Celestia is a 3-D astronomy program created by Chris Laurel. The program is based on the Hipparcos Catalogue and allows users to travel through an extensive universe, modeled after reality at any speed, in any direction and at any time in history. Celestia displays and interacts with objects ranging in scale from artificial satellites to entire galaxies in three dimensions using OpenGL, from perspectives which would not be possible from a classic planetarium or other ground based display. Celestia is a free astronomy computer program. ... For other uses, see Jupiter (disambiguation). ... Apparent magnitude: 5. ... Atmosphere Surface pressure: trace Composition: 90% sulfur dioxide Io (eye-oe, IPA: , Greek Ῑώ) is the innermost of the four Galilean moons of Jupiter and, with a diameter of 3,642 kilometers, is the fourth largest moon in the Solar System. ... For other uses, see Software developer (disambiguation). ... Code complete redirects here. ... is the 114th day of the year (115th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance to the Gregorian calendar. ... An operating system (OS) is a software that manages computer resources and provides programmers with an interface used to access those resources. ... A cross-platform (or platform independent) programming language, software application or hardware device works on more than one system platform (e. ... Educational software is computer software whose primary purpose is teaching or self-learning. ... A software license is a legal agreement which may take the form of a proprietary or gratuitous license as well as a memorandum of contract between a producer and a user of computer software. ... GPL redirects here. ... A website (alternatively, web site or Web site) is a collection of Web pages, images, videos or other digital assets that is hosted on one or more web servers, usually accessible via the Internet. ... For other uses, see Astronomy (disambiguation). ... The Hipparcos and Tycho Catalogues (Tycho-1) are the primary products of the European Space Agencys astrometric mission, Hipparcos. ... This article is about artificial satellites. ... For other uses, see Galaxy (disambiguation). ... OpenGL (Open Graphics Library) is a standard specification defining a cross-language cross-platform API for writing applications that produce 2D and 3D computer graphics. ... For the song by Ai Otsuka, see Planetarium (song) // A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. ...

NASA and ESA have used Celestia in their educational^[1] and outreach programs,^[2] as well as for interfacing to trajectory analysis software.^[3] For other uses, see NASA (disambiguation). ... ESA redirects here. ...

Celestia is available for Linux, Mac OS X, and Microsoft Windows. Released under the GNU General Public License, Celestia is free software. This article is about operating systems that use the Linux kernel. ... Mac OS X (pronounced ) is a line of graphical operating systems developed, marketed, and sold by Apple Inc. ... Windows redirects here. ... GPL redirects here. ... Free software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with minimal restrictions only to ensure that further recipients can also do these things. ...

Functions

Typical DSO survey in Celestia

Celestia displays the Hipparcos Catalogue (HIP) of almost 120,000 stars. Celestia uses the very accurate VSOP87 theory of planetary orbits. This makes it possible for it to provide a Solar and lunar eclipse finder and to display the orbital paths of planets (including extrasolar planets), moons, asteroids, comets, artificial satellites, and spacecrafts. The user can vary the number of stars that are visible on the screen and have them drawn in different styles. Deep sky is a term used by amateur astronomers to describe mostly faint objects outside the solar system like star clusters, nebulae and galaxies; compare with deep space. These objects are hundreds to billions of light years distant. ... The Hipparcos and Tycho Catalogues (Tycho-1) are the primary products of the European Space Agencys astrometric mission, Hipparcos. ... The Secular Variations of the Planetary Orbits (French: Variations Séculaires des Orbites Planétaires, abbreviated as VSOP) is a theory describing the long-term changes (secular variation) in the orbits of the planets Mercury to Neptune to the highest accuracy astronomy can muster nowadays. ... Photo taken during the 1999 eclipse. ... Time lapse movie of the 3 March 2007 lunar eclipse A lunar eclipse occurs whenever the Moon passes through some portion of the Earth’s shadow. ... This article is about the astronomical term. ... An extrasolar planet, or exoplanet, is a planet beyond the Solar System. ... A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called the primary. ... For other uses, see Asteroid (disambiguation). ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... This article is about artificial satellites. ... The Space Shuttle Discovery as seen from the International Space Station. ...

