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1 + View the NASA Portal + Near-Earth Object (NEO) Project Search JPL HORIZONS Web-Interface This tool provides a web-based limited interface to JPL's HORIZONS system which can be used to generate ephemerides for solar-system bodies. Full access to HORIZONS features is available via the primary telnet interface. HORIZONS system news shows recent changes and improvements. A web-interface tutorial is available to assist new users. Current Settings Ephemeris Type [change] : OBSERVER Target Body [change] : Asteroid (2002 AQ3) Observer Location [change] : Cerro Tololo Observatory, La Serena [807] ( '38.8''E, 30 10'08.9''S, m ) Time Span [change] : Start= :00, Stop= :00, Step=15 m Table Settings [change] : QUANTITIES=1,4,8-10,13,23-25; skip daylight=yes Display/Output [change] : default (formatted HTML) Object Data Page JPL/HORIZONS (2002 AQ3) 2010-Aug-27 00:16:29 Rec #: (+COV) Soln.date: 2010-Jul-22_01:50:20 # obs: 143 ( ) FK5/J helio. ecliptic osc. elements (AU, DAYS, DEG, period=julian yrs): EPOCH= ! 2006-Jun (CT) Residual RMS= EC= QR= TP= OM= W= IN= A= MA= ADIST= PER= N= ANGMOM= DAN= DDN= L= B= TP= 2007-Sep Physical parameters (KM, SEC, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= G=.150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ASTEROID comments: 1: soln ref.= JPL#37, OCC=0 2: source=orb Results Ephemeris / WWW_USER Fri Aug 27 00:16: Pasadena, USA / Horizons Target body name: (2002 AQ3) {source: JPL#37} Center body name: Earth (399) Center-site name: Cerro Tololo Observatory, La Serena Start time : A.D Aug-30 22:00: UT Stop time : A.D Aug-31 22:00: UT Step-size : 15 minutes Target pole/equ : No model available Target radii : (unavailable) Center geodetic : , , {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: , , {E-lon(deg),Dxy(km),Dz(km)} Center pole/equ : High-precision EOP model {East-longitude +} Center radii : x x km {Equator, meridian, pole} Target primary : Sun Interfering body: MOON (Req= ) km Deflecting body : Sun, EARTH Deflecting GMs : E+11, E+05 km^3/s^2 Small perturbers: Ceres, Pallas, Vesta {source: SB405-CPV-2} Small body GMs : 6.32E+01, 1.43E+01, 1.78E+01 km^3/s^2 Atmos refraction: NO (AIRLESS) RA format : HMS Time format : CAL 1 of 4 8/27/10 12:19 AM

