Impact Hazard Associated with Large Meteoroids from Disrupted Asteroids and Comets
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Imaginative Geographies of Mars: the Science and Significance of the Red Planet, 1877 - 1910
Copyright by Kristina Maria Doyle Lane 2006 The Dissertation Committee for Kristina Maria Doyle Lane Certifies that this is the approved version of the following dissertation: IMAGINATIVE GEOGRAPHIES OF MARS: THE SCIENCE AND SIGNIFICANCE OF THE RED PLANET, 1877 - 1910 Committee: Ian R. Manners, Supervisor Kelley A. Crews-Meyer Diana K. Davis Roger Hart Steven D. Hoelscher Imaginative Geographies of Mars: The Science and Significance of the Red Planet, 1877 - 1910 by Kristina Maria Doyle Lane, B.A.; M.S.C.R.P. Dissertation Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy The University of Texas at Austin August 2006 Dedication This dissertation is dedicated to Magdalena Maria Kost, who probably never would have understood why it had to be written and certainly would not have wanted to read it, but who would have been very proud nonetheless. Acknowledgments This dissertation would have been impossible without the assistance of many extremely capable and accommodating professionals. For patiently guiding me in the early research phases and then responding to countless followup email messages, I would like to thank Antoinette Beiser and Marty Hecht of the Lowell Observatory Library and Archives at Flagstaff. For introducing me to the many treasures held deep underground in our nation’s capital, I would like to thank Pam VanEe and Ed Redmond of the Geography and Map Division of the Library of Congress in Washington, D.C. For welcoming me during two brief but productive visits to the most beautiful library I have seen, I thank Brenda Corbin and Gregory Shelton of the U.S. -
Copyrighted Material
Index Abulfeda crater chain (Moon), 97 Aphrodite Terra (Venus), 142, 143, 144, 145, 146 Acheron Fossae (Mars), 165 Apohele asteroids, 353–354 Achilles asteroids, 351 Apollinaris Patera (Mars), 168 achondrite meteorites, 360 Apollo asteroids, 346, 353, 354, 361, 371 Acidalia Planitia (Mars), 164 Apollo program, 86, 96, 97, 101, 102, 108–109, 110, 361 Adams, John Couch, 298 Apollo 8, 96 Adonis, 371 Apollo 11, 94, 110 Adrastea, 238, 241 Apollo 12, 96, 110 Aegaeon, 263 Apollo 14, 93, 110 Africa, 63, 73, 143 Apollo 15, 100, 103, 104, 110 Akatsuki spacecraft (see Venus Climate Orbiter) Apollo 16, 59, 96, 102, 103, 110 Akna Montes (Venus), 142 Apollo 17, 95, 99, 100, 102, 103, 110 Alabama, 62 Apollodorus crater (Mercury), 127 Alba Patera (Mars), 167 Apollo Lunar Surface Experiments Package (ALSEP), 110 Aldrin, Edwin (Buzz), 94 Apophis, 354, 355 Alexandria, 69 Appalachian mountains (Earth), 74, 270 Alfvén, Hannes, 35 Aqua, 56 Alfvén waves, 35–36, 43, 49 Arabia Terra (Mars), 177, 191, 200 Algeria, 358 arachnoids (see Venus) ALH 84001, 201, 204–205 Archimedes crater (Moon), 93, 106 Allan Hills, 109, 201 Arctic, 62, 67, 84, 186, 229 Allende meteorite, 359, 360 Arden Corona (Miranda), 291 Allen Telescope Array, 409 Arecibo Observatory, 114, 144, 341, 379, 380, 408, 409 Alpha Regio (Venus), 144, 148, 149 Ares Vallis (Mars), 179, 180, 199 Alphonsus crater (Moon), 99, 102 Argentina, 408 Alps (Moon), 93 Argyre Basin (Mars), 161, 162, 163, 166, 186 Amalthea, 236–237, 238, 239, 241 Ariadaeus Rille (Moon), 100, 102 Amazonis Planitia (Mars), 161 COPYRIGHTED -
Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar End
N9 Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar end Planetary Laboratory The University of Arizona Our overall scientific goal is to survey the solar system to completion -- that is, to find the various populations and to study their statistics, interrelations, and origins. The practical benefit to SERC is that we are finding Earth-approaching asteroids that are accessible for mining. Our system can detect Earth-approachers In the 1-km size range even when they are far away, and can detect smaller objects when they are moving rapidly past Earth. Until Spacewatch, the size range of 6 - 300 meters in diameter for the near-Earth asteroids was unexplored. This important region represents the transition between the meteorites and the larger observed near-Earth asteroids (Rabinowitz 1992). One of our Spacewatch discoveries, 1991 VG, may be representative of a new orbital class of object. If it is really a natural object, and not man-made, its orbital parameters are closer to those of the Earth than we have seen before; its delta V is the lowest of all objects known thus far (J. S. Lewis, personal communication 1992). We may expect new discoveries as we continue our surveying, with fine-tuning of the techniques. III-12 Introduction The data accumulated in the following tables are the result of continuing observation conducted as a part of the Spacewatch program. T. Gehrels is the Principal Investigator and also one of the three observers, with J.V. Scotti and D.L Rabinowitz, each observing six nights per month. R.S. McMillan has been Co-Principal Investigator of our CCD-scanning since its inception; he coordinates optical, mechanical, and electronic upgrades. -
For Immediate Release
FOR IMMEDIATE RELEASE ASTRONAUTS, EXPERTS, AND SPACE AGENCIES DISCUSS ASTEROIDS, OPPORTUNITIES, AND RISKS ON ASTEROID DAY, 30 JUNE LUXEMBOURG, 22 June 2020 /PRNewswire/ -- The Asteroid Foundation returns with Asteroid Day LIVE Digital from Luxembourg. This year, the event is a fully digital celebration of asteroid science and exploration. Panel discussions and one-on-one interviews with astronauts and world experts will be broadcast on 30 June 2020. Each year Asteroid Day presents the public with a snap-shot of cutting-edge asteroid research from the largest telescopes on Earth to some of the most ambitious space missions. Topics of discussion this year include the acceleration in the rate of our asteroid discoveries and why it is set to accelerate even faster, the imminent arrival of samples from asteroid Ryugu and Bennu, the exciting preparations for the joint US-Europe mission to binary asteroid Didymos, and much more. Asteroids are the leftover remnants of the birth of the planets in the Solar System, and many are the shattered fragments of these diminutive proto-planets that never made it to maturity. “Asteroid exploration missions tell us about the birth of our own planet and reveal how asteroids can serve astronauts as stepping stones to Mars,” says Tom Jones, PhD, veteran astronaut and planetary scientist, and Asteroid Day Expert Panel member. Each asteroid is an individual with its own story to tell. And that’s what Asteroid Day is all about: bringing those stories to the widest audience possible. “Space and science have been an endless source of inspiration for SES! This is one of the reasons why we and our partners continue to do extraordinary things in space to deliver amazing experiences everywhere on earth,” says Ruy Pinto, Chief Technology Officer at SES. -
Martian Crater Morphology
ANALYSIS OF THE DEPTH-DIAMETER RELATIONSHIP OF MARTIAN CRATERS A Capstone Experience Thesis Presented by Jared Howenstine Completion Date: May 2006 Approved By: Professor M. Darby Dyar, Astronomy Professor Christopher Condit, Geology Professor Judith Young, Astronomy Abstract Title: Analysis of the Depth-Diameter Relationship of Martian Craters Author: Jared Howenstine, Astronomy Approved By: Judith Young, Astronomy Approved By: M. Darby Dyar, Astronomy Approved By: Christopher Condit, Geology CE Type: Departmental Honors Project Using a gridded version of maritan topography with the computer program Gridview, this project studied the depth-diameter relationship of martian impact craters. The work encompasses 361 profiles of impacts with diameters larger than 15 kilometers and is a continuation of work that was started at the Lunar and Planetary Institute in Houston, Texas under the guidance of Dr. Walter S. Keifer. Using the most ‘pristine,’ or deepest craters in the data a depth-diameter relationship was determined: d = 0.610D 0.327 , where d is the depth of the crater and D is the diameter of the crater, both in kilometers. This relationship can then be used to estimate the theoretical depth of any impact radius, and therefore can be used to estimate the pristine shape of the crater. With a depth-diameter ratio for a particular crater, the measured depth can then be compared to this theoretical value and an estimate of the amount of material within the crater, or fill, can then be calculated. The data includes 140 named impact craters, 3 basins, and 218 other impacts. The named data encompasses all named impact structures of greater than 100 kilometers in diameter. -
Arxiv:2001.00125V1 [Astro-Ph.EP] 1 Jan 2020
Draft version January 3, 2020 Typeset using LATEX default style in AASTeX61 SIZE AND SHAPE CONSTRAINTS OF (486958) ARROKOTH FROM STELLAR OCCULTATIONS Marc W. Buie,1 Simon B. Porter,1 et al. 1Southwest Research Institute 1050 Walnut St., Suite 300, Boulder, CO 80302 USA To be submitted to Astronomical Journal, Version 1.1, 2019/12/30 ABSTRACT We present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by SOFIA with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 Aug 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 ± 0.0005 hours. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies. -
Amateur Observers Find an Asteroid's Moon
Amateur Observers Find an Asteroid’s Moon By: Kelly Beatty | July 14, 2017 A team of amateurs observers, some armed with just 3-inch telescopes, have found that the main-belt asteroid 113 Amalthea probably has a small companion. Each year, amateur astronomers get worldwide predictions for hundreds of events during which a distant asteroid briefly occults (hides) a star. But some of these cover-ups — like the one involving asteroid 113 Amalthea last March 14th — are anticipated more eagerly than others. That date has been circled on Paul Maley's calendar for about 8 months. A retired NASA staffer and a key member of the International Occultation Timing Association, last year Maley started enlisting amateur observers in Texas to observe the occultation of a 10th-magnitude star by 13th-magnitude Amalthea. And all that planning paid off, because the observing team has discovered that this asteroid probably has a small satellite. It's a robust "probably." As detailed in the IAU's Electronic Telegram 4413, issued on July 12th, a "fence" of 10 observing sites spread across the occultation's predicted path yielded seven positive occultations and three "misses." One of those misses, by Sam Insana in Gila Bend, Arizona, fell between five positive occultation tracks to his north and two to his south. It's colored orange in the diagram below: These lines represent the projected paths of a 10th-magnitude star recorded by observers on March 14, 2017, as the star passed behind the asteroid Amalthea. The small brown circle just below the yellow oval correspond to the location of the asteroid's moon at the time. -
Using Resources from Near-Earth Space
USING RESOURCES FROM NEAR-EARTH SPACE JOHN S. LEWIS University of Arizona DAVIDS. McKAY NASA Johnson Space Center and BENTON C. CLARK Martin Marietta Civil Space & Communications The parts of the solar system that are most accessible from Earth (the Moon, the near Earth asteroids, and Mars and its moons) are rich in materials of great potential value to humanity. Immediate uses of these resources to manufacture propellants, structural metals, refractories, life-support fluids and glass can support future large-scale space acitivites. In the longterm, non-terrestrial sources of rare materials and energy may be of great importance here on Earth. I. INTRODUCTION Space activities have become so much a part of modem life that they are almost invisible. We are aware how important communications satellite relays are for inexpensive long-distance telephone calls and television news broadcast, and we see the color images of Earth's cloud cover in the weather reports on TV. But we are usually not aware that the commercial airplane in which we fly or the ferry we ride locates itself by using navigation satellites 12,000 miles above our heads. We may never hear that the Soviet Union launched several satellites each year dedicated to assessing the American, Canadian, and Argentine wheat crops to help plan their grain purchases. We may be even more astonished to know that the truck we just passed on the highway is being tracked by a satellite, or that the strategic balance between the great powers has long been monitored based on photographic, electronic imaging, radar, infrared, and signal monitoring from space. -
JEM-EUSO: Meteor and Nuclearite Observations
Exp Astron DOI 10.1007/s10686-014-9375-4 ORIGINAL ARTICLE JEM-EUSO: Meteor and nuclearite observations M. Bertaina A. Cellino F. Ronga The JEM-EUSO· Collaboration· · Received: 22 August 2013 / Accepted: 24 February 2014 ©SpringerScience+BusinessMediaDordrecht2014 Abstract Meteor and fireball observations are key to the derivation of both the inven- tory and physical characterization of small solar system bodies orbiting in the vicinity of the Earth. For several decades, observation of these phenomena has only been possible via ground-based instruments. The proposed JEM-EUSO mission has the potential to become the first operational space-based platform to share this capabil- ity. In comparison to the observation of extremely energetic cosmic ray events, which is the primary objective of JEM-EUSO, meteor phenomena are very slow, since their typical speeds are of the order of a few tens of km/sec (whereas cosmic rays travel at light speed). The observing strategy developed to detect meteors may also be applied to the detection of nuclearites, which have higher velocities, a wider range of possible trajectories, but move well below the speed of light and can therefore be considered as slow events for JEM-EUSO. The possible detection of nuclearites greatly enhances the scientific rationale behind the JEM-EUSO mission. Keywords Meteors Nuclearites JEM-EUSO Space detectors · · · M. Bertaina (!) Dipartimento di Fisica, Universit`adiTorino,INFNTorino,viaP.Giuria1,10125Torino,Italy e-mail: [email protected] A. Cellino (!) INAF-Osservatorio Astrofisico di Torino, Strada Osservatorio 20, 10025 Pino Torinese (TO), Italy e-mail: [email protected] F. Ronga (!) Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati, Via E. -
Abstracts of the 50Th DDA Meeting (Boulder, CO)
Abstracts of the 50th DDA Meeting (Boulder, CO) American Astronomical Society June, 2019 100 — Dynamics on Asteroids break-up event around a Lagrange point. 100.01 — Simulations of a Synthetic Eurybates 100.02 — High-Fidelity Testing of Binary Asteroid Collisional Family Formation with Applications to 1999 KW4 Timothy Holt1; David Nesvorny2; Jonathan Horner1; Alex B. Davis1; Daniel Scheeres1 Rachel King1; Brad Carter1; Leigh Brookshaw1 1 Aerospace Engineering Sciences, University of Colorado Boulder 1 Centre for Astrophysics, University of Southern Queensland (Boulder, Colorado, United States) (Longmont, Colorado, United States) 2 Southwest Research Institute (Boulder, Connecticut, United The commonly accepted formation process for asym- States) metric binary asteroids is the spin up and eventual fission of rubble pile asteroids as proposed by Walsh, Of the six recognized collisional families in the Jo- Richardson and Michel (Walsh et al., Nature 2008) vian Trojan swarms, the Eurybates family is the and Scheeres (Scheeres, Icarus 2007). In this theory largest, with over 200 recognized members. Located a rubble pile asteroid is spun up by YORP until it around the Jovian L4 Lagrange point, librations of reaches a critical spin rate and experiences a mass the members make this family an interesting study shedding event forming a close, low-eccentricity in orbital dynamics. The Jovian Trojans are thought satellite. Further work by Jacobson and Scheeres to have been captured during an early period of in- used a planar, two-ellipsoid model to analyze the stability in the Solar system. The parent body of the evolutionary pathways of such a formation event family, 3548 Eurybates is one of the targets for the from the moment the bodies initially fission (Jacob- LUCY spacecraft, and our work will provide a dy- son and Scheeres, Icarus 2011). -
Radar Images Provide Details on Halloween Asteroid 4 November 2015
Radar images provide details on Halloween asteroid 4 November 2015 California, to transmit high-power microwaves toward the asteroid. The signal bounced off the asteroid, and its radar echoes were received by the National Radio Astronomy Observatory's (NRAO) 100-meter (330-foot) Green Bank Telescope in West Virginia. The radar images achieve a spatial resolution as fine as 13 feet (4 meters) per pixel. The radar images were taken as the asteroid flew past Earth on October 31 at 1 p.m. EDT at about 1.3 lunar distances (300,000 miles, or 480,000 kilometers) from Earth. Asteroid 2015 TB145 is spherical in shape and approximately 2,000 feet (600 meters) in diameter. "The radar images of asteroid 2015 TB145 show Asteroid 2015 TB145 is depicted in eight individual radar portions of the surface not seen previously and images collected on Oct. 31, 2015 between 5:55 a.m. PDT (8:55 a.m. EDT) and 6:08 a.m. PDT (9:08 a.m. reveal pronounced concavities, bright spots that EDT). At the time the radar images were taken, the might be boulders, and other complex features that asteroid was between 440,000 miles (710,000 could be ridges," said Lance Benner of NASA's Jet kilometers) and about 430,000 miles (690,000 Propulsion Laboratory in Pasadena, California, who kilometers) distant. Asteroid 2015 TB145 safely flew past leads NASA's asteroid radar research program. Earth on Oct. 31, at 10:00 a.m. PDT (1 p.m. EDT) at "The images look distinctly different from the about 1.3 lunar distances (300,000 miles, 480,000 Arecibo radar images obtained on October 30 and kilometers). -
Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law James A
Hastings International and Comparative Law Review Volume 42 Article 2 Number 1 Winter 2019 Winter 2019 Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law James A. Green Follow this and additional works at: https://repository.uchastings.edu/ hastings_international_comparative_law_review Part of the Comparative and Foreign Law Commons, and the International Law Commons Recommended Citation James A. Green, Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law, 42 Hastings Int'l & Comp.L. Rev. 1 (2019). Available at: https://repository.uchastings.edu/hastings_international_comparative_law_review/vol42/iss1/2 This Article is brought to you for free and open access by the Law Journals at UC Hastings Scholarship Repository. It has been accepted for inclusion in Hastings International and Comparative Law Review by an authorized editor of UC Hastings Scholarship Repository. Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law BY JAMES A. GREEN ABSTRACT The risk of a large Near-Earth Object (NEO), such as an asteroid, colliding with the Earth is low, but the consequences of that risk manifesting could be catastrophic. Recent years have witnessed an unprecedented increase in global political will in relation to NEO preparedness, following the meteoroid impact in Chelyabinsk, Russia in 2013. There also has been an increased focus amongst states on the possibility of using nuclear detonation to divert or destroy a collision- course NEO—something that a majority of scientific opinion now appears to view as representing humanity’s best, or perhaps only, option in extreme cases. Concurrently, recent developments in nuclear disarmament and the de-militarization of space directly contradict the proposed “nuclear option” for planetary defense.