![]() 2010 Todorović 2018).ĭespite these numerous studies, the true nature of Phaethon has not yet been convincingly revealed. 2004), or to the dynamical link with the main-belt asteroid (2) Pallas ( de León et al. 2018), to the associated Geminid meteor stream ( Gustafson 1989 Williams & Wu 1993 Trigo-Rodríguez et al. Other studies were dedicated to Phaethon’s comet-like activity ( Jewitt & Li 2010 Jewitt et al. 2018), have so far been inferred from a wide range of datasets: photometry in optical ( Krugly et al. Physical properties of the low-perihelion near-Earth asteroid Phaethon, target of the proposed JAXA DESTINY + mission ( Arai et al. Key words: minor planets / asteroids: individual: (3200) Phaethon / methods: numerical / methods: observational / astrometry / celestial mechanics These findings render a cometary origin unlikely for Phaethon. Phaethon’s bulk density is consistent with typical values for large (> 100 km) C-complex asteroids and supports its association with asteroid (2) Pallas, as first suggested by dynamical modeling. We further investigated the suggestion that Phaethon may be in a cluster with asteroids (155140) 2005 UD and (225416) 1999 YC that was formed by rotational fission of a critically spinning parent body.Ĭonclusions. If the size is slightly larger ∼5.7 − 5.8 km, as suggested by radar data, the bulk density would decrease to 1.48 ± 0.42 g cm −3. With the derived volume-equivalent size of 5.1 km, the bulk density is 1.67 ± 0.47 g cm −3. The orbit analysis reveals a secular drift of the semimajor axis of −(6.9 ± 1.9)×10 −4 au Myr −1. The characteristic size of the regolith grains is 1 − 2 cm. Phaethon has a top-like shape with possible north-south asymmetry. We obtained a unique solution for Phaethon’s pole orientation at (318 ° , − 47 ° ) ecliptic longitude and latitude (both with an uncertainty of 5°), and confirm the previously reported thermophysical properties ( D = 5.1 ± 0.2 km, Γ = 600 ± 200J m −2 s −0.5 K −1). We used the convex inversion model to derive the spin orientation and 3D shape model of Phaethon, and a detailed numerical approach for an accurate analysis of the Yarkovsky effect. This constraint allowed us to estimate the bulk density by assuming that the drift is dominated by the Yarkovsky effect. We also used the available astrometric observations of Phaethon, including those obtained by the Arecibo radar and the Gaia spacecraft, to constrain the secular drift of the orbital semimajor axis. We used the newly obtained optical light curves to improve the spin and shape model of Phaethon and to determine its surface physical properties derived by thermophysical modeling. The recent close approach of the near-Earth asteroid (3200) Phaethon offered a rare opportunity to obtain high-quality observational data of various types.Īims. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USAĭepartment of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 0076100, IsraelĪstronomical Institute, Academy of Sciences of the Czech Republic,įričova 1, 25165 Ondřejov, Czech RepublicĬenter for Solar System Studies, 11355 Mount Johnson Court, Rancho Cucamonga, CA 91737, USAĬenter for Solar System Studies, 446 Sycamore Ave., Eaton, CO 80615, USAĬontext. Institute of Astronomy, Charles University, Prague, V Holešovičkách 2, 18000 Prague 8, Czech RepublicĮ-mail: Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, France Astronomical objects: linking to databases.Including author names using non-Roman alphabets.Suggested resources for more tips on language editing in the sciences Punctuation and style concerns regarding equations, figures, tables, and footnotes Lofty valuations and the "amateur aspect of the market with Robinhood" will fuel volatility, he said. ![]() Moreover, the investor predicted the VIX - an index known as the market's "fear gauge" because it measures investors' volatility expectations - will surge past 100 for the first time when the crash comes. He expects year-on-year inflation of over 3% in June or July, the dollar to weaken in the coming months, and gold prices to bounce back. Gundlach made several calls during the webcast. For example, he pointed to rising trade and budget deficits, depressed consumer confidence, record readings on the " Buffett indicator" and other market gauges, heady price-earnings ratios, and the disconnect between growth, employment, and the stock market. The DoubleLine boss deployed a wealth of economic data to make his arguments. "We're pretty clearly in a speculative bubble regarding debt and government activity," he said. Gundlach also issued a stark warning about federal spending during the pandemic. ![]()
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