1. New Worlds and Old © 2010 John Sheff Consulting Services

2. John Sheff Solar System Ambassador Program, Jet Propulsion Laboratory jsheff@cfa.harvard.edu http://www2.jpl.nasa.gov/ambassador/ http://ww.jsheff.com http://www.bostonastronomy.net Solar System Ambassador Program

3. Solar System Discoveries At first, all we knew about the planets was that they were "wanderers" against the background stars. Four hundred years ago, Galileo first turned the telescope to the sky, and the planets became "worlds." A half century ago, the first unmanned space probes started their explorations and the planets became "landscapes." What have we learned since about the planets of our Solar System and others? Is our Solar System unique? Are we close to finding another Earth? And -- most importantly of all -- what ever happened to Pluto? © 2010 John Sheff Consulting Services

4. Typical Ancient Astronomy  7 Planets (including the Sun and Moon, but not Earth):  Mercury  Venus  Mars  Jupiter  Saturn © 2010 John Sheff Consulting Services

5. Greek Astronomy

6. Nicolaus Copernicus (1473 – 1543)

7. Giordano Bruno (1548 – 1600) © 2010 John Sheff Consulting Services

8. Tycho Brahe (1546 – 1601)

9. Galileo Galilei (1564 – 1642)

10. Galileo’s Discoveries Lunar featuresStars in Milky Way

11. Galileo’s Discoveries Moons of JupiterPhases of Venus

12. Johannes Kepler (1571 – 1630)

13. Isaac Newton (1643 – 1727)

14. William Herschel (1738 – 1822)

15. Discovery of Uranus - 1781 © 2010 John Sheff Consulting Services

16. Uranus

17. Titius-Bode Law © 2010 John Sheff Consulting Services 1040.40.39Mercury 2370.70.72Venus 36101.01.00Earth 412161.61.52Mars 524282.82.77? 648525.25.20Jupiter 79610010.09.54Saturn 819219619.619.2Uranus 938438838.830.6? 107687727.7239.44?

18. Ceres © 2010 John Sheff Consulting Services

19. Pallas, Juno, Vesta PallasVesta © 2010 John Sheff Consulting Services

20. Vermin of the Skies © 2010 John Sheff Consulting Services

21. Irregularities of Motion - Uranus © 2010 John Sheff Consulting Services

22. Discovery of Neptune - 1846 Urbain Jean-Joseph Le Verrier John Couch Adams © 2010 John Sheff Consulting Services

23. Neptune

24. Irregularities of Motion - Mercury © 2010 John Sheff Consulting Services

25. Irregularities of Motion - Neptune © 2010 John Sheff Consulting Services

26. Lowell Observatory © 2010 John Sheff Consulting Services

27. Pluto – found at last! © 2010 John Sheff Consulting Services

28. 1992 QB1 © 2010 John Sheff Consulting Services

29. Eris (2003 UB₃₁₃) © 2010 John Sheff Consulting Services

30. The IAU Meeting: Prague 2006 © 2010 John Sheff Consulting Services

31. An Inventory of the Solar System  8 (or 9, 0r 13, or ?) Planets  169+ Moons  2 “Asteroid” Belts, with 100,000+ bodies ea  10 12 Comets  1 G2 Star  Interplanetary Medium © 2010 John Sheff Consulting Services

32. The Inner Solar System © 2010 John Sheff Consulting Services

33. The Asteroid Belt © 2010 John Sheff Consulting Services

34. The Outer Solar System © 2010 John Sheff Consulting Services

35. The Kuiper Belt © 2010 John Sheff Consulting Services

36. The New Solar System

37. Dwarf Planets and Some Contenders

38. Solar System Roadmap Flagship Missions (> 650 M$) Cassini Galileo New Frontiers (425 M$ - 650 M$) New Horizons Juno Discovery (< 425 M$) NEAR Messenger Dawn © 2010 John Sheff Consulting Services

39. Coming Up:  Venus Climate Orbiter/PLANET-C launch (5/2010)  Hayabusa return to Earth ? (6/2010)  Rosetta asteroid Lutetia flyby (7/10/2010)  Deep Impact Comet 103P/ Hartley 2 flyby (10/11/2010)  Venus Climate Orbiter/PLANET-C arrival (12/2010)  Stardust Comet Tempel 1 flyby (2/14/2011)  MESSENGER Mercury orbit (3/18/2011 – 3/18/2012)  Dawn Vesta orbiter (7/2011 – 7/2012)  Juno launch (8/5/2011)  MSL launch (10/2011)  Phobos Grunt launch (10/2011)  BepiColombo launch (8/2013)  Maven launch (11/18/2013 – 12/7/2013)  Maven Mars orbit (9/16/2014)  Dawn Ceres orbiter (2/2015 – 7/2015)  New Horizons Pluto flyby (7/2015)  ExoMars launch (4/2018 )  Juno Jupiter polar orbit (8/2016 – 10/2018)  BepiColombo Mercury orbit (8/2019 – 8/2020)

