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Dawn PowerPoint Presentation

Dawn

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Dawn

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  1. Waiting for their spaceships to come in… …with help from Hubble in the meanwhile Dawn New Horizons Pluto 2015 Ceres 2015 Vesta 2011

  2. Citation from IAU Minor Planet Circular 56612 on the naming of Asteroid “6815 Mutchler”

  3. Asteroids “ready for their close-up” Max Mutchler Head, Research & Instrument Analysis Branch Space Telescope Science Institute Public Lecture, 1 March 2011

  4. Asteroids “ready for their close-up” Max Mutchler Head, Research & Instrument Analysis Branch Space Telescope Science Institute Public Lecture, 1 March 2011

  5. “I’m ready for my close-up, Mr. DeVille” "I am big, it's the pictures that got small!" - Gloria Swanson

  6. “I’m ready for my close-up, Dawn” "I am small, it's the pictures that got big!" - Asteroid Vesta

  7. Asteroid history and mystery Ceres, Vesta, Pallas, discovered in early 1800s Called planets for 50 years, then re-classified: any déjà vu ? Key to understanding Solar System formation …and us Giveth: our oceans? Taketh away: Killed the dinosaurs? Still a threat? Exploration with Hubble, Dawn…and astronauts?

  8. The largest Kuiper Belt Objects, and asteroids (or “protoplanets”) Ceres Vesta Are they planets?

  9. Ceres and Pluto: The “ugly duckling” problem of being the first of an entire class Asteroid Belt Kuiper Belt Discovered 1801-1851 Discovered in 1992 Ceres

  10. Asteroids: typically rocky, with circular orbits between Mars and Jupiter… …but there are some icy “Main Belt Comets”, and Near-Earth Objects Main Asteroid Belt

  11. Hubble images of Ceres reveal roundness, surface features, and colors

  12. Hubble WFPC2 images of asteroid Vesta in May 2007: color composite movie

  13. Hubble WFC3 images of asteroid Vesta in 2010: color composite movie

  14. Dawn will spend several months in polar orbit around Vesta, before leaving for Ceres. Over the last 16 years, Hubble observations have helped refine Vesta’s pole position, which can give Dawn extra time to do science, rather than making orbit adjustments. A more accurate knowledge of the pole position will also help identify when the extreme latitudes will have the best possible solar illumination, and are “ready for their close-up” .

  15. Improved Measurement of asteroid 4 Vesta’s rotational axis orientation Jian-Yang Li,, Peter C. Thomas, Brian Carcich, Max J. Mutchler, Lucy A. McFadden, Christopher T. Russell, Stacy S. Weinstein-Weiss, Marc D. Rayman, Carol A. Raymond , 2010, Icarus

  16. Dawn mission overview • “Star Wars” ion propulsion allows for asteroid-hopping • Launch 27 Sep 2007 • Mars boost 2009 • Orbit Vesta 2011-12 • Orbit Ceres 2015 • Pallas: can’t get there from here (anymore) • Note: New Horizons Pluto flyby July 2015

  17. So…why care about rocks in space? We shall not cease from exploration and the end of all our exploring will be to arrive where we started and know the place for the first time. -- T. S. Eliot

  18. We see evidence of ongoing star formation in our own galaxy and other galaxies These jets indicate a star forming inside this cloud

  19. Our Sun forming from the collapse of a cloud of gas and dust, forms a rotating disk Asteroids and comets are some of the best-preserved “fossils” from the early Solar System

  20. Further collapse within the disk form the icy gas giant planets further out, beyond the “snow line” The rocky terrestrial planets form closer in

  21. There is evidence on Earth that planet formation involved violent collisions and impacts

  22. Since the moon has no weather (erosion), the impact history is preserved much better

  23. So we can surmise that the early Earth had no oceans, and was not hospitable to life

  24. After the heaviest bombardment was over, later asteroid and comet impacts may have delivered water and organic material to Earth – the stuff of life

  25. Water Ice Discovered on Asteroid for First Time By Clara MoskowitzSPACE.com Senior Writer28 April 2010 Water ice has been found on the surface of a nearby asteroid for the first time – a discovery that could help explain how Earth got its oceans. Two teams of researchers independently verified that the asteroid 24 Themis – a large rock hurtling through space in the asteroid belt between Mars and Jupiter – is coated in a layer of frost. They also found that the asteroid contains organic material, including some molecules that might be ingredients for life. The discovery might even provide clues about the origin of water on Earth. "Our data are certainly at least consistent with the idea that you could bring in plenty of water from impacts,“ said Andrew Rivkin of Johns Hopkins University.

