Forming the Flora Family: Implications for the Near-Earth Asteroid Population and Large Terrestrial Planet Impactors David Vokrouhlický1, William F. Bottke2, and David Nesvorný2 1 Institute of Astronomy, Charles University, V Holešovičkách 2, CZ–18000 Prague 8, Czech Republic; vokrouhl@cesnet.cz 2 Department of Space Studies, Southwest Research Institute, … Indeed, they are generally nearly constant on a 10 7 -10 ⁸-year time scale. Analysis of the rock suggests it was apparently exposed to cosmic rays for only about 1.2 million years, unusually short for rocks originating in the Flora family. [4] This gives an axial tilt of 78°, plus or minus ten degrees. There is also a scattered group of objects in the general vicinity of the Vesta family but not part of it. [11][12], On 26 July 2013, Flora at magnitude 8.8 occulted the star 2UCAC 22807162 over parts of South America, Africa, and Asia.[13]. We created an initial Flora family and followed test asteroids 1 and 3 km in diameter using a numerical code that accounted for both planetary perturbations and nongravitational effects. 2007, Nature, 449, 48-53). In many or most cases the parent body was shattered, but there are also several families which resulted from a large cratering event which did not disrupt the parent body (e.g. These include: 809 Lundia — Orbits within the Flora family region; 956 Elisa; 1459 Magnya — Orbits in the outer asteroid belt, too far from Vesta to be genetically related. It is located in the inner region of the asteroid belt. Formed from a catastrophic collision of a parent body larger than 150 km in diameter, the Flora family is located in the innermost part of the main belt near the {ν } 6 secular resonance. This splitting The family name is based on the name or provisional designation of the largest member of the family. Asteroid Flora. 8 Flora is a big, bright, main belt asteroid.It is the closest big asteroid: no asteroid closer to the Sun has a diameter above 25 kilometres or two-elevenths that of Flora itself, and not until the tiny 149 Medusa was found was a single asteroid orbiting at a closer mean distance known. This means that it is probably a piece from an asteroid collision that occurred roughly 200 million years ago. The influence of the Yarkovsky and YORP effects should be observable among objects in asteroid families, especially in the Flora family, which lies close to the Sun and consists of many small objects. Flora family – A prominent family of stony asteroids with an albedo of 0.24. It accounts for 15–20% of the main belt as- teroids with 2.1< a <2.5 AU. Flora (minor planet designation: 8 Flora) is a large, bright main-belt asteroid. Such cratering families typically consist of a single large body and a swarm of asteroids that are many times smaller. In extreme cases such as the Flora family, the degree of dispersion and the presence of a … Because of its poorly defined edges, and the location of Flora itself near the edge, this asteroid group has also sometimes been called the Ariadne family, when Flora did not make it into the group during an analysis (e.g. They are nowadays identified as clusters in the proper orbital elements space. Differences in these orbital and physical properties suggest that the creation of the Flora family was more … Especially, the orbit and spin characteristics can reflect the influences of the Yarkovsky effect and the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect on the evolution of the asteroid family, respectively. The largest asteroid to be a true member of a family (as opposed to an interloper in the case of Ceres with the Gefion family) is 4 Vesta. Flora Asteroids: 951 Gaspra, 8 Flora, Flora Family, 43 Ariadne, 9913 Humperdinck, 291 Alice, (9928) 1981 We9, 4065 Meinel, 281 Lucretia: Books, LLC, Books, LLC: Amazon.nl The Flora family of asteroids is a large grouping of S-type asteroids in the inner main belt, whose origin and properties are relatively poorly understood at present.Roughly 4-5% of all main belt asteroids belong to this family. Asteroid 8 Flora will be well placed, lying in the constellation Cetus, well above the horizon for much of the night.. In recent years, the distribution of orbital elements within an asteroid family has been shown to be affected both by the Yarkovsky effect and by passage across weak planetary resonances (e.g., Nesvorny et al. Flora asteroid family: Number of members ~ 819, Largest member: 8 Flora, 136km, Average distance from Sun: 2.169 -2.211 AU's. Its location in the inner main belt makes their members available for photometric and spec-troscopic observations even for small telescopes. The Flora family is one of the asteroid families that were discovered early (Hirayama, 1918). the Flora family) have complex intern… Jenniskens calculated the Chelyabinsk object may have come from the Flora asteroid family in the inner asteroid belt. Flora (minor planet designation: 8 Flora) is a large, bright main-belt asteroid.It is the innermost large asteroid: no asteroid closer to the Sun has a diameter above 25 kilometres or two-elevenths that of Flora itself, and not until the tiny 149 Medusa was discovered was a single asteroid orbiting at a closer mean distance known. The Flora family, being located near the inner edge of the main asteroid belt, is one of the largest asteroid families in … Many S-type asteroids have similar compositions and spectral characteristics with certain meteorites. Planetoïdenfamilie - Asteroid family. Regardless of your location on the Earth, 8 Flora will reach its highest point in the sky around midnight local time. Though di use, the family associated with asteroid (8) Flora dominates the inner main belt in terms of the extent of its members in orbital parameter space, result- … The family of asteroids Flora Licence Public domain Public domain false false: I, the copyright holder of this work, release this work into the public domain. The largest among them is associated with (8) Flora. At 81.7 million miles (131.4 million km) away, it's almost 21 times closer and completes an orbit in 3.3 years compared to the ice giant's 84 years. Flora family The Flora family of asteroids is a big group of S-type asteroids in the closer part of the main belt , whose origin and properties are not well understood right now. This is a shape model of Flora computed using light curve inversion techniques. Stervormig families zichtbaar als afzonderlijke concentraties bij asteroïden uitgezet in de juiste baanelement ruimte ( … The Flora family of asteroids is a large grouping of S-type asteroids in the inner main belt, whose origin and properties are relatively poorly understood at present.Roughly 4-5% of all main belt asteroids belong to this family. Lightcurve analysis indicates that Flora's pole points towards ecliptic coordinates (β, λ) = (16°, 160°) with a 10° uncertainty. The Flora family of asteroids is a big group of S-type asteroids in the closer part of the main belt, whose origin and properties are not well understood right now. It is the seventh-brightest asteroid with a mean … We discuss the possibility that the parent bodies of the Flora family and of the ordinary L … The Flora family, one of the largest with more than 800 known members, may have formed from a collision less than a billion years ago. [citation needed]A large proportion have orbital elements similar to those of 4 Vesta, either close enough to be part of the Vesta family, or having similar eccentricities and inclinations but with … Ingrid is a member of the Flora family , a giant asteroid family and the largest family of stony asteroids. The distribution of proper elements and physical properties of Flora-family asteroids are compared with those of families believed to have formed from the catastrophic disruption of parent bodies. Forming the Flora Family: Implications for the Near-Earth Asteroid Population and Large Terrestrial Planet Impactors 2017, AJ, 153 , 172 Vokrouhlicky, D., and 12 colleagues: Because of its poorly defined boundaries, and the location of Flora itself near the edge, this asteroid group has also sometimes been called the Ariadne family, … In the 1968 science-fiction film The Green Slime, an orbital perturbation propels the asteroid Flora into a collision course with Earth. [citation needed]. Evidence is presented indicating that the Flora family is of common origin. Earlier work by Bill Bottke, a planetary scientist at the Southwest Research Institute, has fingered one such asteroid family as the birthplace of the dinosaur-killer and accused another, the Flora family, of causing impacts on Earth perhaps a billion years ago. For one thing, it's in an orbit shared by the Flora family of asteroids, which formed roughly 200 million years ago, so it's likely just a chip off this grouping's parent body. Asteroid families are believed to originate by catastrophic disruptions of large asteroids. Our results suggest that the Flora family dynamically disperses on a few 10 8 -year time scale and that its age may be significantly less than 10 9 years. 2007, Nature, 449, 48-53). Several new studies on the Feb. 15 meteor explosion over Chelyabinsk, Russia, has revealed a much higher asteroid risk to Earth than previously thought, scientists say. the Vesta, Pallas, Hygiea, and Massalia families). 1), a little narrower than the values adopted by the other studies.Considered that other asteroid families may exist around the region where the Flora family resides, in the condition that a sufficient number of sample members … 8 Flora is a big, bright, main belt asteroid.It is the closest big asteroid: no asteroid closer to the Sun has a diameter above 25 kilometres or two-elevenths that of Flora itself, and not until the tiny 149 Medusa was found was a single asteroid orbiting at a closer mean distance known. It is the seventh brightest asteroid with a mean opposition magnitude of +8.7. About 4-5% of all main belt asteroids belong to this family. Asteroid families are the remnants of the catastrophic collision, and their fundamental physical properties provide us the information of their parent bodies and evolutions. Jenniskens speculates the Chelyabinsk rock belonged to a larger "rubble pile" asteroid that broke apart 1.2 million years ago, possibly after a close encounter with Earth's gravitational pull. It orbits the Sun in the inner main-belt at a distance of 1.8–2.7 AU once every 3 years and 5 months (1,237 days). Because of its poorly defined boundaries, and the location of Flora itself near the edge, this asteroid group has also sometimes been called the Ariadne family, … The proper elements are analytically defined as constants of motion of a suitably simplified dynamical system. The dynamical and physical properties of the Flora family are described in Section 2. The members of the families are thought to be fragments of past asteroid collisions. 402 8 Flora It is 2.3 times farther from … This is because unrelated asteroids are hard to distinguish from family members because the family is of the same spectral type (S) that dominates the closer main belt overall. [7] It is the seventh-brightest asteroid with a mean opposition magnitude of +8.7. The Flora asteroid family, which resides in the innermost region of the main asteroid belt, has been known for nearly a century. It is a remnant from a collisional disruption of a large body or bodies that occurred hundreds of My to a few Gy ago (the age of the family was approximated by several authors, for example 2156 Kate, identified by one of the clustering method and dif- Three additional, already known spin vectors for 951 Gaspra ferent than S taxonomic type, which are probable interlopers in (all determinations collected at the Poznan Observatory web- the Flora family, were also excluded, because asteroid families site, Kryszczynska et al. [citation needed], The name Flora was proposed by John Herschel, from Flora, the Latin goddess of flowers and gardens, wife of Zephyrus (the personification of the West wind), and mother of Spring. Methods. add example. The Flora family of asteroids is a big group of S-type asteroids in the closer part of the main belt, whose origin and properties are not well understood right now.About 4-5% of all main belt asteroids belong to this family. Asteroid 8 Flora is currently in the constellation of Cetus.The current Right Ascension of Asteroid 8 Flora is 02h 39m 46s and the Declination is +10° 16’ 14” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom []).The current magnitude of Asteroid 8 Flora is 9.79 (JPL). Whoa — that's a lot of relatives! [10] This meteorite type comprises about 38% of all meteorites impacting the Earth. Curiously, our understanding of its properties has remained fairly murky even as our knowledge of the asteroid belt has increased. 1998, and also by inspection of the PDS asteroid taxonomy data set for non S-type members.) All the members of the Flora family probably came from the breakup of a single parent body; however, other asteroids in this region with similar orbital characteristics appear to have different origins. PRELIMINARIES ON THE FLORA FAMILY The inner zone of the asteroid belt is characterized by the presence of three populous clans (named Flora, Nysa, and Vesta in Zappal`aet al.1994). This makes sense because it's the largest member of the Flora family, a group of more than 13,000 asteroids that share similar orbits. [11] This mistake was uncovered only in 1995. Aims. The few unrelated asteroids that have been found are all small (Florczak et al. Our Flora family members reproduce the observed semimajor axis, eccentricity, and inclination distributions of the real family after to 1.4 Gyr. Formally known as 1979 MB4, this is a 2km-wide asteroid of the Flora family in the asteroid belt’s inner region. See the latest details. Flora was discovered in 1847 and named for the Latin goddess of gardens and flowers. An asteroid family is a group of minor planets that share similar orbital elements, such as semimajor axis, eccentricity, and orbital inclination. Less than a dozen degrees southeast of Uranus, you'll find the main belt asteroid 8 Flora. Curiously, our understanding of its properties has remained fairly murky even as our knowledge of the asteroid belt has increased. Available evidence concerning the Flora family, together with recent models for the collisional evolution of the asteroids, suggests that this family may have originated from a binary or multiple asteroid. Flora can reach a magnitude of +7.9 at a favorable opposition near perihelion es Estas concentraciones son las familias de asteroides. In recent years, the distribution of orbital elements within an asteroid family has been shown to be affected both by the Yarkovsky effect and by passage across weak planetary resonances (e.g., Nesvorny et al. It was his second asteroid discovery after 7 Iris. Objects in this region, when pushed onto planet-crossing orbits, tend to have relatively high probabilities of striking the Earth. NESVORNY SYNTHETIC FAMILY NAME * The name of the asteroid family in the Nesvorny family analysis based on synthetic proper elements. Asteroids are given minor planet numbers, but not all minor planets are asteroids. From Simple English Wikipedia, the free encyclopedia, Asteroid Families: Search of a 12,487-Asteroid Sample Using Two Different Clustering Techniques, https://simple.wikipedia.org/w/index.php?title=Flora_family&oldid=7289192, Articles with unsourced statements from February 2007, Creative Commons Attribution/Share-Alike License. Flora's the largest, inner main belt asteroid with a diameter of about 91 miles (147 km) or about the size of Connecticut. Our Flora family members reproduce the observed semimajor axis, eccentricity, and inclination distributions of the real family after to 1.4 Gyr. These factors suggest that Flora may be a primary source of … It is a remnant from a collisional disruption of a large body or bodies that occurred hundreds of My to a few Gy ago (the age of the family was approximated by several authors, for example Though di use, the family associated with asteroid (8) Flora dominates the inner main belt in terms of the extent of its members in orbital parameter space, result- … Neujmin named it after Gaspra, a Black Sea retreat that was visited by his contemporaries, such as Gorky and Tolstoy.. Gaspra was the first asteroid ever to be closely approached when it was visited … Because of the high background density of asteroids in this part of space, one might expect that a great number of asteroids unrelated to the collision that made the family would be present. The Flora family asteroids … In 1918, the Japanese astronomer K. Hirayama first recognized some non random concentrations of asteroid elements. Some families (e.g. Flora (minor planet designation: 8 Flora) is a large, bright main-belt asteroid. She distinguished prograde and retrograde groups of as-teroidsandreportedan excessofprograderotators. The Flora Family Foundation was established in 1998 by the family of William R. Hewlett (co-founder of the Hewlett-Packard Company) and his wife Flora Lamson Hewlett. In extreme cases such as the Flora family, the degree of dispersion and the presence of a significant … Contents[show] General properties Large, prominent families contain several hundred recognized asteroids (and many more smaller objects which … Nevertheless, the parent body was almost for sure destroyed by the impact/s that made the family, and Flora is probably a gravitational aggregate of most of the pieces.[source?] Example sentences with "asteroid family", translation memory. The Flora asteroid family, which resides in the innermost region of the main asteroid belt, has been known for nearly a century. The Flora family is a collection of asteroids near the inner edge of the asteroid belt whose orbits have semimajor axes of 2.12 to 2.25 AU and mean inclinations of about 5°. WikiMatrix. Request PDF | On Jan 1, 2008, A. Kryszczynska and others published Physical Investigations of the Flora Family Asteroids | Find, read and cite all the research you need on ResearchGate Flora is the parent body of the Flora family of asteroids, and by far the largest member, comprising about 80% of the total mass of this family. About 4-5% of all main belt asteroids belong to this family. It is the innermost large asteroid: no asteroid closer to the Sun has a diameter above 25 kilometres or two-elevenths that of Flora itself, and not until the tiny 149 Medusa was discovered was a single asteroid orbiting at a closer mean distance known. Minor planet numbers are also given to objects of the Kuiper belt, which is similar to the asteroid belt but farther out around 30–60 AU, whereas asteroids are mostly between 2–3 AU from the Sun and at the orbit of Jupiter 5 AU from the Sun. It is the seventh-brightest asteroid with a mean opposition magnitude of +8.7. Flora, and the whole Flora family generally, are good candidates for being the parent bodies of the L chondrite meteorites. Van Wikipedia, de gratis encyclopedie. Again, one of the largest families with more than 13.000 members, or about 3.5% of all main-belt asteroids. This applies worldwide. [citation needed]. During an observation on 25 March 1917, 8 Flora was mistaken for the 15th-magnitude star TU Leonis, which led to that star's classification as a U Geminorum cataclysmic variable star. Asteroid 8 Flora. The Flora asteroid family members defined by the LCDB are distributed in the semi-major axis interval of a ∈ [2.15, 2.35] au (as shown in Fig. en These concentrations are the asteroid families. Flora's the largest, inner main belt asteroid with a diameter of about 91 miles (147 km) or about the size of Connecticut. From Redmond, it will be visible between 20:02 and 04:07.It will become accessible around 20:02, when it rises to an altitude of 21° above your eastern … 2002, Icarus, 157, 155-172; Bottke et al. Formed from a catastrophic collision of a parent body larger than 150 km in diameter, the Flora family is located in the innermost part of the main belt near the {ν } 6 secular resonance. It's about 147 kilometers across — comparable in size to the state of Connecticut — and the largest asteroid in the inner main belt. Tend to have relatively high probabilities of striking the Earth, 8 Flora ) is a mixture silicate! 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