Physical properties of five near-Earth asteroids within the NEOROCKS project
Year: 2024
Type: article
Abstract: ABSTRACT We present photometric data of five near-Earth asteroids (NEAs) obtained in the framework of the NEO Rapid Observation, Characterization, and Key Simulations (NEOROCKS) project. The selected asteroids are (351545) 2005 TE15, (438908) 2009 XO, (501647) 2014 SD224, 2015 FC35, and 2016 CO247. Light curves were obtained for all the asteroids using the 0.46-m TAR2 telescope at the Teide Observatory (OT), and spectrophotometric data in g, r, i, z$_s$ filters were obtained for asteroids (438908) 2009 XO and (501647) 2014 SD224 using the MuSCAT-2 instrument attached to the 1.52-m Carlos Sanchez Telescope also at the OT. We derived the rotational period of the five NEAs using Fourier series analysis of the rotational light curves. We found $P = 10.6035 \pm 0.0010$ h for (351545) 2005 TE15, $7.9140 \pm 0.006$ h for (501647) 2014 SD224, $3.4211 \pm 0.0075$ h for 2015 FC35, and $4.800 \pm 0.005$ h for 2016 CO247. We observed two periodic variations for (438908) 2009 XO, a long one with two possible periods of $P_1 = 157.2 \pm 0.4$ h and $P_2 = 304.0 \pm 0.4$ h and a large amplitude of 0.881 mag, and a short one with a period of $P = 13.448 \pm 0.008$ h. Radar data suggest that (438908) 2009 XO could be a contact binary and its double period points towards a non-principal axis rotator. Finally, we used the spectrophotometric data to obtain colours and taxonomic classification for (438908) 2009 XO and (501657) 2014 SD224, concluding that both NEAs are S-type objects.
Institutions: Universidad de La Laguna, Instituto de Astrofísica de Canarias, University of Bucharest, Romanian Academy, University of Amsterdam, University of Central Florida, Arecibo Observatory, California Institute of Technology, Jet Propulsion Laboratory, University of Helsinki, Colorado School of Mines, Universities Space Research Association, Lunar and Planetary Institute
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,012
Funders: National Aeronautics and Space Administration, European Commission, Unitatea Executiva pentru Finantarea Invatamantului Superior, a Cercetarii, Dezvoltarii si Inovarii, Agencia Canaria de Investigación, Innovación y Sociedad de la Información, College of Liberal Arts and Social Sciences, University of North Texas, European Regional Development Fund
