astrolibR: Astronomy Users Library

Several dozen low-level utilities and codes from the Interactive Data Language (IDL) Astronomy Users Library ( are implemented in R. They treat: time, coordinate and proper motion transformations; terrestrial precession and nutation, atmospheric refraction and aberration, barycentric corrections, and related effects; utilities for astrometry, photometry, and spectroscopy; and utilities for planetary, stellar, Galactic, and extragalactic science.

AuthorArnab Chakraborty and Eric D. Feigelson
Date of publication2014-08-09 00:14:43
MaintainerEric D. Feigelson <>

View on CRAN

Man pages

adstring: Return RA and Dec as character string(s) in sexigesimal...

airtovac: Convert air wavelengths to vacuum wavelengths

aitoff: Convert longitude, latitude to X,Y using an AITOFF projection

altaz2hadec: Convert horizon (Alt-Az) coordinates to hour angle and...

astrolibR-package: astrolibR: Astronomy Users Library

baryvel: Calculates heliocentric and barycentric velocity components...

bprecess: Precess celestial positions from J2000.0 (FK5) to B1950.0...

calz_unred: Deredden a galaxy spectrum using the Calzetti et al. (2000)...

ccm_unred: Deredden a flux vector using the Cardelli et al. (1989)...

cirrange: Force an angle into the range 0 <= ang < 360

co_aberration: Calculate changes to right ascension and declination due to...

co_nutate: Calculate changes in right ascension and declination due to...

co_refract: Calculate correction to altitude due to atmospheric...

co_refract_forward: Calculate the true altitude of a celestial object from an...

cosmo_param: Derive full set of cosmological density parameters from a...

ct2lst: Convert from Local Civil Time to Local Mean Sidereal Time

daycnv: Convert Julian dates to Gregorian calendar dates

deredd: Deredden stellar Stromgren parameters given for a value of...

dtdz: Integrand for cosmic age vs. redshift in standard cosmology

eci2geo: Convert Earth-centered inertial coordinates to geographic...

eq2hor: Convert celestial (ra-dec) coords to local horizon coords...

eqpole: Convert Right Ascension and declination to X,Y using an...

euler: Transform between Galactic, celestial, and ecliptic...

flux2mag: Convert from flux (ergs/s/cm^2/A) to astronomical magnitudes

fm_unred: Deredden a flux vector using the Fitzpatrick (1999)...

galage: Determine the age of a galaxy given its redshift and a...

gal_uvw: Calculate the Galactic space velocity (U,V,W) of a star

gcirc: Computes rigorous great circle arc distances between points...

geo2eci: Convert geographic spherical coordinates to Earth-centered...

geo2geodetic: Convert from geographic/planetographic to geodetic...

geodetic2geo: Convert from geodetic (or planetodetic) to geographic...

glactc: Convert between celestial and Galactic (or Supergalactic)...

glactc_pm: Convert between celestial and Galactic (or Supergalactic)...

hadec2altaz: Convert Hour Angle and Declination to Horizon (alt-az)...

helio: Compute (low-precision) heliocentric coordinates for the...

helio_jd: Convert geocentric (reduced) Julian date to heliocentric...

helio_rv: Calculate the heliocentric radial velocity of a spectroscopic...

hor2eq: Converts local horizon coordinates (alt-az) to equatorial...

imf: Compute an N-component power-law logarithmic stellar initial...

intdiv: Integer divide

ismeuv: Compute the continuum interstellar extreme ultraviolet (EUV)...

jdcnv: Convert Gregorian dates to Julian days

jprecess: Precess celestial positions from B1950.0 (FK4) to J2000.0...

juldate: Convert from calendar to Reduced Julian Date

ldist: Integrand for luminosity distance calculation

lsf_rotate: Create a 1-d convolution kernel to broaden a spectrum from a...

lumdist: Calculate luminosity distance (in Mpc) of an object given its...

mag2flux: Convert from astronomical magnitudes to flux (ergs/s/cm^2/A)

month_cnv: Convert between a month name and the equivalent number

moonpos: Compute the Right Ascension and Declination of the Moon at...

