This site renders images of celestial bodies within our solar system. The simulator software looks up the positions of the Sun, planets and satellites from ephemeris files developed at the Jet Propulsion Lab (JPL), as well as star positions and colors from a variety of stellar databases, and uses special-purpose renderers to draw a color scene. Texture maps for each of the planets and physical models ... Full description.

At this site you can view either a map of the Earth showing the day and night regions at this moment, or view the Earth from the Sun, the Moon, the night side of the Earth, above any location on the planet specified by latitude, longitude and altitude, from a satellite in Earth orbit, or above various cities around the globe. Images can be generated based on a full-colour image of the Earth by day ... Full description.

This is the homepage of the National Aeronautics and Space Administration's (NASA) Science Mission Directorate (SMD). Materials here explain SMD's research, education/outreach efforts, and missions to examine Earth, the Sun, our solar system, and the universe at large. There are links to science strategy douments for NASA's missions, opportunities for scientists and engineers, and to news articles. ... Full description.

This site is the archive for the NASA (National Aeronautic Space Administration) Astronomy Picture of the Day. Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. The archive has photos listed by the day they were featured, by topic, or available through a text search. Full description.

The United States Naval Observatory (USNO) data services page provides tools for calculating the times of sunrise, sunset, moonrise, moonset, and civil twilight, as well as rise and set times for major solar system objects and bright stars. There is a section of lunar data that includes dates of its primary phases, a tool for calculating the illuminated fraction, and a graphic that displays the apparent ... Full description.

This website is a planetarium with simulations intended to predict planetary motions. It is designed to be used in the classroom, or in the lab by students. It demonstrates the following simulations: Mercury/sun; The 'visible' Solar System; World Horizon; Earth/Moon System; Ptolemy/Tycho/Copernicus Solar System Models; Jovian System. This is an ongoing process, so pages are added and modified continuously. ... Full description.

The Astronomical Applications Department of the United States Naval Observatory (USNO) provides access to astronomical data, including sun- and moonrise and set times, moon phases, solar and lunar eclipses, seasons, positions of solar system objects, and others. The publications page provides access to annual astronomical and navigational almanacs, USNO special publications, USNO technical reports, ... Full description.

This program calculates an estimated time of arrival for various destinations in the Universe (for example, the planet Saturn). Visitor input a value for the speed they are traveling away from Earth, and have the option of selecting the units of speed. Full description.

This program simulates the collision of an asteroid or a comet with any planet in Solar System. Users can pick one of the nine planets in the Solar System or the Earth's Moon, choose the composition and diameter (size) of the projectile, and choose the speed of the projectile. Approximate results are returned. Full description.

The National Aeronautics and Space Administration home page provides information on current events at NASA, general information about NASA, and links to a plethora of NASA web sites, educational resources, and NASA Centers. Full description.