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Mission to Jupiter
This book attempts to convey the creativity, Project A History of the Galileo Jupiter: To Mission The Galileo mission to Jupiter explored leadership, and vision that were necessary for the an exciting new frontier, had a major impact mission’s success. It is a book about dedicated people on planetary science, and provided invaluable and their scientific and engineering achievements. lessons for the design of spacecraft. This The Galileo mission faced many significant problems. mission amassed so many scientific firsts and Some of the most brilliant accomplishments and key discoveries that it can truly be called one of “work-arounds” of the Galileo staff occurred the most impressive feats of exploration of the precisely when these challenges arose. Throughout 20th century. In the words of John Casani, the the mission, engineers and scientists found ways to original project manager of the mission, “Galileo keep the spacecraft operational from a distance of was a way of demonstrating . just what U.S. nearly half a billion miles, enabling one of the most technology was capable of doing.” An engineer impressive voyages of scientific discovery. on the Galileo team expressed more personal * * * * * sentiments when she said, “I had never been a Michael Meltzer is an environmental part of something with such great scope . To scientist who has been writing about science know that the whole world was watching and and technology for nearly 30 years. His books hoping with us that this would work. We were and articles have investigated topics that include doing something for all mankind.” designing solar houses, preventing pollution in When Galileo lifted off from Kennedy electroplating shops, catching salmon with sonar and Space Center on 18 October 1989, it began an radar, and developing a sensor for examining Space interplanetary voyage that took it to Venus, to Michael Meltzer Michael Shuttle engines. -
Mariner to Mercury, Venus and Mars
NASA Facts National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, CA 91109 Mariner to Mercury, Venus and Mars Between 1962 and late 1973, NASA’s Jet carry a host of scientific instruments. Some of the Propulsion Laboratory designed and built 10 space- instruments, such as cameras, would need to be point- craft named Mariner to explore the inner solar system ed at the target body it was studying. Other instru- -- visiting the planets Venus, Mars and Mercury for ments were non-directional and studied phenomena the first time, and returning to Venus and Mars for such as magnetic fields and charged particles. JPL additional close observations. The final mission in the engineers proposed to make the Mariners “three-axis- series, Mariner 10, flew past Venus before going on to stabilized,” meaning that unlike other space probes encounter Mercury, after which it returned to Mercury they would not spin. for a total of three flybys. The next-to-last, Mariner Each of the Mariner projects was designed to have 9, became the first ever to orbit another planet when two spacecraft launched on separate rockets, in case it rached Mars for about a year of mapping and mea- of difficulties with the nearly untried launch vehicles. surement. Mariner 1, Mariner 3, and Mariner 8 were in fact lost The Mariners were all relatively small robotic during launch, but their backups were successful. No explorers, each launched on an Atlas rocket with Mariners were lost in later flight to their destination either an Agena or Centaur upper-stage booster, and planets or before completing their scientific missions. -
Mercury Redux
FEATURE Mercury redux In January 2008, 33 years after Mariner 10 fl ew past the solar system’s innermost planet, MESSENGER crossed Mercury’s magnetosphere. Ancient volcanoes, contractional faults, and a rich soup of exospheric ions give clues to Mercury’s structure and dynamical evolution. Th e Mercury fl yby of the MESSENGER two have not been ruled out, but for those (Mercury surface, space environment, mechanisms shorter-wavelength magnetic geochemistry and ranging) probe was the features would be expected, which were not fi rst of three braking manoeuvres for the observed during the MESSENGER fl yby1. spacecraft , in preparation for its insertion Recent libration observations that require into a polar orbit in 2011. Th e probe a partially molten core11, and the limited achieved the closest approach (201 km) of contraction of Mercury, which implies a Mercury’s surface yet, and took a variety largely molten core, favour a convective of measurements in the magnetosphere, dynamo origin for Mercury’s magnetic fi eld. exosphere and on Mercury’s surface. Some Although Mercury’s magnetosphere of the fi rst results of the MESSENGER looks like a miniature version of Earth’s, mission1–6 reveal Mercury as a planet with Mercury’s relatively weak magnetic richly interconnected dynamics, from fi eld implies that its dynamo must work the dynamo in its molten outer core, a diff erently from that of the Earth. Th e crust and surface with great lobate faults geodynamo, which gives the Earth its and relatively young volcanoes, to a strong magnetic fi eld, is thought to operate magnetosphere that interacts with the core in a magnetostrophic regime in which the dynamo and the interplanetary solar wind. -
Torrid Mercury's Icy Poles
Fire and ice The MESSENGER spacecraft reveals water ice lurking in Torrid Mercury’s icy poles deeply shadowed craters near the innermost planet’s poles. by James Oberg Color explodes from Mercury’s surface in this enhanced-color mosaic. The yellow and orange hues signify relatively young volcanic plains, while blue represents older terrain. The planet’s equator runs horizon- he saga of water ice hiding in GEochemistry, and Ranging — started Planetary scientist David Paige of the works best when good observations are tally through the center of this image; the poles lie at top and bottom. NASA/JHUAPL/CIW the shadows on Mercury ranks orbiting Mercury in March 2011 and has University of California, Los Angeles, a guided by theory.” among the most fascinating been returning reams of data ever since. participating scientist on the MESSENGER During the past several decades, scien- chapters in the history of plan- The discovery of ice contains its own sur- project, stresses the wider significance of tists have come to realize that a conspiracy to the planet nearly 40 years ago, could not Untangling Mercury’s web etary exploration. And the prises and new mysteries. the ice story. “The Mercury discoveries of freak accidents involving Mercury’s make the observations necessary to prove It took centuries for astronomers to deci- story didn’t end a year ago Scientists had suspected for decades that demonstrate the power of theory and motion and orientation had created small the case. Still, radar observations from pher Mercury’s physical and dynamic when scientists using NASA’s water ice might survive in corners of the imagination in astronomy and planetary regions on the planet’s surface where it Earth did detect unusually reflective characteristics and to understand their MESSENGER spacecraft con- solar system’s innermost world. -
NASA and Planetary Exploration
**EU5 Chap 2(263-300) 2/20/03 1:16 PM Page 263 Chapter Two NASA and Planetary Exploration by Amy Paige Snyder Prelude to NASA’s Planetary Exploration Program Four and a half billion years ago, a rotating cloud of gaseous and dusty material on the fringes of the Milky Way galaxy flattened into a disk, forming a star from the inner- most matter. Collisions among dust particles orbiting the newly-formed star, which humans call the Sun, formed kilometer-sized bodies called planetesimals which in turn aggregated to form the present-day planets.1 On the third planet from the Sun, several billions of years of evolution gave rise to a species of living beings equipped with the intel- lectual capacity to speculate about the nature of the heavens above them. Long before the era of interplanetary travel using robotic spacecraft, Greeks observing the night skies with their eyes alone noticed that five objects above failed to move with the other pinpoints of light, and thus named them planets, for “wan- derers.”2 For the next six thousand years, humans living in regions of the Mediterranean and Europe strove to make sense of the physical characteristics of the enigmatic planets.3 Building on the work of the Babylonians, Chaldeans, and Hellenistic Greeks who had developed mathematical methods to predict planetary motion, Claudius Ptolemy of Alexandria put forth a theory in the second century A.D. that the planets moved in small circles, or epicycles, around a larger circle centered on Earth.4 Only partially explaining the planets’ motions, this theory dominated until Nicolaus Copernicus of present-day Poland became dissatisfied with the inadequacies of epicycle theory in the mid-sixteenth century; a more logical explanation of the observed motions, he found, was to consider the Sun the pivot of planetary orbits.5 1. -
Large Impact Basins on Mercury: Global Distribution, Characteristics, and Modification History from MESSENGER Orbital Data Caleb I
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, E00L08, doi:10.1029/2012JE004154, 2012 Large impact basins on Mercury: Global distribution, characteristics, and modification history from MESSENGER orbital data Caleb I. Fassett,1 James W. Head,2 David M. H. Baker,2 Maria T. Zuber,3 David E. Smith,3,4 Gregory A. Neumann,4 Sean C. Solomon,5,6 Christian Klimczak,5 Robert G. Strom,7 Clark R. Chapman,8 Louise M. Prockter,9 Roger J. Phillips,8 Jürgen Oberst,10 and Frank Preusker10 Received 6 June 2012; revised 31 August 2012; accepted 5 September 2012; published 27 October 2012. [1] The formation of large impact basins (diameter D ≥ 300 km) was an important process in the early geological evolution of Mercury and influenced the planet’s topography, stratigraphy, and crustal structure. We catalog and characterize this basin population on Mercury from global observations by the MESSENGER spacecraft, and we use the new data to evaluate basins suggested on the basis of the Mariner 10 flybys. Forty-six certain or probable impact basins are recognized; a few additional basins that may have been degraded to the point of ambiguity are plausible on the basis of new data but are classified as uncertain. The spatial density of large basins (D ≥ 500 km) on Mercury is lower than that on the Moon. Morphological characteristics of basins on Mercury suggest that on average they are more degraded than lunar basins. These observations are consistent with more efficient modification, degradation, and obliteration of the largest basins on Mercury than on the Moon. This distinction may be a result of differences in the basin formation process (producing fewer rings), relaxation of topography after basin formation (subduing relief), or rates of volcanism (burying basin rings and interiors) during the period of heavy bombardment on Mercury from those on the Moon. -
First Look at Mercury
PLANETARY SCIENCE Mariner 10 was launched to Mercury by way of Venus on November 3, 1973. It was not the first probe to visit Venus. Both the United States and the Soviet Union previously have sent probes to that mysterious, cloud-shrouded planet. However, Mariner 10 was the first to photographically explore the close-up appearance of the planet, and did so both in visibIe and in ultraviolet light. And Mariner 10 was the first probe of any kind to penetrate interplanetary space beyond the orbit of Venus and to achieve a close look at the planet Mercury. First Look Why go to Mercury? Who needs it? There basically are two kinds of reasons. The first is simple and profound and at Mercury difficult to quantify: The very act of exploration is a positive, cultural activity. No one knows what is going to be found. Finding out what Mercury, what Mars, or BRUCE C. MURRAY what the moon is really like, enlarges the consciousness of all the people who partake of that new reality. TV pictures are of special importance because they provide a way both for the scientist to discover features and concepts he could not have imagined and for the public to directly appreciate and participate in the exploration of a new world. Why go to Mercury? Who needs it? But there are more specific scientific objectives as well. For Mercury, the basic-and anomalous-scientific fact is A planetary scientist that it is a very dense planet: It contains a great amount of tells what the voyage mass for its size. -
Mariner 10 Observations of Field-Aligned Currents at Mercury
Planet. Space Sci., Vol. 45, No. 1, pp. 133-141, 1997 Pergamon #I? 1997 Published bv Elsevier Science Ltd P&ted in Great Brit& All rights reserved 0032-0633/97 $17.00+0.00 PII: S0032-0633(96)00104-3 Mariner 10 observations of field-aligned currents at Mercury J. A. Slavin,’ J. C. J. Owen,’ J. E. P. Connerney’ and S. P. Christon ‘Laboratory for Extraterrestrial Physics, NASA/GSFC, Greenbelt, MD 20771, U.S.A. ‘Astronomy Unit, Queen Mary and Westfield College, London, U.K. 3Department of Physics, University of Maryland, College Park, MD 20742, U.S.A. Received 5 October 1995; revised 11 April 1996; accepted 13 April 1996 magnetic field at Mercury with a dipole moment of about 300nT R& (see review by Connerney and Ness (1988)). This magnetic field is sufficient to stand-off the average solar wind at an altitude of about 1 RM as depicted in Fig. 1 (see review by Russell et al. (1988)). For the purposes of comparison the diameter of the Earth is indicated at the bottom of the figure (i.e. 1 RE = 6380 km ; 1 RM = 2439 km). Whether or not the solar wind is ever able to compress and/or erode the dayside magnetosphere to the point where solar wind ions could directly impact the surface remains a topic of considerable controversy (Siscoe and Christopher, 1975 ; Slavin and Holzer, 1979 ; Hood and Schubert, 1979; Suess and Goldstein, 1979; Goldstein et al., 1981). Overall, the basic morphology of this small mag- netosphere appears quite similar to that of the Earth. -
Mysterious Mercury Bepicolumbo Heads for the World of Ice and Fire
A Digital Supplement to Astronomy Insights Astronomy Magazine © 2018 Kalmbach Media Mysterious Mercury BepiColumbo Heads for the World of Ice and Fire Dcember 2018 • Astronomy.com Voyage to a world Color explodes from Mercury’s surface in this enhanced-color mosaic taken through several filters. The yellow and orange hues signify relatively young plains likely formed when fluid lavas erupted from volcanoes. Medium- and dark-blue regions are older terrain, while the light-blue and white streaks represent fresh material excavated from relatively recent impacts. ALL IMAGES, UNLESS OTHERWISE NOTED: NASA/JHUAPL/CIW 2 ASTRONOMY INSIGHTS • DECEMBER 2018 A world of both fire and ice, Mercury excites and confounds scientists. The BepiColombo probe aims to make sense of this mysterious world. by Ben Evans of extremesWWW.ASTRONOMY.COM 3 Mercury is a land of contrasts. The solar system’s smallest planet boasts the largest core relative to its size. Temperatures at noon can soar as high as 800 degrees Fahrenheit (425 degrees Celsius) — hot enough to melt lead — but dip as low as –290 F (–180 C) before dawn. Mercury resides nearest the Sun, and it has the most eccentric orbit. At its closest, the planet lies only 29 mil- lion miles (46 million kilometers) from the Sun — less than one-third Earth’s distance — but swings out as far as 43 million miles (70 million km). Its rapid movement across our sky earned it a reputation among ancient skywatchers as the fleet-footed messenger of the gods: Italian scientist Giuseppe “Bepi” Colombo helped develop a technique for sending a space Hermes to the Greeks and Mercury to the Romans. -
Mercury Orbit Insertion March 18, 2011 UTC (March 17, 2011 EDT)
Mercury Orbit Insertion March 18, 2011 UTC (March 17, 2011 EDT) A NASA Discovery Mission Media Contacts NASA Headquarters Policy/Program Management Dwayne C. Brown (202) 358-1726 [email protected] The Johns Hopkins University Applied Physics Laboratory Mission Management, Spacecraft Operations Paulette W. Campbell (240) 228-6792 or (443) 778-6792 [email protected] Carnegie Institution of Washington Principal Investigator Institution Tina McDowell (202) 939-1120 [email protected] Mission Overview Key Spacecraft Characteristics MESSENGER is a scientific investigation . Redundant major systems provide critical backup. of the planet Mercury. Understanding . Passive thermal design utilizing ceramic-cloth Mercury, and the forces that have shaped sunshade requires no high-temperature electronics. it, is fundamental to understanding the . Fixed phased-array antennas replace a deployable terrestrial planets and their evolution. high-gain antenna. The MESSENGER (MErcury Surface, Space . Custom solar arrays produce power at safe operating ENvironment, GEochemistry, and Ranging) temperatures near Mercury. spacecraft will orbit Mercury following three flybys of that planet. The orbital phase will MESSENGER is designed to answer six use the flyby data as an initial guide to broad scientific questions: perform a focused scientific investigation of . Why is Mercury so dense? this enigmatic world. What is the geologic history of Mercury? MESSENGER will investigate key . What is the nature of Mercury’s magnetic field? scientific questions regarding Mercury’s . What is the structure of Mercury’s core? characteristics and environment during . What are the unusual materials at Mercury’s poles? these two complementary mission phases. What volatiles are important at Mercury? Data are provided by an optimized set of miniaturized space instruments and the MESSENGER provides: spacecraft tele commun ications system. -
Shallow Basins on Mercury: Evidence of Relaxation?
Earth and Planetary Science Letters 285 (2009) 355–363 Contents lists available at ScienceDirect Earth and Planetary Science Letters journal homepage: www.elsevier.com/locate/epsl Shallow basins on Mercury: Evidence of relaxation? P. Surdas Mohit a,b,⁎, Catherine L. Johnson a,b, Olivier Barnouin-Jha c, Maria T. Zuber d, Sean C. Solomon e a Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, BC, Canada V6T 1Z4 b Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, La Jolla, CA 92093, USA c The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA d Department of Earth, Atmospheric, and Planetary Sciences, Massachussetts Institute of Technology, Cambridge, MA 02139, USA e Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA article info abstract Article history: Stereo-derived topographic models have shown that the impact basins Beethoven and Tolstoj on Mercury are Accepted 15 April 2009 shallow for their size, with depths of 2.5 and 2 (±0.7) km, respectively, while Caloris basin has been Available online 28 May 2009 estimated to be 9 (±3) km deep on the basis of photoclinometric measurements. We evaluate the depths of Editor: T. Spohn Beethoven and Tolstoj in the context of comparable basins on other planets and smaller craters on Mercury, using data from Mariner 10 and the first flyby of the MESSENGER spacecraft. We consider three scenarios that fi Keywords: might explain the anomalous depths of these basins: (1) volcanic in lling, (2) complete crustal excavation, Mercury and (3) viscoelastic relaxation. None of these can be ruled out, but the fill scenario would imply a thick MESSENGER lithosphere early in Mercury's history and the crustal-excavation scenario a pre-impact crustal thickness of Caloris 15–55 km, depending on the density of the crust, in the area of Beethoven and Tolstoj. -
Lunar Science Workshop
National Aeronautics and Space Administration LUNAR SCIENCE WORKSHOP NASA ADVISORY COUNCIL WORKSHOP ON SCIENCE ASSOCIATED WITH THE LUNAR EXPLORATION ARCHITECTURE FEBRUARY 27–MARCH 2, 2007 • TEMPE, ARIZONA TABLE OF CONTENTS Foreword . 3 Organizing Committee . 7 Executive Summary and Key Assessments . 9 Introduction and Overview of the Workshop . 17 The Vision for Space Exploration and the Role of Science . 21 The Global Exploration Strategy . 23 The Lunar Exploration Architecture . 27 Assessment of Potential Science Activities . 31 Findings of the Workshop . 35 Astrophysics . 36 Earth Science . 39 Heliophysics . 41 Planetary Protection . 43 Planetary Science . 46 Outreach Messages and Highlights of the Workshop . 53 Concluding Statement . 57 Appendices: Science Subcommittee Workshop Findings . 59 Appendix 1: Astrophysics . 59 Appendix 2: Earth Science . 67 Appendix 3: Heliophysics . 83 Appendix 4: Planetary Protection . 91 Appendix 5: Planetary Science . 99 Appendix 6: Detailed Program . 119 Appendix 7: List of Acronyms Used in the Report . 131 2 FOREWORD From February 27 through March 2, 2007, the NASA Advisory Council Science Committee conducted the “Workshop on Science Associated with the Lunar Exploration Architecture” at the Fiesta Inn Resort in Tempe, Arizona . The workshop was planned and timed to feed into ongoing efforts by NASA’s Lunar Architecture Team (LAT) to develop an exploration architecture for the return of humans to the Moon by 2020 in accordance with the Vision for Space Exploration (VSE) and the NASA Authorization Act of 2005 . The goals of the workshop were to: (1) ensure that NASA’s exploration strategy, architecture, and hardware development enable the best and appropriately integrated science activities in association with the return of humans to the Moon and subsequent exploration of Mars; (2) bring diverse constituencies together to hear, discuss, and assess science activities and priorities for science enabled by the exploration architecture; and (3) identify needed science programs and technology developments.