40. Mercury  Why is Mercury so dense?  What is the geologic history of Mercury?  What is the nature of Mercury’s magnetic field?  What is the structure of Mercury’s core?  What are the unusual materials at Mercury’s poles?  What volatiles are important at Mercury? © 2010 John Sheff Consulting Services

41. Mercury Exploration  Mariner 10 (1973-74)  MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) (2004 – 2012)  Bepi-Columbo (2014- 2020) © 2010 John Sheff Consulting Services

42. Venus © 2010 John Sheff Consulting Services

43. Venus Missions  Mariner 2 (1962)  Mariner 5 (1967)  Venera 4-16 (1967 – 1983)  Pioneer Venus (1978)  Vega (1984 – 1986)  Magellan (1989 – 1994)  Venus Express (2005 -  Planet C © 2010 John Sheff Consulting Services

44. Venus below the clouds Venera 13Venera 14 © 2010 John Sheff Consulting Services

45. Lunar Exploration - LRO © 2010 John Sheff Consulting Services

46. Lunar Science South Pole / Aitken Basin Sample Return Potential mission goals:  – Test cataclysm idea by dating SPA and superimposed basins  – Determine compositions of impacting bodies  – Decipher composition of mid- to lower crust (maybe mantle)  – Unravel basaltic history Complicated set of goals Complicated geologic setting © 2010 John Sheff Consulting Services

47. Mars  Strategy: From “Follow the Water” to “Explore Habitable Environments”  Determine if Life Ever Arose on Mars  Characterize the Climate of Mars  Characterize the Geology of Mars  Prepare for Human Exploration of Mars © 2010 John Sheff Consulting Services

48. Mars – Mariner 9 (1971)

49. Mars – Viking 1 & 2  Viking 1 & 2 (1975-80)  Viking 1: Chryse Planitia  Viking 2: Utopia © 2010 John Sheff Consulting Services

50. Mars Exploration Rovers  Spirit & Opportunity  6+ Years on Mars  Spirit: 4:80 miles  Opportunity: 11.94 miles © 2010 John Sheff Consulting Services

51. Mars Science Lab – “Curiosity” © 2010 John Sheff Consulting Services

52. Mars Sample Return – 2020 ? © 2010 John Sheff Consulting Services

53. Dawn - 2007 © 2010 John Sheff Consulting Services

54. Dawn Targets © 2010 John Sheff Consulting Services

55. Juno - 2011 Origins Determine the ratio of oxygen to hydrogen, giving an idea of the abundance of water on Jupiter. Obtain a better estimate of Jupiter's core mass, which will help distinguish among prevailing theories linking the gas giant's formation to the solar system. Interior Precisely map Jupiter's gravitational and magnetic fields to assess the distribution of mass in Jupiter's interior, including properties of the planet's structure and dynamics. Atmosphere Map the variation in atmospheric composition, temperature structure, cloud opacity and dynamics to depths far greater than 100 bars at all latitudes (In 1995, the Galileo probe reached only ~ 22 bars at a single location). Magnetosphere Characterize and explore the three dimensional structure of Jupiter's polar magnetosphere and its auroras. © 2010 John Sheff Consulting Services

56. Europa Explorer © 2010 John Sheff Consulting Services

57. Europa Explorer © 2010 John Sheff Consulting Services

58. Europa Astrobiology Lander © 2010 John Sheff Consulting Services

59. “Far” Future (2040 – 2050) ? © 2010 John Sheff Consulting Services  Europa Submersible

60. Saturn System © 2010 John Sheff Consulting Services

61. Iapetus Flyby Sept. 10, 2007 © 2010 John Sheff Consulting Services

62. Enceladus Flyby, Mar 12 2008 © 2010 John Sheff Consulting Services

63. Cassini-Huygens at Titan © 2010 John Sheff Consulting Services

64. Beyond the XM © 2010 John Sheff Consulting Services

65. Cassini XXM “Solstice” Mission © 2010 John Sheff Consulting Services

66. Cassini Mission Overview © 2010 John Sheff Consulting Services

67. Cassini EOM Option © 2010 John Sheff Consulting Services

68. Titan Explorer © 2010 John Sheff Consulting Services

69. Titan Explorer © 2010 John Sheff Consulting Services

70. Titan Lake Submersible © 2010 John Sheff Consulting Services

71. New Horizons  Launch: 2006  Jupiter Flyby Gravity Assist: 2007  Pluto / Charon Encounter: 2015  KBO Encounters: 2016- 2020 © 2010 John Sheff Consulting Services

72.  387 Detected as of November 2009  281 single planets around single normal stars  98 multiple-system planets around single normal stars  1 around red dwarf / white dwarf binary  1 around subdwarf B star / red dwarf binary  1 around pulsar / white dwarf binary  3 orbit single pulsars  1 orbits single subdwarf B star  1 orbits single brown dwarf Exoplanets

73. Pulsar Planets  Two planets discovered in 1992 around the millisecond pulsar PSR 1257+12.  These were the first two extrasolar planets discovered, and the first multi-planet extrasolar planetary system discovered, and the first pulsar planets discovered.  (b) had period of 66 days and mass of 4.3 Earths.  (c) had period of 98 days and mass of 3.9 Earths.  Two additional planets of lower mass were later discovered by the same technique

74. 51 Pegasi  First exoplanet around a main-sequence star (1995)  50 light-years away  Mass: > 1 Jupiter  Period: 4 days  “ Hot Jupiter”: surface temperature 1000 ° C (1800 ° F)

75. HD 222582 b  The planet orbiting this G3 star has one of the most eccentric planet orbits known to date. The 572- day orbit takes it from 0.39 AU to 2.31 AU from its star. It is located in the constellation Aquarius, 137 light-years distant. The water on this world's satellite, if one exists, goes through seasonal periods of melting and refreezing.

76. HD 177830 b  HD177830 b is a 1.52 Jupiter mass planet orbiting the K0 star HD177830, located 192 light-years away in the constellation Vulpecula. This planet is likely to be within its habitable zone. A moon found here could have liquid water and look similar to our own home world.

77. Upsilon Andromedae  The first planetary system ever found around a normal star consists of three planets in orbit around Upsilon Andromedae.  The innermost (and first known) of the three planets, Upsilon Andromedae b, contains at least three-quarters of the mass of Jupiter and orbits only 0.06 AU from the star. It traverses a circular orbit every 4.61 days.  The middle planet contains at least twice the mass of Jupiter and it takes 242 days to orbit the star once. It resides approximately 0.83 AU from the star, similar to the orbital distance of Venus.  The outermost planet has a mass of at least four Jupiters and completes one orbit every 3.5 to 4 years, placing it 2.5 AU from the star.

78. 55 Cancri  Five confirmed planets (most in any system)  The innermost planet (e): 2.8 day orbit, discovered in 2004. Mass: 11 Earth masses.  The next planet (a), discovered in 1996; 14.7-day orbit. Mass:.824 Jupiters.  Planet ( c ), with an orbit of 44.3 days. Mass: 56 Earth masses.  The fourth world (f) is the newest discovery, having 45 Earth masses and an orbit of 260 days. It is near the star’s “habitable zone”!  The farthest world out (d)has an orbit comparable to Jupiter's. Period: 14.6 years.

79. Gliese 581  At least four planets are believed to be orbiting Gliese 581.  A fourth planet, Gliese 581 e, was discovered in 2009. This planet, at an estimated minimum mass of 1.9 Earths, is currently the lowest mass exoplanet identified around a normal star. It takes 3.15 days to orbit Gliese 581- but it’s too hot!  Gliese 581 b is at least 16 times as massive as Earth (similar to Neptune's mass) and completes a full orbit of Gliese 581 in only 5.4 days.  Gliese 581 c is probably a rocky planet with a radius 1.5 times that of Earth and a mass of roughly five times Earth— or one third that of Neptune. Gliese 581 c orbits just inside of the habitable zone of its parent star. It is notable as it is the planet with lowest minimum mass yet discovered in the habitable zone of another star, making it the most earthlike exoplanet found to date. [ The mean blackbody surface temperature has been estimated to lie between -3 °C (for a Venus-like albedo) and 40 °C (for an Earth-like albedo), however, the temperatures could be much higher (about 500 degrees Celsius) due to a runaway greenhouse effect akin to that of Venus. Gliese 581 c completes a full orbit in just under 13 days.  Observations of the star also revealed a third planet, Gliese 581 d, with a mass of roughly 7 Earths, or half a Uranus, and an orbit of 66.8 Earth days. It orbits just inside of the habitable zone of its star, which makes it a potential candidate for being able to support life. “Water world?”

80. Kepler Mission  Launched : March 6, 2009  First Light: April 16, 2009  Checkout Ended: May 13, 2009  Data Collection: 3.5 years  Will monitor field of 223,000 stars  Should find:  ~ 30 outer-orbit giant planets  ~ 135 inner-orbit giant planets  ~ 640 Super-Earths  ~ 50 Earth-mass planets

81. A New Earth?  Within the next 5 years, we will probably find another Earth-like planet – an Earth- sized world in a stable orbit in a HZ of a Sun-like star

82. John Sheff Solar System Ambassador Program, Jet Propulsion Laboratory jsheff@cfa.harvard.edu http://www2.jpl.nasa.gov/ambassador/ Background: John Sheff has explored some remote parts of our planet on adventure travel journeys and mountaineering expeditions. His lifelong background as an amateur astronomer and space buff has him just as excited about the exploration of other planets. He enjoys participating in star parties, particularly inner-city ones, organized by his local club – the Amateur Telescope Makers of Boston (ATMoB). He also loves to share views of the sky through the observatory telescope he operates during Public Nights at the Harvard- Smithsonian Center for Astrophysics in Cambridge. In his day job he’s had a career as a freelance Network Admin and IT Manager, and now does consulting in web development and science education. When on Earth, he lives in Cambridge, MA. Portions of this PowerPoint Slide Show - as well as a free installable PowerPoint Viewer - are available for download on John Sheff’s website: http://www.jsheff.com Solar System Ambassador Program © 2010 John Sheff Consulting Services