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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. -
Elemental Abundances of Low-Mass Stars in the Young Clusters 25 Ori
Astronomy & Astrophysics manuscript no. Biazzoetal˙Mar2011˙noref c ESO 2018 October 16, 2018 Elemental abundances of low-mass stars in the young clusters 25 Ori and λ Ori⋆ K. Biazzo1, S. Randich1, F. Palla1, and C. Brice˜no2 1 INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy 2 CIDA - Centro de Investigaciones de Astronom`ıa, Apartado Postal 264, M´erida 5101-A, Venezuela Received / accepted ABSTRACT Aims. We aim to derive the chemical pattern of the young clusters 25 Orionis and λ Orionis through homogeneous and accurate measurements of elemental abundances. Methods. We present flames/uves observations of a sample of 14 K-type targets in the 25 Ori and λ Ori clusters; we measure their radial velocities, in order to confirm cluster membership. We derive stellar parameters and abundances of Fe, Na, Al, Si, Ca, Ti, and Ni using the code MOOG. Results. All the 25 Ori stars are confirmed cluster members without evidence of binarity; in λ Ori we identify one non-member and one candidate single-lined binary star. We find an average metallicity [Fe/H]=−0.05 ± 0.05 for 25 Ori, where the error is the 1σ standard deviation from the average. λ Ori members have a mean iron abundance value of 0.01 ± 0.01. The other elements show close-to-solar ratios and no star-to-star dispersion. Conclusions. Our results, along with previous metallicity determinations in the Orion complex, evidence a small but detectable dispersion in the [Fe/H] distribution of the complex. This appears to be compatible with large-scale star formation episodes and initial non-uniformity in the pre-cloud medium. -
Caverns Measureless to Man: Interdisciplinary Planetary Science & Technology Analog Research Underwater Laser Scanner Survey (Quintana Roo, Mexico)
Caverns Measureless to Man: Interdisciplinary Planetary Science & Technology Analog Research Underwater Laser Scanner Survey (Quintana Roo, Mexico) by Stephen Alexander Daire A Thesis Presented to the Faculty of the USC Graduate School University of Southern California In Partial Fulfillment of the Requirements for the Degree Master of Science (Geographic Information Science and Technology) May 2019 Copyright © 2019 by Stephen Daire “History is just a 25,000-year dash from the trees to the starship; and while it’s going on its wild and woolly but it’s only like that, and then you’re in the starship.” – Terence McKenna. Table of Contents List of Figures ................................................................................................................................ iv List of Tables ................................................................................................................................. xi Acknowledgements ....................................................................................................................... xii List of Abbreviations ................................................................................................................... xiii Abstract ........................................................................................................................................ xvi Chapter 1 Planetary Sciences, Cave Survey, & Human Evolution................................................. 1 1.1. Topic & Area of Interest: Exploration & Survey ....................................................................12 -
Fy10 Budget by Program
AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................ -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
The Maunder Minimum and the Variable Sun-Earth Connection
The Maunder Minimum and the Variable Sun-Earth Connection (Front illustration: the Sun without spots, July 27, 1954) By Willie Wei-Hock Soon and Steven H. Yaskell To Soon Gim-Chuan, Chua Chiew-See, Pham Than (Lien+Van’s mother) and Ulla and Anna In Memory of Miriam Fuchs (baba Gil’s mother)---W.H.S. In Memory of Andrew Hoff---S.H.Y. To interrupt His Yellow Plan The Sun does not allow Caprices of the Atmosphere – And even when the Snow Heaves Balls of Specks, like Vicious Boy Directly in His Eye – Does not so much as turn His Head Busy with Majesty – ‘Tis His to stimulate the Earth And magnetize the Sea - And bind Astronomy, in place, Yet Any passing by Would deem Ourselves – the busier As the Minutest Bee That rides – emits a Thunder – A Bomb – to justify Emily Dickinson (poem 224. c. 1862) Since people are by nature poorly equipped to register any but short-term changes, it is not surprising that we fail to notice slower changes in either climate or the sun. John A. Eddy, The New Solar Physics (1977-78) Foreword By E. N. Parker In this time of global warming we are impelled by both the anticipated dire consequences and by scientific curiosity to investigate the factors that drive the climate. Climate has fluctuated strongly and abruptly in the past, with ice ages and interglacial warming as the long term extremes. Historical research in the last decades has shown short term climatic transients to be a frequent occurrence, often imposing disastrous hardship on the afflicted human populations. -
The Southern Flanking Fields of the 25 Orionis Group
The Southern Flanking Fields of the 25 Orionis Group Peregrine M. McGehee1 ABSTRACT The stellar group surrounding the Be (B1Vpe) star 25 Orionis was discov- ered to be a pre-main-sequence population by the Centro de Investigaciones de Astronomia (CIDA) Orion Variability Survey and subsequent spectroscopy. We analyze Sloan Digital Sky Survey multi-epoch photometry to map the southern extent of the 25 Ori group and to characterize its pre-main-sequence population. We compare this group to the neighboring Orion OB1a and OB1b subassociations and to active star formation sites (NGC 2068/NGC 2071) within the Lynds 1630 dark cloud. We find that the 25 Ori group has a radius of 1.4◦, corresponding to 8-11 pc at the distances of Orion OB1a and OB1b. Given that the characteristic sizes of young open clusters are a few pc or less this suggests that 25 Ori is an unbound association rather than an open cluster. Due to its PMS population having a low Classical T Tauri fraction (∼10%) we conclude that the 25 Ori group is of comparable age to the 11 Myr Orion OB1a subassociation. Subject headings: open clusters and associations: individual (25 Orionis) – stars: formation – stars: late-type – stars: low-mass, brown dwarfs – stars: pre-main- sequence 1. Introduction arXiv:astro-ph/0603317v1 13 Mar 2006 The pre-main-sequence 25 Orionis group has been recently identified by the Centro de Investigaciones de Astronomia Variability Survey of Orion (CVSO; Brice˜no et al. 2005a) on the basis of multi-epoch imaging and follow-up spectroscopy. 25 Ori has also been noted by Kharchenko et al. -
Hardy 1 Williamina Fleming
Hardy 1 Williamina Fleming: Breaking Barriers with A Universe of Glass Isabella L. Hardy Junior Division Individual Performance paper 500 words In the past, women in the sciences were often overlooked, so for National History Day, I chose to focus on an under-recognized female scientist. Early in my research, I found Williamina Paton Fleming. I was surprised I had never encountered her although I had heard of her colleagues, Annie Jump Cannon and Henrietta Leavitt. I have always loved studying the stars and am fascinated by the role of women in astronomy whose important contributions are sometimes forgotten. Williamina Fleming’s unique ability to interpret astronomical photographs changed astronomy in nineteenth- century America and beyond, breaking barriers for scientists and for women. In preliminary research, I located Harvard’s digital scans of Fleming's diary and excellent period photographs, as well as many academic articles about her and other women at the Harvard Observatory. I was also privileged to interview Dr. Lindsay Smith, current Curator of Astronomical Photographs at Harvard. She was extremely helpful in suggesting sources and later reviewed the performance script. Not much is known about Fleming’s early years in Scotland. After her husband abandoned her, she worked for Harvard Observatory Director Edward Pickering, who hired her for the new project to map the night sky. The process involved taking images though telescopes, then mapping all the stars in that small section of sky. Using this process, Fleming discovered stars, novae, and nebulae and encouraged the work of other astronomers, while facilitating many important discoveries. I chose performance to give a voice to a person who has been largely unnoticed. -
Charles Le Charles Lewis Brook: Third
Charles Lewis Brook: third Director of the BAA Variable Star Section Jeremy Shears Charles Lewis Brook, MA, FRAS, FRMetS (1855−1939) served as Director of the BAA Variable Star Section from 1910 to 1921. During this time he was not interested merely in collecting the observations of the members (to which he also contributed), but he also spent considerable time analys- ing the data and preparing numerous publications on the findings. This paper discusses Brook’s life and work, with a particular focus on his con- tribution to variable star astronomy. Introduction with a particular fo- cus on his contri- bution to variable Charles Lewis Brook (1855−1939; Figures 1 and 2) was the star astronomy. It third Director of the BAA Variable Star Section (VSS) serv- draws on four sepa- ing from 1910 to 1921. As well as being an enthusiastic ob- rate obituaries: one server of variable stars, he undertook the analysis of vari- written for the BAA able star observations submitted by others, writing many by a later VSS Di- papers and memoirs on the subject. His astronomical inter- rector, W .M. Lindley (1891−1972),2 one written for the Royal ests were not confined to variables and he observed a range Astronomical Society by Annie (A. S. D.) Maunder (1868− of other astronomical objects. In addition to astronomy, he 1947),3 one for the Royal Meteorological Society4 and a brief was an active meteorologist. one published in the Huddersfield Examiner.5 In addition I Brook led a busy professional life as a Director of the have reviewed Brook’s published work, especially his pa- thread and textile company Messrs J. -
Patrick Moore's Practical Astronomy Series
Patrick Moore’s Practical Astronomy Series Other Titles in this Series Navigating the Night Sky Astronomy of the Milky Way How to Identify the Stars and The Observer’s Guide to the Constellations Southern/Northern Sky Parts 1 and 2 Guilherme de Almeida hardcover set Observing and Measuring Visual Mike Inglis Double Stars Astronomy of the Milky Way Bob Argyle (Ed.) Part 1: Observer’s Guide to the Observing Meteors, Comets, Supernovae Northern Sky and other transient Phenomena Mike Inglis Neil Bone Astronomy of the Milky Way Human Vision and The Night Sky Part 2: Observer’s Guide to the How to Improve Your Observing Skills Southern Sky Michael P. Borgia Mike Inglis How to Photograph the Moon and Planets Observing Comets with Your Digital Camera Nick James and Gerald North Tony Buick Telescopes and Techniques Practical Astrophotography An Introduction to Practical Astronomy Jeffrey R. Charles Chris Kitchin Pattern Asterisms Seeing Stars A New Way to Chart the Stars The Night Sky Through Small Telescopes John Chiravalle Chris Kitchin and Robert W. Forrest Deep Sky Observing Photo-guide to the Constellations The Astronomical Tourist A Self-Teaching Guide to Finding Your Steve R. Coe Way Around the Heavens Chris Kitchin Visual Astronomy in the Suburbs A Guide to Spectacular Viewing Solar Observing Techniques Antony Cooke Chris Kitchin Visual Astronomy Under Dark Skies How to Observe the Sun Safely A New Approach to Observing Deep Space Lee Macdonald Antony Cooke The Sun in Eclipse Real Astronomy with Small Telescopes Sir Patrick Moore and Michael Maunder Step-by-Step Activities for Discovery Transit Michael K. -
System IMF of the 25 Orionis Stellar Group Genaro Su´Arez1, Carlos Rom´An-Z´U˜Niga1, Juan Jos´Edownes2, Miguel Cervi˜No3, C´Esarbrice˜No4, Katherina Vivas4, Monika G
System IMF of the 25 Orionis Stellar Group Genaro Su´arez1, Carlos Rom´an-Z´u~niga1, Juan Jos´eDownes2, Miguel Cervi~no3, C´esarBrice~no4, Katherina Vivas4, Monika G. Petr-Gotzens5 1Instituto de Astronom´ıa,UNAM sede Ensenada, M´exico 2 Centro Universitario Regional del Este, Universidad de la Rep´ublica,Uruguay, 3Instituto de Astrof´ısicade Canarias, Tenerife, Spain, 4Cerro Tololo Interamerican Observatory, La Serena, Chile, 5European Southern Observatory, Garching bei M¨unchen, Germany Abstract We present the system IMF of the 25 Orionis stellar group complete down to the planetary-mass domain to the intermediate-mass range (10 MJup - 13.1 M ). We fitted several parameterizations to the system IMF to compare it with that in other star forming regions. We also present the advances of the follow-up spectrocopy using several world-wide facilities. We constructed the system IMF of 25 Ori subtracting Introduction to the mass distribution of the member candidates that of the contaminants from the control field and replacing the The IMF is one of the most important functions in bins where lie the giant and subgiant stars (∼ 1−3M ) by modern astrophysics because it is an essential input for the counts from the candidates after applying the distance many studies. There are a large number of IMF studies criterion (Figure 6). To the resultant 25 Ori system IMF in several stellar populations (e.g. Bastian+ 2010) but its we fitted several parameterizations (Figure 7). behavior is still under discussion, specially in the low-mass domain. Young stellar associations are useful places to study the behavior of the IMF in a wide range of mass. -
Lick Observatory Records: Photographs UA.036.Ser.07
http://oac.cdlib.org/findaid/ark:/13030/c81z4932 Online items available Lick Observatory Records: Photographs UA.036.Ser.07 Kate Dundon, Alix Norton, Maureen Carey, Christine Turk, Alex Moore University of California, Santa Cruz 2016 1156 High Street Santa Cruz 95064 [email protected] URL: http://guides.library.ucsc.edu/speccoll Lick Observatory Records: UA.036.Ser.07 1 Photographs UA.036.Ser.07 Contributing Institution: University of California, Santa Cruz Title: Lick Observatory Records: Photographs Creator: Lick Observatory Identifier/Call Number: UA.036.Ser.07 Physical Description: 101.62 Linear Feet127 boxes Date (inclusive): circa 1870-2002 Language of Material: English . https://n2t.net/ark:/38305/f19c6wg4 Conditions Governing Access Collection is open for research. Conditions Governing Use Property rights for this collection reside with the University of California. Literary rights, including copyright, are retained by the creators and their heirs. The publication or use of any work protected by copyright beyond that allowed by fair use for research or educational purposes requires written permission from the copyright owner. Responsibility for obtaining permissions, and for any use rests exclusively with the user. Preferred Citation Lick Observatory Records: Photographs. UA36 Ser.7. Special Collections and Archives, University Library, University of California, Santa Cruz. Alternative Format Available Images from this collection are available through UCSC Library Digital Collections. Historical note These photographs were produced or collected by Lick observatory staff and faculty, as well as UCSC Library personnel. Many of the early photographs of the major instruments and Observatory buildings were taken by Henry E. Matthews, who served as secretary to the Lick Trust during the planning and construction of the Observatory.