Celestia users can travel/fly through the Celestia universe using simple keyboard controls, at any speed from 0.001m/s to millions of light years/s. Viewpoints can be set to look forward, backward or at any angle to direction of travel. Controls allow users to orbit stars, planets, moons and other space objects, track space objects such as spacecraft, asteroids and comets as they fly by, or travel to and/or fly through nebula and irregular, elliptical and spiral galaxies (over 10,000 galaxies included).

The time simulated by Celestia can be set at any point in the future or past, although planetary orbits are only accurate within a few thousand years of the present day, and date arithmetic overflows at the year 5874774.

The names and positions of multitudes of objects in space can be displayed, from galaxies, star clusters, nebula, constellations and stars to planets, moons, asteroids, comets and artificial satellites, as well as the names and locations of cities, craters, observatories, valleys, landing sites, continents, mountains, seas and other surface features. This article or section does not cite its references or sources. ... This article is about the astronomical object. ... This article is about scientific observatories. ... Fljótsdalur in East Iceland, a rather flat valley In geology, a valley (also called a vale or dale) is a depression with predominant extent in one direction. ... Animated, colour-coded map showing the various continents. ... For other uses, see Mountain (disambiguation). ... This article is about the body of water. ...

Celestia displays such features as detailed atmospheres on planets and moons, sunsets and sunrises, moving clouds, planetary rings, eclipse and ring shadows, constellation lines, borders and illustrations, night-side lights, detailed surface textures, nebula gases and star flares.

Information about the objects that Celestia draws can also be displayed: the radius, the distance, length of the sidereal day and average temperature of the planets are shown and the distance, luminosity relative to the sun, spectral class, surface temperature and radius of stars are indicated.

The user can change Celestia's field of view from as wide as 120 degrees to a highly magnifying 3.4 seconds of arc, while dividing the window into multiple panes, in order to observe several objects at the same time and including Light time delay if desired. Light-time correction is a slight angular shift in the apparent position of a celestial object, especially a planet, from its geometric position on the celestial sphere caused by the objects motion during the time it takes its light to reach Earth. ...

Graphic screen-shots and movies can be captured in classic or HD resolutions (up to 1920x1080) on Windows and Linux platforms.

Celestia's support for game pads and joysticks is relatively limited, employing many keyboard shortcuts instead.

Celestia can be extended with new objects and there are hundreds of third-party, user-created add-ons available for installation, both fictional and realistic. The extension mechanism uses Lua as its built-in scripting language. Educational lessons and computer lesson plans are available. In computing, the Lua (pronounced LOO-ah) programming language is a lightweight, reflective, imperative and procedural language, designed as a scripting language with extensible semantics as a primary goal. ...

Limitations

The default setting for Celestia's Earth is a spheroid. The irregular surface of the Earth causes low Earth orbit satellites to seem to be in the wrong places in the sky when watched from Celestia's ground, even when the Earth's oblateness is specified. This article is about Earth as a planet. ... In mathematics, a spheroid is a quadric surface in three dimensions obtained by rotating an ellipse about one of its principal axes. ... A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350 - 1400 km above the Earths surface. ... The flattening, ellipticity, or oblateness of an oblate spheroid is the relative difference between its equatorial radius a and its polar radius b: The flattening of the Earth is 1:298. ...

