Statistical analysis of asteroid taxonomic signatures from magnitude phase function

<p>According the H-G magnitude system ,this work using the known spectral-type asteroids (about three hundreds asteroids including MBAs and NEAs) found from literature, we derived the new G-value of two main taxonomic groups in both g and r filters (In g filter, C-type is 0.095&#177;0.112, and S-type is 0.257&#177;0.165. In r filter, C-type is 0.091&#177;0.134, and S-type is 0.280&#177;0.158). We then used these values to identify the unknown taxonomic near-Earth asteroids(NEAs) obtained by (ZTF) from June 2018 to May 2020. In total, more than one hundred NEAs had been classified into C- and S-complex. In addition, the investigation of size distribution in NEAs found that the C-complex asteroids are relatively larger than S-complex asteroids, probably due to observational bias (albedo).</p>

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The statistical analysis of the sand grain size distribution of Al- Ubay-lah barchan dunes, Northwestern Ar-Rub-Alkhali desert, Saudi Arabia

GeoJournal ◽

10.1007/bf00212712 ◽

1986 ◽

Vol 13 (2) ◽

pp. 103-109 ◽

Cited By ~ 7

Author(s):

YahyaMohammedSheikh Abolkhair

Keyword(s):

Grain Size ◽

Saudi Arabia ◽

Statistical Analysis ◽

Size Distribution ◽

Grain Size Distribution ◽

Barchan Dunes ◽

Sand Grain Size

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Near-Earth asteroids spectroscopic survey at Isaac Newton Telescope

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935006 ◽

2019 ◽

Vol 627 ◽

pp. A124 ◽

Cited By ~ 6

Author(s):

M. Popescu ◽

O. Vaduvescu ◽

J. de León ◽

R. M. Gherase ◽

J. Licandro ◽

...

Keyword(s):

Radiation Effects ◽

Practical Reasons ◽

Main Process ◽

Absolute Deviation ◽

Orbital Parameters ◽

Isaac Newton ◽

General Terms ◽

Isaac Newton Telescope ◽

C Complex ◽

Near Earth Asteroids

Context. The population of near-Earth asteroids (NEAs) shows a large variety of objects in terms of physical and dynamical properties. They are subject to planetary encounters and to strong solar wind and radiation effects. Their study is also motivated by practical reasons regarding space exploration and long-term probability of impact with the Earth. Aims. We aim to spectrally characterize a significant sample of NEAs with sizes in the range of ~0.25–5.5 km (categorized as large), and search for connections between their spectral types and the orbital parameters. Methods. Optical spectra of NEAs were obtained using the Isaac Newton Telescope (INT) equipped with the IDS spectrograph. These observations are analyzed using taxonomic classification and by comparison with laboratory spectra of meteorites. Results. A total number of 76 NEAs were observed. We spectrally classified 44 of them as Q/S-complex, 16 as B/C-complex, eight as V-types, and another eight belong to the remaining taxonomic classes. Our sample contains 27 asteroids categorized as potentially hazardous and 31 possible targets for space missions including (459872) 2014 EK24, (436724) 2011 UW158, and (67367) 2000 LY27. The spectral data corresponding to (276049) 2002 CE26 and (385186) 1994 AW1 shows the 0.7 μm feature which indicates the presence of hydrated minerals on their surface. We report that Q-types have the lowest perihelia (a median value and absolute deviation of 0.797 ± 0.244 AU) and are systematically larger than the S-type asteroids observed in our sample. We explain these observational evidences by thermal fatigue fragmentation as the main process for the rejuvenation of NEA surfaces. Conclusions. In general terms, the taxonomic distribution of our sample is similar to the previous studies and matches the broad groups of the inner main belt asteroids. Nevertheless, we found a wide diversity of spectra compared to the standard taxonomic types.

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ANALYSIS OF MORPHOLOGICAL GROUPINGS USING ANOPA, A PATTERN RECOGNITION AND MULTIVARIATE STATISTICAL METHOD: A CASE STUDY INVOLVING CENTRARCHID FISHES

Journal of Biological System ◽

10.1142/s0218339004001117 ◽

2004 ◽

Vol 12 (02) ◽

pp. 137-167 ◽

Cited By ~ 3

Author(s):

DAVID P. CAVANAUGH ◽

RICHARD V. STERNBERG

Keyword(s):

Pattern Recognition ◽

Statistical Analysis ◽

A Priori ◽

Three Dimensional ◽

Discrete Subgroups ◽

Multivariate Statistical ◽

Fish Family ◽

Cohesive Group ◽

Statistical Analysis Method ◽

Taxonomic Groups

Morphological relationships within and among taxonomic groups can be very complicated, with anatomical data often supporting two or more incongruent groupings. One possibility is that incongruent character states are taxonomically informative, although in an N-dimensional taxic space. To test the above, morphological relationships of centrarchid fish species were examined using a new pattern recognition, multivariate correlation, and multivariate statistical analysis method (ANOPA). The objective of ANOPA is to identify N-dimensional pattern space correlations among character states, relations that cannot be detected with standard phenetic or phylogenetic approaches. ANOPA provides a solution to an inherent weakness in statistical analysis which occurs in the face of set classification ambiguity, where there is no a priori reason to assign a membership or class identification within multivariate statistical groups. This approach revealed the percoid fish family Centrarchidae to be a statistically significant, cohesive group with complicated internal relationships. Centrarchid taxa are resolved into three major generic aggregates by two and three-dimensional ANOPA, and discrete subgroups were also detected. The complex interrelationships within the Centrarchidae cannot be readily collapsed to a bifurcating tree-structure, explaining the multitude of conflicting phylogenetic hypotheses that have been presented. This is the first robust study of anatomical disparity in teleostean fishes. Applications of ANOPA to the study of morphological gaps, complex taxonomic patterns, and anatomical disparity are discussed.

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Statistical Analysis of Grain Size Distribution in Pleistocene Sediments from Lake Biwa, Japan

Quaternary Research ◽

10.1016/0033-5894(88)90084-1 ◽

1988 ◽

Vol 30 (1) ◽

pp. 12-18 ◽

Cited By ~ 7

Author(s):

Kenji Kashiwaya ◽

Atsuyuki Yamamoto ◽

Kaoru Fukuyama

Keyword(s):

Time Series ◽

Grain Size ◽

Statistical Analysis ◽

Size Distribution ◽

Lake Biwa ◽

Size Distributions ◽

Solar Insolation ◽

The Past ◽

Grain Size Distributions ◽

Milankovitch Theory

Time series of grain-size distributions from Pleistocene sediments deposited in Lake Biwa during the past 550 millennia show dominant periods of 40,000 and 20,000 yr that are very close to those predicted by the Milankovitch theory, as well as a period of about 70,000 yr not directly predicted by this theory. The 70,000-yr period is strongest, followed by the 20,000-yr period. The sequences also show that coarser particles were deposited, in general, during strong solar insolation, whereas finer particles were deposited during weak insolation.

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