  26. Asteroid Scheila: a “Main Belt Comet”In the wee hours of December 11th, University of Arizona astronomer Steve Larson was on cosmic patrol with the Catalina Sky Survey's Schmidt telescope. That's when he noticed something odd about the appearance of the main-belt asteroid 596 Scheila. The asteroid was clearly fuzzy, with a soft glow extending a few arcminutes to the west and north. Other astronomers quickly confirmed the cometary appearance. If Scheila is truly a long-dormant comet, then it's a big one: current estimates put its diameter at 70 miles (113 km). "It's a main-belt comet, although I don't know what type yet," Dave Jewitt explains. He says it could have resulted from an impact (as occurred earlier this year with P/2010 A2) or outgassing (as occurs on 133P/Elst-Pizarro).

  27. The Whole Shebang The Earth (and life on it) has always been directly influenced by events in the larger universe…and always will be

  28. Uh oh! You might want to pay more attention to those space rocks than we did !!!

  29. The dinosaurs got a warning shot…. …before they met their fate Research by Dr. William F. Bottke, Dr. David Vokrouhlicky and Dr. David Nesvorny suggests that the impactor believed to have wiped out the dinosaurs and other life forms on Earth 65 million years ago can been traced back to a breakup event in the main asteroid belt.

  30. A main-belt comet? No, an asteroid collision…

  31. “A recent disruption of the main-belt asteroid P/2010 A2” David Jewitt,Harold Weaver,Jessica Agarwal,MaxMutchler& Michal Drahus,Nature, Volume 467, 14 October 2010

  32. Illustration by Anne Feild, STScI

  33. Big collisions in the early Solar System • Earth-Moon formation • Pluto and moons • Vesta impact: created 50 smaller asteroids, 20% of meteorites… and any moons?

  34. Hubble reveals two new Pluto moons in 2005 Charon, Nix, and Hydra likely formed by collision…so Vesta should have moons too?

  35. dwarf planet asteroid (small solar system body) Hey, no fair! But they are both “proto-planets”

  36. Same initial conditions, but different subsequent evolutions Thomas, P. et al., 2005, “Differentiation of the asteroid Ceres as revealed by its shape”, Nature Letters, Vol 437 Thomas, P. et al., 1997, “Impact excavation on asteroid 4 Vesta: Hubble Space Telescope results”, Science, Vol 277 Vesta’s impact crater, volcanic maria, dry?

  37. So Vesta should have moons, right? Satellite search with Hubble’s WFPC2 camera, and with Dawn as it approaches in July Hill sphere (orbital stability zone)

  38. Rosetta flyby of asteroid 21 Lutetia on 7 July 2010

  39. Hubble moon search for asteroid 21 Lutetia: a cautionary tale An optical “ghost”… not a moon!

  40. Ongoing impacts and near-misses

  41. Comet Shoemaker-Levy 9 impacts Jupiter in July 1994, shortly after the 1st Hubble servicing mission

  42. What if Comet SL9 hit Earth instead of Jupiter? Much less likely, but maybe we should try to understand these events?

  43. Our fears (fueled by sci-fi) This week’s New Yorker magazine

  44. Fireball over Wisconsin on 14 April 2010: caused by an object only ~1 meter in diameter About 100 tons per day impacts the Earth, in small pieces

  45. The animation consists of 34 radar images of near-Earth asteroid 2010 JL33 taken by the Goldstone radio telescope on December 11 and 12, 2011. According to the JPL website, the radar observations reveal that "2010 JL33 is an irregular, elongated object roughly 1.8 kilometers wide that rotates once every nine hours."