Many types of astronomical objects are not included with Celestia. Variable stars, supernovae, black holes and nebulae are missing from the standard distribution. Some are available as add-ons. Although objects which form part of a planetary system move, and stars rotate about their axes and orbit each other in multiple star systems, stellar proper motion is not simulated and galaxies are at fixed locations. Celestia's binary star catalogs only describe a few hundred systems of multiple stars. Most binary star systems cannot be simulated because adequate orbital information is not yet available. This article or section contains a plot summary that is overly long or excessively detailed. ... For other uses, see Supernova (disambiguation). ... For other uses, see Black hole (disambiguation). ... The Triangulum Emission Nebula NGC 604 The Pillars of Creation from the Eagle Nebula For other uses, see Nebula (disambiguation). ... An artists concept of a planetary system A planetary system consists of the various non-stellar objects orbiting a star such as planets, moons, asteroids, meteoroids, comets, and cosmic dust. ... The proper motion of a star is the motion of the position of the star in the sky (the change in direction in which we see it, as opposed to the radial velocity) after eliminating the improper motions of the stars, which affect their measured coordinates but are not real... For other uses, see Galaxy (disambiguation). ... For the band, see Binary Star (band). ...

Celestia does not include any stars which are more than about 16,000 light-years from the Sun. That is as far as the Hipparcos astrometric satellite could accurately measure distances. Celestia's 128 bit mathematical operations also cause accuracy problems when drawing stars more distant than that. In addition, objects in solar systems are only drawn to a distance of one light-year from their suns. A light-year, symbol ly, is the distance light travels in one year: exactly 9. ...

Add-ons

A very high-resolution texture of the planet Mars

A very high-resolution texture of the Moon, including a normal map

About 15 gigabytes of extensions are available in addition to the base program, produced by an active user community.^[4] Image File history File linksMetadata Download high-resolution version (1280x1024, 866 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Celestia User:TAnthony/images Metadata This file contains additional information, probably added from the digital camera or scanner... Image File history File linksMetadata Download high-resolution version (1280x1024, 866 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Celestia User:TAnthony/images Metadata This file contains additional information, probably added from the digital camera or scanner... This article is about the astronomical term. ... Adjectives: Martian Atmosphere Surface pressure: 0. ... Image File history File links Download high-resolution version (1280x978, 913 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Celestia ... Image File history File links Download high-resolution version (1280x978, 913 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Celestia ... This article is about Earths moon. ... This article is about the unit of measurement. ...

High resolution surface textures are available for most solar system bodies, including Virtual Textures with complete coverage up to 32768 pixels wide (1.25 km/pixel at the Earth's equator), with selected coverage at higher resolutions. This allows very close views of the Earth, Mars and the Moon. Many 3D models of historical and existing spacecraft are available flying in reasonably accurate trajectories, from Sputnik 1 and Voyager 2 to the Hubble Space Telescope and International Space Station, as are extended data plots for stars (2 million with correct spatial coordinates). DSOs (nebulae, galaxies, open clusters etc), as well as catalogues of thousands of asteroids and comets and more than 96,000 locations on the Earth can be drawn by the program. Add-ons also include extensive space objects such as red and blue supergiants, red and brown dwarfs, neutron stars, spinning pulsars, rotating black holes with accretion disks, protostars, star nursery nebula, supernova and planetary nebula, galactic redshifts, geological planetary displays (e.g. - 3-D interiors, topographic and bathymetric maps, ice age simulations), planetary aurora, rotating magnetic fields, animated solar flares and prominences, 3-D craters and mountains, and historic collision events. All can be visited via the Celestia travel interface. All stages in the life cycle of stars are available, from nebula stage to black dwarf. Sputnik 1 (Russian: , Satellite-1, or literally Co-traveler-1 byname ПС-1 (PS-1, i. ... Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ... The Hubble Space Telescope (HST; also known colloquially as the Hubble or just Hubble) is a space telescope that was carried into Earth orbit by the Space Shuttle in April 1990. ... ISS redirects here. ... Deep sky is a term used by amateur astronomers to describe mostly faint objects outside the solar system like star clusters, nebulae and galaxies; compare with deep space. These objects are hundreds to billions of light years distant. ... Galactic cluster redirects here. ...

Numerous scripts are available; these include simple tours, reconstructions of complex space missions such as Cassini–Huygens and Deep Impact, and scripts showing useful information, like size comparisons, or particular events such as multiple simultaneous eclipses of Jupiter's moons or the evolution of a star. Cassini–Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... Illustration of the Deep Impact space probe after impactor separation (artists conception) Deep Impact is a NASA space probe designed to study the composition of the interior of the comet Tempel 1. ...

