Directorate of Time U.S. Naval Obs. What time is it?
Time and Frequency Division National Institute of Standards and Technology (NIST)
Local Sidereal Time Clock
¿ Que hora es ? Hora oficial a Madrid - España ? horlogeparlante

Julian Date converter (USNO)
Date Conversion Utility (HEASARC)
Conversion Between Date and Julian Date (NOAA)
Conversion of Julian Date to Calendar Date and vice versa (Thomas Bak)
Julian Date from Calendar Date Calculator -- Calendar Date from Julian Date Calculator

Seccion de Efemérides del ROA (Real Instituto y Observatorio de la Armada, San Fernando, Cadiz)

Anuario astronómico del OAN (Observatorio Astronómico Nacional, Madrid)

The Institut de Mécanique Céléste et de Calcul des Ephémérides (IMCCE) Bureau des longitudes

Astronomical and Navigational Almanacs (USNO, U.S. Naval Obs., USA) & (HMNAO, HM Nautical Almanac Office, UK)

Her Majesty's Nautical Almanac Office (HMNAO)

Object Observability (Skycalc by John Thorstensen)
Astronomical Sky Calendar (Skycalc by John Thorstensen)

Sunrise/sunset calculator (NRC)

Sky Calendar Tool (ESO) (Sun rise and set times, twilights, etc.)

Sky Calendar (Abrams Planetarium)

Què tal? in the Current Sky

Sky & Telescope, Observing (Sky & Telescope)

SkyEye your guide to this month's celestial events
Interactive Astronomy Pages

Efemérides (ASTRORED)

Efemérides de Astronomía con Applets de Java (Joaquín García Ferrer)

¿Donde está la ISS (Estación Espacial Internacional) ahora mismo? (ASTRORED)
Visibilidad de de la ISS desde Madrid Heavens-Above
NASA SkyWatch when and where the ISS (International Space Station) can be seen

Space Calendar (JPL) NASA

Spacewath space.com

Coordinate conversion From Epoch to Epoch (CoCo program)
Coordinate & Galactic Extinction Calculator (NED)

Viewing dates when object or coordinate is observable from a specified mission

Estimating Limiting Magnitude

The Constellations and their Stars

"The Constellation of the Week" Archives (Richard Dibon-Smith)

The Munich Archive Astromaps (C. Kronberg)

National Geographic's Star Chart (with overlays of HST images)

Star Catalogs in 3D

NASA Solar Eclipse page (Fred Espenak, NASA's GSFC)

NASA Eclipse Home Page (Fred Espenak, NASA's GSFC)

Upcoming Eclipses of the Sun and Moon (U.S. Naval Observatory)

USNO Eclipse Portal global and local visibility of solar and lunar eclipses (U.S. Naval Observatory)
HMNAO Eclipse Portal global and local visibility of solar and lunar eclipses (HM Nautical Almanac Office)

Sky & Telescope Eclipse Page

Working Group on Solar Eclipses of the IAU

Live! Eclipse

Sunrise/Sunset/Twilight and Moonrise/Moonset Calculator for any location if you know the longitude and latitude. (Madrid longitude= -3 41 15, latitude= 40 24 30)

Earth Viewer
Face of the Earth (ARC Science Simulations)
Images of the Earth (National Geographic)
How far is it? (find the latitude and longitude of two places, and then calculates the distance)

Current Phase of the Moon (updated every 4 hours) (U.S. Naval Observatory) Phases of the Moon and Percent of the Moon Illuminated (U.S. Naval Observatory)
Phase of the Moon (updated every 60 seconds) (Lunar Outreach Services)
Current Moon Phase (S&T)
Moon Phases Astronomie.de
Moonlight diagrams for La Palma (ING), and various other observatories.
Moon phases Wise Observatory Astronomical Calendar
Interactive map of the Moon

Solar system simulator NASA/JPL/Caltech

A Guide to the Solar System, (Online University)
Comets and Meteors Showers (Online University)

Jupiter Events
Satelites de Jupiter Astronomie.de
Jupiter's Moons JavaScript (S&T)
Transit Times of Jupiter's Great Red Spot (S&T)

Saturn Events ---- Saturn Moon Tracker
Saturn Ring Plane Crossing Information ---- Saturn Viewer
Saturn's Moons JavaScript (S&T)

Mars: Which Side Is Visible? (S&T)

Astronomía Internacional / International Astronomy

Enviar sugerencias y nuevas direcciones a:
Send suggestions and new links to:

David Montes ... e-mail: webmasterastrax.fis.ucm.es
Javier Gorgas ...