mphase: Calculate the illuminated fraction of the Moon at given...

nutate: Calculate the nutation in longitude and obliquity for a given...

planck: Calculate the Planck function in units of ergs/cm2/s/A

planet_coords: Calculate low precision Right Ascension and declination for...

polyidl: Calculate polynomial

posang: Compute position angle of source 2 relative to source 1

precess: Precess coordinates from EQUINOX1 to EQUINOX2

precess_xyz: Precess equatorial geocentric rectangular coordinates

premat: Return the precession matrix needed to go from EQUINOX1 to...

radec: Convert Right Ascension and declination from decimal to...

rhotheta: Calculate the separation and position angle of a binary star

sixty: Convert a decimal number to sexigesimal

sphdist: Distance on a sphere

sunpos: Compute the Right Ascension and Declination of the Sun at...

ten: Convert a sexigesimal number or string to decimal

uvbybeta: Derive dereddened colors, metallicity, and Teff from...

vactoair: Convert vacuum wavelengths to air wavelengths

xyz: Calculate geocentric X,Y, and Z and velocity coordinates of...

ydn2md: Convert from year and day number of year to month and day of...

ymd2dn: Convert from year, month, day to day number of year

zang: Determine the angular size of an object as a function of...


adstring Man page
airtovac Man page
aitoff Man page
altaz2hadec Man page
astrolibR Man page
astrolibR-package Man page
baryvel Man page
bprecess Man page
calz_unred Man page
ccm_unred Man page
cirrange Man page
co_aberration Man page
co_nutate Man page
co_refract Man page
co_refract_forward Man page
cosmo_param Man page
ct2lst Man page
daycnv Man page
deredd Man page
dtdz Man page
eci2geo Man page
eq2hor Man page
eqpole Man page
euler Man page
flux2mag Man page
fm_unred Man page
galage Man page
gal_uvw Man page
gcirc Man page
geo2eci Man page
geo2geodetic Man page
geodetic2geo Man page
glactc Man page
glactc_pm Man page
hadec2altaz Man page
helio Man page
helio_jd Man page
helio_rv Man page
hor2eq Man page
imf Man page
intdiv Man page
ismeuv Man page
jdcnv Man page
jprecess Man page
juldate Man page
ldist Man page
lsf_rotate Man page
lumdist Man page
mag2flux Man page
month_cnv Man page
moonpos Man page
mphase Man page
nutate Man page
planck Man page
planet_coords Man page
polyidl Man page
posang Man page
precess Man page
precess_xyz Man page
premat Man page
radec Man page
rhotheta Man page
sixty Man page
sphdist Man page
sunpos Man page
ten Man page
uvbybeta Man page
vactoair Man page
xyz Man page
ydn2md Man page
ymd2dn Man page
zang Man page


astrolibR/R/geo2geodetic.R astrolibR/R/planet_coords.R astrolibR/R/helio.R astrolibR/R/juldate.R astrolibR/R/calz_unred.R astrolibR/R/bprecess.R astrolibR/R/airtovac.R astrolibR/R/uvbybeta.R astrolibR/R/baryvel.R astrolibR/R/hadec2altaz.R astrolibR/R/co_nutate.R astrolibR/R/helio_rv.R astrolibR/R/ldist.R astrolibR/R/eqpole.R astrolibR/R/jprecess.R astrolibR/R/zang.R astrolibR/R/posang.R astrolibR/R/cirrange.R astrolibR/R/premat.R astrolibR/R/polyidl.R astrolibR/R/precess.R astrolibR/R/aitoff.R astrolibR/R/jdcnv.R astrolibR/R/intdiv.R astrolibR/R/hor2eq.R astrolibR/R/sunpos.R astrolibR/R/euler.R astrolibR/R/eci2geo.R astrolibR/R/xyz.R astrolibR/R/geo2eci.R astrolibR/R/co_refract_forward.R astrolibR/R/lumdist.R astrolibR/R/glactc_pm.R astrolibR/R/helio_jd.R astrolibR/R/galage.R astrolibR/R/eq2hor.R astrolibR/R/precess_xyz.R astrolibR/R/sphdist.R astrolibR/R/rhotheta.R astrolibR/R/ccm_unred.R astrolibR/R/ydn2md.R astrolibR/R/ct2lst.R astrolibR/R/ten.R astrolibR/R/altaz2hadec.R astrolibR/R/ismeuv.R astrolibR/R/mag2flux.R astrolibR/R/vactoair.R astrolibR/R/imf.R astrolibR/R/deredd.R astrolibR/R/cosmo_param.R astrolibR/R/sixty.R astrolibR/R/lsf_rotate.R astrolibR/R/geodetic2geo.R astrolibR/R/co_refract.R astrolibR/R/flux2mag.R astrolibR/R/moonpos.R astrolibR/R/gal_uvw.R astrolibR/R/daycnv.R astrolibR/R/radec.R astrolibR/R/planck.R astrolibR/R/nutate.R astrolibR/R/month_cnv.R astrolibR/R/ymd2dn.R astrolibR/R/fm_unred.R astrolibR/R/glactc.R astrolibR/R/co_aberration.R astrolibR/R/mphase.R astrolibR/R/gcirc.R astrolibR/R/dtdz.R astrolibR/R/adstring.R
astrolibR/man/geo2geodetic.Rd astrolibR/man/flux2mag.Rd astrolibR/man/radec.Rd astrolibR/man/co_refract.Rd astrolibR/man/astrolibR-package.Rd astrolibR/man/glactc.Rd astrolibR/man/lsf_rotate.Rd astrolibR/man/precess.Rd astrolibR/man/gal_uvw.Rd astrolibR/man/glactc_pm.Rd astrolibR/man/galage.Rd astrolibR/man/imf.Rd astrolibR/man/jprecess.Rd astrolibR/man/helio.Rd astrolibR/man/geo2eci.Rd astrolibR/man/eqpole.Rd astrolibR/man/hor2eq.Rd astrolibR/man/ten.Rd astrolibR/man/ymd2dn.Rd astrolibR/man/adstring.Rd astrolibR/man/calz_unred.Rd astrolibR/man/euler.Rd astrolibR/man/helio_jd.Rd astrolibR/man/altaz2hadec.Rd astrolibR/man/cosmo_param.Rd astrolibR/man/nutate.Rd astrolibR/man/planet_coords.Rd astrolibR/man/planck.Rd astrolibR/man/moonpos.Rd astrolibR/man/precess_xyz.Rd astrolibR/man/gcirc.Rd astrolibR/man/lumdist.Rd astrolibR/man/eci2geo.Rd astrolibR/man/baryvel.Rd astrolibR/man/airtovac.Rd astrolibR/man/aitoff.Rd astrolibR/man/jdcnv.Rd astrolibR/man/vactoair.Rd astrolibR/man/mphase.Rd astrolibR/man/helio_rv.Rd astrolibR/man/hadec2altaz.Rd astrolibR/man/polyidl.Rd astrolibR/man/ydn2md.Rd astrolibR/man/ldist.Rd astrolibR/man/cirrange.Rd astrolibR/man/bprecess.Rd astrolibR/man/sixty.Rd astrolibR/man/rhotheta.Rd astrolibR/man/premat.Rd astrolibR/man/uvbybeta.Rd astrolibR/man/intdiv.Rd astrolibR/man/sphdist.Rd astrolibR/man/xyz.Rd astrolibR/man/geodetic2geo.Rd astrolibR/man/ccm_unred.Rd astrolibR/man/month_cnv.Rd astrolibR/man/zang.Rd astrolibR/man/eq2hor.Rd astrolibR/man/ct2lst.Rd astrolibR/man/daycnv.Rd astrolibR/man/sunpos.Rd astrolibR/man/mag2flux.Rd astrolibR/man/deredd.Rd astrolibR/man/ismeuv.Rd astrolibR/man/co_aberration.Rd astrolibR/man/dtdz.Rd astrolibR/man/juldate.Rd astrolibR/man/fm_unred.Rd astrolibR/man/posang.Rd astrolibR/man/co_nutate.Rd astrolibR/man/co_refract_forward.Rd

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