Outer Planets Assessment Group (OPAG) View of Decadal Survey
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Appendix 1: Venus Missions
Appendix 1: Venus Missions Sputnik 7 (USSR) Launch 02/04/1961 First attempted Venus atmosphere craft; upper stage failed to leave Earth orbit Venera 1 (USSR) Launch 02/12/1961 First attempted flyby; contact lost en route Mariner 1 (US) Launch 07/22/1961 Attempted flyby; launch failure Sputnik 19 (USSR) Launch 08/25/1962 Attempted flyby, stranded in Earth orbit Mariner 2 (US) Launch 08/27/1962 First successful Venus flyby Sputnik 20 (USSR) Launch 09/01/1962 Attempted flyby, upper stage failure Sputnik 21 (USSR) Launch 09/12/1962 Attempted flyby, upper stage failure Cosmos 21 (USSR) Launch 11/11/1963 Possible Venera engineering test flight or attempted flyby Venera 1964A (USSR) Launch 02/19/1964 Attempted flyby, launch failure Venera 1964B (USSR) Launch 03/01/1964 Attempted flyby, launch failure Cosmos 27 (USSR) Launch 03/27/1964 Attempted flyby, upper stage failure Zond 1 (USSR) Launch 04/02/1964 Venus flyby, contact lost May 14; flyby July 14 Venera 2 (USSR) Launch 11/12/1965 Venus flyby, contact lost en route Venera 3 (USSR) Launch 11/16/1965 Venus lander, contact lost en route, first Venus impact March 1, 1966 Cosmos 96 (USSR) Launch 11/23/1965 Possible attempted landing, craft fragmented in Earth orbit Venera 1965A (USSR) Launch 11/23/1965 Flyby attempt (launch failure) Venera 4 (USSR) Launch 06/12/1967 Successful atmospheric probe, arrived at Venus 10/18/1967 Mariner 5 (US) Launch 06/14/1967 Successful flyby 10/19/1967 Cosmos 167 (USSR) Launch 06/17/1967 Attempted atmospheric probe, stranded in Earth orbit Venera 5 (USSR) Launch 01/05/1969 Returned atmospheric data for 53 min on 05/16/1969 M. -
Comparative Saturn-Versus-Jupiter Tether Operation
Journal of Geophysical Research: Space Physics Comparative Saturn-Versus-Jupiter Tether Operation J. R. Sanmartin1 ©, J. Pelaez1 ©, and I. Carrera-Calvo1 Abstract Saturn, Uranus, and Neptune, among the four Giant Outer planets, have magnetic field B about 20 times weaker than Jupiter. This could suggest, in principle, that planetary capture and operation using tethers, which involve B effects twice, might be much less effective at Saturn, in particular, than at Jupiter. It was recently found, however, that the very high Jovian B itself strongly limits conditions for tether use, maximum captured spacecraft-to-tether mass ratio only reaching to about 3.5. Further, it is here shown that planetary parameters and low magnetic field might make tether operation at Saturn more effective than at Jupiter. Operation analysis involves electron plasma density in a limited radial range, about 1-1.5 times Saturn radius, and is weakly requiring as regards density modeling. 1. Introduction All Giant Outer planets have magnetic field B and corotating plasma, allowing nonconventional exploration. Electrodynamic tethers, which are thermodynamic (dissipative) in character, can 1. provide propellantless drag both for deorbiting spacecraft in Low Earth Orbit at end of mission and for planetary spacecraft capture and operation down the gravitational well, and 2. generate accompanying, useful electrical power, or store it to later invert tether current (Sanmartin et al., 1993; Sanmartin & Estes, 1999). At Jupiter, tethers could be effective because its field B is high (Sanmartin et al., 2008). Tethers would allow a variety of science applications (Sanchez-Torres & Sanmartin, 2011). The Saturn field is 20 times smaller, however, and tether operation involves field B twice, which makes that thermodynamic character manifest: 1. -
An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter
An Impacting Descent Probe for Europa and the other Galilean Moons of Jupiter P. Wurz1,*, D. Lasi1, N. Thomas1, D. Piazza1, A. Galli1, M. Jutzi1, S. Barabash2, M. Wieser2, W. Magnes3, H. Lammer3, U. Auster4, L.I. Gurvits5,6, and W. Hajdas7 1) Physikalisches Institut, University of Bern, Bern, Switzerland, 2) Swedish Institute of Space Physics, Kiruna, Sweden, 3) Space Research Institute, Austrian Academy of Sciences, Graz, Austria, 4) Institut f. Geophysik u. Extraterrestrische Physik, Technische Universität, Braunschweig, Germany, 5) Joint Institute for VLBI ERIC, Dwingelo, The Netherlands, 6) Department of Astrodynamics and Space Missions, Delft University of Technology, The Netherlands 7) Paul Scherrer Institute, Villigen, Switzerland. *) Corresponding author, [email protected], Tel.: +41 31 631 44 26, FAX: +41 31 631 44 05 1 Abstract We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (< 100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe’s fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. -
OPAG Update to the Planetary Science Advisory Committee (PAC)
OPAG Update to the Planetary Science Advisory Committee (PAC) ? Linda Spilker OPAG Vice-Chair, JPL PAC Meeting September 24, 2019 Large KBOs: Outer Planets Assessment Group (OPAG) Charter https://www.lpi.usra.edu/opag/ • NASA's community-based forum to provide science input for planning and prioritizing outer planet exploration activities for the next several decades • Evaluates outer solar system exploration goals, objectives, investigations and required measurements on the basis of the widest possible community outreach • Meets twice per year, summer and winter – Next meeting: Feb. 3-4, 2020, LPI, Houston, TX • OPAG documents are inputs to the Decadal Surveys • OPAG and Small Bodies Assessment Group (SBAG) have Joint custody of Pluto system and other planets among Kuiper Belt Objects KBO planets OPAG Steering Committee Jeff Moore Linda Spilker OPAG Chair OPAG Vice-Chair * =New Member Ames Research Center Jet Propulsion Lab Alfred McEwen Lynnae Quick* Kathleen Mandt* University of Arizona NASA Goddard Applied Physics Laboratory OPAG Steering Committee Scott Edgington Amanda Hendrix Mark Hofstadter Jet Propulsion Lab Planetary Science Institute Jet Propulsion Lab Terry Hurford Carol Paty Goddard Space Flight Center Georgia Institute of Technology OPAG Steering Committee Morgan Cable* Britney Schmidt Kunio Sayanagi Jet Propulsion Lab Georgia Institute of Technology Hampton University * =New Member Tom Spilker* Abigail Rymer* Consultant Applied Physics Lab Recent and Upcoming OPAG-related Meetings • OPAG Subsurface Needs for Ocean Worlds -
(Preprint) AAS 18-416 PRELIMINARY INTERPLANETARY MISSION
(Preprint) AAS 18-416 PRELIMINARY INTERPLANETARY MISSION DESIGN AND NAVIGATION FOR THE DRAGONFLY NEW FRONTIERS MISSION CONCEPT Christopher J. Scott,∗ Martin T. Ozimek,∗ Douglas S. Adams,y Ralph D. Lorenz,z Shyam Bhaskaran,x Rodica Ionasescu,{ Mark Jesick,{ and Frank E. Laipert{ Dragonfly is one of two mission concepts selected in December 2017 to advance into Phase A of NASA’s New Frontiers competition. Dragonfly would address the Ocean Worlds mis- sion theme by investigating Titan’s habitability and prebiotic chemistry and searching for evidence of chemical biosignatures of past (or extant) life. A rotorcraft lander, Dragonfly would capitalize on Titan’s dense atmosphere to enable mobility and sample materials from a variety of geologic settings. This paper describes Dragonfly’s baseline mission design giv- ing a complete picture of the inherent tradespace and outlines the design process from launch to atmospheric entry. INTRODUCTION Hosting the moons Titan and Enceladus, the Saturnian system contains at least two unique destinations that have been classified as ocean worlds. Titan, the second largest moon in the solar system behind Ganymede and the only planetary satellite with a significant atmosphere, is larger than the planet Mercury at 5,150 km (3,200 miles) in diameter. Its atmosphere, approximately 10 times the column mass of Earth’s, is composed of 95% nitrogen, 5% methane, 0.1% hydrogen along with trace amounts of organics.1 Titan’s atmosphere may resemble that of the Earth before biological processes began modifying its composition. Similar to the hydrological cycle on Earth, Titan’s methane evaporates into clouds, rains, and flows over the surface to fill lakes and seas, and subsequently evaporates back into the atmosphere. -