Abstract:
A hand-held electronic celestial object locating device assists in identifying a celestial object or directing a user to a desired celestial object. The device is useful for locating or identifying any celestial object including stars, constellations, planets, comets, asteroids, artificial satellites, and deep sky objects to name a few. The device utilizes sensors for 3-axis magnetic field and 3-axis gravitational field detection. The device utilizes a processor and an electronic database to perform the required calculations. The device&#39;s database may be updated through access to the Internet through which the updates may be purchased.

Description:
This application claims the benefit of U.S. Provisional Application No. 60/122,711, filed Mar. 3, 1999. 
    
    
     BACKGROUND 
     1. Field of Invention 
     This invention relates to astronomy, specifically to an electronic device capable of locating and identifying celestial objects. 
     2. Description of Prior Art 
     People have always been fascinated with the heavens. They have been cited for the origins of the universe and life. Stars and constellations are the basis of fables, myths, and stories in almost every culture on the earth. The stars are used as indicators of peoples&#39; future by some. Sailors and other travelers rely on certain stars and constellations as indicators of position and direction. Further, there is an enormous amount of professional and hobbyist interest in the stars. 
     Both professionals and hobbyists use celestial object identifying devices to locate a star, constellation, planet, comet, asteroid, artificial satellite, deep sky object or other heavenly objects, which shall be referred to collectively as celestial objects. Some existing celestial object identifying devices function by using a combination of mechanical electrical or pre-tabulated charts or tables. 
     U.S. Pat. No. 3,863,365 to Moliard discloses a method which uses a flat spinning disc that contains a pictorial representation of a celestial hemisphere containing constellations and stars. The user must rotate the disc to the current time and date, and then orient themselves with the proper compass direction. Identification of a celestial object is attempted by the user comparing the sky with the celestial hemisphere pictorial representation. This method proves rather difficult to locate a celestial object, in that the sky and the pictorial representation of the celestial hemisphere are two different scales. Additionally, the disc contains a flattened perspective of the celestial hemisphere making it difficult to judge at what angle of declination one would locate the desired celestial object. Further, the sky contains many more celestial objects than the pictorial representation can possibly contain, making it difficult to determine which pattern of stars on the pictorial representation corresponds to a particular region of the sky. 
     U.S. Pat. No. 5,704,653 to Lee discloses a pictorial representation of the celestial hemisphere in which is incorporated an electronic compass. The electronic compass identifies which region of the sky the operator of the Lee device is facing. The compass assists in pointing to the approximate azimuth of the celestial object. However, the task of determining the proper declination, and performing a mental translation from a set of maps, to the particular region of the sky one is observing, is still handled unaided by the operator. This leaves most of the work in locating a celestial object to the operator. 
     U.S. Pat. No. 4,938,697 to Mayer contains a somewhat clumsy and complicated mechanical method of directly observing a region of the sky without a map. It requires a good deal of understanding of the devices workings to obtain any success, in addition it can only locate a star-group or constellation. 
     U.S. Pat. No. 4,970,793 to Atamian contains a method for location of stars and constellations, yet it requires manual alignment of a sphere oriented with the sky to work properly. It also has the same scale difference problem mentioned above that U.S. Pat. No. 3,863,365 that leaves much ambiguity in observing heavenly bodies. 
     Thus, there is a need for a more user friendly device to locate celestial objects. 
     SUMMARY OF THE INVENTION 
     An improved celestial object locating device has been discovered. In an aspect of the invention, a device allows a user to point the device at a celestial object and the device announces to the user of the celestial object&#39;s identity. In another aspect of the invention, the user directs the device to find a desired celestial object. This is done through a view port and the instrument detects the geographical location of the user, the time, and the azimuth and nadir of the direction of the view port automatically, resulting in a simple to use celestial object location device. Other embodiments of the invention comprise combinations of the above aspects. These aspects of the invention eliminate the disadvantages of the prior art concerning scale and translation from a celestial map. Further, in an aspect of the invention, the device is hand-held or attached to a computational device such that the device is portable. 
     In an aspect of the invention, a celestial object location (COL) device for viewing from a location at a time and a date comprises a viewing means, a processor, a 3-axis magnetic sensor, a 3-axis gravitational sensor, a location means, a time means, and a database. The viewing means assists a user of the COL device in observing along a viewing axis defined by an azimuth angle and a nadir angle. The 3-axis magnetic sensor is adapted to provide the processor with azimuth data representing the azimuth angle. The 3-axis gravitational sensor is adapted to provide the processor with nadir data representing the nadir angle. The locations means provides location data representing the location to the processor. The time means provides time and date data representing the time and date to the processor. The database is adapted to be accessed by the processor and provide data such that the processor determines celestial coordinates of right ascension and declination corresponding to the viewing axis based on the azimuth data, the nadir data, the location data, and the time and date data. 
     In a further aspect of the invention, the viewing means comprises a viewing channel adapted to enable a user to observe through the device along the viewing axis. 
     In a further aspect of the invention, there is a direction indicator adapted to announce directions to change the angular orientation viewing axis, wherein the direction indicator is further adapted to be controlled by the processor and comprises a visual indicator, an auditory indicator, or a tactile indicator. 
     In a still further aspect of the invention, the direction indicator is adapted to be controlled by the processor, comprises an illuminate-able visual display that is viewable by the user when the user is observing through the viewing channel, and is adapted to illuminate at least a portion of the visual display such that a user changes the viewing axis based on the illuminated visual display. The visual display may be a circularly arranged series of illuminate-able arrows, wherein the processor and the arrows are adapted such that the processor directs a least a portion of the arrows to be illuminated. 
     In an aspect of the invention, a reticule is present and adapted to be viewable by the user when the user is observing through the viewing channel. 
     In an aspect of the invention, the viewing means comprises a display screen adapted to display an image observed along the viewing axis. Further, there may be a direction indicator adapted to announce directions to change the angular orientation viewing axis, wherein the direction indicator is further adapted to be controlled by the processor and comprises a visual indicator, an auditory indicator, or a tactile indicator. 
     In an aspect of the invention, the device comprises a housing and wherein the viewing means comprises a viewing channel extending through the housing and adapted to permit a user to observe through the viewing channel along the viewing axis. In a further aspect of the invention, the processor is spaced apart from the housing. In an additional aspect of the invention, the housing is adapted to be held by the user while the user is observing through the viewing channel. 
     In a further aspect of the invention, the COL device comprises a direction indicator adapted to announce directions to change the angular orientation of the viewing axis, wherein the direction indication is further adapted to be controlled by the processor and comprises a visual indicator, an auditory indicator, or a tactile indicator. This COL device may further comprise a user interface adapted for the user to input an identification of a celestial object or celestial coordinates to the processor. Additionally, the processor and the database is adapted such that the processor directs the user via the direction indicator to change the angular orientation of the viewing axis such that the viewing axis is aligned with the celestial object or the celestial coordinates, wherein the database comprises data associating the identification of the celestial object with the celestial object&#39;s celestial coordinates. 
     In still further aspects of the invention, the processor is adapted to announce to the user via the direction indicator that the viewing axis is aligned with the celestial object or the celestial coordinates. Additionally, the user interface may be adapted for the user to input an identification of a celestial object comprising multiple celestial coordinates. In this case, the processor and the database is adapted such that the processor directs the user via the direction indicator to change the angular orientation of the viewing axis such that the viewing axis is serially aligned with the multiple celestial coordinates of the celestial object, thereby the user is provided with a tour of the celestial object. In a still further aspect of the invention, the user interface is adapted for the user to input a signal to the processor to direct the user via the direction indicator to change the angular orientation of the viewing axis from a current celestial coordinate to a next multiple celestial coordinate. 
     In a further aspect of the invention, there is a user interface adapted for the user to signal to the processor to identify a celestial object or celestial coordinates aligned with the viewing axis, wherein the database is adapted for the processor to access the database for data related to the celestial object or the celestial coordinates. The user interface is further adapted to announce to the user the celestial object or the celestial coordinates. In a still further aspect of the invention, the user interface is adapted for the user to signal to the processor through activating a manual switch or through an auditory command, and for the processor to announce to the user through a visual display or a speaker. 
     In a further aspect of the invention, the database is adapted to be changed by the user editing the database through a user interface of the device in functional communication with the processor, a plug-in module adapted to be in functional communication with the processor, or an information transfer system adapted to be in functional communication with the processor. 
     In an aspect of the invention, the location means comprises a user interface adapted for the user to input location information to the processor, wherein the database is adapted to provide the processor with the location data based on the inputted location information. 
     In an aspect of the invention, the time means comprises a time keeping device adapted to provide the time and date data to the processor. 
     In an aspect of the invention, the location means and the time means comprises a global positioning device adapted to provide the location data and the time and date data to the processor. 
     In an aspect of the invention, there is an output device for announcing the elevation angle of the viewing axis, wherein the elevation angle is nadir angle minus 90 degrees. 
     In an aspect of the invention, there is an output device for announcing a compass heading as a function of the azimuth angle and the nadir angle. 
     In an aspect of the invention, there are compensation instructions readable by the processor and/or compensation data in the data base such that the processor compensates for procession, earth elongation, magnetic variation, parallax, nutation, or a combination thereof. 
     In an aspect of the invention, there is a temperature sensor adapted to interface with and enable the processor to make thermal error compensations of the magnetic and gravitational sensors. 
     In an aspect of the invention, the database contains additional data representing when a celestial object is visible to a naked eye at the location, the device further comprises an announcement device functionally connected to the processor, and the processor is adapted to announce through the announcement device the additional data representing when the celestial object is visible to a user at the location. 
     In an aspect of the invention, there is a celestial object location device for use from a location at a time and a date comprising: 
     a. a housing comprising a viewing channel adapted for a user to observe through the viewing channel and along a viewing axis to a position in the sky aligned with the viewing axis, wherein the housing is adapted to be held by the user while the user is observing through the viewing channel; 
     b. a processor; 
     c. a 3-axis magnetic sensor adapted to provide the processor with azimuth data representing an azimuth angle of the viewing axis; 
     d. a 3-axis gravitational sensor adapted to provide the processor with nadir data representing a nadir angle of the viewing axis; 
     e. a location data input device adapted to provide the processor with location data representing the location of the celestial object location device; 
     f. a time data input device adapted to provide the processor with time and date data representing the time and date of a use of the device; 
     g. a user interface for inputting user data to the processor and announcing information to the user; 
     h. a direction indicator adapted for the processor to announce through the direction indicator to the user directions for changing the angular orientation of the viewing axis; and 
     i. a database adapted to be accessed by the processor such that the processor, based on the azimuth data, the nadir angle, the location data, the time and date data, the user data, and the database, announces to the user: 
     i) through the user interface an identification of a celestial object aligned with the viewing axis; 
     ii) through the user interface celestial coordinates aligned with the viewing axis; or 
     iii) through the direction indicator directions for the user to change the viewing axis based on user data comprising identification of a celestial object or a celestial coordinate. 
     In an further aspect of the invention, the processor is spaced apart from the housing. 
     In a further aspect of the invention, the direction indicator comprises a circularly arranged series of illuminate-able arrows that are in functional communication with the processor, the arrows being adapted such that illuminated arrows are visible by the user observing through the viewing channel, and the direction indicator and the processor are adapted to illuminate at least a portion of the arrows such that a user changes the angular orientation of the viewing axis based on the illuminated portion of the arrows. 
     In a further aspect of the invention, the database is adapted to be changed by the user editing the database through the user interface, a plug-in module adapted to be in functional communication with the processor, or an information transfer system adapted to be in functional communication with the processor. 
     In an aspect of the invention, there is a process for observing celestial objects comprising the steps of 
     a. providing a user with a device for observing the celestial objects along a viewing axis; 
     b. identifying an azimuth angle of the viewing axis via a 3-axis magnetic sensor adapted to determine the azimuth angle; 
     c. identifying a nadir angle of the viewing axis via a 3-axis gravitational sensor adapted to determine the nadir angle; and 
     d. determining celestial coordinates of right ascension and declination based on the azimuth angle, the nadir angle, a location of the device, and a current time and date. 
     In a further aspect of the invention, the providing step further comprises a step of holding the device, the 3-axis magnetic sensor, and the 3-axis gravitational sensor in a hand of the user. In a still further aspect of the invention, the 3-axis magnetic sensor and the 3-axis gravitational sensor are integral to the device. 
     In a further aspect of the invention, there is a step of directing a processor to receive data representing the azimuth angle, the nadir angle, the device location, and the current time and date, consult a database, and announce the celestial coordinates via an announcement device. 
     In a further aspect of the invention, there is the step of inputting to a processor an identification of a desired celestial object wherein the processor is also directed to perform the determining the celestial coordinates step. Further, there is a step of directing the processor to announce, via a direction indicator, instructions understandable to the user concerning how to change the angular orientation of the viewing axis until the desired celestial object is aligned with the viewing axis. In a still further aspect of the invention, there is the step of repeating the directing the processor to announce step such that the user is instructed to tour through portions of the desired celestial object. 
     In a further aspect of the invention, there is the step of inputting to a processor a desired celestial coordinate wherein the processor is also directed to perform the determining the celestial coordinates step. There is also the step of directing the processor to announce via a direction indicator instructions concerning how to change the angular orientation of the viewing axis until the desired celestial coordinate is aligned with the viewing axis. 
     In an aspect of the invention, a process of observing a celestial object comprises the step of providing an embodiment of the invention described in this disclosure and the step of updating the database with additional data concerning the celestial object such that a user of the device directs the processor to announce the directions to change the angular orientation of the viewing axis such that the viewing axis is aligned with the celestial object via the direction indicator. In a further aspect of the invention, the updating step comprises the step of functionally connecting a plug-in module comprising the additional data to the device or the step of downloading the additional data to the database via an information transfer system. The downloading step may comprise the step of accessing the Internet to retrieve the additional data. Further, accessing step comprises the step of purchasing the additional data. 
     Further objects and advantages will become apparent from a consideration of the drawings and ensuing description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic perspective view of a user identifying a celestial object with a device according to an embodiment of the invention. 
     FIG. 2 is a detail perspective view of the device shown in FIG.  1 . 
     FIG. 3 is a view through the device shown in FIG. 1 while observing a celestial object. 
     FIG. 4 is a schematic representation of the components of the device shown in FIG.  1 . 
     FIG. 5 is a schematic view of an embodiment of the invention incorporating a digital personal assistant. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the figures, wherein like reference numerals refer to like elements throughout the figures, and specifically to FIG. 1, a celestial object location device (COL device)  10  is being used by a user  12  to locate a celestial object  14 . The COL device  10  according to the shown and a preferred embodiment of the invention, has a generally cylindrical housing  16  adapted to be hand-held. Other embodiments of the invention may have housings of other shapes and may or may not be hand-held. 
     The housing  16  of the COL device  10  has a first view port  18  that is held proximate to the user  12  and a second view port  20  proximate to the celestial object  14 . During use, the view ports  18  and  20  are aligned between the user  12  and the celestial object  14  and the COL device  10  is adapted such that the user views the celestial object through the COL device along a viewing axis  34 . 
     Other embodiments of the invention may have an optical sensor that is positioned to view the celestial object  14  and transmit an image from the optical sensor to a view screen such that the user observes the image on the screen (not shown). In further embodiments of the invention, the COL device  10  is mounted to a support or a frame and is adapted to be positioned mechanically, electronically, pneumatically, or by some other suitable means other than by direct manual manipulation (not shown). The positioning of the mounted COL device  10  may be directed by the user through switches, by a functionally integrated computational device, or a combination of both. Still further embodiments of the invention may have the COL device  10  mounted to a support or a frame and may be positioned through direct manual manipulation, thereby providing stability to the device (not shown). 
     Referring now to FIG. 2 as well, the COL device  10  comprises the housing  16 , the view ports  18  and  20 , and a data input/output interface (IOI)  30 , and a viewing button or switch  32 . A viewing axis  34  is shown extending axially through the cylindrical housing  16 . The IOI  30  is comprised of a display screen  36  for displaying data, such as in the form of menus and results, as explained further below. The  101   30  also comprises a plurality of buttons or switches  38  for inputting data and commands, such as moving through menus on the display screen  36  and inputting queries. The viewing switch  32  is positioned and adapted to be easily activated by the user&#39;s thumb or finger when the user is observing through the COL device  10 . 
     Referring now to FIG. 3, the COL device  10  is shown displaying the view the user has when the celestial object  14  is aligned with the viewing axis  34  of the device  10 . The user  12  is observing the object  14  through a viewing channel  46  that extends through the COL device  10 . The viewing channel  46  is defined by an interior surface  48  of the housing  16  in the shown embodiment. Further, the viewing channel  46  is bounded by the view ports  18  and  20 . 
     Shown extending from the left side of the housing  16  is the  101   30  and shown extending from the bottom of the housing is switch  32 . Other embodiments of the invention may have other configurations of the IOI  30  and the switch  32 . 
     Referring now to a viewing portion  40  of the COL device  10 , a circularly arranged series of illuminating directional arrows  42  are positioned adjacent to the interior surface  48  of the housing  16 . The arrows  42  are illuminated as required to direct the positioning of the COL device  10  during use. Eight arrows  42  are shown but other embodiments of the invention may have more or less arrows. The size, shape, and number of the illuminating arrows  42  is not paramount to the function performed. What is paramount is that there is a way for the COL device  10  to inform the user  12  of a required change in viewing axis to align the device with a particular location in the sky and, therefore, the arrows  42  are direction indicators. There are many variations on color and shape of the direction indicators as well. Other embodiments of the invention may have other suitable ways for visually informing the user how to direct the COL device  10 , such as illuminating dots or borders. The illumination of the arrows  42  may be accomplished by any suitable means, such as LED or fiber optics. In a preferred embodiment of the invention, the arrows are not an overlayed image. 
     Embodiments of the invention have many variations on the operation of the arrows  42  or other suitable direction indicators. In embodiments of the invention, the arrows  42  blink at different rates, change color, or intensity depending on how far the user  12  has to angularly change the viewing axis  34 . For example, if the user  12  is very close to the desired viewing axis position, the arrow or arrows  42  blink quickly and if the user were further away the arrow or arrows  42  may blink slowly. Other embodiments of the invention may use tactile, such as vibrational, or auditory means for announcing direction. 
     In another embodiment of the invention, once the viewing axis  34  is aligned with the desired celestial object  14 , the arrows  42  may all light up or blink. Still other embodiments of the invention may have devices that announce visually, tactilely, or auditorily when the desired angular position of the COL device  10  is achieved, such as sounding a beep or synthesized voice. 
     A reticule  44  is centrally positioned in the viewing portion  40 . The reticule  44  is helpful in centering the COL device  10  on the celestial object  14 . Other embodiments of the invention may have other reticule or cross-hair designs or not have any means for centering the celestial object  14 . In still other embodiments of the invention, the reticule  44  may be used to announce achievement of a desired angular position either by illuminating with more intensity, ceasing illumination, or flashing. 
     Referring now to FIG. 4, incorporated into the COL device  10  are a number of other components to operate the device as shown in schematic representation  50 . In the shown embodiment, a processor  52  integrates the components which comprise a 3-axis magnetic field sensor  54 , a 3-axis gravitational field sensor  56 , a time keeping device  58 , input devices  60 , a celestial object database  62 , illuminating arrows  64 , and a display  66 , which are arranged in a counterclockwise fashion starting at the top left corner of FIG.  4 . In a preferred embodiment of the invention, the components are incorporated into the housing  16  of the COL device  10 . 
     Referring now to FIG. 5 as well, in other embodiments of the invention, a COL device  110  may comprise a portion external to the housing  116  comprising one or more of the components, such as the processor  52  and/or the database  62  residing in an auxiliary device  180  that is in functional communication with the remainder of the components. Examples of suitable auxiliary devices include a personal digital assistant, a desk top computer, or a lap top computer, however, embodiments of the invention are not limited to these examples. Therefore, in embodiments of the invention, the processor is spaced apart from the housing. Other embodiments of the invention incorporate the time keeping device  58 , the input devices  60 , and/or the display  66  into the auxiliary device  180 . Still other embodiments of the invention have multiple auxiliary devices. It is understood that the term “auxiliary device” in the below claims is to be interpreted as encompassing one or more auxiliary devices. 
     In another embodiment of the invention, the configuration of the COL device  10  may not require the IOI  130  or the switch  132  and the input and output of data may be accomplished by the auxiliary device  180 . In another embodiment of the invention, the database  62  may be communicated to through an information transfer system, such as a network system, connection to another database, or via the Internet  182 . The components in the housing  16  and the auxiliary device  180  may be in functional communication through a physical conduit  184  capable of data transfer, such as electrical or optical signal transfer media, or via a process not requiring a physical conduit, such as processes utilizing infrared or RF technology, for example. 
     Referring back to FIG. 4, input devices  60  enable the user to input data into the processor  52 . In the embodiment of the invention shown in FIG. 1, the input devices  60  correspond to the  101  switches  38  and the switch  32 . Other embodiments of the invention may have data input devices of any suitable type, such as auditory for example, or the data input devices may be incorporated into the auxiliary device  180 . 
     The processor  52  is in communication with the celestial object database  62  in order to retrieve information about celestial objects therefrom. The information in the databases of the embodiments of the invention may differ, but those skilled in the art understand the variety of information that may be in the database. The database  62  may also contain retrievable data for any other suitable purpose, such as linking a geographical location with a latitude and a longitude coordinate. 
     The processor  52  analyzes the input from the sensors  54  and  56 , the timekeeping device  58 , the input device  60 , communicates with the database  62  as required, and outputs information through the arrows  64  and the display  66 , which corresponds to the IOI display  36  of the embodiment shown in FIG.  1 . 
     The processor  52  receives information from the magnetic field sensor  54  and the gravitational field sensor  56  in order to calculate the direction or vector that the COL device  10  is pointing. The vector is a three dimensional vector relative to the azimuth angle and the nadir angle of the COL device  10 . The azimuth angle is the angle between magnetic north and the device pointing direction. The nadir angle is the angle between straight down into the earth and the device pointing direction. The azimuth vector is determined using the magnetic field sensor  54  and the nadir angle is determined using the gravitational field sensor  56 . The information from the sensors is processed by the processor  52  using means commonly known by those skilled in the art. 
     The use of a 3-axis gravitational sensor  56  is required to determine the position of the nadir angle. The nadir angle is the three dimensional angle between two particular vectors. The first vector is in the direction which the viewing axis  34  is pointed. The second vector is pointing straight into the ground, towards the center of mass of the earth. In a preferred embodiment of the invention, the 3-axis gravitational sensor will employ a minimum of three individual accelerometers to determine the 3-axis gravitational field vector, although other embodiments of the invention may use devices other accelerometers. The accelerometers used must be capable of sensing a static force, in this case the earth&#39;s gravitational force of 1 g. These types of accelerometers are readily available devices offering ample precision to perform this function. In an embodiment of the invention, the three individual accelerometers are oriented orthogonally 90 degrees from each other in the X Y, and Z planes. Through common geometric calculations the individual readings from the three accelerometers can be combined to yield the nadir angle. 
     Without at least three accelerometers in the 3-axis gravitational sensor  56 , in contradistinction to Norton which discloses the use of one or two accelerometers, there can be large errors in the accuracy of the COL device  10 . These errors would be dependant on what angle the user  12  held the COL device  10  and how they oriented the ‘roll’ axis of the device. In a device which only uses the earth&#39;s magnetic field, and the earth&#39;s gravitational field is used to sense orientation, the only way to avoid these errors is by using 3-axis sensors for measuring the magnetic field and the gravitational field. These errors cannot be ignored as they may easily be larger than one field of view which would render the COL device  10  useless. 
     Once the direction vector of the COL device  10  is determined, the processor  52  uses longitude, latitude, local time and date data of the COL device  10  to perform a translation of the device direction vector into celestial coordinates. In an embodiment of the invention, the longitude and latitude data is manually input by the user via the input devices  60 . The longitude and latitude may be in the form of coordinates, but may also may be indirectly input by the user  12  entering another geographical indicator into the COL device  10 , such as a town, county, zip code, portion of a state, state, or region of the county, in which case the database  62  or another database contains the information to assist in determining the longitude and latitude of the device  10 . The local time and date may be inputted manually as well, but in a preferred embodiment of the invention, the time keeping device  58  inputs this information to the processor  52 . 
     In another embodiment of the invention, the COL device  10  includes a global positioning system receiver (not shown) or any other suitable device for automatically inputting the longitude, latitude, time and date information, or portions thereof, to the processor  52 . 
     The processor takes the direction vector information received from the sensors  54  and  56 , the time and date information from the time keeping device  58 , and the information from the user via the input devices  60 . This information is used by the processor  52  to perform a search against the database to determine the celestial coordinates of right ascension and declination to which the viewing axis  34  is pointing. Embodiments of the invention have one or numerous functions to perform at this point, as discussed below. 
     Identification of a Celestial Object. 
     Referring now to all the figures, the user  12  points the COL device  10  to a celestial object  14  whose identification is desired. More specifically, the user aligns the center of the viewing portion  40  with the celestial object  14 , such that the viewing axis  34  is aligned with the object  14 . The user activates the switch  32  to input to the processor  52  that the object  14  has been located. The processor  52  then receives the data from the sensors  54  and  56 , the time and location data, consults the database  62 , and displays on the screen  36  the information about the celestial object  14 . 
     Location of a Celestial Object 
     Another common mode of operation that the COL device  10  supports is to help the user  12  locate the celestial object  14  in the sky. For example, if the user  12  wants to know where Saturn is currently located they would use the “locate” mode. To locate the desired celestial object, the operator selects Saturn from a list of available objects via the  101   30 . Then, the user  12  views through the COL device  10 . The processor  52  directs the user to change the orientation of the COL device via the illumination of the arrows  42 . For example, if the viewing axis  34  needs to be oriented more vertically and to the left, the arrows  42  in the upper left quadrant of the view portion  40  will light up. Once the desired celestial object, Saturn, is aligned with the viewing axis  34 , all of the arrows  42  will not be illuminated, may blink, or the device may utilize another suitable device for announcing to the user  12  that alignment has occurred. 
     In an embodiment of the invention, the COL device  10  may track the ecliptic for the user. An example of an ecliptic is the plane of the earth&#39;s orbit as it forms an imaginary arc across the sky during rotation about the sun. This arc can be traced using the illuminated arrows  42  as a guide. Further embodiments of the invention may track paths of other celestial objects, such as comets and satellites. 
     Tours of Constellations and Sky Tours 
     Since many constellations cover large areas of the sky and include multiple stars, an embodiment of the COL device  10  gives a tour of the constellation. In an embodiment of the invention, the constellation is chosen and input through the IOI  30 . The COL device  10 , through the arrows  42  directs the user  12  to align the viewing axis  34  with the brightest star in the constellation. Once the alignment is achieved and the COL device  10  indicates it, the user activates the switch  32 , and COL device directs the user to the next brightest star in the constellation. This process continues until the stars of the constellation have all been aligned with the viewing axis  34  in a serial fashion, from a current celestial coordinate associated with a current celestial object to a next celestial coordinate associated with a next celestial object. Similarly, sky tours of celestial objects may also be included in an embodiment of the invention, such as a sky tour of the Zodiac constellations. 
