Finding Near Earth Objects
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Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar End
N9 Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar end Planetary Laboratory The University of Arizona Our overall scientific goal is to survey the solar system to completion -- that is, to find the various populations and to study their statistics, interrelations, and origins. The practical benefit to SERC is that we are finding Earth-approaching asteroids that are accessible for mining. Our system can detect Earth-approachers In the 1-km size range even when they are far away, and can detect smaller objects when they are moving rapidly past Earth. Until Spacewatch, the size range of 6 - 300 meters in diameter for the near-Earth asteroids was unexplored. This important region represents the transition between the meteorites and the larger observed near-Earth asteroids (Rabinowitz 1992). One of our Spacewatch discoveries, 1991 VG, may be representative of a new orbital class of object. If it is really a natural object, and not man-made, its orbital parameters are closer to those of the Earth than we have seen before; its delta V is the lowest of all objects known thus far (J. S. Lewis, personal communication 1992). We may expect new discoveries as we continue our surveying, with fine-tuning of the techniques. III-12 Introduction The data accumulated in the following tables are the result of continuing observation conducted as a part of the Spacewatch program. T. Gehrels is the Principal Investigator and also one of the three observers, with J.V. Scotti and D.L Rabinowitz, each observing six nights per month. R.S. McMillan has been Co-Principal Investigator of our CCD-scanning since its inception; he coordinates optical, mechanical, and electronic upgrades. -
The Catalina Sky Survey
The Catalina Sky Survey Current Operaons and Future CapabiliKes Eric J. Christensen A. Boani, A. R. Gibbs, A. D. Grauer, R. E. Hill, J. A. Johnson, R. A. Kowalski, S. M. Larson, F. C. Shelly IAWN Steering CommiJee MeeKng. MPC, Boston, MA. Jan. 13-14 2014 Catalina Sky Survey • Supported by NASA NEOO Program • Based at the University of Arizona’s Lunar and Planetary Laboratory in Tucson, Arizona • Leader of the NEO discovery effort since 2004, responsible for ~65% of new discoveries (~46% of all NEO discoveries). Currently discovering NEOs at a rate of ~600/year. • 2 survey telescopes run by a staff of 8 (observers, socware developers, engineering support, PI) Current FaciliKes Mt. Bigelow, AZ Mt. Lemmon, AZ 0.7-m Schmidt 1.5-m reflector 8.2 sq. deg. FOV 1.2 sq. deg. FOV Vlim ~ 19.5 Vlim ~ 21.3 ~250 NEOs/year ~350 NEOs/year ReKred FaciliKes Siding Spring Observatory, Australia 0.5-m Uppsala Schmidt 4.2 sq. deg. FOV Vlim ~ 19.0 2004 – 2013 ~50 NEOs/year Was the only full-Kme NEO survey located in the Southern Hemisphere Notable discoveries include Great Comet McNaught (C/2006 P1), rediscovery of Apophis Upcoming FaciliKes Mt. Lemmon, AZ 1.0-m reflector 0.3 sq. deg. FOV 1.0 arcsec/pixel Operaonal 2014 – currently in commissioning Will be primarily used for confirmaon and follow-up of newly- discovered NEOs Will remove follow-up burden from CSS survey telescopes, increasing available survey Kme by 10-20% Increased FOV for both CSS survey telescopes 5.0 deg2 1.2 ~1,100/ G96 deg2 night 19.4 deg2 2 703 8.2 deg 2 ~4,300 deg per night New 10k x 10k cameras will increase the FOV of both survey telescopes by factors of 4x and 2.4x. -
An Early Warning System for Asteroid Impact
An Early Warning System for Asteroid Impact John L. Tonry(1) ABSTRACT Earth is bombarded by meteors, occasionally by one large enough to cause a significant explosion and possible loss of life. It is not possible to detect all hazardous asteroids, and the efforts to detect them years before they strike are only advancing slowly. Similarly, ideas for mitigation of the danger from an impact by moving the asteroid are in their infancy. Although the odds of a deadly asteroid strike in the next century are low, the most likely impact is by a relatively small asteroid, and we suggest that the best mitigation strategy in the near term is simply to move people out of the way. With enough warning, a small asteroid impact should not cause loss of life, and even portable property might be preserved. We describe an \early warning" system that could provide a week's notice of most sizeable asteroids or comets on track to hit the Earth. This may be all the mitigation needed or desired for small asteroids, and it can be implemented immediately for relatively low cost. This system, dubbed \Asteroid Terrestrial-impact Last Alert System" (AT- LAS), comprises two observatories separated by about 100 km that simulta- neously scan the visible sky twice a night. Software automatically registers a comparison with the unchanging sky and identifies everything which has moved or changed. Communications between the observatories lock down the orbits of anything approaching the Earth, within one night if its arrival is less than a week. The sensitivity of the system permits detection of 140 m asteroids (100 Mton impact energy) three weeks before impact, and 50 m asteroids a week be- fore arrival. -
Neofixer a Broker for Near Earth Asteroid Follow-Up Rob Seaman & Eric Christensen Catalina Sky Survey
NEOFIXER A BROKER FOR NEAR EARTH ASTEROID FOLLOW-UP ROB SEAMAN & ERIC CHRISTENSEN CATALINA SKY SURVEY Building the Infrastructure for Time-Domain Alert Science in the LSST Era • May 22-25, 2017 • Tucson CATALINA SKY SURVEY • LPL runs 2 NEO projects, CSS and SpacewatcH • Talk to Eric or me about CSS, Bob McMillan for SW • CSS demo at 3:30 pm CONGRESSIONAL MANDATE • Spaceguard goal: 1 km Near EartH Objects ✔ • George E Brown Act to find > 140m (H < 22) NEOs • 90% complete by 2020 ✘ (2017: ~ 30%) • ROSES 2017 language is > 100m • Chelyabinsk was ~20m (H ~ 25.8) or ~400 kiloton (few per century likeliHood) SUMMARY • Near EartH Asteroid inventory is “retail Big Data” • NEOfixer will be NEO-optimized targeting broker • No one broker will address all use cases • Will benefit LSST as well as current surveys • LSST not tasked to study NEOs, but ratHer tHe Solar System (slower objects and fartHer away) • What is tHe most valuable NEO observation a particular telescope can make at a particular time? CHESLEY & VERES (1705.06209) • 55 ± 5.0% for LSST baseline operating alone • But 42% of NEOs witH H < 22 will be discovered before 2022 • And witHout LSST, current surveys would discover 61% of the catalog by 2032 • Completion CH<22 will be 77% combined LSST will add 16% to CH<22 Can targeted follow-up increase this? CHESLEY & VERES (CAVEATS) • Lots of details worth reading • CH<22 degrades by ~1.8% for every 0.1 mag loss in sensitivity • Issues of linking efficiency including: • Efficiency down to H < 25 is lower • 4% false MBA-MBA links ASTROMETRIC -
Newsletter December 2016
Current NEO statistics A refinement of the method used for analysing the asteroid hazard led to an increase in the number of objects in the risk list. Known NEOs: 15 271 asteroids and 106 comets NEOs in risk list*: 576 New NEO discoveries since last month: 161 NEOs discovered since 1 January 2016: 1750 Focus on Whenever a new set of observations for an object is published, our Impact Monitoring routines perform a new search for possibly impacting orbits compatible with such set of observations. The system is capable of detecting all possibly impacting orbits down to an impact probability threshold, named “generic completeness level”. The search begins by investigating a set of initial conditions taken along a specific line of parameters, called Line of Variations (LoV), inside the orbit uncertainty region. The NEODyS impact monitoring system was recently switched to a new method to sample the LoV, which decreased the generic completeness level from 4×10-7 to 10-7 (i.e. a factor of four better than the previous approach). The whole risk list has been updated with the outcome of the new method, and it is now available on both the NEODyS and the NEOCC risk pages. Upcoming interesting close approaches To date no known object is expected to come closer than one lunar distance to our planet in December, thus deserving special attention. New discoveries likely will. The closest known approach will be 2016 WQ3 at 1.5 lunar distances on 1 December. Recent interesting close approaches Four new objects came closer than the Moon in November. -
Detecting the Yarkovsky Effect Among Near-Earth Asteroids From
Detecting the Yarkovsky effect among near-Earth asteroids from astrometric data Alessio Del Vignaa,b, Laura Faggiolid, Andrea Milania, Federica Spotoc, Davide Farnocchiae, Benoit Carryf aDipartimento di Matematica, Universit`adi Pisa, Largo Bruno Pontecorvo 5, Pisa, Italy bSpace Dynamics Services s.r.l., via Mario Giuntini, Navacchio di Cascina, Pisa, Italy cIMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universits, UPMC Univ. Paris 06, Univ. Lille, 77 av. Denfert-Rochereau F-75014 Paris, France dESA SSA-NEO Coordination Centre, Largo Galileo Galilei, 1, 00044 Frascati (RM), Italy eJet Propulsion Laboratory/California Institute of Technology, 4800 Oak Grove Drive, Pasadena, 91109 CA, USA fUniversit´eCˆote d’Azur, Observatoire de la Cˆote d’Azur, CNRS, Laboratoire Lagrange, Boulevard de l’Observatoire, Nice, France Abstract We present an updated set of near-Earth asteroids with a Yarkovsky-related semi- major axis drift detected from the orbital fit to the astrometry. We find 87 reliable detections after filtering for the signal-to-noise ratio of the Yarkovsky drift esti- mate and making sure the estimate is compatible with the physical properties of the analyzed object. Furthermore, we find a list of 24 marginally significant detec- tions, for which future astrometry could result in a Yarkovsky detection. A further outcome of the filtering procedure is a list of detections that we consider spurious because unrealistic or not explicable with the Yarkovsky effect. Among the smallest asteroids of our sample, we determined four detections of solar radiation pressure, in addition to the Yarkovsky effect. As the data volume increases in the near fu- ture, our goal is to develop methods to generate very long lists of asteroids with reliably detected Yarkovsky effect, with limited amounts of case by case specific adjustments. -
Photometric Survey of 67 Near-Earth Objects S
A&A 615, A127 (2018) Astronomy https://doi.org/10.1051/0004-6361/201732154 & c ESO 2018 Astrophysics Photometric survey of 67 near-Earth objects S. Ieva1, E. Dotto1, E. Mazzotta Epifani1, D. Perna1,2, A. Rossi3, M. A. Barucci2, A. Di Paola1, R. Speziali1, M. Micheli1,4, E. Perozzi5, M. Lazzarin6, and I. Bertini6 1 INAF – Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Rome, Italy e-mail: [email protected] 2 LESIA – Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195 Meudon, France 3 IFAC – CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy 4 ESA SSA-NEO Coordination Centre„ Largo Galileo Galilei 1, 00044 Frascati (RM), Italy 5 Agenzia Spaziale Italiana, Via del Politecnico 1, 00100 Rome, Italy 6 Department of Physics and Astronomy “Galileo Galilei”, University of Padova, Vicolo dell’Osservatorio 3, 35122 Padova, Italy Received 23 October 2017 / Accepted 29 March 2018 ABSTRACT Context. The near-Earth object (NEO) population is a window into the original conditions of the protosolar nebula, and has the potential to provide a key pathway for the delivery of water and organics to the early Earth. In addition to delivering the crucial ingredients for life, NEOs can pose a serious hazard to humanity since they can impact the Earth. To properly quantify the impact risk, physical properties of the NEO population need to be studied. Unfortunately, NEOs have a great variation in terms of mitigation- relevant quantities (size, albedo, composition, etc.) and less than 15% of them have been characterized to date. -
AAS/DPS Poster (PDF)
Spacewatch Observations of Asteroids and Comets with Emphasis on Discoveries by WISE AAS/DPS Poster 13.22 Thurs. 2010 Oct 7: 15:30-18:00 Robert S. McMillan1, T. H. Bressi1, J. A. Larsen2, C. K. Maleszewski1,J. L. Montani1, and J. V. Scotti1 URL: http://spacewatch.lpl.arizona.edu 1University of Arizona; 2U.S. Naval Academy Abstract • Targeted recoveries of objects discovered by WISE as well as those on impact risk pages, NEO Confirmation Page, PHAs, comets, etc. • ~1900 tracklets of NEOs from Spacewatch each year. • Recoveries of WISE discoveries preserve objects w/ long Psyn from loss. • Photometry to determine albedo @ wavelength of peak of incident solar flux. • Specialize in fainter objects to V=23. • Examination for cometary features of objects w/ comet-like orbits & objects that WISE IR imagery showed as comets. Why Targeted Followup is Needed • Discovery arcs too short to define orbits. • Objects can escape redetection by surveys: – Surveys busy covering other sky (revisits too infrequent). – Objects tend to get fainter after discovery. • Followup observations need to outnumber discoveries 10-100. • Sky density of detectable NEOs too sparse to rely on incidental redetections alone. Why Followup is Needed (cont’d) • 40% of PHAs observed on only 1 opposition. • 18% of PHAs’ arcs <30d; 7 PHAs obs. < 3d. • 20% of potential close approaches will be by objects observed on only 1 opposition. • 1/3rd of H≤22 VI’s on JPL risk page are lost and half of those were discovered within last 3 years. How “lost” can they get? • (719) Albert discovered visually in 1911. • “Big” Amor asteroid, diameter ~2 km. -
Neodys (And Astdys and Priority List) Data Provision
NEODyS (and AstDyS and Priority List) Data Provision Fabrizio Bernardi CEO of SpaceDyS What is NEODyS • NEODyS is a web based service and stands for Near Earth Objects Dynamic Site: h@p://newton.dm.unipi.it/neodys • NEODyS provides informaon on the IMPACT PROBABILITY of Near Earth Objects (NEOs), typically for an horizon of 100 years • The most important output is the Risk Page: h@p://newton.dm.unipi.it/neodys2/index.php?pc=4.0 where a list of NEOs (459 on Nov 17th) with some chances of hing the Earth within the next century is posted for the public • Only JPL@NASA provides a similar service with SENTRY • NEODyS team has a technological leadership in Europe (and world) NEODyS background • NEODyS was born in 1999 at the Dep. of Mathemacs of the University of Pisa (Italy), within the CelesDal Mechanics Group (CMG) lead by Prof. Andrea Milani • The main moDvaon was the absence of a rigorous and systemac method for compuDng on a daily basis the probability that an asteroid is hing the Earth • The 1997XF11 case was a PR disaster, just for the lack of a well established system to perform such computaons NEODyS daily acDviDes • Since 1999 NEODyS is processing astrometric data of Near Earth Objects (NEOs) provided by the Minor Planet Center, the official enDty supported by the Internaonal Astronomical Union (IAU) that manages all the asteroids observaons and the official catalog of asteroids • The data are sent to NEODyS either by email or via web, through the Minor Planet Electronic Circulars (MPECs) • MPECs: – DOU à Daily Orbit Update: new observaons -
Near-Earth Objects
Near-Earth Objects 12/06/96 shows an elongated object about seen here in a NEAR spacecraft image 4.5 kilometers in extent. Veverka et al. (2000), Science, 289, Ostro et al. (1999), Icarus, 137: pp. 122-139. pp. 2088-2097. THE NEAR EARTH OBJECT POPULATION Near-Earth objects are an important area of study because they are relatively primitive bodies left over from the early solar system formation process, they can be utilized as raw materials for building future structures and habitats within the inner solar system, and their rare, but potentially catastrophic, collisions with Earth make them potential hazards. A comprehensive search for near-Earth objects (NEOs) not only ensures that there will be no surprises from Earth threatening objects but there will be new discoveries. During future close Earth approaches, these objects can be studied via ground-based programs including radar "imaging" characterizations and Earth orbital satellite observations (e.g., Hubble Space Telescope). In addition, these NE0 discoveries will provide future mission targets that are among the most accessible in terms of spacecraft energy requirements. Indeed, many near-Earth asteroids present easier rendezvous and landing opportunities than Earth's own Moon. While the vast majority of the rocky asteroids reside between the orbits of Mars and Jupiter and almost all the icy comets are resident in the so-called Kuiper belt and Oort cloud in the outer solar system, a significant number of these bodies reside in the Earth's neighborhood. Near-Earth asteroids and near-Earth comets make up the population of so-called near-Earth objects (NEOs). -
4 IAA Plane Etary Defen Nse C Onfer Rencee
4th IAA Planetary Defense Conference Assessing Impact Risk & Managing Response 13‐17 April 2015 Frascati, Italy PROGRAM 2015 IAA Planetary Defense Conference: PROGRAM Assessing Impact Risk & Managing Response PDC 2015 DAY April 13, 2015 1 0800 REGISTRATION 0900 WELCOMING REMARKS 0915 IAA‐PDC‐15‐00‐01 KEYNOTE: 15.02.2013 Chelyabinsk. Are we ready for O. Atkov a recurrence? 0945 BREAK SESSION 1: INTERNATIONAL PROGRAMS & ACTIVITIES Session Chairs: Detlef Koschny, Lindley Johnson 1000 IAA‐PDC‐15‐01‐01 The Near‐Earth Object Segment Of ESA’s SSA G. Drolshagen Programme 1020 IAA‐PDC‐15‐01‐02 Astronomical Aspects Of Building A System For B. Shustov Detecting And Monitoring Hazardous Space Objects 1040 IAA‐PDC‐15‐01‐03 The Achievements Of The NEOShield Project And The A. Harris (DLR) Promise Of NEOShield‐2 1100 IAA‐PDC‐15‐01‐04 Recent Enhancements To The NEO Observations L. Johnson Program: Implications For Planetary Defense 1120 IAA‐PDC‐15‐01‐05 Asia‐Pacific Asteroid Observation Network M. Yoshikawa 1140 INJECT 1: HYPOTHETICAL THREAT 1200 LUNCH SESSION 2: DISCOVERY, TRACKING, CHARACTERIZATION Session Chairs: Alan Harris (US), Alan Harris (DLR), Line Drube 1315 IAA‐PDC‐15‐02‐01 PAN‐STARRS Search For Near Earth Objects R. Wainscoat 1330 IAA‐PDC‐15‐02‐02 Design Characteristics Of An Optimized Ground S. Larson Based NEO Survey Telescope 1345 IAA‐PDC‐15‐02‐03 ATLAS – Warning For Impending Impact J. Tonry 1400 IAA‐PDC‐15‐02‐04 Sentinel Mission For Planetary Defense H. Reitsema 1415 IAA‐PDC‐15‐02‐05 Building On The NEOWISE Legacy With NEOCAM, The A. -
Project Pan-STARRS and the Outer Solar System
Project Pan-STARRS and the Outer Solar System David Jewitt Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822 ABSTRACT Pan-STARRS, a funded project to repeatedly survey the entire visible sky to faint limiting magnitudes (mR ∼ 24), will have a substantial impact on the study of the Kuiper Belt and outer solar system. We briefly review the Pan- STARRS design philosophy and sketch some of the planetary science areas in which we expect this facility to make its mark. Pan-STARRS will find ∼20,000 Kuiper Belt Objects within the first year of operation and will obtain accurate astrometry for all of them on a weekly or faster cycle. We expect that it will revolutionise our knowledge of the contents and dynamical structure of the outer solar system. Subject headings: Surveys, Kuiper Belt, comets 1. Introduction to Pan-STARRS Project Pan-STARRS (short for Panoramic Survey Telescope and Rapid Response Sys- tem) is a collaboration between the University of Hawaii's Institute for Astronomy, the MIT Lincoln Laboratory, the Maui High Performance Computer Center, and Science Ap- plications International Corporation. The Principal Investigator for the project, for which funding started in the fall of 2002, is Nick Kaiser of the Institute for Astronomy. Operations should begin by 2007. The science objectives of Pan-STARRS span the full range from planetary to cosmolog- ical. The instrument will conduct a survey of the solar system that is staggering in power compared to anything yet attempted. A useful measure of the raw survey power, SP , of a telescope is given by AΩ SP = (1) θ2 where A [m2] is the collecting area of the telescope primary, Ω [deg2] is the solid angle that is imaged and θ [arcsec] is the full-width at half maximum (FWHM) of the images { 2 { produced by the telescope.