ASCOM Library
Novas Class
NOVAS31: Class presenting the contents of the USNO NOVAS 3.1 library.
NOVAS was developed by the Astronomical Applications department of the United States Naval
Observatory.
Definition
Namespace: ASCOM.Tools.Novas31
Assembly: ASCOM.AstrometryTools (in ASCOM.AstrometryTools.dll) Version: 2.2.1+77356f79b05b579f6d860a4edd5934fda9fe29e4
Assembly: ASCOM.AstrometryTools (in ASCOM.AstrometryTools.dll) Version: 2.2.1+77356f79b05b579f6d860a4edd5934fda9fe29e4
C#
public class NovasVB
Public Class Novas- Inheritance
- Object Novas
Remarks
If you wish to explore or utilise NOVAS3.1 please see USNO's extensive help document "NOVAS 3.1 Users Guide"
(NOVAS C3.1 Guide.pdf) included in the ASCOM Platform Docs start menu folder. The latest revision is also available on the USNO web site at
http://www.usno.navy.mil/USNO/astronomical-applications/software-products/novas
in the "C Edition of NOVAS" link.
Constructors
| Novas | Initializes a new instance of the Novas class |
Methods
| Aberration | Corrects position vector for aberration of light. Algorithm includes relativistic terms. |
| AppPlanet | Compute the apparent place of a planet or other solar system body. |
| AppStar | Computes the apparent place of a star at date 'JdTt', given its catalog mean place, proper motion, parallax, and radial velocity. |
| AstroPlanet | Compute the astrometric place of a planet or other solar system body. |
| AstroStar | Computes the astrometric place of a star at date 'JdTt', given its catalog mean place, proper motion, parallax, and radial velocity. |
| Bary2Obs | Move the origin of coordinates from the barycenter of the solar system to the observer (or the geocenter); i.e., this function accounts for parallax (annual+geocentric or justannual). |
| CalDate | This function will compute a date on the Gregorian calendar given the Julian date. |
| Cel2Ter | This function rotates a vector from the celestial to the terrestrial system. Specifically, it transforms a vector in the GCRS (a local space-fixed system) to the ITRS (a rotating earth-fixed system) by applying rotations for the GCRS-to-dynamical frame tie, precession, nutation, Earth rotation, and polar motion. |
| CelPole | This function allows for the specification of celestial pole offsets for high-precision applications. Each set of offsets is a correction to the modeled position of the pole for a specific date, derived from observations and published by the IERS. |
| CioArray | Calaculate an array of CIO RA values around a given date |
| CioBasis | Compute the orthonormal basis vectors of the celestial intermediate system. |
| CioLocation | Returns the location of the celestial intermediate origin (CIO) for a given Julian date, as a right ascension |
| CioRa | Computes the true right ascension of the celestial intermediate origin (CIO) at a given TT Julian date. This is -(equation of the origins). |
| CleanEph | Close all open ephemeris files and release allocated memory. |
| DLight | Returns the difference in light-time, for a star, between the barycenter of the solar system and the observer (or the geocenter). |
| Ecl2EquVec | Converts an ecliptic position vector to an equatorial position vector. |
| EeCt | Compute the "complementary terms" of the equation of the equinoxes consistent with IAU 2000 resolutions. |
| EphemClose | Close the current ephemeris file |
| Ephemeris | Retrieves the position and velocity of a solar system body from a fundamental ephemeris. |
| EphemOpen | Open the supplied ephemeris file. |
| Equ2Ecl | To convert right ascension and declination to ecliptic longitude and latitude. |
| Equ2EclVec | Converts an equatorial position vector to an ecliptic position vector. |
| Equ2Gal | Converts ICRS right ascension and declination to galactic longitude and latitude. |
| Equ2Hor | Transforms topocentric right ascension and declination to zenith distance and azimuth. |
| Era | Returns the value of the Earth Rotation Angle (theta) for a given UT1 Julian date. |
| ETilt | Computes quantities related to the orientation of the Earth's rotation axis at Julian date 'JdTdb'. |
| FrameTie | To transform a vector from the dynamical reference system to the International Celestial Reference System (ICRS), or vice versa. |
| FundArgs | To compute the fundamental arguments (mean elements) of the Sun and Moon. |
| Gcrs2Equ | Converts GCRS right ascension and declination to coordinates with respect to the equator of date (mean or true). |
| GeoPosVel | This function computes the geocentric position and velocity of an observer on the surface of the earth or on a near-earth spacecraft. |
| GravDef | Computes the total gravitational deflection of light for the observed object due to the major gravitating bodies in the solar system. |
| GravVec | Corrects position vector for the deflection of light in the gravitational field of an arbitrary body. |
| IraEquinox | Compute the intermediate right ascension of the equinox at the input Julian date |
| JulianDate | Compute the Julian date for a given calendar date (year, month, day, hour). |
| LightTime | Computes the geocentric position of a solar system body, as antedated for light-time. |
| LimbAngle | Determines the angle of an object above or below the Earth's limb (horizon). |
| LocalPlanet | Computes the local place of a solar system body. |
| LocalStar | Computes the local place of a star at date 'JdTt', given its catalog mean place, proper motion, parallax, and radial velocity. |
| MakeCatEntry | Create a structure of type 'cat_entry' containing catalog data for a star or "star-like" object. |
| MakeInSpace | Makes a structure of type 'InSpace' - specifying the position and velocity of an observer situated on a near-Earth spacecraft. |
| MakeObject | Makes a structure of type 'object' - specifying a celestial object - based on the input parameters. |
| MakeObserver | Makes a structure of type 'observer' - specifying the location of the observer. |
| MakeObserverAtGeocenter | Makes a structure of type 'observer' specifying an observer at the geocenter. |
| MakeObserverInSpace | Makes a structure of type 'observer' specifying the position and velocity of an observer situated on a near-Earth spacecraft. |
| MakeObserverOnSurface | Makes a structure of type 'observer' specifying the location of and weather for an observer on the surface of the Earth. |
| MakeOnSurface | Makes a structure of type 'on_surface' - specifying the location of and weather for an observer on the surface of the Earth. |
| MeanObliq | Compute the mean obliquity of the ecliptic. |
| MeanStar | Computes the ICRS position of a star, given its apparent place at date 'JdTt'. Proper motion, parallax and radial velocity are assumed to be zero. |
| NormAng | Normalize angle into the range 0 <= angle < (2 * pi). |
| Nutation | Nutates equatorial rectangular coordinates from mean equator and equinox of epoch to true equator and equinox of epoch. |
| NutationAngles | Returns the values for nutation in longitude and nutation in obliquity for a given TDB Julian date. |
| Place | Computes the apparent direction of a star or solar system body at a specified time and in a specified coordinate system. |
| PlanetEphemeris | Get position and velocity of target with respect to the centre object. |
| Precession | Precesses equatorial rectangular coordinates from one epoch to another. |
| ProperMotion | Applies proper motion, including foreshortening effects, to a star's position. |
| RaDec2Vector | Converts equatorial spherical coordinates to a vector (equatorial rectangular coordinates). |
| RadVel | Predicts the radial velocity of the observed object as it would be measured by spectroscopic means. |
| ReadEph | Produces the Cartesian heliocentric equatorial coordinates of the asteroid for the J2000.0 epoch coordinate system from a set of Chebyshev polynomials read from a file. |
| Refract | Computes atmospheric refraction in zenith distance. |
| SetLogger | Assign a logger instance to the NOVAS component |
| SiderealTime | Computes the Greenwich sidereal time, either mean or apparent, at Julian date 'JdHigh' + 'JdLow'. |
| SolarSystem | Interface between the JPL direct-access solar system ephemerides and NOVAS-C. |
| Spin | Transforms a vector from one coordinate system to another with same origin and axes rotated about the z-axis. |
| StarVectors | Converts angular quantities for stars to vectors. |
| State | Read and interpolate the JPL planetary ephemeris file. |
| Tdb2Tt | Computes the Terrestrial Time (TT) or Terrestrial Dynamical Time (TDT) Julian date corresponding to a Barycentric Dynamical Time (TDB) Julian date. |
| Ter2Cel | This function rotates a vector from the terrestrial to the celestial system. |
| Terra | Computes the position and velocity vectors of a terrestrial observer with respect to the center of the Earth. |
| TopoPlanet | Computes the topocentric place of a solar system body. |
| TopoStar | Computes the topocentric place of a star at date 'JdTt', given its catalog mean place, proper motion, parallax, and radial velocity. |
| TransformCat | To transform a star's catalog quantities for a change of epoch and/or equator and equinox. |
| TransformHip | Convert Hipparcos catalog data at epoch J1991.25 to epoch J2000.0, for use within NOVAS. |
| Vector2RaDec | Converts a vector in equatorial rectangular coordinates to equatorial spherical coordinates. |
| VirtualPlanet | Compute the virtual place of a planet or other solar system body. |
| VirtualStar | Computes the virtual place of a star at date 'JdTt', given its catalog mean place, proper motion, parallax, and radial velocity. |
| Wobble | Corrects a vector in the ITRF (rotating Earth-fixed system) for polar motion, and also corrects the longitude origin (by a tiny amount) to the Terrestrial Intermediate Origin (TIO). |