     Other Modes of Operation 
     Embodiments of the invention may have several other modes of operation which are possible based on the instrumentation in the COL device  10 . The COL device  10  may function as a digital compass and display the compass heading. In an embodiment of the invention, the COL device  10  uses both the azimuth and nadir data to compensate for when the COL device is not held parallel to the ground. 
     The COL device  10  may function as an elevation angle instrument, and display the elevation angle. The COL device  10  may display the celestial coordinates to which it is pointed. This last mode of operation is useful for an astronomer who has the celestial coordinates of an object (from a table or chart) which is not already in the device&#39;s database. The COL device  10  may display the date and time in various time standards including local, UT or GMT times. 
     In other embodiments of the invention, the COL device  10  may perform a series of compensations to improve the accuracy of the instrument. These include but are not limited to: procession (earth axis wobble), earth elongation (earth not completely circular), magnetic variation (difference between true north pole and magnetic north pole), parallax (error in celestial coordinates due to earth orbit), and nutation (earth axis “nodding” on processional circle). Embodiments of the invention may include a temperature sensor for thermal error compensation of the magnetic and gravitational sensor arrays. The processor may compensate for unstable shaky hands of the operator in some embodiments of the invention. 
     An embodiment of the device may enable the database  62  to be updated with new information concerning celestial objects and the current magnetic pole location. This would be particularly useful for tracking artificial satellites where orbital elements can change based on mission requirements, for example, the Mir space station, the International Space Station, and the Hubble Space Telescope. This would also be useful for newly launched artificial satellites placed in orbit after the unit is in the field. For example, the Space Shuttle. This would also be useful for newly discovered celestial objects like comets and asteroids. Adding information about these celestial objects to the database may be accomplished by user entry, through an expansion chip or another type of plug-in module, or electronically, for example downloading from another computer through direct connection, over a telephone line, or via another type of information transfer system, such as a network or the Internet. For example, a modem port would allow the device to plug into the phone system, call a number, and update the database and magnetic north pole position online after the device was fielded. 
     Other embodiments of the invention, the COL device  10  would either come with astronomy tutorials in the database  62 , in another database (not shown), in a plug-in module, downloadable from another computer either directly, over the telephone lines, or via another type of information transfer system, such as a network or the Internet. In a similar fashion, downloadable constellation tours and sky tours may also be available in some embodiments of the invention. 
     In another embodiment of the invention, the COL device  10  could include calculations well known to those skilled in the art for notifying the operator of the next naked eye viewing opportunity for artificial satellites. For example the user could choose the International Space Station, then the COL device  10  could inform them of the next time the International Space Station would be visible with the naked eye. 
     In another embodiment of the invention, the COL device  10  may include a reflex viewer which would superimpose an illuminated reticule and direction indicators in the viewing area, allowing for the user  12  to hold the device further out from the eye. This would also prevent the user from observing through the viewing channel  46  too far off parallel to the viewing axis  34 . 
     The COL device  10  is not limited to being of a hand-held size and there are many possible interpretations of hand-held size. In addition the COL device  10  may function on a much larger or smaller scale so the scope of the embodiments of the invention should not be limited to that of a hand-held size. 
     In alternative embodiments of the invention, the COL device  10  may have other input/output devices, other switches, other locations thereof, and many variations thereof, for example in number, arrangement, size, and type, including options wherein there are no input/output devices or switches on the housing  16 . 
     In another embodiment of the invention, a viewer or reflex viewer could be located outside the housing  16  in such a manner so as the user  12  may still sight parallel to the viewing axis. 
     While the above description contains many specifics, these should not be construed as limitations on the scope of the device, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible.