Abstract: A system to help a viewer find stars, planets, deep sky objects and constellations is disclosed. The system has a series of sky maps showing different views of the sky. One or more tables is provided for each map. The tables assist in corresponding the sky map to the sky. The tables have coordinates corresponding to times and dates and inform the viewer as to the direction in which he should look, the way in which the sky map should be oriented and whether the viewer should look high in the sky, low in the sky or in-between.

Abstract: A space-time tracker for announcing the time and tracking the celestrial bodies on the spot of observation comprises a clock mechanism with clock hands on a dial of 24 hours and a synchronic motor for driving a star atlas and a plurality of planet driving devices which actuate a plurality of annular displays moving around a moon/star ring to periodically show an on spot planet thereon. The space-time tracker also indicates the variations or deviations of the solar calendar and the lunar calendar and the times of different time zones around the world. This disclosure is characterized in automatically and perfectly demonstrating the relationship between the time and space.

Abstract: A multipotent astrolabe is used to determine the positions of various celestial bodies by applying the circular star atlas and taking into account ephemeral time and the porjections of the relative positions of the moon, the sun and the stars as viewed from the earth. In addition, the positions of the planets of the solar system are included in the multipotent astrolabe to increase the utility of this instrument in the domain of skywatching.

Abstract: An accurate, easy to use solar compass which permits a user to locate true north or to locate azimuth lines. The user calculates the solar time and determines the declination of the sun from the emphrimis. The user adjusts the compass to compensate for the declination of the sun and the physical location of the user. The user thus determines true north accurately using a shadow cast by a stylet. An important aspect of this invention is that it is an accurate solar compass.

Abstract: An apparatus and method for compensating for the measured variation in bearing between magnetic north as read on a compass and true north as may be determined by juxtaposition with the sun at a given time. Such apparatus and method is particularly useful in vessels or other environments in which there are either or both disturbances in the natural magnetic flux pattern of the earth and natural variations between natural magnetic and true north.

Abstract: An apparatus which can be carried to a field sight to locate current and future positions of geosynchronous satellites orbiting the equator in the Clark Belt Altitude. The apparatus corrects the error in viewing angle by providing corrections in longitude and latitude deviations caused by the location of the antenna. The apparatus will provide the user a means of accurately locating a satellite with regard to existing terrain and the obstacles which would interfere with signals between the ground position and the satellite.

Abstract: The instrument comprises a sphere mounted in a holder between two rings, so that the sphere is held in specific spatial relationship to holes in the holder which define a line of sight of the instrument. A flat cylindrical assembly comprising a bubble level and a compass is mounted on the sphere with the center of the assembly at a point which represents the point on the earth's surface intersected by a line from the earth's center to the geostationary satellite served by the instrument. The assembly touches and moves between the rings. A mark on this assembly points in the direction of a point on the sphere which represents true North relative to the center of the assembly. A map of the area served by the satellite is marked on the sphere. A scale marked in degrees and having a base point is mounted between the rings with its centerline parallel to the rings. The map is marked with points representing major locations at which antennas may be located.

Abstract: A sundial including a strip-shaped body with surfaces substantially in the form of helicoids. The body is made of a rather thin material. At least one of the helicoids is provided with time markings. As a result, the sundial is very simple to manufacture, and it is very easy to set up. Moreover, it is very easy to read the time, even at a relatively long distance.

Abstract: The automated repeating sextant (ARS) is a navigational instrument suitable for air, sea and land use. The ARS uses an electronic artificial horizon, an A/D conversion board and either microchips or a computer, with software, to read a celestial body's altitude above the horizon repeatedly in a brief period of time, and then compute a line of position from a statistically enhanced mean altitude; after a second or any successive line of position has been obtained the instrument either provides the latitude and longitude of the navigator, or combines the latitude and longitude with a graphic portrayal of the position on a simplified grid map. The instrument averages numerous individual observations and is relatively small, light and fast. The ARS may be embodied in a fully automated, continually-operating mode with a micro-computer, or may be embodied in a handheld version that is switched on and off.

Abstract: An apparatus for viewing a representation of the celestial vault including a tube bearing a ring of graduations that indicate the dates of the days of a year, and a tube bearing a ring of graduations that indicate the hours of a day. The tubes are axially aligned and rotatable with respect to each other about the axis. One tube contains a representation of the night sky, and the other contains an element, such as a lens, for viewing the representation. The tubes are separably joined so that they can be disassembled, each tube rotated end-over-end through 180.degree., and the tubes reassembled. In one condition of assembly, a sky representation of the northern hemisphere is used, and in the other condition of assembly, a sky representation of the southern hemisphere is used.

Abstract: An astronomical correlator for determining the position of the stars and method of using the same includes a transparent hollow globe having phosphorescent indicia. A horizon ring member and a latitude scale member can be utilized for defining the field of view of the night sky in correlation with the date and time. A flash light assembly can activate phosphorescent material, both on the transparent globe and on an alignment assembly, that permits a sighting by the observer of the night sky through the globe for determining the identification of stars.

Abstract: There is proposed an instrument for determining true bearing during daytime using the sun as a reference preferably for use together and as an attachment to known angular measuring instruments, such as geniometers, the instrument consisting of a shadow producing member to produce a shadow on a reference member. The shadow is to be cast at a predetermined location on the reference member when the shadow producing member is exactly aligned with the sun.

Abstract: A typical plate and gnomon sundial with an enlarged dial plate and an extended gnomon is provided with latitude and longitude displacement indicia lines on the dial plate, beneath the gnomon and beyond the time indicia. A point is established on the gnomon from which a plumb line to the latitude and longitude displacement indicia lines can be determined. The latitude and longitude displacement indicia lines are placed so that when a plumb line from the point on the gnomon intersects the point of intersection of the site latitude indicium line with the site longitude displacement indicium line, the gnomon will be inclined to the horizontal at an angle equal to the latitude of the site and the plane(s) containing the gnomon and the 12 o'clock noon indicium line(s) will be inclined to a vertical plane containing the gnomon at an angle equal to the difference between the longitude of the site and the longitude of the time zone meridian.

Abstract: A reticle plate provided with a reticle and three concentric circles of ving diameter and methods of use thereof, the invention allows a user to establish a north-oriented or south-oriented line by alignment of selected circumpolar stars with the circles. The circles are located on the reticle plate in positions determined by angles which exist between the celestial north (or south) pole and the particular low-magnitude circumpolar stars chosen as sighting points, the radii of the circles being directly proportional to the objective lens focal length of the theodolite or optical instrument within which the plate is used. A first method of the invention allows unambiguous location of the north or south pole by alignment of each of three selected stars with one each of the three circles. A second method provides data to a user sufficient to locate the pole by alignment of innermost and outermost circles respectively with one each of two of the selected stars.

Abstract: A longitude finder for locating the longitude on the earth of a defined location at which the user of the device is positioned. The device includes a reflective surface for viewing an image of one body in the solar system, such as the moon or a planet, while directly observing another body such as the north star. One specific form of the device is a mirror having side panels secured perpendicular to the mirror in parallel spaced relation to permit the user to directly view the north star above an image in the mirror of the moon or a defined planet. The other form of the device includes a sphere such as made of glass with side panels and handles for supporting this sphere whereby the first body in the solar system such as the north star is observed directly and a first reflection of the moon or a planet is seen in the outer surface of the sphere and a second reflection from the inner surface of the sphere while directly observing the north star in vertical alignment with the reflections.

Abstract: A telescope (10) is precisely pointed by a detent mechanism (32) in a sighting direction (18) after a motor (22) generally positions the telescope. The detent mechanism includes a roller assembly (60) precisely journalled at one end of an arm (38) which is biased into contact with a precisely formed V-groove (36) on the telescope by a spring 72.

Abstract: A sextant for indicating the angular separation between two objects, including two members interconnected at a pivot point, means for adjusting the angle between the members to be indicative of the angular separation between the objects, the means for adjusting including coarse and fine adjustment means, and a pair of encoders for converting the respective positions of the coarse and fine adjustment means to signals which are together indicative of the angular separation. In other aspects, there is a single encoder having a track on the sextant arc and a sensor on the tangent arm; and an indicator tells the user when the sextant has been set to the prestored altitudes of reference celestial bodies.

Abstract: A sextant having a telescope, a fixed split horizon mirror, a pivotal index arm supporting an index mirror and a stepping motor coupled to the index arm to cause rotation thereof on receipt of control pulses, the number of pulses applied to the stepping motor being proportional to the angle of the resultant pivotal movement of the index arm and thus the altitude angle of a heavenly body being observed through the sextant telescope. A microprocessor is programmed with information relating to the position data of heavenly bodies and monitors the pulses applied to the stepping motor and is arranged to calculate in accordance with known navigational equations, lattitude and longitude from time data and pulses applied to the stepping motor indicative of the altitude angle of the heavenly body being observed.

Abstract: A device for determining the annual exposure of a site which comprises a viewer having a lens with markings provided thereon for determining the line of travel of the sun at a given latitude for selected dates of the year and indicating the position of the sun at selected times of the day. Interchangeable lenses are provided for different latitudes and are changed by removing a bezel which attaches the lens to the hollow cylindrical body of the device.

Abstract: A polar mount for a parabolic satellite tracking antenna insures close tracking of the antenna to a synchronous satellite track sector bearing multiple satellites within the earth's equatorial plane. The apparatus tilts the polar pivot axis of the antenna and the dip of the antenna boresight to cause an elliptical antenna track which better approximates the track of the synchronous satellite. The antenna is provided with a removable Polaris telescope alignment fixture to permit selective adjustment of the tilt angle at a sine setting derived from specific formula prior to aligning the antenna mount for true north and with further ajustment for dip angle or declination to achieve alignment accuracy within thirty arc-seconds of the antenna boresight to the satellite track sector bearing the satellites whose signals are to be received. A zero backlash linear actuator selectively drives the antenna about the polar axis to sweep the satellite track sector, with exacting alignment, from satellite to satellite.

Abstract: A device to locate the position of a communication satellite with respect to a specific site on the earth's surface including a transparent screen having markings to indicate the positions of one or more satellites for that site with respect to a horizontal platform and a north orientation, a table including an arcuate means to mount the screen, a wide-angle viewer fixed to the table with its axis perpendicular to the tangent of the arcuate means at its south position, a compass fixed to the table oriented with north-south parallel to the axis of the wide-angle viewer and a level to indicate when the tabletop is horizontal.

Abstract: Celestial navigational instrument and method of determination of local latitude and local hour angle of Aries by a single sighting on the night sky. Greenwich hour angle of Aries and latitude are obtained by simple reference to the instrument's scales and to a watch and Nautical Almanac; sight reduction tables, plotting boards and charts are not required. The instrument comprises a sky assembly and a horizon assembly. The sky assembly includes a closed central axial tube on which are rotatably mounted a combined periscope/telescope tube for sighting a first star and a periscope tube for sighting a second star, the siderial hour angular positions of both of which are set with respect to a single sky wheel and the polar distances of each periscope turret with respect to protractor scales. The horizon assembly comprises a periscope/telescope assemby mounted on the central axial tube and indexed to a horizon wheel and protractor scale to read the local hour angle of Aries and local latitude.

Abstract: A polar axis finder for an equatorial mounting telescope has an objective lens and a focus mirror having a Polaris collimating mark thereon disposed at a focal point of the objective lens. A time scale cylinder has a time scale thereon and the focus mirror is fixedly mounted within one end portion thereof. The time scale cylinder and the focus mirror can be rotated relative to a month scale cylinder having a date scale and an autumnal equinox point mark thereon, the latter being placed in alignment with a corresponding index provided on the telescope whereby polar axis alignment can be readily achieved with high accuracy.

Abstract: The device comprises a declination adjustable solar ray directed assembly straddling the rim of a circular segment, hinged on the polar axis of an equatorial mount. The circular segment has a holding means for positioning it on the rim of a time dial placed on the equatorial mount. Shoes are attached to the solar directed assembly and ride on the rim of the circular segment, or shoes are attached to a support stand for the equatorial mount and ride on the rim of the equatorial mount. The support stand has a leveling base with two pairs of adjustable legs and pivoted feet providing stiffness in mutually perpendicular planes while allowing for tilting adjustment in alternate planes during the leveling operation.

Abstract: A non-magnetic compass for use in a moving military land vehicle, comprising a rapidly rotating platform having a north star-seeking columnar element that carries a sun-seeking telescope. Fibre optic bundles transmit sun rays from the telescope to a selected light sensor in a stationary circular sensor system concentric with the platform rotational axis. During one instant during each rotating cycle of the platform the telescope will sight the sun while the columnar element is simultaneously oriented to the north star; light rays are transmitted from the scope to a north-oriented sensor in the sensor system. The columnar element and telescope are periodically adjusted to take into account the geographical location of the vehicle and time of year.

Abstract: An electronic sundial apparatus which signals the passage of each hour by a chime, bell or other audible indication and which requires no external source of power other than the sun. Inner and outer concentric hemispheres with vertically extending apertures, specifically slits, configured so as to diverge at their uppermost ends and having a location, length and shape corresponding to the azimuths and distance between the maximum and minimum altitudes of the sun in the sky at each hour throughout the year at predetermined latitudes collimate the sunlight once each hour. The collimated sunlight is detected by a photoelectric cell coupled to a signaling circuit powered by a photovoltaic cell.

Abstract: A solar sight having a scale calibrated in terms of solar declination angle and reflector angle is provided with diffraction pattern forming means comprising a movable sighting tube which, when directed at the sun, provides a Fresnel pattern on a viewing surface, which pattern indicates when said sighting tube is in proper alignment such that its axis is parallel to that of the incoming rays of the sun. The solar sight is portable and may be moved about on a heliostat so as to adjust the operation of the heliostat clock drive to agree with local sun time and to adjust the heliostat reflector tilt angle so that the sun's rays are reflected along or parallel to the polar axis. Movement of the sighting tube causes the movement of a vernier plate bearing an index which permits readout of the solar declination in degrees north or south declination. The vernier scale permits the reading of solar declination angles to 0.1.degree. and the establishment of reflector angles to 0.2.degree..

Abstract: An apparatus for indicating the latitude position of the user is disclosed. The apparatus comprises a base member carrying a scale having degrees of latitude marked on the scale. The base member further carries a scale correcting for the declination of the sun north or south of the equator during days of the year. A vertical member extends perpendicularly upwardly from the base member and carries a means alignable with the current day date when the base member is oriented in a meridian plane and rotated in a vertical plane. When the base member is oriented in a north-south direction and the means aligned to the current date, the end of the shadow cast by the vertical member on the scale of degrees of latitude indicates the latitude position of the user.

Abstract: A device for determining the annual solar exposure of a site which includes a wide angle viewer and a transparent screen having the paths of the sun at various times of year drawn on it, and with the viewer and screen fixed with respect to each other so that when one looks from north toward south through the viewer the paths of the sun at various times of the year are superimposed on the site being investigated.

Abstract: An improved impersonal eyepiece for astronomic positioning is affixed to an optical viewing device to provide a means for observing the position of a celestial object at timed intervals. The viewing device produces a source image of the celestial object and a light source in the eyepiece is energized at timed intervals by a control circuit to illuminate a reticle mask and to thereby superimpose a reticle reference image on the source image during each of the timed intervals. The position of the celestial object with respect to the illuminated reticle is noted during each timed interval and the data so obtained is used to define a reference position.

Abstract: A technique is disclosed herein for evaluating solar exposure at various points in any one of a number of given geographic locations for any given period during the year in order to determine the most efficient location for a solar collector. This technique may be carried out utilizing a single apparatus which is also disclosed herein and which includes a solar pointing device and the necessary indicia to appropriately orient the pointing device with respect to its environment at the various points selected. Once the pointing device is oriented, it is moved in a solar pointing position in an way which determines the path of the sun between sunrise and sunset for each point. From these paths, the amount of actual solar exposure at each of the points selected can be determined taking into account any resulting obstructions such as trees, rooflines or the like.

Abstract: An apparatus to be mounted on conventional sextants permitting faster, more accurate readings with memory storage capability. Alternative transducing means are attached to a sextant arm and generate electronic signals corresponding to amount of rotation of the arm. An electronic timing circuit is coupled to the angle signal generator such that both angle and time may be displayed instantaneously in digital format or stored for later display. Multiple memory circuits allow multiple sextant readings and times to be consecutively taken and stored without requiring separate acts of manual data recordation by the operator after each sighting.

Abstract: The invention disclosed relates to a device for locating celestial bodies by reference to Right Ascension and Declination, and the device is intended to locate using either, R. A. with Declination, or Azimuth with Altitude, or both. However, the use of R. A. and Declination is its primary asset due to the accuracy of its use. The device includes a support platform with orientation indicators, and a pivotal inclined platform is positioned a right ascension-azimuth dial and a right ascension indicator-declination scale piece, both joined about a common axis for rotation. The right ascension indicator-declination scale piece has a support arm disposed thereon for support of a telescope which serves as a viewing means for the celestial body which is located. The device is simply configurated, extremely accurate, and highly effective for use by astronomers generally.

Abstract: An autocollimating assembly is provided for the tracking or position-sensing sub-system of a stellar navigational system, the sub-system being mounted on the stable platform of an inertial measuring unit. The autocollimating assembly, in conjunction with mirrors mounted on the internal surface of the spherical case of the inertial measuring unit permits accelerometer bias, scale factor and alignment measurements to be made, as well as gyro drift and alignment measurements, and sensor alignment for scale factor measurements, with the sub-system installed in the space vehicle. The autocollimating assembly of the invention includes a pattern of point light sources which generate a plurality of light beams which are collimated by the lens system of the sub-system, the beams being reflected back from one of the mirrors on the internal surface of the case of the inertial measuring unit. The reflected light is focused onto the surface of the vidicon or solid state stellar sensor in the sub-system. The angle .theta.

Abstract: This invention provides an improved method and apparatus for celestial navigation. A reference spherical triangle is established from the coordinates of the ground position of an observed selected celestial body and an assumed position for the observer. A second right spherical triangle is then derived from a functional relationship between the first triangle and the observed height of the celestial body. The location of the end of the hypotenuse of the second triangle opposite the ground position defines a point of position on a line of position for the observer. The compass bearing for the line of position is functionally derived from conventional relationships and the line of position may be plotted through the point of position. Plotting means are provided to maintain the spaced relationship between lines of longitude and lines of latitude as a function of latitude for a mercator map projection and to directly plot the point of position on the plotting means.

Abstract: A navigational system for spacecraft use utilizes two telescopes gimbaled on a common axis to measure the scalar angle between a star and the lunar limb. The common axis is the axis of rotation of a momentum wheel carrying a narrow mirror. When each tracker is aligned at its respective target, the mirror passes through the respective optical axis of the telescopes. Timing sensors record the passage to measure the angle and its complement. The phase locked loop used to maintain precision angular rotational rates of the momentum wheel is disclosed such that approximately 20 statistical measurements of the included angle per second can be made.

Abstract: A navigational system for spacecraft utilizes two telescopes gimbaled on a common axis to measure the scalar angle between a star and the lunar limb. The common axis is the axis of rotation of a momentum wheel that carries a light source on it for the generation of timing pulses. This source enhances signal strength by addition of the source generated ray to that received by each telescope. The entire collimated light source is carried by the wheel and the beam is divided equally between telescopes. The collimated rays are imaged by the telescope assembly and this image sweeps across sensor assemblies to generate discrete timing pulses. The trackers employ closed-loop servo systems to center on respective targets and utilize torque motors to drive the trackers relative to the measurement head case.

Abstract: Stellar events are timed through a lens system and reticle by a photomultiplier tube, times are compared and a difference factor computed, the difference factor is implemented to move the lens system, reticle and photomultiplier until times are equal, verifying the location of a line on the reticle to be on the meridian.

Abstract: An improved sextant which provides a very accurate angular measurement of the position of a celestial body relative to the horizon. The sextant is a typical prior art sextant having a horizon glass and an index mirror, and wherein the sextant is sighted by adjusting the angular position of the index mirror to align an image of the celestial body with a sighting of the horizon. An angular position encoder is coupled to the index mirror to provide a digital electrical output signal indicative of the exact angular position of the index mirror. The sextant includes an electrical clock for producing an electrical output signal which indicates the exact time the sighting is taken. The sextant includes electronics for automatically synchronizing the electrical output signal from the encoder with the electrical output signal from the clock.