====
* Fixed MASS_HYDROGEN
* added warning for undefined constants in precision
* removed alternateNames from :long export tag

v0.11	2017 May
=====
* Fixed precision() 

* Added the following constants for compatability with Astro::Cosmology

Added
-----

FOUR_PI 	- 4 * PI
STERADIAN	- solid angle subtended by the radius squared in square degrees

Deprecated
----------

HUBBLE_TIME	- should move to Astro::Cosmology as it's not really constant


v0.10	2016 Feb
=====
A couple of interface-breaking changes:
* 'list_constants' and 'describe_constant' have been removed and
	people are directed to the docs, 'perldoc Astro::Constants'
* 'precision' is broken at the moment and will be fixed in the next version

These changes are enhancements/improvements:
* Short name constants are now *actually* constant and cannot be assigned to
* Values are now stored in an XML file, PhysicalConstants.xml
* Values have been updated using NIST's CODATA 2014 and the IAU 2009/2012
	System of Astronomical Constants
* Long names have an added alternate name to facilitate migrating from
	adjective_noun to noun_adjective.


List of name changes
====================
New names have replaced the old names which are retained in the file using 
the <alternateName> tag

old					new
===					===
LIGHT_SPEED			SPEED_LIGHT
ELECTRON_CHARGE 	CHARGE_ELEMENTARY
A_RAD				DENSITY_RADIATION
VACUUM_IMPEDANCE	IMPEDANCE_VACUUM
HBAR				H_BAR
ELECTRON_MASS		MASS_ELECTRON
PROTON_MASS			MASS_PROTON
NEUTRON_MASS		MASS_NEUTRON
HYDROGEN_MASS		MASS_HYDROGEN
SOLAR_MASS			MASS_SOLAR
SOLAR_RADIUS		RADIUS_SOLAR
SOLAR_LUMINOSITY	LUMINOSITY_SOLAR
EARTH_MASS			MASS_EARTH
EARTH_RADIUS		RADIUS_EARTH
RHO_C				DENSITY_CRITICAL_RHOc
EARTH_MASS			MASS_EARTH
EARTH_RADIUS		RADIUS_EARTH
THOMSON_XSECTION	THOMSON_CROSS_SECTION
ELECTRON_RADIUS		RADIUS_ELECTRON
BOHR_RADIUS			RADIUS_BOHR
SOLAR_TEMPERATURE	TEMPERATURE_SOLAR_SURFACE
CMB_TEMPERATURE		TEMPERATURE_CMB
SOLAR_DENSITY		DENSITY_SOLAR
EARTH_DENSITY		DENSITY_EARTH
SOLAR_GRAVITY		GRAVITY_SOLAR
EARTH_GRAVITY		GRAVITY_EARTH
SOLAR_V_MAG			MAGNITUDE_SOLAR_V
SOLAR_V_ABS_MAG		MAGNITUDE_SOLAR_V_ABSOLUTE
LUNAR_RADIUS		RADIUS_LUNAR
LUNAR_MASS			MASS_LUNAR
LUNAR_SM_AXIS		AXIS_SM_LUNAR
LUNAR_ECCENTRICITY	ECCENTRICITY_LUNAR

These 2 have had new names added, but I'm not sure which I like more
PERMITIV_FREE_SPACE	PERMITIVITY_0
PERMEABL_FREE_SPACE	PERMEABILITY_0

add in new definitions to <category>conversion
YEAR_TROPICAL			365.242 190
YEAR_SIDEREAL			365.256 363
YEAR_ANOMALISTIC		365.259 635
YEAR_ECLIPSE			346.620 073

Candidates for removal
======================

HUBBLE_TIME - this constant is inherited from Jeremy Bailin's Astroconst.
	It is the inverse of the Hubble constant, valued at 100 km/s/Mpc and
	is not constant.  Suggest moving it into Astro::Cosmology

Introduced
==========
MASS_ALPHA	- mass of the alpha particle
