Observing 27 Euterpe the Asteroid

Total Page:16

File Type:pdf, Size:1020Kb

Observing 27 Euterpe the Asteroid Observing 27 Euterpe the Asteroid College Park Scholars Academic Showcase May 6, 2016 Shervin Razazi, [email protected], SDU Research Question How can we determine the rotation rate of an asteroid? Intro Why Research This? My Project group is called Explore the Universe Astronomers use the data in order to find out more and we are a group of mostly SDU scholars specific properties of asteroids. For example, an students who conduct research on various asteroid with a rotation period of under 2.2 hours is observable astronomical phenomena. My specific generally considered too small to be a self sustaining project was to observe an asteroid and then structure, which means that while in the asteroid belt determine the rotation rate of that asteroid. The they are too small to be held together by themselves asteroid I ended up observing is named 27 This suggests that these smaller bodies were once Euterpe. parts of larger asteroids. The data from all the thousands of asteroids being observe allow us to learn more and more about the solar system and its origins. Photo C.R. Shervin Razazi Limitations How This Affected Me Photometry • Weather Doing this project was not my first choice. As a Chemical • Analyze with Astro Image J • Clouds Engineer astronomy is not something I have ever studied or • Calibrate raw images • Humidity thought I would ever be doing. Even though it is not relevant • Align calibrated photos • Wind to my major it did teach me how hard it is to collect accurate • Generate light curve • Position of Asteroid scientific data. After spending time on this project I have • Gives a lot of information about asteroid • Past the horizon learned how to observe space phenomena. This project also • The time difference between peaks is the • Position of nearby stars taught me a lot about responsibility and how to manage my estimated rotation period. • Time time in order to meet project deadlines while balancing • Different asteroid generate different • Asteroid not observable at some times schoolwork at the same time. shaped light curve due to their different of the night shapes. • Hard to go observe at 3 am Methodology Analysis First step whenever we have to start an The countless amount of hours that astronomers observation is to get the telescope in focus. After spend observing small bodies such as asteroids may that we have to sync the telescope onto a star near seem fruitless, considering that in most telescopes the our target. The next stop is to generate an size of the asteroid is a single pixel. Combined with the ephemeris which lists the coordinates of the inherent dependency on weather for getting quality asteroid on different days and times. From there data astronomy is a long and tedious process. But one we generate star chars which show our asteroid in that is very useful for physicists and scientists the night sky with stars around it. This is in order to worldwide. The data that astronomers get from their locate our asteroid in the images. We then set up a observations allows scientists to form predictions sequence in the software Maxim DL This sequence about how planets are formed, how the effect of light tells our telescope how many pictures to take, at from a nearby star influences the light another space what exposures, and which filters to use. body emits as well. Photo C.R. Stephens et al Acknowledgements to Elizabeth Warner, Mentor and the Director of the UMD observatory.
Recommended publications
  • Instrumental Methods for Professional and Amateur
    Instrumental Methods for Professional and Amateur Collaborations in Planetary Astronomy Olivier Mousis, Ricardo Hueso, Jean-Philippe Beaulieu, Sylvain Bouley, Benoît Carry, Francois Colas, Alain Klotz, Christophe Pellier, Jean-Marc Petit, Philippe Rousselot, et al. To cite this version: Olivier Mousis, Ricardo Hueso, Jean-Philippe Beaulieu, Sylvain Bouley, Benoît Carry, et al.. Instru- mental Methods for Professional and Amateur Collaborations in Planetary Astronomy. Experimental Astronomy, Springer Link, 2014, 38 (1-2), pp.91-191. 10.1007/s10686-014-9379-0. hal-00833466 HAL Id: hal-00833466 https://hal.archives-ouvertes.fr/hal-00833466 Submitted on 3 Jun 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Instrumental Methods for Professional and Amateur Collaborations in Planetary Astronomy O. Mousis, R. Hueso, J.-P. Beaulieu, S. Bouley, B. Carry, F. Colas, A. Klotz, C. Pellier, J.-M. Petit, P. Rousselot, M. Ali-Dib, W. Beisker, M. Birlan, C. Buil, A. Delsanti, E. Frappa, H. B. Hammel, A.-C. Levasseur-Regourd, G. S. Orton, A. Sanchez-Lavega,´ A. Santerne, P. Tanga, J. Vaubaillon, B. Zanda, D. Baratoux, T. Bohm,¨ V. Boudon, A. Bouquet, L. Buzzi, J.-L. Dauvergne, A.
    [Show full text]
  • Accurate Positions of Pluto and Asteroids Observed in Bucharest During the Year 1932
    ACCURATE POSITIONS OF PLUTO AND ASTEROIDS OBSERVED IN BUCHAREST DURING THE YEAR 1932 GHEORGHE BOCŞA, PETRE POPESCU, MIHAELA LICULESCU Astronomical Institute of the Romanian Academy Str. Cuţitul de Argint 5, 040557 Bucharest, Romania E-mail: [email protected] Abstract. The paper contains the observations of minor planets performed in Bucharest Astronomical Observatory in the year 1932 with the 380/6000 mm astrograph. Both Turner’s (constants) and Schlesinger’s (dependences) methods were used in the computation of the normal coordinates of the objects. Keywords: photographic astrometry – minor planets. 1. INTRODUCTION The article is a continuation of the complete investigation of Bucharest Wide-Field Plates Archive initiated in 2010; it contains the plates with asteroids observed in 1932. That year 185 plates were exposed and were stored in the archive, but were not reduced. After analysing them, 98 plates were detected to contain measurable minor planets. The first observed positions in this year were of planet Pluto. They were exposed on 1318cm plates, with 52 minutes exposure .The observations were performed by the famous Romanian astronomer Professor Gheorghe Demetrescu. The most difficult problem was the identification of the planet, the three plates obtained in 1932 having dozens of stars with up to 15 magnitudes. As all the observations were performed in the same month and the planet did not have a great proper motion, it was possible to superpose two plates and to identify Pluto. The values (O–C)α and (O–C)δ were calculated by M. Svechnikov from the Institute of Applied Astronomy in Sankt Petersburg on the basis of precise positions obtained in Bucharest, which we integrated in Pluto’s orbit.
    [Show full text]
  • An Asteroid Main Belt Tour and Survey N.E
    CASTAway: An asteroid main belt tour and survey N.E. Bowles, C. Snodgrass, A. Gibbings, J.P. Sanchez, J.A. Arnold, P. Eccleston, T. Andert, A. Probst, G. Naletto, A.C. Vandaele, et al. To cite this version: N.E. Bowles, C. Snodgrass, A. Gibbings, J.P. Sanchez, J.A. Arnold, et al.. CASTAway: An aster- oid main belt tour and survey. Advances in Space Research, Elsevier, 2018, 62 (8), pp.1998-2025. 10.1016/j.asr.2017.10.021. hal-01902144 HAL Id: hal-01902144 https://hal.archives-ouvertes.fr/hal-01902144 Submitted on 23 Oct 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. an author's https://oatao.univ-toulouse.fr/19380 http://dx.doi.org/10.1016/j.asr.2017.10.021 Bowles, N.E. , Snodgrass, C. , Gibbings, A.,...[et all.] CASTAway: An asteroid main belt tour and survey. (2018) Advances in Space Research, 62 (8). 1998-2025. ISSN 0273-1177 CASTAway: An asteroid main belt tour and survey N.E. Bowles a,⇑, C. Snodgrass b, A. Gibbings c, J.P. Sanchez d, J.A. Arnold a, P. Eccleston e, T.
    [Show full text]
  • ASTRONOMY and ASTROPHYSICS the Hipparcos Solar System Objects Catalogues?
    Astron. Astrophys. 334, 325–336 (1998) ASTRONOMY AND ASTROPHYSICS The Hipparcos solar system objects catalogues? D.Hestroffer1,2, B. Morando2??,E.Høg3, J. Kovalevsky4, L. Lindegren5, and F. Mignard4 1 Astrophysics Division, Space Science Department of ESA, ESTEC, Postbus 299, 2200 AG Noordwijk, The Netherlands 2 Bureau Des Longitudes, URA CNRS 707, 77 Avenue Denfert Rochereau, F-75014 Paris, France 3 Copenhagen University Observatory, Juliane Maries Vej 30, DK-2100 Copenhagen O., Denmark 4 Observatoire de la Coteˆ d’Azur, Departement´ CERGA, UMR CNRS 6527, Av. N. Copernic, F-06130 Grasse, France 5 Lund Observatory, Box 43, S-22100 Lund, Sweden Received 15 October 1997 / Accepted 28 January 1998 Abstract. Astrometric and photometric measurements of a Sun or major planets. Nonetheless, the theoretical precision esti- number of solar system objects were performed by the Hip- mated by Clemence (1948) has never been reached; hence such parcos satellite in both the Hipparcos main mission and the Ty- observations of minor planets enter for instance in the solution cho experiment. The results concern mainly asteroids but also derived by Fricke (1982) for the FK5 with a relatively modest the planetary satellites Europa, Ganymede, Callisto, Titan and weight. Hipparcos should dramatically improve the situation Iapetus, and the major planets Uranus and Neptune. The spe- (e.g. Hestroffer et al. 1995; Bec-Borsenberger et al. 1995), and cific aspects of the Tycho/Hipparcos observations and reduction yield a link between the dynamical system and the ICRS with process implemented for the solar system objects are presented. a precision of the same order of magnitude as the best result Special attention is paid to the error budget of the reduction obtained so far by other means (Folkner et al.
    [Show full text]
  • Solar System Objects in the ISOPHOT 170 Μm Serendipity Survey
    A&A 389, 665–679 (2002) Astronomy DOI: 10.1051/0004-6361:20020596 & c ESO 2002 Astrophysics Solar system objects in the ISOPHOT 170 µm serendipity survey? T. G. M¨uller1,2, S. Hotzel3, and M. Stickel3 1 Max-Planck-Institut f¨ur extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany 2 ISO Data Centre, Astrophysics Division, Space Science Department of ESA, Villafranca, PO Box 50727, 28080 Madrid, Spain (until Dec. 2001) 3 ISOPHOT Data Centre, Max-Planck-Institut f¨ur Astronomie, K¨onigstuhl 17, 69117 Heidelberg, Germany Received 14 January 2002 / Accepted 12 March 2002 Abstract. The ISOPHOT Serendipity Survey (ISOSS) covered approximately 15% of the sky at a wavelength of 170 µm while the ISO satellite was slewing from one target to the next. By chance, ISOSS slews went over many solar system objects (SSOs). We identified the comets, asteroids and planets in the slews through a fast and effective search procedure based on N-body ephemeris and flux estimates. The detections were analysed from a calibration and scientific point of view. Through the measurements of the well-known asteroids Ceres, Pallas, Juno and Vesta and the planets Uranus and Neptune it was possible to improve the photometric calibration of ISOSS and to extend it to higher flux regimes. We were also able to establish calibration schemes for the important slew end data. For the other asteroids we derived radiometric diameters and albedos through a recent thermophysical model. The scientific results are discussed in the context of our current knowledge of size, shape and albedos, derived from IRAS observations, occultation measurements and lightcurve inversion techniques.
    [Show full text]
  • A Radar Survey of Main-Belt Asteroids: Arecibo Observations of 55 Objects During 1999–2003
    Icarus 186 (2007) 126–151 www.elsevier.com/locate/icarus A radar survey of main-belt asteroids: Arecibo observations of 55 objects during 1999–2003 Christopher Magri a,∗, Michael C. Nolan b,StevenJ.Ostroc, Jon D. Giorgini d a University of Maine at Farmington, 173 High Street—Preble Hall, Farmington, ME 04938, USA b Arecibo Observatory, HC3 Box 53995, Arecibo, PR 00612, USA c 300-233, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA d 301-150, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA Received 3 June 2006; revised 10 August 2006 Available online 24 October 2006 Abstract We report Arecibo observations of 55 main-belt asteroids (MBAs) during 1999–2003. Most of our targets had not been detected previously with radar, so these observations more than double the number of radar-detected MBAs. Our bandwidth estimates constrain our targets’ pole directions in a manner that is geometrically distinct from optically derived constraints. We present detailed statistical analyses of the disk-integrated properties (radar albedo and circular polarization ratio) of the 84 MBAs observed with radar through March 2003; all of these observations are summarized in the online supplementary information. Certain conclusions reached in previous studies are strengthened: M asteroids have higher mean radar albedos and a wider range of albedos than do other MBAs, suggesting that both metal-rich and metal-poor M-class objects exist; and C- and S-class MBAs have indistinguishable radar albedo distributions, suggesting that most S-class objects are chondritic. Also in accord with earlier results, there is evidence that primitive asteroids from outside the C taxon (F, G, P, and D) are not as radar-bright as C and S objects, but a convincing statistical test must await larger sample sizes.
    [Show full text]
  • The Minor Planet Bulletin Is Open to Papers on All Aspects of 6500 Kodaira (F) 9 25.5 14.8 + 5 0 Minor Planet Study
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 32, NUMBER 3, A.D. 2005 JULY-SEPTEMBER 45. 120 LACHESIS – A VERY SLOW ROTATOR were light-time corrected. Aspect data are listed in Table I, which also shows the (small) percentage of the lightcurve observed each Colin Bembrick night, due to the long period. Period analysis was carried out Mt Tarana Observatory using the “AVE” software (Barbera, 2004). Initial results indicated PO Box 1537, Bathurst, NSW, Australia a period close to 1.95 days and many trial phase stacks further [email protected] refined this to 1.910 days. The composite light curve is shown in Figure 1, where the assumption has been made that the two Bill Allen maxima are of approximately equal brightness. The arbitrary zero Vintage Lane Observatory phase maximum is at JD 2453077.240. 83 Vintage Lane, RD3, Blenheim, New Zealand Due to the long period, even nine nights of observations over two (Received: 17 January Revised: 12 May) weeks (less than 8 rotations) have not enabled us to cover the full phase curve. The period of 45.84 hours is the best fit to the current Minor planet 120 Lachesis appears to belong to the data. Further refinement of the period will require (probably) a group of slow rotators, with a synodic period of 45.84 ± combined effort by multiple observers – preferably at several 0.07 hours. The amplitude of the lightcurve at this longitudes. Asteroids of this size commonly have rotation rates of opposition was just over 0.2 magnitudes.
    [Show full text]
  • On March 16 , 2019 Fifteen Years of the Faulkes Telescope Project
    On March 16th, 2019 fifteen years of the Faulkes Telescope Project Our participation in this great adventure Andre Debackere March 2019 We started observations with the Faulkes Telescopes in January 2010. We studied different types of astronomical objects as part of - scientific workshop called “ASAM” at College Le Monteil, Monistrol sur Loire, France - European Comenius project, 6 schools in 5 countries - educational activities, 3 teachers and 2 schools - personal research, hunting binaries, measurements and discoveries 1) Scientific workshop from January 2010 to June 2016 with a dozen college students (12-16 years old) a) Our first subject of study : Trans-Neptunians and dwarf planets, astrometry and animations Learn how to use the Faulkes Telescope interface and the tools as “target visibility” and “exposure time calculator”. To be able to recognize the target in the stellar field by using ALADIN, CDS, Strasbourg, France and ASTROMETRICA, Herbert Raab, Austria. Make animations showing the motion of the asteroid against the starry sky background (with SALSAJ, EUHOU or ASTROMETRICA). How to locate an object in the sky, celestial coordinates (right ascension and declination), their measurements with ASTOMETRICA. The 2m telescopes (FTN & FTS) are powerful instruments so we started by studying the trans- Neptunians, very distant asteroids some of which are candidates for the rank of dwarf planets as for example Varuna and Orcus. (20000) Varuna discovered in 2000 and (90482) Orcus discovered in 2004 are both trans- Neptunian object from
    [Show full text]
  • Asteroids As Radial Velocity and Resolving Power Standards for Medium and High Resolution Spectroscopy
    A&A 462, 795–799 (2007) Astronomy DOI: 10.1051/0004-6361:20053717 & c ESO 2007 Astrophysics Asteroids as radial velocity and resolving power standards for medium and high resolution spectroscopy T. Zwitter1, F. Mignard2, and F. Crifo3 1 University of Ljubljana, Faculty of Mathematics and Physics, Department of Physics, Jadranska 19, 1000 Ljubljana, Slovenia e-mail: [email protected] 2 Observatoire de la Côte d’Azur, Cassiopée, CNRS UMR 5202, BP 4229, 06304 Nice Cedex 4, France 3 Observatoire de Paris, GEPI, 5 place Jules Janssen, 92195 Meudon, France Received 29 June 2005 / Accepted 30 August 2006 ABSTRACT Echelle spectra of 10 bright asteroids are presented and compared against an observed twilight spectrum and a computed Solar spectrum. Spectra covering a 2130 Å spectral range centered on λ = 5785 Å are of high resolving power and high signal to noise ratio. We compare detailed properties of spectral lines and not albedo variations. It is shown that the normalized Solar and asteroid spectra are identical except for radial velocity (RV) shifts which can be predicted at accuracy level of 1 m s−1. So asteroids are proposed as new and extremely accurate radial velocity standards. Predicted and measured RVs of observed asteroids match within the limits of accuracy of the instrument. There are numerous absorption lines in the reflected Solar spectrum. This allows a direct mapping of the resolving power of a spectrograph between and along echelle spectral orders. Thus asteroid spectra can be used to test the wavelength calibration and resolving power of spectrographs on the ground as well as in space, including the Gaia mission of ESA.
    [Show full text]
  • Cumulative Index to Volumes 1-45
    The Minor Planet Bulletin Cumulative Index 1 Table of Contents Tedesco, E. F. “Determination of the Index to Volume 1 (1974) Absolute Magnitude and Phase Index to Volume 1 (1974) ..................... 1 Coefficient of Minor Planet 887 Alinda” Index to Volume 2 (1975) ..................... 1 Chapman, C. R. “The Impossibility of 25-27. Index to Volume 3 (1976) ..................... 1 Observing Asteroid Surfaces” 17. Index to Volume 4 (1977) ..................... 2 Tedesco, E. F. “On the Brightnesses of Index to Volume 5 (1978) ..................... 2 Dunham, D. W. (Letter regarding 1 Ceres Asteroids” 3-9. Index to Volume 6 (1979) ..................... 3 occultation) 35. Index to Volume 7 (1980) ..................... 3 Wallentine, D. and Porter, A. Index to Volume 8 (1981) ..................... 3 Hodgson, R. G. “Useful Work on Minor “Opportunities for Visual Photometry of Index to Volume 9 (1982) ..................... 4 Planets” 1-4. Selected Minor Planets, April - June Index to Volume 10 (1983) ................... 4 1975” 31-33. Index to Volume 11 (1984) ................... 4 Hodgson, R. G. “Implications of Recent Index to Volume 12 (1985) ................... 4 Diameter and Mass Determinations of Welch, D., Binzel, R., and Patterson, J. Comprehensive Index to Volumes 1-12 5 Ceres” 24-28. “The Rotation Period of 18 Melpomene” Index to Volume 13 (1986) ................... 5 20-21. Hodgson, R. G. “Minor Planet Work for Index to Volume 14 (1987) ................... 5 Smaller Observatories” 30-35. Index to Volume 15 (1988) ................... 6 Index to Volume 3 (1976) Index to Volume 16 (1989) ................... 6 Hodgson, R. G. “Observations of 887 Index to Volume 17 (1990) ................... 6 Alinda” 36-37. Chapman, C. R. “Close Approach Index to Volume 18 (1991) ..................
    [Show full text]
  • New and Updated Convex Shape Models of Asteroids Based on Optical Data from a Large Collaboration Network
    A&A 586, A108 (2016) Astronomy DOI: 10.1051/0004-6361/201527441 & c ESO 2016 Astrophysics New and updated convex shape models of asteroids based on optical data from a large collaboration network J. Hanuš1,2,J.Durechˇ 3, D. A. Oszkiewicz4,R.Behrend5,B.Carry2,M.Delbo2,O.Adam6, V. Afonina7, R. Anquetin8,45, P. Antonini9, L. Arnold6,M.Audejean10,P.Aurard6, M. Bachschmidt6, B. Baduel6,E.Barbotin11, P. Barroy8,45, P. Baudouin12,L.Berard6,N.Berger13, L. Bernasconi14, J-G. Bosch15,S.Bouley8,45, I. Bozhinova16, J. Brinsfield17,L.Brunetto18,G.Canaud8,45,J.Caron19,20, F. Carrier21, G. Casalnuovo22,S.Casulli23,M.Cerda24, L. Chalamet86, S. Charbonnel25, B. Chinaglia22,A.Cikota26,F.Colas8,45, J.-F. Coliac27, A. Collet6,J.Coloma28,29, M. Conjat2,E.Conseil30,R.Costa28,31,R.Crippa32, M. Cristofanelli33, Y. Damerdji87, A. Debackère86, A. Decock34, Q. Déhais36, T. Déléage35,S.Delmelle34, C. Demeautis37,M.Dró˙zd˙z38, G. Dubos8,45, T. Dulcamara6, M. Dumont34, R. Durkee39, R. Dymock40, A. Escalante del Valle85, N. Esseiva41, R. Esseiva41, M. Esteban24,42, T. Fauchez34, M. Fauerbach43,M.Fauvaud44,45,S.Fauvaud8,44,45,E.Forné28,46,†, C. Fournel86,D.Fradet8,45, J. Garlitz47, O. Gerteis6, C. Gillier48, M. Gillon34, R. Giraud34, J.-P. Godard8,45,R.Goncalves49, Hiroko Hamanowa50, Hiromi Hamanowa50,K.Hay16, S. Hellmich51,S.Heterier52,53, D. Higgins54,R.Hirsch4, G. Hodosan16,M.Hren26, A. Hygate16, N. Innocent6, H. Jacquinot55,S.Jawahar56, E. Jehin34, L. Jerosimic26,A.Klotz6,57,58,W.Koff59, P. Korlevic26, E. Kosturkiewicz4,38,88,P.Krafft6, Y. Krugly60, F. Kugel19,O.Labrevoir6, J.
    [Show full text]
  • The Minor Planet Bulletin
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 34, NUMBER 3, A.D. 2007 JULY-SEPTEMBER 53. CCD PHOTOMETRY OF ASTEROID 22 KALLIOPE Kwee, K.K. and von Woerden, H. (1956). Bull. Astron. Inst. Neth. 12, 327 Can Gungor Department of Astronomy, Ege University Trigo-Rodriguez, J.M. and Caso, A.S. (2003). “CCD Photometry 35100 Bornova Izmir TURKEY of asteroid 22 Kalliope and 125 Liberatrix” Minor Planet Bulletin [email protected] 30, 26-27. (Received: 13 March) CCD photometry of asteroid 22 Kalliope taken at Tubitak National Observatory during November 2006 is reported. A rotational period of 4.149 ± 0.0003 hours and amplitude of 0.386 mag at Johnson B filter, 0.342 mag at Johnson V are determined. The observation of 22 Kalliope was made at Tubitak National Observatory located at an elevation of 2500m. For this study, the 410mm f/10 Schmidt-Cassegrain telescope was used with a SBIG ST-8E CCD electronic imager. Data were collected on 2006 November 27. 305 images were obtained for each Johnson B and V filters. Exposure times were chosen as 30s for filter B and 15s for filter V. All images were calibrated using dark and bias frames Figure 1. Lightcurve of 22 Kalliope for Johnson B filter. X axis is and sky flats. JD-2454067.00. Ordinate is relative magnitude. During this observation, Kalliope was 99.26% illuminated and the phase angle was 9º.87 (Guide 8.0). Times of observation were light-time corrected.
    [Show full text]