Astronomische Nachrichten最新文献

{"title":"PERICLES: A Set of Empirical Rotational Isochrones Modeled on Cool Dwarfs in Open Clusters and Wide Binaries","authors":"David Gruner,&nbsp;Sydney A. Barnes","doi":"10.1002/asna.70056","DOIUrl":"10.1002/asna.70056","url":null,"abstract":"<p>Isochrones, equal-age curves, are widely used in astrophysics to estimate stellar ages. Classical stellar parameters are, however, very limited in their usability for main sequence stars because of their weak age-dependence. Here, rotation period measurements provide complementary information. We construct and present a set of rotational isochrones, named the Potsdam Empirical Rotational Isochrones from CLustEr Stars (<span>Pericles</span>), that leverage rotation periods. They are constructed empirically using stars in well-studied open clusters and a small number of complementary field stars. The rotational isochrones span the main sequence stars from late-F type near the Kraft break to the fully-convective boundary around M3 stars, and are available for ages ≤ 6 Gyr. We also discuss a limitation to such color- or temperature based rotational isochrones, together with ideas to overcome it.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146083332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SN 2021adlw: Supernova or LBV Outburst?","authors":"D. Yu. Tsvetkov,&nbsp;N. N. Pavlyuk,&nbsp;N. P. Ikonnikova,&nbsp;M. A. Burlak,&nbsp;A. A. Belinski,&nbsp;A. V. Dodin,&nbsp;S. A. Potanin,&nbsp;N. I. Shatsky,&nbsp;V. A. Echeistov","doi":"10.1002/asna.70069","DOIUrl":"10.1002/asna.70069","url":null,"abstract":"<div>\u0000 \u0000 <p>We present low-resolution optical spectroscopic and photometric observations of SN 2021adlw. The photometric monitoring in <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>U</mi>\u0000 <mspace></mspace>\u0000 <mi>BV</mi>\u0000 <mspace></mspace>\u0000 <mi>gri</mi>\u0000 </mrow>\u0000 <annotation>$$ Ukern0.5em BVkern0.5em gri $$</annotation>\u0000 </semantics></math> filters continued for 122 days and 2 spectra were collected. The early spectrum allowed to classify the transient as SN IIn, but later it was supposed that it was an outburst of LBV. The spectra and color curves of SN 2021adlw reveal high extinction in the host galaxy, for which we give an estimate <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>E</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mrow>\u0000 <mi>B</mi>\u0000 <mo>−</mo>\u0000 <mi>V</mi>\u0000 </mrow>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <mo>=</mo>\u0000 <mn>0.56</mn>\u0000 <mo>±</mo>\u0000 <mn>0.15</mn>\u0000 </mrow>\u0000 <annotation>$$ Eleft(B-Vright)=0.56pm 0.15 $$</annotation>\u0000 </semantics></math> mag. The spectra before maximum show lines of HI with narrow peaks and wide wings, with FWHM about 350 and 3000 km·s⁻¹, respectively. SN 2021adlw displays typical for most of SNe IIn photometric evolution: long rise to the maximum and slow, nearly linear brightness decline. The peak absolute magnitude is <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mi>V</mi>\u0000 </msub>\u0000 <mo>=</mo>\u0000 <mo>−</mo>\u0000 <mn>16.8</mn>\u0000 <mo>±</mo>\u0000 <mn>0.45</mn>\u0000 <mspace></mspace>\u0000 <mi>mag</mi>\u0000 </mrow>\u0000 <annotation>$$ {M}_V=-16.8pm 0.45 mathrm{mag} $$</annotation>\u0000 </semantics></math>. We propose SN 2021adlw is a low-luminosity type IIn supernova.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146091535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cover Picture: Astron. Nachr. 9/2025","authors":"","doi":"10.1002/asna.70058","DOIUrl":"https://doi.org/10.1002/asna.70058","url":null,"abstract":"<p>In this Original Article L.R. Bedin et. al. present groundbreaking observations made possible by the James Webb Space Telescope: https://onlinelibrary.wiley.com/doi/10.1002/asna.70042\u0000 \u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 9","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70058","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145476375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Barium Abundances of A–F–G Type Stars in the Hyades Cluster","authors":"Yoichi Takeda","doi":"10.1002/asna.70060","DOIUrl":"https://doi.org/10.1002/asna.70060","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 &lt;p&gt;With an aim of clarifying the extent and parameter-dependence of compositional anomaly of barium in A-type stars, Ba abundances were spectroscopically determined based on Ba &lt;span&gt;ii&lt;/span&gt; 6141/6496 lines for 89 (23 A-type and 66 F–G-type) main-sequence stars belonging to the members of Hyades cluster by taking into account the non-LTE effect and the hyper-fine-structure effect. While the non-LTE effect tends to strengthen lines in G stars, it acts in the direction of line weakening in the regime of A stars due to increasing importance of overionization. The Ba abundances of G stars turned out almost constant (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;⟨&lt;/mo&gt;\u0000 &lt;mi&gt;A&lt;/mi&gt;\u0000 &lt;mo&gt;⟩&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;2.33&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ leftlangle Arightrangle =2.33 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), indicating that the primordial composition