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CNY Observers & Observing Damian G. Allis, Ph.D A Big Year For Dwarf Planets: Highlights Of The NASA Missions To Ceres & Pluto (and many, many, many more) Damian G. Allis, Ph.D. NASA Solar System Ambassador Director, CNYO CNY Observers & Observing Promoting Amateur Astronomy And Space Science In Central New 1York Ceres & Pluto (and many, many, many more) Damian G. Allis, Ph.D. NASA Solar System Ambassador Dept. of Chemistry, Syracuse University CNY Observers & Observing Promoting Amateur Astronomy And Space Science In Central New 2York The Next Hour Or So • Solar System Refresher • Ceres – The Planet That Couldn’t • Dawn @ Ceres • Pluto – The Planet That Ain’t • New Horizons @ Pluto • “The Lollipop Guild” • Final Thoughts 3 Sloan Digital Sky Survey PNSA “A RELATION BETWEEN DISTANCE AND RADIAL VELOCITY AMONG EXTRA-GALACTIC NEBULAE” PNAS, Vol. 15, No. 3, 1929 Sloan Digital Sky Survey 9 map.gsfc.nasa.gov/m_ig/030644/030644.html en.wikipedia.org/wiki/Observable_universe en.wikipedia.org/wiki/Observable_universe M31 (and M32 and M110) en.wikipedia.org/wiki/Observable_universe Astrophysical Journal, Vol. 801, pg. 105, 2015 en.wikipedia.org/wiki/Observable_universe http://www.universetoday.com/32522/oort-cloud/ https://en.wikipedia.org/wiki/Oort_cloud 18 en.wikipedia.org/wiki/Observable_universe 20 http://www.paulschow.com/2013/03/us-sized-scale-model-solar-system.html 21 Ceres (and the Asteroid Belt) 22 www.nature.com/nature/journal/v505/n7485/full/nature12908.html 23 24 www.nasa.gov/mission_pages/spitzer/news/spitzervega20130108.html • “Nearly Empty” • Total Composition = 4% The Moon • 1 km-Sized Objects = 8 Earth-Moon Separations (on average) • Carbonaceous, Silicate, and Metallic Compositions • Key Players – Ceres, Vesta, Pallas, Hygiea, Eros, Ida… 25 26 http://www.universetoday.com/32856/asteroid-belt/ Ceres Background: Fr. Giuseppe Piazzi, 1 January 1801 Palermo, Italy Thought is was a planet, but then… “Binocular Object” Orbital Period: 4.6 yr Synodic Period: 1.3 yr 27 https://en.wikipedia.org/wiki/Ceres_%28dwarf_planet%29 28 https://en.wikipedia.org/wiki/Ceres_%28dwarf_planet%29 29 30 https://www.youtube.com/watch?v=wVL0ZvKKoUE 31 Dawn Mission 32 33 34 Mission Details: Launch – 27 Sept 2007 Arrival @ Vesta – 16 July 2011 Arrival @ Ceres – 6 March 2015 End-Of-Line – Permanent Orbit 35 www.rocketstem.org/2015/03/01/exploring-the-dawn-of-the-solar-system/ 36 What We Know 37 http://www.space.com/22891-ceres-dwarf-planet.html 38 39 40 Pluto 41 Pluto Background: Clyde Tombaugh, 18 February 1930 Lowell Observatory, Flagstaff AZ “Big Scope Object” ry Orbital Period: 248 yr Synodic Period: 367 dy 42 Odd Orbit 43 What Makes A Planet? Orbit the Sun Spherical Shape (from gravity) “Cleared the neighborhood” of its orbit http://www.universetoday.com/13573/why-pluto-is-no-longer-a-planet/ 44 Not all That (other objects) 45 After Demotion (Hubble) 46 www.nasa.gov/images/content/571868main_i1123ay.jpg 47 www.wired.com/2015/07/pluto-new-horizons/ 48 49 What We Know 50 www.youtube.com/watch?v=mfQq2b4VT84 51 Geology 52 Announced 20 Nov, pluto.jhuapl.edu/ Clyde On The Ride 53 Many, Many, Many More… 54 134340 Pluto, a dwarf planet (225088) 2007 OR10 the largest object in the Solar System without a name (15760) 1992 QB1, the prototype cubewano, the first Kuiper belt object discovered after Pluto 1998 WW31, the first binary Kuiper belt object discovered after Pluto 79360 Sila–Nunam, another binary Kuiper belt planet with similar both parts (47171) 1999 TC36, almost triple Kuiper belt (15874) 1996 TL66, the first object to be identified as a scattered disc object (48639) 1995 TL8 has a very large satellite (385185) 1993 RO, the next plutino discovered after Pluto 20000 Varuna and 50000 Quaoar, large cubewanos 90482 Orcus and 28978 Ixion, large plutinos 90377 Sedna, a distant object, proposed for a new category named extended scattered disc (E-SDO), detached objectsMostest, distant Distant detached Yet (Until objects the next (DDO) one) or scattered-extended in the formal classification by DES 120347 Salacia, large cubewano with a large moon 136108 Haumea, a dwarf planet, the fourth-largest known trans-Neptunian object. Notable for its two known satellites and unusually short rotation period (3.9 h). 136199 Eris, a dwarf planet, a scattered disc object, and currently the most massive known trans-Neptunian object. It has one known satellite, Dysnomia. 136472 Makemake, a dwarf planet, a cubewano, and the third-largest known trans- Neptunian object 2004 XR190, a scattered disc object following a highly inclined but nearly circular orbit (87269) 2000 OO67 and (148209) 2000 CR105, remarkable for their eccentric 2008 KV42, the first retrograde TNO, having an orbital inclination of i = 104° 2012 VP113, a likely dwarf planet with the greatest perihelion of any known TNO 55 V774104, at ~103scitechdaily.com/distant-dwarf-planet-discovered-beyond-known-edge-solar-system/ AU the currently most distant observable TNO, based on discoveries up to November 2015 Final Thoughts • Earth’s Rotation At 43o North – 1500 km/hour • Earth’s Motion Around Sun – 107,000 km/hour • Sun’s Motion In Milky Way – 792,000 km/hour • Milky Way In “The Universe” – 1,987,200 km/hour • Sitting Here – 2,887,700 km (around the Earth 72 times) • 56 www.cnyo.org [email protected] (facebook, twitter, google, youtube) Ceres & Pluto (and many, many, many more) Damian G. Allis, Ph.D. NASA Solar System Ambassador Dept. of Chemistry, Syracuse University CNY Observers & Observing Promoting Amateur Astronomy And Space Science In Central New57 York.
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  • A Deeper Look at the Colors of the Saturnian Irregular Satellites Arxiv
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