2 RTS-only print : NO EOP file : eop p EOP coverage : DATA-BASED 1962-JAN-20 TO 2010-AUG-26. PREDICTS-> 2010-NOV-16 Units conversion: 1 AU= km, c= km/s, 1 day= s Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (YES) Table cut-offs 2: Solar Elongation ( 0.0,180.0=NO ) Initial FK5/J heliocentric ecliptic osculating elements (AU, DAYS, DEG): EPOCH= ! 2006-Jun (CT) Residual RMS= EC= QR= TP= OM= W= IN= Asteroid physical parameters (KM, SEC, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= G=.150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ************************************************** Date (UT) HR:MN R.A._(ICRF/J2000.0)_DEC Azi_(a-appr)_Elev a-mass APmag Illu% Ang-diam S-O-T /r S-T-O T-O-M/Illu% ************************************************** $$SOE >... Daylight Cut-off Requested...< 2010-Aug-30 22:30 C n.a /T / Aug-30 22:45 C n.a /T / Aug-30 23:00 N n.a /T / Aug-30 23:15 N n.a /T / Aug-30 23:30 A n.a /T / Aug-30 23:45 A n.a /T / Aug-31 00: n.a /T / Aug-31 00: n.a /T / Aug-31 00: n.a /T / Aug-31 00: n.a /T / Aug-31 01: n.a /T / Aug-31 01: n.a /T / Aug-31 01: n.a /T / Aug-31 01: n.a /T / Aug-31 02: n.a /T / Aug-31 02: n.a /T / Aug-31 02: n.a /T / Aug-31 02:45 t n.a /T / Aug-31 03: n.a /T / Aug-31 03: n.a /T / Aug-31 03: n.a /T / Aug-31 03: n.a /T / Aug-31 04: n.a /T / Aug-31 04:15 m n.a /T / Aug-31 04:30 m n.a /T / Aug-31 04:45 m n.a /T / Aug-31 05:00 m n.a /T / Aug-31 05:15 m n.a /T / Aug-31 05:30 m n.a /T / Aug-31 05:45 m n.a /T / Aug-31 06:00 m n.a /T / Aug-31 06:15 m n.a /T / Aug-31 06:30 m n.a /T / Aug-31 06:45 m n.a /T / Aug-31 07:00 m n.a /T / Aug-31 07:15 m n.a /T / Aug-31 07:30 m n.a /T / Aug-31 07:45 m n.a /T / Aug-31 08:00 m n.a /T / Aug-31 08:15 m n.a /T / Aug-31 08:30 m n.a /T / Aug-31 08:45 m n.a /T / Aug-31 09:00 m n.a /T / Aug-31 09:15 m n.a /T / Aug-31 09:30 m n.a /T / Aug-31 09:45 Am n.a /T / Aug-31 10:00 Am n.a /T / Aug-31 10:15 Nm n.a /T / Aug-31 10:30 Nm n.a /T / Aug-31 10:45 Cm n.a /T / 63.2 >... Daylight Cut-off Requested...< $$EOE ************************************************** Column meaning: TIME Prior to 1962, times are UT1. Dates thereafter are UTC. Any 'b' symbol in the 1st-column denotes a B.C. date. First-column blank (" ") denotes an A.D. date. Calendar dates prior to 1582-Oct-15 are in the Julian calendar system. Later calendar dates are in the Gregorian system. The uniform Coordinate Time scale is used internally. Conversion between CT and the selected non-uniform UT output scale has not been determined for UTC times after the next July or January 1st. The last known leap-second is used over any future interval. NOTE: "n.a." in output means quantity "not available" at the print-time. 2 of 4 8/27/10 12:19 AM

