The Astronomical Almanac
The Astronomical Almanac contains a wide variety of both technical and
general astronomical information. The book is a worldwide resource for
fundamental astronomical data. It is a joint publication of the U.S. Nautical
Almanac Office at the U.S. Naval Observatory and His Majesty's Nautical Almanac
Office in the UK, and contains data supplied by many
scientists and institutions
from around the world.
The history
of The Astronomical Almanac is found here.
The material appears in sections, each section addressing a specific
astronomical category. The book also includes references to the material,
explanations, and examples. It is available one year in advance of its date.
Contents of
The Astronomical Almanac:
- Section A: PHENOMENA
information on the seasons, phases of the
Moon, configurations of the planets, eclipses, transits of Mercury or Venus,
sunrise/set, moonrise/set times, and times for twilight. Preprints of many of
these data appear in Astronomical
Phenomena.
- Section B: TIME-SCALES AND COORDINATE SYSTEMS
calendar
information, relationships between time scales, universal and sidereal times,
Earth rotation angle, definitions of the various celestial coordinate systems,
frame bias, precession, nutation, obliquity, intermediate system, the position
and velocity of the Earth, and coordinates of Polaris. Preprints of many of
these data appear in Astronomical
Phenomena.
- Section C: SUN
detailed positional information on the Sun,
including the ecliptic and equatorial coordinates, physical ephemerides,
geocentric rectangular coordinates, times of transit, and the equation of
time.
- Section D: MOON
detailed positional information on the Moon
including phases, mean elements of the orbit and rotation, lengths of mean
months, ecliptic and equatorial coordinates, librations, and physical
ephemerides.
- Section E: PLANETS
detailed positional information on each
of the major planets including osculating orbital elements, heliocentric
ecliptic and geocentric equatorial coordinates, and physical ephemerides.
- Section F: NATURAL SATELLITES
orbital
and physical
data as well as ephemerides and phenemona of the satellites of Mars, Jupiter, Saturn
(including the rings), Uranus, Neptune, and Pluto.
- Section G: DWARF PLANETS AND SMALL SOLAR SYSTEM BODIES
positional
and physical data on selected dwarf planets, positional information on bright
minor planets and periodic comets.
- Section H: STARS AND STELLAR SYSTEMS
mean places for
bright stars,
double stars, UBVRI standards, ubvy and H β standards,
spectrophotometric standards, radial velocity standards, variable stars,
exoplanet and host stars, bright galaxies, open clusters, globular clusters,
ICRF2 radio source positions, radio flux calibrators, x-ray sources, quasars,
pulsars, and gamma ray sources.
- Section J:
A placeholder for new material under consideration for future editions of the almanac.
- Section K: TABLES AND DATA
Julian dates,
selected astronomical
constants, relations between time scales, coordinates of the celestial pole,
reduction of terrestrial coordinates, interpolations methods, vectors and
matrices.
- Section L: NOTES AND REFERENCES
notes on the data and references
for source material found in the volume.
- Section M: GLOSSARY
terms and definitions for many of the words
and phrases.
- Section N: INDEX
- Errata:
Page iv of each edition contains newly-discovered
errata. Up-to-date errata for current editions are given here:
2018,
2019,
2020,
2021.
Some links of
interest for The Astronomical Almanac:
