Related Research Articles
The giant-impact hypothesis, sometimes called the Big Splash, or the Theia Impact, is an astrogeology hypothesis for the formation of the Moon first proposed in 1946 by Canadian geologist Reginald Daly. The hypothesis suggests that the Early Earth collided with a Mars-sized dwarf planet of the same orbit approximately 4.5 billion years ago in the early Hadean eon, and the ejecta of the impact event later accreted to form the Moon. The impactor planet is sometimes called Theia, named after the mythical Greek Titan who was the mother of Selene, the goddess of the Moon.
Phobos is the innermost and larger of the two natural satellites of Mars, the other being Deimos. The two moons were discovered in 1877 by American astronomer Asaph Hall. It is named after Phobos, the Greek god of fear and panic, who is the son of Ares (Mars) and twin brother of Deimos.
Planetary geology, alternatively known as astrogeology or exogeology, is a planetary science discipline concerned with the geology of celestial bodies such as planets and their moons, asteroids, comets, and meteorites. Although the geo- prefix typically indicates topics of or relating to Earth, planetary geology is named as such for historical and convenience reasons; due to the types of investigations involved, it is closely linked with Earth-based geology. These investigations are centered around the composition, structure, processes, and history of a celestial body.
Planet V is a hypothetical fifth terrestrial planet posited by NASA scientists John Chambers and Jack J. Lissauer to have once existed between Mars and the asteroid belt. In their hypothesis the Late Heavy Bombardment of the Hadean era began after perturbations from the other terrestrial planets caused Planet V's orbit to cross into the asteroid belt. Chambers and Lissauer presented the results of initial tests of this hypothesis during the 33rd Lunar and Planetary Science Conference, held from March 11 through 15, 2002.
Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, all of which were formed by impacts. The International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated.
Paul D. Spudis (1952–2018) was an American geologist and lunar scientist. His specialty was the study of volcanism and impact processes on the planets, including Mercury and Mars.
George Wetherill was a physicist and geologist and the director emeritus of the department of terrestrial magnetism at the Carnegie Institution of Washington, DC, US.
The Lunar and Planetary Institute (LPI) is a scientific research institute dedicated to study of the solar system, its formation, evolution, and current state. The Institute is part of the Universities Space Research Association (USRA) and is supported by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). Located at 3600 Bay Area Boulevard in Houston, Texas, the LPI is an intellectual leader in lunar and planetary science. The Institute serves as a scientific forum attracting world-class visiting scientists, postdoctoral fellows, students, and resident experts; supports and serves the research community through newsletters, meetings, and other activities; collects and disseminates planetary data while facilitating the community's access to NASA astromaterials samples and facilities; engages and excites the public about space science; and invests in the development of future generations of scientists. The LPI sponsors and organizes several workshops and conferences throughout the year, including the Lunar and Planetary Science Conference (LPSC) held in March in the Houston area.
The interplanetary dust cloud, or zodiacal cloud, consists of cosmic dust that pervades the space between planets within planetary systems, such as the Solar System. This system of particles has been studied for many years in order to understand its nature, origin, and relationship to larger bodies. There are several methods to obtain space dust measurement.
A sample-return mission is a spacecraft mission to collect and return samples from an extraterrestrial location to Earth for analysis. Sample-return missions may bring back merely atoms and molecules or a deposit of complex compounds such as loose material and rocks. These samples may be obtained in a number of ways, such as soil and rock excavation or a collector array used for capturing particles of solar wind or cometary debris. Nonetheless, concerns have been raised that the return of such samples to planet Earth may endanger Earth itself.
Tooting is an impact crater with volcanic features at 23.1°N, 207.1°E, in Amazonis Planitia, due west of the volcano Olympus Mons, on Mars. It was identified by planetary geologist Peter Mouginis-Mark in September 2004. Scientists estimate that its age is on the order of hundreds of thousands of years, which is relatively young for a Martian crater. A later study confirms this order of magnitude estimate. A preliminary paper describing the geology and geometry of Tooting was published in 2007 by the journal Meteoritics and Planetary Science, vol. 42, pages 1615–1625. Further papers have been published, including a 2010 analysis of flows on the walls of Tooting crater by A. R. Morris et al., and a 2012 review paper by P.J. Mouginis-Mark and J.M. Boyce in Chemie der Erde Geochemistry, vol. 72, p. 1–23. A geologic map has also been submitted in 2012 to the U.S. Geological Survey for consideration and future publication.
The Mars trojans are a group of trojan objects that share the orbit of the planet Mars around the Sun. They can be found around the two Lagrangian points 60° ahead of and behind Mars. The origin of the Mars trojans is not well understood. One theory suggests that they were primordial objects left over from the formation of Mars that were captured in its Lagrangian points as the Solar System was forming. However, spectral studies of the Mars trojans indicate this may not be the case. Another explanation involves asteroids chaotically wandering into the Mars Lagrangian points later in the Solar System's formation. This is also questionable considering the short dynamical lifetimes of these objects. The spectra of Eureka and two other Mars trojans indicates an olivine-rich composition. Since olivine-rich objects are rare in the asteroid belt it has been suggested that some of the Mars trojans are captured debris from a large orbit-altering impact on Mars when it encountered a planetary embryo.
The history of scientific thought about the formation and evolution of the Solar System began with the Copernican Revolution. The first recorded use of the term "Solar System" dates from 1704. Since the seventeenth century, philosophers and scientists have been forming hypotheses concerning the origins of our Solar System and the Moon and attempting to predict how the Solar System would change in the future. René Descartes was the first to hypothesize on the beginning of the Solar System; however, more scientists joined the discussion in the eighteenth century, forming the groundwork for later hypotheses on the topic. Later, particularly in the twentieth century, a variety of hypotheses began to build up, including the now-commonly accepted nebular hypothesis.
The Solar System Exploration Research Virtual Institute (SSERVI), originally the NASA Lunar Science Institute, is an organization, established by NASA in 2008, that supplemented and extended existing NASA lunar science programs. Supported by the NASA Science Mission Directorate (SMD) and the Exploration Systems Mission Directorate (ESMD), SSERVI is a NASA program office located at the NASA Ames Research Center and was modeled on the NASA Astrobiology Institute (NAI) with dispersed teams across the nation working together to help lead the agency's research activities related to NASA's human exploration goals. Competitively selected team investigations focused on one or more aspects of lunar science investigations of the Moon, from the Moon, and on the Moon.
The Late Heavy Bombardment (LHB), or lunar cataclysm, is a hypothesized astronomical event thought to have occurred approximately 4.1 to 3.8 billion years (Ga) ago, at a time corresponding to the Neohadean and Eoarchean eras on Earth. According to the hypothesis, during this interval, a disproportionately large number of asteroids and comets collided into the terrestrial planets and their natural satellites of the inner Solar System, including Mercury, Venus, Earth and Mars. These came from both post-accretion and planetary instability-driven populations of impactors. Although it used to be widely accepted, it remained difficult to provide an overwhelming amount of evidence for the hypothesis. However, recent re-appraisal of the cosmo-chemical constraints indicates that there was likely no late spike in the bombardment rate.
The five-planet Nice model is a numerical model of the early Solar System that is a revised variation of the Nice model. It begins with five giant planets, the four that exist today plus an additional ice giant between Saturn and Uranus in a chain of mean-motion resonances.
Planetary science is the scientific study of planets, celestial bodies and planetary systems and the processes of their formation. It studies objects ranging in size from micrometeoroids to gas giants, aiming to determine their composition, dynamics, formation, interrelations and history. It is a strongly interdisciplinary field, which originally grew from astronomy and Earth science, and now incorporates many disciplines, including planetary geology, cosmochemistry, atmospheric science, physics, oceanography, hydrology, theoretical planetary science, glaciology, and exoplanetology. Allied disciplines include space physics, when concerned with the effects of the Sun on the bodies of the Solar System, and astrobiology.
Ian Andrew Crawford is a British professor of planetary science and astrobiology at Birkbeck, University of London in the United Kingdom.
References
- 1 2 "7807 Grier (1975 SJ1)", JPL Small-Body Database , Jet Propulsion Laboratory, SPK-ID: 20007807
- 1 2 "Dr. JA Grier", Staff profiles, Planetary Science Institute, retrieved 2024-02-02; see also linked professional history
- ↑ Grier, J. A. (1999), Determining the ages of impact events: Multidisciplinary studies using remote sensing and sample analysis techniques (Doctoral dissertation), University of Arizona, p. 891, Bibcode:1999PhDT........22G, hdl:10150/284058
- ↑ Resnick, Andrew (2020), "Review of Airless Bodies of the Inner Solar System", Contemporary Physics, 61 (1): 52–53, Bibcode:2020ConPh..61...52R, doi:10.1080/00107514.2020.1736166
- ↑ AAS Names 21 New Fellows for 2024, American Astronomical Society, February 1, 2024, retrieved 2024-02-02
- ↑ "JA Grier", 500 queer scientists, retrieved 2024-02-02
- 1 2 Grier, JA, "Writer Bio", One Writer's Mind, retrieved 2024-02-02
- ↑ "Interview with Bryce Ellicott, Part 1", Living poetry, April 11, 2011; "Interview with Bryce Ellicott, Part 2", Living poetry, April 25, 2011
