WE PROPOSE TO CONTINUE OUR PROJECT DEDICATED TO NEO CONFIRMATION AND FOLLOW-UP WHICH WAS STARTED IN 2013. AS SUCH IT SUPPORTS NASA'S MISSION TO DISCOVER AND CATALOGUE 90% OF THE POTENTIALLY HAZARDOUS NEOS WITH DIAMETERS LARGER THAN 100 M BY PROVIDING TIME-CRITICAL CONFIRMATION AND FOLLOW-UP ASTROMETRIC OBSERVATIONS. IN ADDITION TO ASTROMETRY WE WILL ALSO PROVIDE CATALOG-BASED BRIGHTNESS ESTIMATES FOR APPROXIMATE SIZE DETERMINATION. WE WILL IMPROVE ON PREVIOUS DATA BY UTILIZING A NEW INSTRUMENT OF MCDONALD OBSERVATORY A PROEM 1024B UNIT MOUNTED AT THE PRIME FOCUS OF THE 2.1 M OTTO STRUVE TELESCOPE. OUR ACCURATE ASTROMETRIC OBSERVATIONS WILL CONTRIBUTE TO: (1) DETERMINING ORBITS FOR NEWLY DISCOVERED OBJECTS AT A CONFIDENCE LEVEL SUITABLE TO ASSIGN AN MINOR PLANET CENTER (MPC) PROVISIONAL DESIGNATION (2) MAINTAINING ORBIT ACCURACY FOR UNDER-OBSERVED MINOR PLANETS TO SUPPORT LONG-TERM TRACKING WITH SPECIAL EMPHASIS ON VIRTUAL IMPACTORS AND OBJECTS DOWN TO 100M IN SIZE (3) PROVIDE BRIGHTNESS MEASUREMENTS IN R FOR INITIAL SIZE ESTIMATION. ALL THREE ASPECTS ARE CRITICAL FOR OBTAINING FUTURE DATA FOR PHYSICAL CHARACTERIZATION OF THE NEA POPULATION. WE WILL CONDUCT OBSERVATIONS WITH THE PROEM 1024B CAMERA AS AN IMAGING INSTRUMENT WITH AUTOGUIDER OPTION. THE INSTRUMENT HAS A 5.6 ARCMINUTE SQUARE FIELD OF VIEW. THIS PROVIDES A 40% INCREASE IN THE AREA OF SKY COVERED. HAVING ACCESS TO MORE REFERENCE STARS WILL MAKE OUR ASTROMETRIC SOLUTION MORE ROBUST. THE PIXEL SIZE IS SLIGHTLY LARGER (0.33 ARCSECOND PIXELS) BUT THE BEST SEEING MEASURED AT THE TELESCOPE WAS AROUND 0.6 ARCSECONDS AT ZENITH. THE TELESCOPE S RA DRIVE HAS BEEN RECENTLY UPDATED USING A CLOSED-LOOP SYSTEM. THIS BY ITSELF REDUCES THE 2 ARCMINUTE PERIODIC TRACKING ERROR OF THE TELESCOPE TO ABOUT 0.2 RMS IN WINDY CONDITIONS. WE WILL HAVE THE OPTION OF EITHER TRACKING THE ASTEROID IN RA OR USE AUTOGUIDING ON STARS FOR IMAGE STACKING. GOING TO PRIME FOCUS (I.E. ELIMINATING THE SECONDARY OF THE TELESCOPE AND THE FOCAL REDUCER) GAINS US AT LEAST ONE MAGNITUDE ALLOWING US TO REDUCE EXPOSURE TIMES AND GET BETTER SIGNAL TO NOISE ON FAINTER FASTER-MOVING TARGETS. UNDER IDEAL SKY WE ACHIEVE 23.5 MAGNITUDE IN THE RED WITH 180-SECOND EXPOSURE TIMES ON OBJECTS MOVING AT SIDEREAL RATES. WE WILL PROVIDE IMPROVED ASTROMETRIC POSITIONS FOR NEOS OF SPECIAL INTEREST. USING USNO ASTROMETRIC CATALOGUES WE REDUCE THE DATA ON SITE AND THE CONFIRMATION OBSERVATIONS ARE TRANSMITTED IMMEDIATELY TO THE MPC. REGULAR FOLLOW-UP DATA ARE SUBMITTED IN THE MORNING. DURING THE FOUR YEARS OF OUR PREVIOUS GRANT (2012-2016) UTILIZING THE SAME TELESCOPE WE HAVE SUBMITTED 2667 OBSERVATION TO THE IAU MPC. OF THOSE 90% HAD A RESIDUAL LESS THAN 1 ARCSECOND AND 98% WERE WITHIN 2 ARCSECONDS WITH RESPECT TO THE BEST FITTING ORBIT DETERMINED BY THE MPC. ONLY 25 WERE REJECTED DUE TO BEING MARGINAL DATA. WITH IMPROVED TRACKING THE ASTROMETRIC PRECISION OF OUR STACKED IMAGES WILL BE IMPROVED BY AN ESTIMATED 50% AND WITH FAINTER LIMITING MAGNITUDE WE WILL CONFIRM OBJECTS ABOUT A MAGNITUDE FAINTER THEN BEFORE.
$253,358FY2017National Aeronautics and Space AdministrationNASA
University Of Texas At Austin, Austin TX