of Ba in Hyades is mildly supersolar by &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≃&lt;/mo&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;mn&gt;0.2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ simeq +0.2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; dex. In contrast, A-type stars show Ba overabundances of considerably large dispersion (0 &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ lesssim $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; [Ba/H] &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ lesssim 2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;). Since this Ba excess tends to increase with an increase/decrease in &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;mi&gt;eff&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {T}_{mathrm{eff}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;/&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;v&lt;/mi&gt;\u0000 &lt;mi&gt;e&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;sin&lt;/mi&gt;\u0000 &lt;mi&gt;i&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {v}_{mathrm{e}}sin i $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, these two parameters may be essential for producing or controlling the anomaly. Regarding Hyades F-type stars, their Ba abundances are not uniform but show a broad depression (by &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;mn&gt;0.3&lt;/mn&gt;\u0000 &lt;/mr","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146091118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Barium Abundances of A–F–G Type Stars in the Hyades Cluster","authors":"Yoichi Takeda","doi":"10.1002/asna.70060","DOIUrl":"https://doi.org/10.1002/asna.70060","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 &lt;p&gt;With an aim of clarifying the extent and parameter-dependence of compositional anomaly of barium in A-type stars, Ba abundances were spectroscopically determined based on Ba &lt;span&gt;ii&lt;/span&gt; 6141/6496 lines for 89 (23 A-type and 66 F–G-type) main-sequence stars belonging to the members of Hyades cluster by taking into account the non-LTE effect and the hyper-fine-structure effect. While the non-LTE effect tends to strengthen lines in G stars, it acts in the direction of line weakening in the regime of A stars due to increasing importance of overionization. The Ba abundances of G stars turned out almost constant (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;⟨&lt;/mo&gt;\u0000 &lt;mi&gt;A&lt;/mi&gt;\u0000 &lt;mo&gt;⟩&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;2.33&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ leftlangle Arightrangle =2.33 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), indicating that the primordial composition of Ba in Hyades is mildly supersolar by &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≃&lt;/mo&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;mn&gt;0.2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ simeq +0.2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; dex. In contrast, A-type stars show Ba overabundances of considerably large dispersion (0 &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ lesssim $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; [Ba/H] &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ lesssim 2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;). Since this Ba excess tends to increase with an increase/decrease in &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;mi&gt;eff&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {T}_{mathrm{eff}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;/&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;v&lt;/mi&gt;\u0000 &lt;mi&gt;e&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;sin&lt;/mi&gt;\u0000 &lt;mi&gt;i&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {v}_{mathrm{e}}sin i $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, these two parameters may be essential for producing or controlling the anomaly. Regarding Hyades F-type stars, their Ba abundances are not uniform but show a broad depression (by &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;mn&gt;0.3&lt;/mn&gt;\u0000 &lt;/mr","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146091117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information: Astron. Nachr. 9/2025","authors":"","doi":"10.1002/asna.70057","DOIUrl":"https://doi.org/10.1002/asna.70057","url":null,"abstract":"","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 9","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70057","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145476413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"System of Fundamental Rotations of the Object (216) Kleopatra","authors":"V. I. Borodin,&nbsp;M. A. Bubenchikov,&nbsp;A. M. Bubenchikov,&nbsp;D. V. Mamontov,&nbsp;O. D. Nosyrev,&nbsp;S. G.-T. Tsydipov","doi":"10.1002/asna.70061","DOIUrl":"10.1002/asna.70061","url":null,"abstract":"<div>\u0000 \u0000 <p>A highly accurate method for calculating angular dynamics is proposed that appeals to the full tensor of inertia of the body and uses an inertial basis to describe the motion. The use of this method allowed us to identify the system of spin states of the object (216) Kleopatra. It turned out that the most probable mode of inertial rotation of the asteroid is the elliptical precession mode. An estimate is given for the magnitude of the probability of this mode being realized.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146083250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radial Velocity Monitoring and Analysis of Gaia Astrometry of Selected Intermediate Mass Stars to Constrain Their Multiplicity Status","authors":"J. Bätz,&nbsp;M. Mugrauer,&nbsp;K.-U. Michel,&nbsp;J. Reichert,&nbsp;A. Tschirschky,&nbsp;L. Pietsch,&nbsp;F. Edelmann,&nbsp;R. Neuhäuser","doi":"10.1002/asna.70055","DOIUrl":"10.1002/asna.70055","url":null,"abstract":"<p>We present new radial velocity measurements of 13 selected intermediate mass stars (2–6 M_⊙). The measurements were performed between 29 April and 6 September 2024 at the University Observatory Jena using the échelle spectrograph FLECHAS. The radial velocity of eight stars was found to be constant during our spectroscopic monitoring, namely: 17 Dra A, HD 148374, HD 169487 A, 57 Cnc, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>γ</mi>\u0000 </mrow>\u0000 <annotation>$$ gamma $$</annotation>\u0000 </semantics></math> And, HD 11031, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>κ</mi>\u0000 </mrow>\u0000 <annotation>$$ kappa $$</annotation>\u0000 </semantics></math> And, and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>λ</mi>\u0000 </mrow>\u0000 <annotation>$$ lambda $$</annotation>\u0000 </semantics></math> Cas. In contrast, the radial velocity of five stars showed significant variability throughout or spectroscopic observation, namely: 7 CrB A, 7 CrB B, HD 214007, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ι</mi>\u0000 </mrow>\u0000 <annotation>$$ iota $$</annotation>\u0000 </semantics></math> Her, and HD 201433 A. In all these cases, Keplerian orbital solutions were fitted to the observational data and the orbital elements of these spectroscopic binary systems were determined. In addition, we searched for wide companions of our targets using the third data release from ESA's Gaia mission, in order to determine the multiplicity status of these stars and contribute to the census of bright, nearby multiple stars.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"347 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146096446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectral Diversity on (7) Iris and (10) Hygiea Revealed by Broadband Colors","authors":"Alberto Silva Betzler,&nbsp;Orahcio Felicio de Sousa","doi":"10.1002/asna.70054","DOIUrl":"https://doi.org/10.1002/asna.70054","url":null,"abstract":"<div>\u0000 \u0000 <p>We present evidence of surface spectral diversity on asteroids (7) Iris and (10) Hygiea based on Johnson–Cousins (B–V, V–R) and ATLAS (c–o) color indices. For Iris, B–V shows significant rotational modulation, revealing localized heterogeneities associated with features such as the Xanthos and Porphyra craters. Its B–R spectral slope, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>6.4</mn>\u0000 <mo>%</mo>\u0000 </mrow>\u0000 <annotation>$$ 6.4% $$</annotation>\u0000 </semantics></math> per <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>100</mn>\u0000 <mspace></mspace>\u0000 <mi>nm</mi>\u0000 </mrow>\u0000 <annotation>$$ 100kern0.5em mathrm{nm} $$</annotation>\u0000 </semantics></math>, matches that of Q/S-type asteroids, while phase-resolved variations suggest combined effects of composition, topography, and illumination geometry. In contrast, Hygiea is spectrally uniform: neither B–V nor V–R varies with rotation, and its B–R slope, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>3.1</mn>\u0000 <mo>%</mo>\u0000 </mrow>\u0000 <annotation>$$ 3.1% $$</annotation>\u0000 </semantics></math> per <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>100</mn>\u0000 <mspace></mspace>\u0000 <mi>nm</mi>\u0000 </mrow>\u0000 <annotation>$$ 100kern0.5em mathrm{nm} $$</annotation>\u0000 </semantics></math>, is typical of the B/C-complex. The c–o distributions for both objects do not show a clear dependence on Earth-based viewing geometry. We estimate the c–o index of near-Earth asteroid <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>2024</mn>\u0000 <mspace></mspace>\u0000 <msub>\u0000 <mi>YR</mi>\u0000 <mn>4</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 2024 {mathrm{YR}}_4 $$</annotation>\u0000 </semantics></math> as 0.5, consistent with a redder K/L-type surface. This result indicates that c–o can discriminate between S- and C-complex asteroids, similar to V–R. These findings demonstrate the diagnostic value of broadband colors for characterizing asteroid surfaces and provide new insights into the compositional and evolutionary diversity of main-belt asteroids.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 10","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145779510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information: Astron. Nachr. 7/2025","authors":"","doi":"10.1002/asna.70051","DOIUrl":"https://doi.org/10.1002/asna.70051","url":null,"abstract":"","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 7-8","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145135662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}