Formation and evolution of ring structures around small bodies in the Solar System...
Probing atmospheres and circumstellar environments of Be stars and evolved low mas...
| Full text | |
| Author(s): Show less - |
Souami, D.
[1, 2]
;
Braga-Ribas, F.
[1, 3, 4, 5]
;
Sicardy, B.
[1]
;
Morgado, B.
[1, 5]
;
Ortiz, J. L.
[6]
;
Desmars, J.
[7, 8]
;
Camargo, J. I. B.
[4, 5]
;
Vachier, F.
[8]
;
Berthier, J.
[8]
;
Carry, B.
[9]
;
Anderson, C. J.
[10, 11]
;
Showers, R.
[11]
;
Thomason, K.
[11]
;
Maley, P. D.
[10, 12]
;
Thomas, W.
[10]
;
Buie, M. W.
[13]
;
Leiva, R.
[13]
;
Keller, J. M.
[14]
;
Vieira-Martins, R.
[4, 5, 8]
;
Assafin, M.
[15, 5]
;
Santos-Sanz, P.
[6]
;
Morales, N.
[6]
;
Duffard, R.
[6]
;
Benedetti-Rossi, G.
[1, 5]
;
Gomes-Junior, A. R.
[16, 5]
;
Boufleur, R.
[4, 5]
;
Pereira, C. L.
[3, 5]
;
Margoti, G.
[3]
;
Pavlov, H.
[10, 17]
;
George, T.
[10]
;
Oesper, D.
[10]
;
Bardecker, J.
[10]
;
Dunford, R.
[10, 18]
;
Kehrli, M.
[19]
;
Spencer, C.
[19]
;
Cota, J. M.
[20]
;
Garcia, M.
[20]
;
Lara, C.
[20]
;
McCandless, K. A.
[20]
;
Self, E.
[20]
;
Lecacheux, J.
[1]
;
Frappa, E.
[21]
;
Dunham, D.
[10]
;
Emilio, M.
[22]
Total Authors: 44
|
| Affiliation: Show less - | [1] Univ Paris Diderot, LESIA UMR 8109, Observatoire Paris, Univ PSL, CNRS, Sorbonne Univ, Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon - France
[2] Univ Namur, NaXys, B-5000 Namur - Belgium
[3] Fed Univ Technol Parana UTFPR, DAFIS, Curitiba, Parana - Brazil
[4] MCTIC, Observ Nacl, Rio De Janeiro - Brazil
[5] Lab Interinst & Astron Line A, Rua Gal Jose Cristino 77, BR-20921400 Rio De Janeiro, RJ - Brazil
[6] IAA CSIC, Inst Astrofis Andalucia, Glorieta Astron S-N, Granada 18008 - Spain
[7] Inst Polytech Sci Avancees IPSA, 63 Blvd Brandebourg, F-94200 Ivry - France
[8] PSL Univ, Sorbonne Univ, Observ Paris, IMCCE CNRS UMR8028, 77 Ave Denfert Rochereau, F-75014 Paris - France
[9] Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Biot - France
[10] Int Occultat Timing Assoc IOTA, POB 7152, Seattle, WA 98042 - USA
[11] Coll Southern Idaho, Twin Falls, ID - USA
[12] NASA, Johnson Space Ctr Astron Soc, Houston, TX - USA
[13] Southwest Res Inst, 1050 Walnut St, Suite 300, Boulder, CO 80302 - USA
[14] Univ Colorado, Boulder, CO 80309 - USA
[15] Univ Fed Rio de Janeiro, Observ Valongo, Rio De Janeiro - Brazil
[16] UNESP Sao Paulo State Univ, Grp Dinam Orbital & Planetol, BR-12516410 Guaratingueta, SP - Brazil
[17] Tangra Observ E24, St Clair - Australia
[18] Jimginny Observ W08, Naperville, IL - USA
[19] Calif Polytech State Univ San Luis Obispo, San Luis Obispo, CA 93407 - USA
[20] Calipatria High Sch, Calipatria, CA - USA
[21] Euraster, 1 Rue Tonnelier, F-46100 Faycelles - France
[22] Univ Estadual Ponta Grossa UEPG, Ponta Grossa, Parana - Brazil
Total Affiliations: 22
|
| Document type: | Journal article |
| Source: | Astronomy & Astrophysics; v. 643, NOV 13 2020. |
| Web of Science Citations: | 0 |
| Abstract | |
Context. We present results from the first recorded stellar occultation by the large trans-Neptunian object (174567) Varda that was observed on September 10, 2018. Varda belongs to the high-inclination dynamically excited population, and has a satellite, Ilmare, which is half the size of Varda.Aims. We determine the size and albedo of Varda and constrain its 3D shape and density.Methods. Thirteen different sites in the USA monitored the event, five of which detected an occultation by the main body. A best-fitting ellipse to the occultation chords provides the instantaneous limb of the body, from which the geometric albedo is computed. The size and shape of Varda are evaluated, and its bulk density is constrained using Varda's mass as is known from previous works.Results. The best-fitting elliptical limb has semi-major (equatorial) axis of (383 +/- 3) km and an apparent oblateness of 0.066 +/- 0.047, corresponding to an apparent area-equivalent radius R `(equiv)=(370 +/- 7) R ` equiv=(370 +/- 7) km and geometric albedo p(v) = 0.099 +/- 0.002 assuming a visual absolute magnitude H-V = 3.81 +/- 0.01. Using three possible rotational periods for the body (4.76, 5.91, and 7.87 h), we derive corresponding MacLaurin solutions. Furthermore, given the low-amplitude (0.06 +/- 0.01) mag of the single-peaked rotational light-curve for the aforementioned periods, we consider the double periods. For the 5.91 h period (the most probable) and its double (11.82 h), we find bulk densities and true oblateness of rho = (1.78 +/- 0.06) g cm(-3), = 0.235 +/- 0.050, and rho = (1.23 +/- 0.04) g cm(-3), = 0.080 +/- 0.049. However, it must be noted that the other solutions cannot be excluded just yet. (AU) | |
| FAPESP's process: | 18/11239-8 - Determination of satellites and rings orbits from analysis of spacecrafts images |
| Grantee: | Altair Ramos Gomes Junior |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |