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2007 TY430: A Cold Classical Kuiper Belt Type Binary in the Plutino Population
Ragozzine, Darin; Sheppard, Scott S.; Trujillo, Chadwick
Kuiper Belt object 2007 TY430 is the first wide, equal-sized, binary known in the 3:2 mean motion resonance with Neptune. The two components have a maximum separation of about 1 arcsec and are on average less than 0.1 mag different in apparent magnitude with identical ultra-red colors (g - i = 1.49 ± 0.01 mag). Using nearly monthly observations of…
Wide-field Survey of Emission-line Stars in IC 1396
Ishihara, D.; Ueno, M.; Watanabe, M. +3 more
We have made an extensive survey of emission-line stars in the IC 1396 H II region to investigate the low-mass population of pre-main-sequence (PMS) stars. A total of 639 Hα emission-line stars were detected in an area of 4.2 deg2 and their i' photometry was measured. Their spatial distribution exhibits several aggregates near the eleph…
A Hubble Space Telescope Treasury Study of Star-forming Regions in the Local Group. II. Young Stellar Populations in M31
Bianchi, Luciana; Hodge, Paul; Kang, Yongbeom +1 more
We studied the young stellar populations of 22 star-forming regions in the Andromeda galaxy (M31), with Hubble Space Telescope (HST) multi-band imaging from far-UV to I. The regions were selected from Galaxy Evolution Explorer (GALEX) wide-field far-UV imaging; they sample different environments and galactocentric distances from 6 to 22 kpc. They …
HST/ACS Photometry of Old Stars in NGC 1569: The Star Formation History of a nearby Starburst
Aloisi, Alessandra; van der Marel, Roeland P.; Tosi, Monica +3 more
We used Hubble Space Telescope/Advanced Camera for Surveys to obtain deep V- and I-band images of NGC 1569, one of the closest and strongest starburst galaxies in the universe. These data allowed us to study the underlying old stellar population, aimed at understanding NGC 1569's evolution over a full Hubble time. We focus on the less-crowded oute…
Detection and Tracking of Subtle Cloud Features on Uranus
Sromovsky, L. A.; Fry, P. M.; Hammel, H. B. +2 more
The recently updated Uranus zonal wind profile (Sromovsky et al.) samples latitudes from 71° S to 73° N. But many latitudes remain grossly undersampled (outside 20°-45° S and 20°-50° N) due to a lack of trackable cloud features. Offering some hope of filling these gaps is our recent discovery of low-contrast cloud that can be revealed by imaging a…
Optical TiO and VO Band Emission in Two Embedded Protostars: IRAS 04369+2539 and IRAS 05451+0037
Hillenbrand, Lynne A.; Knapp, Gillian R.; Rebull, Luisa M. +2 more
Archival spectra from the Sloan Digital Sky Survey of two optically faint flat-spectrum protostars, IRAS 04369+2539 and IRAS 05451+0037, show strong emission-line features including—notably—clear and broad emission across several molecular bands of TiO and VO. The molecular emission is indicative of dense, warm circumstellar gas and has been seen …
An HST Imaging Survey of Low-mass Stars in the Chamaeleon I Star-forming Region
Apai, D.; Pascucci, I.; Robberto, M. +7 more
We present new Hubble Space Telescope/WFPC2 observations of 20 fields centered around T Tauri stars in the Chamaeleon I star-forming region. Images have been obtained in the F631N ([O I] λ6300), F656N (Hα), and F673N ([S II] λλ6716, 6731) narrow-band filters, plus the Johnson V-band equivalent F547M filter. We detect 31 T Tauri stars falling withi…
NGC 2207/IC 2163: A Grazing Encounter with Large-scale Shocks
Brinks, Elias; Struck, Curtis; Elmegreen, Bruce G. +3 more
Radio continuum, Spitzer infrared, optical, and XMM-Newton X-ray and ultraviolet observations (UVW1 and UVM2) are used to study large-scale shock fronts, young star complexes, and the galactic nuclei in the interacting galaxies NGC 2207/IC 2163. There are two types of large-scale shock fronts in this galaxy pair. The large-scale shock front along …
Physical Structure and Nature of Supernova Remnants in M101
Chu, You-Hua; Gruendl, Robert A.; Chen, C. -H. Rosie +6 more
Supernova remnant (SNR) candidates in the giant spiral galaxy M101 have been previously identified from ground-based Hα and [S II] images. We have used archival Hubble Space Telescope (HST) Hα and broadband images as well as stellar photometry of 55 SNR candidates to examine their physical structure, interstellar environment, and underlying stella…
TA-DA: A Tool for Astrophysical Data Analysis
Da Rio, Nicola; Robberto, Massimo
We present the Tool for Astrophysical Data Analysis (TA-DA), a new software aimed to greatly simplify and improve the analysis of stellar photometric data in comparison with theoretical models, and allow the derivation of stellar parameters from multi-band photometry. Its flexibility allows one to address a number of such problems: from the interp…