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The Origin of the Elements and Earth
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Astronomers define planets as being massive enough to be rounded by their own gravity but not massive enough to heat their cores to temperatures required for nucleosynthesis. Additionally, planets have sufficient gravity to attract all planetesimals and other debris from the regions around them. A dwarf planet, also called a planetoid, meets the first two-thirds of this definition but has insufficient gravity to clear the area around it of other space debris (Fig. 1.16). Pluto, discovered in 1930, was originally classified as a planet but now has been downgraded to dwarf planet status. The known and named dwarf planets, in increasing size, are Ceres, Makemake, Haumea, Eris, and Pluto. Ceres is the largest body of the Asteroid Belt but is the smallest dwarf planet with a diameter of about 945 kilometers (590 miles). Pluto (2370 kilometers diameter) and Eris (2330 kilometers diameter) are the largest dwarf planets. Some dwarf planets have moons; Pluto has Charon and four other moons. Most of the dwarf planets are much icier than Ceres because Ceres is in the Asteroid Belt (closer to the sun) and the other four dwarf planets are outside the orbit of Neptune. Astronomers will likely discover other dwarf planets in the outermost solar system in the future.
Usefulness and Limits of Predictive Relationships
Published in A. K. Haghi, Devrim Balköse, Omari V. Mukbaniani, Andrew G. Mercader, Applied Chemistry and Chemical Engineering, 2017
Emili Besalu, Lionello Pogliani, J. Vicente Julian-Ortiz
The dwarf planet Ceres (in italics) has been discovered thanks to the Titius–Bode rule of eq 2.4 in 1801 by the Italian astronomer Giuseppe Piazzi. It is the biggest body in the asteroid belt between Mars and Jupiter, making a third of the mass of the belt. Actually, the then newly proposed Titius–Bode rule was first brilliantly confirmed by the discovery of Uranus in 1781 by William Herschel. The high quality of the prediction is confirmed by the very good Q2 vale for N = 8 (eq 2.4). Ceres and Uranus are the only two predictions of the rule as it fails to predict Neptune’s orbit (29% error), and even more Pluto’s orbit (96% error). Failure becomes enormous with the recently discovered dwarf planets: Haumea, discovered in 2004, with semimajor axis at 43.13 AU, is predicted at 154 AU with a 257% error. Makemake, discovered in 2005, with semimajor axis at 45.79 AU is predicted at 307.6 AU with a 572% error. Finally, Eris, discovered also in 2005, with semimajor axis at 68.01 AU is predicted at 614.8 AU with an 804% error. In fact, eq 2.9 shows how things get consistently worse (especially at the predictive leave-one-out Q2 level) when we try to ft the 13 planets, dTB=10.3(±3.7)+0.03(±0.006)k,wherek=2m,withm=-∞,0,1,2,3,...N=13all bodies,Q2=0.46,r2=0.749,s=12,F=33 $$ \begin{gathered} d_{{{\text{TB}}}} = 10.3( \pm 3.7) + 0.03( \pm 0.006)k,\,\,{\text{where}}\,k = 2^{{\text{m}}} , \hfill \\ {\text{with}}\,{\text{m}} = - \infty ,\,0,1,2,3,\,... \hfill \\ N = 13\,\left( {{\text{all bodies}}} \right),\,Q^{2} = 0.46,\,\,r^{2} = 0.749,\,\,s = 12,{\kern 1pt} \,F = 33 \hfill \\ \end{gathered} $$
A review and comparison of surface incident shortwave radiation from multiple data sources: satellite retrievals, reanalysis data and GCM simulations
Published in International Journal of Digital Earth, 2023
Shuyue Yang, Xiaotong Zhang, Shikang Guan, Wenbo Zhao, Yanjun Duan, Yunjun Yao, Kun Jia, Bo Jiang
Figure 6 depicts the box plots of annual mean Rs of seven products during the period of 2001–2010, and the detailed values over globe, land and ocean are summarized in Table 4. As seen, the annual mean Rs of GLASS was the lowest over the globe, land and ocean, with values of 177.1, 179.3 and 175.5 W/m2, respectively. The CFSR displayed the highest mean Rs, which is 191.3 and 191.5 W/m2 in globe and ocean, while MERRA2 was the highest of 196.0 W/m2 in land. The maximum, minimum and mean Rs estimates over land of most of the products tended to be higher than those over ocean, except for the CERES-EBAF and CFSR. For ERA5, CERES-EBAF and CMIP6 GCMs, the maximum and minimum values of Rs were close, which means that the differences in annual mean Rs of these products were minor.
Remote sensing of earth’s energy budget: synthesis and review
Published in International Journal of Digital Earth, 2019
Shunlin Liang, Dongdong Wang, Tao He, Yunyue Yu
In contrast to the land surface albedo products, there are few ocean surface albedo products from satellite data. The most complete product is the clouds, albedo and radiation (CLARA) product (Karlsson et al. 2017; Riihela et al. 2013). The GEWEX and CERES products can be used to calculate ocean albedo. The GLASS ocean albedo product from MODIS and AVHRR data is still under development (Feng, Liu, et al. 2016; Qu et al. 2016).