Many well known fictional universes are depicted in detail, with whole solar systems and 3D models - films such as 2001: A Space Odyssey, Star Trek and Star Wars, and TV shows including Stargate SG-1 and Babylon 5. Addons illustrating less well known Web fiction, like Orion's Arm, and detailed personal works by members of the Celestia community depicting extensive fictional solar systems with inhabited worlds, spacecraft, cities and exotic special effects can also be obtained. A fictional universe is an imaginary world that serves as the setting or backdrop for one or (more commonly) multiple works of fiction or translatable non-fiction. ... A movie poster from the original release of 2001 2001: A Space Odyssey (1968) is an immensely popular and influential science fiction film and book; the film directed by Stanley Kubrick and the book written by Arthur C. Clarke. ... This article is about the entire Star Trek franchise. ... This article is about the series. ... Stargate SG-1 (often abbreviated as SG-1) is a science fiction television series, part of the Stargate franchise. ... Babylon 5 is an epic American science fiction television series created, produced, and largely written by J. Michael Straczynski. ... Orions Arm (or OA for short) is an online science fiction world-building project, founded by M. Alan Kazlev. ...

The death of Earth 5 billion years from now

Educational add-ons (built by and for educators) are also available and are in use worldwide. These activities provide approximately 40 hours of space journeys and astronomical lessons, to include extensive tours of the Celestia universe, the complete life cycle of stars, the solar system, the human space program, the Search for Extraterrestrial Intelligence (SETI), and depictions of astronomical events such as the formation of our moon billions of years ago, and the possible terraforming of Mars in the future. A special educational version of the Celestia program can also provide sound effects and "cockpit" features to simulate flying in a real hyperdrive spacecraft. Targeting the home user, middle and high school students and beginning courses in collegiate astronomy, they are available in several languages^[5].

In the media

Celestia was used in the media by the CBS television show NCIS (Season 4, Episode 22: In The Dark). Character Timothy McGee explains what Celestia is, and how an add-on can allow the user to store a diary within the program as well. NCIS is an American police procedural television series revolving around a fictional team of special agents from the Naval Criminal Investigative Service of the United States Navy and United States Marine Corps. ... In The Dark is the 92nd episode of the drama television series NCIS. Spoiler warning: An assistant to a blind photographer sees a dead Petty Officer in one of his pictures and they call NCIS to investigate. ...

Similar applications

Similar applications include the free software applications Stellarium and KStars, and the proprietary applications Orbiter, XEphem (both freeware), Starry Night (commercial). WorldWide Telescope, which was launched on May 12, 2008, will also offer features included in Celestia. Stellarium is a free software planetarium, licensed under the terms of the GNU General Public License, available for Linux, Windows and Mac OS X. It uses OpenGL to render a realistic sky in real time. ... Screenshot of KStars showing the night sky from Hanover. ... Proprietary software is software with restrictions on copying and modifying as enforced by the proprietor. ... Orbiter is a closed source freeware space flight simulator for the Windows operating system. ... The term Freeware refers to gratis proprietary software with closed source. ... Starry Night Screen Shot Starry Night is a commercial planetarium software program, available for Windows and Mac OS X. The software makes it possible to view the night sky from any location on Earth, or any position in the local universe, such as the Local Group. ...

Notes

Image File history File links Free_Software_Portal_Logo. ... Image File history File links Portal. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 299th day of the year (300th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 299th day of the year (300th in leap years) in the Gregorian calendar. ... is the 329th day of the year (330th in leap years) in the Gregorian calendar. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 354th day of the year (355th in leap years) in the Gregorian calendar. ...

External links

• Official website
• Official Forum website
• Celestia Motherlode Collection of add-ons made by various people
• Celestia Motherlode educational Resources Celestia Educational page
• Page on Celestia hosted by NASA
• Instance of ESA using Celestia