Awards: BACKGROUND: THE MIT-HAWAII NEAR EARTH OBJECT SURVEY (MITHNEOS) HAS BEEN SYSTEMATICALLY MEASURING NEO NEAR-INFRARED SPECTRA USING SPEX ON THE 3-METER NASA IRTF SINCE 2000. SINCE INCEPTION THIS PROGRAM HAS MEASURED NEAR-INFRARED SPECTRA OF OVER 700 NEAR-EARTH OBJECTS. WE HAVE OBSERVED ~3% OF THE KNOWN DELTA-V<7 KM/S POPULATION REPRESENTING ABOUT 270 NEOS 80 OF WHICH HAVE DELTA-V<6 KM/S. THE SURVEY HAS ALSO OBTAINED SPECTRA FOR ~15% OF THE KNOWN PHA POPULATION OR ABOUT 270 OBJECTS. ALL SPECTRAL OBSERVATIONS FROM THIS CAMPAIGN ARE MADE PUBLICLY AVAILABLE FOR THE COMMUNITY SHORTLY AFTER OBSERVATION AT HTTP://SMASS.MIT.EDU. OBSERVATIONS AND ANALYSIS FROM THIS PROGRAM HAVE HAD A LARGE IMPACT ON NEO SCIENCE SUCH AS: 1) ENHANCED UNDERSTANDING OF SPACE WEATHERING AND REFRESHING MECHANISMS (VERNAZZA ET AL. 2009 NATURE. BINZEL ET AL. 2010 NATURE DEMEO ET AL. 2014) 2) METEORITE-NEO LINKS AND NEO-MAIN BELT SOURCE REGION LINKS (VERNAZZA ET AL 2008 NATURE. THOMAS C.A.&BINZEL R. P. 2010) 3) CHARACTERIZATION OF EXTREMELY SMALL AND RAPIDLY ROTATING NEOS (POLISHOOK ET AL. 2012) 4) DEVELOPMENT OF TECHNIQUES TO DETERMINE ALBEDO AND SPIN ORIENTATION FROM THERMAL EMISSION PAST 2 MICRONS (RIVKIN ET AL. 2005 MOSKOVITZ ET AL. 2017) AND 5) THE VIS+NEAR-INFRARED SPECTRAL TAXONOMY USED BY THE COMMUNITY TO CLASSIFY ASTEROIDS (DEMEO ET AL. 2009). GOALS AND OBJECTIVES: THE PROGRAMMATIC OBJECTIVE OF THIS WORK IS TO SPECTRALLY CHARACTERIZE LOW DELTA-V NEOS AND PHAS. WE WILL MEASUREM 500 NEOS OVER A 5 YEAR PERIOD INCLUDING 150 LOW DELTA-V AND 150 PHA TARGETS. SCIENCE OBJECTIVES OF THIS PROGRAM ARE: 1) COMPOSITIONAL CHARACTERIZATION THROUGH TAXONOMIC CLASSIFICATION AND MINERALOGIC ANALYSIS 2) ALBEDO ESTIMATES FROM MODELING OF THERMAL EMISSION PAST TWO MICRONS. 3) IDENTIFICATION OF METEORITE ANALOGS 4) CHARACTERIZATION OF THE NEO POPULATION AND SUB-POPULATIONS INCLUDING MISSION ACCESSIBLE (LOW DELTA-VELOCITY TARGETS) POTENTIALLY HAZARDOUS ASTEROIDS (PHAS) AND DORMANT COMETS. 5) ANALYSIS OF THE CHANGE IN COMPOSITION OF THE NEO POPULATION AS A FUNCTION OF SIZE. 6) EXPLORATION OF C-COMPLEX DATA TO IDENTIFY DIAGNOSTIC SPECTRAL CHARACTERISTICS AT NEAR-INFRARED WAVELENGTHS. APPROACH AND METHODOLOGY: TARGET SELECTION WILL BE BASED ON NEOS OBSERVABLE ON REQUESTED NASA IRTF OBSERVING DATES BY SEARCHING AMONG LOW DELTA-V TARGETS AND PHAS. DATA WILL BE REDUCED USING THE AUTOSPEX PIPELINE THAT HAS BEEN CONSISTENTLY USED FOR THIS PROGRAM FOR WELL OVER A DECADE. SPECTRAL CLASSIFICATION WILL BE PERFORMED USING THE BUS-DEMEO CLASSIFICATION SYSTEM. SCIENTIFIC ANALYSIS WILL USE ESTABLISHED TECHNIQUES AND TOOLS WHERE APPROPRIATE SUCH AS PRINCIPAL COMPONENT ANALYSIS THERMAL MODELING OF SPECTRAL EMISSION TAILS MINERALOGICAL MODELING AND SPACE WEATHERING MODELING AND COMPARISON WITH THE RELAB METEORITE DATABASE. RELEVANCE AND APPROPRIATENESS TO SOLAR SYSTEM OBSERVATIONS NEOO: THE PROPOSED WORK IS RELEVANT AND APPROPRIATE TO THE SOLAR SYSTEM OBSERVATIONS NEOO PROGRAM BECAUSE AS THE PROGRAM SPECIFIES WE WILL PERFORM NEW GROUND-BASED OBSERVATIONS OF NEAR EARTH OBJECTS TO CHARACTERIZE THEIR COMPOSITIONS. THIS PROGRAM ALSO SUPPORTS THE NASA HUMAN EXPLORATION AND OPERATIONS MISSION DIRECTORATE IN THAT IT PRIORITIZES OBSERVATIONS OF LOW DELTA VELOCITY ORBITS RELATIVE TO EARTH. BECAUSE THE PROPOSED WORK FOCUSES SOLELY ON THE NEAR EARTH OBJECT POPULATION THE NEOO PROGRAM ELEMENT IS THE MOST APPROPRIATE. THE OBSERVATIONS AND OBJECTIVES OF THIS PROGRAM CANNOT BE ACHIEVED BY CURRENT SPACECRAFT MISSIONS., G1601294828, EARTH IS OCCASIONALLY STRUCK BY AN ASTEROID OR COMET LARGE ENOUGH TO CAUSE A SIGNIFICANT EXPLOSION AND LOSS OF LIFE. THE MOST LIKELY IMPACT IS BY A RELATIVELY SMALL OBJECT AND THE BEST MITIGATION STRATEGY MAY SIMPLY BE TO MOVE PEOPLE OUT OF THE WAY. WITH ENOUGH WARNING A SMALL ASTEROID IMPACT WOULD NOT CAUSE LOSS OF LIFE AND PORTABLE PROPERTY MIGHT EVEN BE PRESERVED. WE HAVE BUILT AN "EARLY WARNING" SYSTEM THAT PROVIDES A THREE WEEK NOTICE OF MOST 140M ASTEROIDS OR COMETS ON TRACK TO HIT THE EARTH AND A WEEK'S NOTICE FOR MOST 50M ASTEROIDS. THE SYSTEM HAS BEEN DESIGNED BUILT AND BROUGHT INTO OPERATION IN LESS THAN THREE YEARS AND IS EASILY REPLICABLE. THE "ASTEROID TERRESTRIAL-IMPACT LAST ALERT SYSTEM" (ATLAS) CURRENTLY COMPRISES TWO OBSERVATORIES SEPARATED BY ABOUT 100KM THAT CAN SCAN THE ENTIRE VISIBLE SKY MORE THAN TWICE A NIGHT TO MAGNITUDE 20. SOFTWARE AUTOMATICALLY REGISTERS COMPARISONS WITH THE UNCHANGING SKY AND IDENTIFIES EVERYTHING THAT HAS MOVED OR CHANGED. COMMUNICATION BETWEEN THE OBSERVATORIES AND THE IAU MINOR PLANET CENTER LOCKS DOWN THE ORBIT OF ANYTHING APPROACHING THE EARTH. THIS PROPOSAL SEEKS FUNDING TO CONTINUE OPERATIONS OF THE TWO ATLAS UNITS ALREADY BUILT AND TO CONSTRUCT TWO MORE UNITS FOR THE SOUTHERN HEMISPHERE. ATLAS IS COMPLEMENTARY TO MANY EXISTING SURVEYS FOR NEAR-EARTH OBJECTS (NEOS) BY VIRTUE OF BEING ALL-SKY: IT CAN DETECT MOST 140M NEOS THAT PASS WITHIN 0.1AU OF THE EARTH. ATLAS MAY FIND MORE THAN 500 NEOS PER YEAR EVEN THOUGH ITS FORTE IS DISCOVERY OF THE SUBSET OF NEOS THAT PASS VERY CLOSE TO THE EARTH. ITS STEADY SKY COVERAGE IS ALSO VALUABLE FOR DISCOVERY OF LOW DELTA-V ASTEROIDS CANDIDATE TARGETS FOR A MANNED MISSION. FURTHERMORE ATLAS WILL CHARACTERIZE THE NEO POPULATION AND ALL THE OTHER OBJECTS IT DETECTS BY OBTAINING HUNDREDS OF LIGHT CURVE POINTS PER YEAR THAT WILL ENABLE THE DETERMINATION OF THEIR SHAPE AND SPIN AND ALSO BY OBTAINING SIMULTANEOUS COLOR MEASUREMENTS. OBJECTIVES: ATLAS WILL 1) PROVIDE WARNING THAT IS USEFUL ON A CIVIL DEFENSE TIMESCALE FOR THE MAJORITY OF EARTH-IMPACTING ASTEROIDS OF 50M SIZE OR LARGER 2) REDISCOVER 50% OF ALL 1000M NEOS AND POTENTIALLY HAZARDOUS OBJECTS (PHO) WITHIN 1 YEAR 70% IN 3 YEARS AND 90% IN 10 YEARS DISCOVER MORE THAN 400 NEOS AND 100 PHOS PER YEAR OF 140M SIZE OR LARGER 3) DETECT ABOUT ONE SMALL ASTEROID PER YEAR THAT HITS THE EARTH 4) DISCOVER LOW DELTA-V ASTEROIDS 5) ENABLE SHAPE AND SPIN CALCULATIONS FROM HUNDREDS OF OBSERVATIONS PER YEAR OF THOUSANDS OF ASTEROIDS AND 6) DETECT ALL PLUTO-SIZED OBJECTS WITHIN A DISTANCE OF 120 AU. METHODS: WE HAVE BUILT A PAIR OF SMALL OBSERVATORIES EACH WITH AN 0.5M TELESCOPE THAT COVERS 30 SQUARE DEG WITH EACH EXPOSURE AND WE HAVE WRITTEN ALL THE SOFTWARE REQUIRED FOR THEM TO OPERATE WITHOUT HUMAN INTERVENTION. WE ARE CURRENTLY REPORTING ASTEROID AND COMET DETECTIONS TO THE MPC AND AS THE SYSTEM COMES FULLY ONLINE OUR RATE OF DISCOVERY WILL INCREASE BY A FACTOR OF 10. BY BUILDING ANOTHER TWO UNITS IN THE SOUTH AND AT DIFFERENT LONGITUDE WE WILL DOUBLE OUR DETECTION PROBABILITY FOR THE NEXT CHELYABINSKSIZED IMPACTOR. SIGNIFICANCE: THIS PROJECT WORKS TOWARDS ACCOMPLISHING THE CONGRESSIONAL MANDATE TO MITIGATE THE HAZARD FROM EARTH-IMPACTING ASTEROIDS BY FOCUSING ON DETECTION OF NEARLY ALL HAZARDOUS ASTEROIDS IN THE DAYS OR WEEKS BEFORE IMPACT. ALTHOUGH DETECTION IN TIME TO DIVERT DANGEROUS ASTEROIDS IS LAUDABLE IT IS ALSO CURRENTLY UNAFFORDABLE AND ATLAS ADDRESSES THE INTENT OF THE MANDATE BY PROTECTING LIVES. ATLAS WILL AFFORD A YEARLY OPPORTUNITY TO STUDY A METEORITE BEFORE IT STRIKES THE EARTH'S ATMOSPHERE AND WILL PROVIDE MUCH BETTER STATISTICS ON THE POPULATION THAT DOES PASS CLOSE TO THE EARTH. ATLAS WILL DISCOVER LOW DELTA-V ASTEROIDS SUITABLE FOR A MANNED MISSION AND CHARACTERIZATION OF THE SPIN AND SHAPE OF MANY ASTEROIDS MAY PROVE VALUABLE FOR FUTURE MISSIONS., THE ASTEROID TERRESTRIAL-IMPACT LAST ALERT SYSTEM (ATLAS) WAS AWARDED A 5 YEAR GRANT BY NASA NEOO IN 2013 TO CONSTRUCT AND OPERATE WIDE FIELD TELESCOPES THAT ARE CAPABLE OF SCANNING THE ENTIRE SKY EACH NIGHT TO MAGNITUDE 20. THE PARTICULAR STRENGTH OF ATLAS IS TO BE COMPLEMENTARY TO LARGER TELESCOPES SUCH AS PAN-STARRS AND CATALINA - ATLAS COVERS MUCH MORE AREA EACH NIGHT TO A SHALLOWER DEPTH. ATLAS IS DESIGNED TO BE AN "EARLY WARNING" SYSTEM THAT WILL PROVIDE THREE WEEKS' NOTICE OF MOST 140M ASTEROIDS OR COMETS ON TRACK TO HIT THE EARTH AND A WEEK'S NOTICE FOR MOST 50M ASTEROIDS. WE HAVE COMPLETED TWO ATLAS UNITS AND INSTALLED THEM ON HALEAKALA AND MAUNA LOA IN HAWAII. THE TELESCOPES OPERATE COMPLETELY ROBOTICALLY EACH NIGHT AND THROUGHOUT THE NIGHT THE DATA ARE REDUCED IN REAL-TIME ON EACH SUMMIT AND ANALYZED FOR CANDIDATE NEAR-EARTH ASTEROIDS. IN THE MORNING A HUMAN REVIEWER VERIFIES THE NEW ASTEROIDS IN THE NIGHTLY PROCESSING AND SUBMITS ASTROMETRY TO THE IAU MINOR PLANET CENTER. WE OBSERVE ABOUT HALF THE VISIBLE SKY EACH NIGHT FIVE TIMES WITH THE TWO-TELESCOPE SYSTEM BUT AT REDUCED SENSITIVITY DUE TO IMPROPERLY FIGURED SCHMIDT CORRECTORS ON THE TELESCOPES. REPLACEMENT LENSES FROM A DIFFERENT VENDOR ARE EXPECTED TO BE INSTALLED IN APRIL 2017 IMPROVING THE SENSITIVITY OF THE SYSTEM FROM M~19 TO THE DESIGNED CAPABILITY OF M~20 AND INCREASING THE DISCOVERY RATE BY MORE THAN 5X. TO DATE IN EARLY 2017 ATLAS HAS DISCOVERED 34 NEAS AND 5 PHAS SINCE START OF OPERATIONS. EXCEPT FOR DELAYS DUE TO THE SCHMIDT CORRECTORS ALL OTHER ASPECTS OF THE BUILD CONSTRUCTION AND COMMISSIONING OF BOTH THE HARDWARE AND SOFTWARE PROJECTS HAVE BEEN ON-TIME AND ON-BUDGET. WE ARE PROPOSING TO BUILD TWO MORE IDENTICAL "ATLAS UNITS" AND DEPLOY THEM AT THE BEST SITES POSSIBLE. WE EXPECT THAT THESE SITES WILL BE SAAO IN SOUTH AFRICA AND CHILE BUT WE WILL PERFORM A COMPETITIVE SEARCH FOR ALTERNATE SITES ONCE THE PROPOSAL IS FUNDED. BECAUSE OF THE DIVERSITY IN LATITUDE LONGITUDE AND WEATHER THESE TWO ADDITIONAL UNITS SHOULD DOUBLE THE ATLAS DISCOVERY RATE OF THE MOST PERNICIOUS PHAS - THE 20-50M ASTEROIDS THAT PASS VERY CLOSE TO THE EARTH AND ARE ONLY VISIBLE TO ANY TELESCOPE FOR A SHORT TIME., G4800998230, WE PROPOSE HERE TO CARRY OUT RAPID RESPONSE NEAR-INFRARED SPECTROPHOTOMETRIC CHARACTERIZATION OF HUNDREDS OF NEOS EACH YEAR. THIS TECHNIQUE IS POWERF, G5482801873, G677328955, The NEO Rapid Observation, Characterization and Key Simulations, NEAR-EARTH OBJECTS (NEOS) ARE ESSENTIAL TO UNDERSTANDING THE ORIGIN OF THE SOLAR SYSTEM THROUGH THEIR COMPOSITIONAL LINKS TO METEORITES. AS TRACERS OF OTHER PARTS OF THE SOLAR SYSTEM THEY PROVIDE INSIGHT TO MORE DISTANT POPULATIONS. THEIR RELATIVELY SMALL SIZES AND COMPLEX DYNAMICAL HISTORIES MAKE THEM EXCELLENT LABORATORIES FOR STUDYING ONGOING SOLAR SYSTEM PROCESSES SUCH AS SPACE WEATHERING PLANETARY ENCOUNTERS AND NON-GRAVITATIONAL DYNAMICS. KNOWLEDGE OF THEIR PHYSICAL PROPERTIES IS ESSENTIAL TO IMPACT HAZARD ASSESSMENT. FINALLY THE PROXIMITY OF NEOS TO EARTH MAKE THEM FAVORABLE TARGETS FOR ROBOTIC AND HUMAN EXPLORATION.HOWEVER IN SPITE OF THEIR SCIENTIFIC IMPORTANCE ONLY THE LARGEST NEOS HAVE BEEN WELL STUDIED AND A REPRESENTATIVE SAMPLE OF PHYSICAL CHARACTERISTICS FOR SUB-KM NEOS DOES NOT EXIST.WE PROPOSE HERE FOR SUPPORT OF THE MISSION ACCESSIBLE NEAR-EARTH OBJECT SURVEY (MANOS). MANOS IS A FULLY ALLOCATED MULTI-YEAR SURVEY OF SUB-KM NEOS THAT IS READY TO PROVIDE A LARGE UNIFORM CATALOG OF PHYSICAL PROPERTIES (LIGHT CURVES + COLORS + SPECTRA + ASTROMETRY) REPRESENTING A 100-FOLD INCREASE OVER PRESENT KNOWLEDGE OF NEOS IN THIS SIZE RANGE. FROM THIS COMPREHENSIVE CATALOG WE WILL DERIVE GLOBAL PROPERTIES OF THE NEO POPULATION AS WELL AS IDENTIFY INDIVIDUAL TARGETS THAT ARE OF POTENTIAL INTEREST FOR EXPLORATION.WE WILL ACCOMPLISH THESE GOALS FOR APPROXIMATELY 500 MISSION-ACCESSIBLE NEOS ACROSS THE VISIBLE AND NEAR-INFRARED RANGES USING TELESCOPE ASSETS IN BOTH THE NORTHERN AND SOUTHERN HEMISPHERES. MANOS HAS ALREADY BEEN AWARDED OR IS GUARANTEED TIME ON 10 DIFFERENT TELESCOPES RANGING IN APERTURE FROM 1 TO 8 METERS AND WILL GRADUALLY BEGIN IN LATE 2013 WITH FULL OPERATIONS ESTABLISHED BY MID-2014. WE WILL USE PROVEN ANALYSIS TOOLS TO MODEL AND CHARACTERIZE EACH OF THE OBJECTS OBSERVED BY MANOS. WE WILL CONDUCT THIS SURVEY WITH COMPLETE TRANSPARENCY SHARING OUR TARGET LISTS AND DATA PRODUCTS ON PUBLICLY-ACCESSIBLE WEBSITES.A REPRESENTATIVE SAMPLE OF MORE THAN 500 LARGE KM-SCALE NEOS HAS ALREADY BEEN OBTAINED. THE FRONTIER OF NEO RESEARCH INVOLVES PUSHING OBSERVATIONAL LIMITS TO BUILD AN EQUIVALENT REPRESENTATIVE DATABASE OF THE SMALLEST NEOS. MANOS REPRESENTS THIS NEXTGENERATION OF NEO SURVEYS MADE POSSIBLE BY ESTABLISHING A REGULAR CADENCE OF OBSERVATIONS TO ACCESS SMALL NEWLY DISCOVERED NEOS WITHIN DAYS OR WEEKS OF FIRST DETECTION BEFORE THEY FADE BEYOND OBSERVATIONAL LIMITS.MANOS WILL ADDRESS THE FOLLOWING KEY TOPICS RELEVANT TO PLANETARY SCIENCE AND EXPLORATION:- COMPOSITIONAL DISCREPANCIES BETWEEN KM-SCALE NEOS AND METEORITES- SPACE WEATHERING PROCESSES BY TARGETING SMALL OBJECTS THAT ARE DYNAMICALLY YOUNG AND THAT UNDERGO FREQUENT SURFACE-RESETTING PLANETARY ENCOUNTERS- THE INFLUENCE OF PLANETARY ENCOUNTERS ON NEO ROTATIONAL PROPERTIES- THE NEO BINARY RATE AND TIDAL FORMATION OF BINARY SYSTEMS- RADIATIVE TRANSFER OF REGOLITH-COVERED SURFACES BY ACCESSING OBJECTS ACROSS A RANGE OF VIEWING ASPECTS- DETERMINING PHYSICAL CRITERIA FOR PLANNING OF ROBOTIC AND HUMAN EXPLORATION MISSIONS
OpenAlex ID: W4403714066