3 SOLAR PRESENCE (OBSERVING SITE) Time tag is followed by a blank, then a solar-presence symbol: '*' Daylight (refracted solar upper-limb on or above apparent horizon) 'C' Civil twilight/dawn 'N' Nautical twilight/dawn 'A' Astronomical twilight/dawn ' ' Night OR geocentric ephemeris LUNAR PRESENCE WITH TARGET RISE/TRANSIT/SET MARKER (OBSERVING SITE) The solar-presence symbol is immediately followed by another marker symbol: 'm' Refracted upper-limb of Moon on or above apparent horizon ' ' Refracted upper-limb of Moon below apparent horizon OR geocentric 'r' Rise (target body on or above cut-off RTS elevation) 't' Transit (target body at or past local maximum RTS elevation) 's' Set (target body on or below cut-off RTS elevation) RTS MARKERS (TVH) Rise and set are with respect to the reference ellipsoid true visual horizon defined by the elevation cut-off angle. Horizon dip and yellow-light refraction (Earth only) are considered. Accuracy is < or = to twice the requested search step-size. R.A._(ICRF/J2000.0)_DEC = J astrometric right ascension and declination of target center. Corrected for light-time. Units: HMS (HH MM SS.ff) and DMS (DD MM SS.f) Azi_(a-appr)_Elev = Airless apparent azimuth and elevation of target center. Corrected for light-time, the gravitational deflection of light, stellar aberration, precession and nutation. Azimuth measured North(0) -> East(90) -> South(180) -> West(270) -> North (360). Elevation is with respect to plane perpendicular to local zenith direction. TOPOCENTRIC ONLY. Units: DEGREES a-mass = Relative optical airmass at target center point. Topocentric EARTH sites, ABOVE HORIZON ONLY. Unitless. APmag = Asteroid's approximate apparent visual magnitude by following definition: APmag = H + 5*log10(delta) + 5*log10(r) - 2.5*log10((1-G)*phi1 + G*phi2). In principle, accurate to ~ +/- 0.1 magnitude. For solar phase angles > 90 deg, the error could exceed 1 magnitude. No values are output for phase angles greater than 120 degrees, since the extrapolation error could be large and unknown. Units: NONE Illu% = Fraction of target circular disk illuminated by Sun (phase), as seen by observer. Units: PERCENT Ang-diam = The equatorial angular width of the target body full disk, if it were fully visible to the observer. Units: ARCSECONDS S-O-T /r = Sun-Observer-Target angle; target's apparent solar elongation seen from observer location at print-time. If negative, the target center is behind the Sun. Angular units: DEGREES. The '/r' column is a Sun-relative code, output for observing sites with defined rotation models only. /T indicates target trails Sun (evening sky) /L indicates target leads Sun (morning sky) NOTE: The S-O-T solar elongation angle is the total separation in any direction. It does not indicate the angle of Sun leading or trailing. S-T-O = Sun-Target-Observer (~ PHASE ANGLE) angle: the vertex angle at target center formed by a vector to the apparent center of the Sun and a vector intersecting the observer at print-time. This measurable angle is within 20 arcseconds (0.006 deg) of the reduced PHASE ANGLE at observer's location at print time. The difference is due to down-leg stellar aberration affecting measured target position but not apparent solar illumination direction. When computing phase, Horizons uses the true phase angle, not S-T-O, but the resulting difference in illuminated fraction is less than 0.001%. Units: DEGREES T-O-M/Illu% = Target-Observer-Moon/Illuminated percentage. The apparent lunar elongation angle between target body CENTER and the Moon's CENTER, seen from the observing site, along with fraction of the lunar disk illuminated by the Sun. A negative lunar elongation angle indicates the target center is behind the Moon. Units: DEGREES & PERCENT. Computations by... Solar System Dynamics Group, Horizons On-Line Ephemeris System 3 of 4 8/27/10 12:19 AM

4 4800 Oak Grove Drive, Jet Propulsion Laboratory Pasadena, CA USA Information: Connect : telnet://ssd.jpl.nasa.gov:6775 (via browser) telnet ssd.jpl.nasa.gov 6775 (via command-line) Author : Jon.Giorgini@jpl.nasa.gov ************************************************** 2010-Aug-27 07:16 UT (server date/time) Site Manager: Donald K. Yeomans Webmaster: Alan B. Chamberlin 4 of 4 8/27/10 12:19 AM

5 Minor Planet Ephemeris Service: Query Results Minor Planet Ephemeris Service: Query Results Below are the results of your request from the Minor Planet Center's Minor Planet Ephemeris Service. Ephemerides are for observatory code 807. You have selected suppression of ephemeris data when objects are below, or the sun is above, your local horizon. (159609) 2002 AQ3 Display all designations for this object / # of variant orbits available = 11 Epoch 2010 July 23.0 TT = JDT MPC M (2000.0) P Q n Peri T = JDT a Node q = e Incl Earth MOID = AU P 3.07 H 17.0 G 0.15 U 1 From 126 observations at 5 oppositions, , mean residual 0".49. Last observed on 2010 July 18. Perturbed ephemeris below based on elements from MPO Discovery date : Discovery site : Palomar Discoverer(s) : NEAT Further observations? NEO : Not necessary at first ephemeris date F9609 Date UT R.A. (J2000) Decl. Delta r El. Ph. V Coord Motion Object Sun Moon Uncertainty i h m s "/min "/min Azi. Alt. Alt. Phase Dist. Alt. 3-sig/" P.A M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M... Suppressed M M M M M M M M M M M M M M M M M M 1 of 2 8/27/10 12:18 AM

6 Minor Planet Ephemeris Service: Query Results M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M... Suppressed... This service has been made possible by Process Software Corporation, and their excellent VMS Web server, Purveyor. These calculations have been performed on the Tamkin Foundation Computing Network. 2 of 2 8/27/10 12:18 AM