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J. Maíz Apellániz

Publications and source records attributed to J. Maíz Apellániz.

At least 55 records · Page 3Linked to original sources
arXiv2021

Hubble spectroscopy of LB-1: comparison with B+black-hole and Be+stripped-star models

LB-1 has variously been proposed as either an X-ray dim B-type star plus black hole (B+BH) binary, or a Be star plus an inflated stripped star (Be+Bstr) binary. The Space Telescope Imaging Spectrograph (STIS) on board HST was used to obtain a flux-calibrated spectrum that is compared with non-LTE spectral energy distributions (SED) and line profiles for the proposed models. The Hubble data, together with the Gaia EDR3 parallax, provide tight constraints on the properties and stellar luminosities of the system. In the case of the Be+Bstr model we adopt the published flux ratio for the Be and Bstr stars, re-determine the T$_{eff}$ of the Bstr using the silicon ionization balance, and infer Teff for the Be star from the fit to the SED. We derive stellar parameters consistent with previous results, but with greater precision enabled by the Hubble SED. While the Be+Bstr model is a better fit to the HeI lines and cores of the Balmer lines in the optical, the B+BH model provides a better fit to the Si iv resonance lines in the UV. The analysis also implies that the Bstr star has roughly twice solar silicon abundance, difficult to reconcile with a stripped star origin. The Be star on the other hand has a rather low luminosity, and a spectroscopic mass inconsistent with its possible dynamical mass. The fit to the UV can be significantly improved by reducing the T$_{eff}$ and radius of the Be star, though at the expense of leading to a different mass ratio. In the B+BH model, the single B-type spectrum is a good match to the UV spectrum. Adopting a mass ratio of 5.1$\pm$0.1 (Liu et al. 2020) implies a BH mass of $\sim$21$^{+9}_{-8}M_{\odot}$.

astro-ph.SR↗
arXiv2021

Validation of the accuracy and precision of Gaia EDR3 parallaxes with globular clusters

CONTEXT. Gaia EDR3 has produced parallaxes for 1.468x10^9 sources but there are calibration issues that require corrections to the published values and uncertainties. AIMS. We want to characterize the behavior of the uncertainties of the Gaia EDR3 parallaxes. We also aim to provide a procedure for the calculation of distances to stars and stellar clusters. METHODS. We reanalyze some of the data in the calibration papers for QSO and LMC parallaxes and combine those results with measurements for six bright GCs. We calculate the angular covariance of EDR3 parallaxes at small separations based on the LMC results and combine it with the results for larger angles using QSOs to obtain an analytical formula for the angular covariance over the whole sky. The results for the six GCs are used to validate the parallax bias correction as a function of magnitude, color, and ecliptic latitude and to determine the constant used to convert internal uncertainties to external ones. RESULTS. The angular covariance at zero separation is 106.2 muas^2, yielding a minimum uncertainty for EDR3 parallaxes of 10.3 muas for individual stars. That value can be only slightly reduced for GCs after considering the behavior of the angular covariance of the parallaxes for small separations. The Lindegren et al. parallax bias correction works quite well, except for the brighter magnitudes, suggesting improvements may be possible there. The value of k is 1.1-1.7 and depends on G. Stars with moderately large values of RUWE can still provide useful parallaxes albeit with larger values of k. We give accurate and precise Gaia EDR3 distances to the six GCs and for the specific case of 47 Tuc we are able to beat the angular covariance limit and derive a high-precision distance of 4.53+-0.06 kpc. Finally, a recipe for the derivation of distances to stars and stellar clusters using Gaia EDR3 parallaxes is given. [ABRIDGED]

astro-ph.IM↗
arXiv2021

The Alma catalog of OB stars. II. A cross-match with Gaia DR2 and an updated map of the solar neighbourhood

We cross-match the Alma catalog of OB stars with Gaia DR2 astrometry and photometry as a first step towards producing a clean sample of massive stars in the solar neighbourhood with a high degree of completeness. We analyze the resulting colour-absolute magnitude diagram to divide our sample into categories and compare extinction estimates from two sources, finding problems with both of them. The distances obtained with three different priors are found to have few differences among them, indicating that Gaia DR2 distances are robust. An analysis of the 3-D distribution of massive stars in the solar neighbourhood is presented. We show that a kinematically distinct structure we dub the Cepheus spur extends from the Orion-Cygnus spiral arm towards the Perseus arm and is located above the Galactic mid-plane, likely being related to the recently discovered Radcliffe wave. We propose that this corrugation pattern in the Galactic disk may be responsible for the recent enhanced star formation at its crests and troughs. We also discuss our plans to extend this work in the immediate future.

astro-ph.SR↗
arXiv2020

Lucky spectroscopy, an equivalent technique to Lucky Imaging: II. Spatially-resolved intermediate-resolution blue-violet spectroscopy of 19 close massive binaries using the William Herschel Telescope

CONTEXT. Many massive stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS. We want to continue obtaining spatially resolved spectroscopy of close massive visual binaries to derive their spectral types. METHODS. We have used lucky spectroscopy to obtain many short long-slit spectroscopic exposures of 19 close visual binaries under good seeing conditions. We selected those with the best characteristics, extracted the spectra using multiple-profile fitting, and combined the results to derive spatially separated spectra. The results are analyzed in combination with data from lucky imaging, regular intermediate-resolution single-order spectroscopy, and échelle high-resolution spectroscopy. RESULTS. The new application of lucky spectroscopy has allowed us to [a] spatially disentangle for the first time two O stars (FN CMa B and 6 Cas B) with brighter BA supergiant companions; [b] determine that two B stars (alpha Sco B and HD 164492 B) with close and more massive companions are fast rotators; [c] extend the technique to cases with extreme magnitude differences, shorter separations, and fainter primary magnitudes down to B=11; [d] spatially disentangle the spectra of stars with companions as diverse as an A supergiant (6 Cas A), a WR star (WR 157), and an M supergiant (alpha Sco A); [e] discover the unexpected identity of some targets such as two previously unknown bright O stars (HD 51756 B and BD +60 544) and a new member of the rare OC category (HD 8768 A); and [f] identify and classify which of the components of four visual binaries is a double-lined spectroscopic binary and for another seven systems detect signs of spectroscopic binarity using high-spectral-resolution spectroscopy. We also present a determination of the limits of the technique. [ABRIDGED]

astro-ph.SR↗
arXiv2020

The Villafranca catalog of Galactic OB groups: I. Systems with O2-O3.5 stars

CONTEXT. The GOSSS spectral classifications and Gaia data have significantly improved our ability to measure distances and determine memberships of stellar groups with OB stars. AIMS. We have started a program to identify, measure distances, and determine the membership of Galactic stellar groups with OB stars. We start with the identification and distance determinations of groups with O stars. In this paper we concentrate on groups that contain stars with the earliest spectral subtypes. METHODS. We use GOSSS to select Galactic stellar groups with O2-O3.5 stars and a method that combines Gaia DR2 photometry, positions, proper motions, and parallaxes to assign robust memberships and measure distances. We also include the two clusters in that paper to generate our first list of 16 O-type Galactic stellar groups. RESULTS. We derive distances, determine the membership, and analyze the structure of sixteen Galactic stellar groups with O stars, Villafranca O-001 to O-016, including the 14 groups with the earliest-O-type optically-accessible stars known in the Milky Way. We compare our distance with previous results and establish that the best consistency is with VLBI parallaxes and the worst is with kinematic distances. Our results indicate that massive stars can form in relatively low-mass clusters or even in near-isolation, as is the case for the Bajamar star in the North America nebula. This lends support to the hierarchical scenario of star formation, where some stars are born in well-defined bound clusters but others are born in associations that are unbound from the beginning: groups of newborn stars come in many shapes and sizes. We propose that HD 64 568 and HD 64 315 AB could have been ejected simultaneously from Villafranca O-012 S. Our results are consistent with a difference of approx. 20 microas in the Gaia DR2 parallax zero point between bright and faint stars. (ABRIDGED)

astro-ph.GA↗
arXiv2020

Spectroscopic characterization of the known O-star population in Cygnus OB2. Evidence of multiple star-forming bursts

Cygnus OB2 provides a unique insight into the high-mass stellar content in one of the largest groups of young massive stars in our Galaxy. Although several studies of its massive population have been carried out over the last decades, an extensive spectroscopic study of the whole known O-star population in the association is still lacking. In this work, we created the most complete spectroscopic census of O stars carried out so far in Cygnus OB2 using already existing and new spectroscopy. We present the spectra for 78 O-type stars, from which we identify new binary systems, obtain the distribution of rotational velocities, and determine the main stellar parameters for all the stars in the region that have not been detected as double-line spectroscopic binaries. We also derive radii, luminosities, and masses for those stars with reliable Gaia astrometry, in addition to creating the Hertzsprung-Russell Diagram to interpret the evolutionary status of the association. This work has shown the improvement reached when using accurate spectroscopic parameters and astrometry for the interpretation of the evolutionary status of a population, revealing, in the case of Cygnus OB2, at least two star-forming bursts at $\sim$3 and $\sim$5 Myr. We find an apparent deficit of very fast rotators in the distribution of rotational velocities. The inspection of the dynamical distribution of the sample has allowed us to identify nine O stars with peculiar proper motions and discuss a possible dynamical ejection scenario or past supernova explosions in the region.

astro-ph.SR↗
arXiv2020

Galactic extinction laws: II. Hidden in plain sight, a new interstellar absorption band at 7700 Å broader than any known DIB

We have detected a broad interstellar absorption band centred close to 7700 Å and with a FWHM of 176.6$\pm$3.9 Å. This is the first such absorption band detected in the optical range and is significantly wider than the numerous diffuse interstellar bands (DIBs). It remained undiscovered until now because it is partially hidden behind the A telluric band produced by O$_2$. The band was discovered using STIS@HST spectra and later detected in a large sample of stars of diverse type (OB stars, BA supergiants, red giants) using further STIS and ground-based spectroscopy. The EW of the band is measured and compared with our extinction and K I $λλ$7667.021,7701.093 measurements for the same sample. The carrier is ubiquitous in the diffuse and translucent Galactic ISM but is depleted in the environment around OB stars. In particular, it appears to be absent or nearly so in sightlines rich in molecular carbon. This behaviour is similar to that of the $σ$-type DIBs, which originate in the low/intermediate-density UV-exposed ISM but are depleted in the high-density UV-shielded molecular clouds. We also present an update on our previous work on the relationship between $E(4405-5495)$ and $R_{5495}$ and incorporate our results into a general model of the ISM.

astro-ph.GA↗
arXiv2020

Galactic extinction laws: I. A global NIR analysis with 2MASS photometry

We have started an ambitious program to determine if the full diversity of extinction laws is real or if some of it is due to calibration or methodological issues. Here we start by analyzing the information on NIR extinction in a 2MASS stellar sample with good quality photometry and very red colours. We calculate the extinction at 1 $μ$m, $A_1$, and the power-law exponent, $α$ ($A_λ= A_1 λ^{-α}$), for the 2MASS stars located in the extinction trajectory in the $H-K$ vs. $J-H$ plane expected for red giants with $A_1 > 5$ mag. We test the validity of the assumption about the nature of those stars, whether a single or multiple values of $α$ are needed, and the spatial variations of the results. Most ($\sim$83%) of those stars can indeed be explained by high-extinction red giants and the rest is composed of extinguished AGB stars (mostly O-rich), blended sources, and smaller numbers of other objects, a contaminant fraction that can be reduced with the help of Gaia} DR2 data. Galactic red giants experience a NIR extinction with $α\sim 2.27$ and an uncertainty of a few hundredths of a magnitude. There is no significant spread in $α$ even though our sample is widely distributed and has a broad range of extinctions. Differences with previous results are ascribed to the treatment of non-linear photometric effects and/or the contaminant correction. Future research should concentrate in finding the correct functional form for the NIR extinction law. In the appendix we detail the treatment of non-linear photometric effects in the 2MASS bands.

astro-ph.GA↗
arXiv2020

The high-energy emission from HD~93129A near periastron

We conducted an observational campaign towards one of the most massive and luminous colliding wind binaries in the Galaxy, HD~93129A, close to its periastron passage in 2018. During this time the source was predicted to be in its maximum of high-energy emission. Here we present our data analysis from the X-ray satellites \textit{Chandra} and \textit{NuSTAR} and the $γ$-ray satellite \textit{AGILE}. High-energy emission coincident with HD~93129A was detected in the X-ray band up to $\sim$18~keV, whereas in the $γ$-ray band only upper limits were obtained. We interpret the derived fluxes using a non-thermal radiative model for the wind-collision region. We establish a conservative upper limit for the fraction of the wind kinetic power that is converted into relativistic electron acceleration, $f_\mathrm{NT,e} < 0.02$. In addition, we set a lower limit for the magnetic field in the wind-collision region as $B_\mathrm{WCR} > 0.3$~G. We also argue a putative interpretation of the emission from which we estimate $f_\mathrm{NT,e} \approx 0.006$ and $B_\mathrm{WCR} \approx 0.5$~G. We conclude that multi-wavelength, dedicated observing campaigns during carefully selected epochs are a powerful tool for characterising the relativistic particle content and magnetic field intensity in colliding wind binaries.

astro-ph.HE↗
arXiv2020

Spatially resolved spectroscopy of close massive visual binaries with HST/STIS: I. Seven O-type systems

CONTEXT. Many O-type stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS. We want to obtain spatially resolved spectroscopy of close O-type visual binaries to derive their spectral types. METHODS. We use the Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) to obtain long-slit blue-violet spectroscopy of eight Galactic O-type stars with nearby visual companions and use spatial-profile fitting to extract the separate spectra. We also use the ground-based Galactic O-Star Spectroscopic Survey (GOSSS) to study more distant visual components. RESULTS. We spatially resolve seven of the eight systems, present spectra for their components, and obtain their spectral types. Those seven multiple systems are iota Ori Aa,Ab,B, 15 Mon Aa,Ab,C, tau CMa Aa,Ab,B,C,D,E, HD 206 267 Aa,Ab,C,D, HD 193 443 A,B, HD 16 429 Aa,Ab, and IU Aur A,B. This is the first time that spatially resolved spectroscopy of the close visual binaries of those systems is obtained. We establish the applicability of the technique as a function of the separation and magnitude difference of the binary.

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arXiv2020

A detailed non-LTE analysis of LB-1: Revised parameters and surface abundances

LB-1 has recently been proposed to be a binary system at 4 kpc consisting of a B star of 8 Msol and a massive stellar black hole of 70 Msol. This finding challenges our current theories of massive star evolution and formation of BHs at solar metallicity. Our objective is to derive the effective temperature, surface gravity and chemical composition of the B-type component in order to determine its nature and evolutionary status and, indirectly, to constrain the mass of the BH. We use the non-LTE stellar atmosphere code FASTWIND to analyse new and archival high resolution data. We determine (Teff, logg) values of (14000$\pm500$ K, 3.50$\pm0.15$ dex) that, combined with the Gaia parallax, implies a spectroscopic mass, from logg, of $3.2^{+2.1}_{-1.9}$ Msol and an evolutionary mass, assuming single star evolution, of $5.2^{+0.3}_{-0.6}$ Msol. We determine an upper limit of 8 km/s for the projected rotational velocity and derive the surface abundances, finding the star to have a silicon abundance below solar, to be significantly enhanced in nitrogen and iron, and depleted in carbon and magnesium. Complementary evidence derived from a photometric extinction analysis and Gaia yields similar results for Teff and logg and a consistent distance around 2~kpc. We propose that the B star is a slightly evolved main sequence star of 3-5 Msol with surface abundances reminiscent of diffusion in late B/A chemically peculiar stars with low rotational velocities. There is also evidence for CN-processed material in its atmosphere. These conclusions rely critically on the distance inferred from the Gaia parallax. The goodness of fit of the Gaia astrometry also favours a high-inclination orbit. If the orbit is edge-on and the B star has a mass of 3-5 Msol, the mass of the dark companion would be 4-5 Msol, which would be easier to explain with our current stellar evolutionary models.

astro-ph.SR↗
arXiv2019

Gaia DR2 distances to Collinder 419 and NGC 2264 and new astrometric orbits for HD 193 322 Aa,Ab and 15 Mon Aa,Ab

[ABRIDGED] CONTEXT: Gaia DR2 has opened a trove of astrometric and photometric data for Galactic clusters close to the Sun. Lucky imaging has been an operational technique to measure the positions of visual binary systems for a decade and a half, enough to apply its results to the calculation of orbits of some massive multiple systems within ~1 kpc of the Sun. AIMS: We are measuring distances to Galactic stellar groups containing O stars and I start with two of them: Collinder 419 in Cygnus and NGC 2264 in Monoceros. I also aim to derive new astrometric orbits for the Aa,Ab components for the main ionizing sources for both clusters: HD 193 322 and 15 Mon, respectively. METHODS: First, I present a method that uses Gaia DR2 photometry, positions, proper motions, and parallaxes to obtain the membership and distance of a stellar group and apply it to Collinder 419 and NGC 2264. Second, I present a new code that calculates astrometric orbits by searching the whole 7-parameter orbit space and apply it to HD 193 322 Aa,Ab and 15 Mon Aa,Ab using as input literature data from the Washington Double Star Catalog (WDS) and the AstraLux measurements recently presented by Maíz Apellániz et al. (2019). RESULTS: I obtain Gaia DR2 distances of 1006+37-34 pc for Collinder 419 and 719+-16 pc for NGC 2264, with the main contribution to the uncertainties coming from the spatial covariance of the parallaxes. The two NGC 2264 subclusters are at the same distance (within the uncertainties) and they show a significant relative proper motion. The distances are shown to be robust. HD 193 322 Aa,Ab follows an eccentric (e = 0.58+0.03-0.04) orbit with a period of 44+-1 a and the three stars it contains have a total mass of 76.1+9.9-7.4 M_Sol. The orbit of 15 Mon Aa,Ab is even more eccentric (e = 0.770+0.023-0.030), with a period of 108+-12 a and a total mass of 45.1+3.6-3.3 M_Sol for its two stars.

astro-ph.SR↗
arXiv2019

J-PLUS: photometric calibration of large area multi-filter surveys with stellar and white dwarf loci

We present the photometric calibration of the twelve optical passbands observed by the Javalambre Photometric Local Universe Survey (J-PLUS). The proposed calibration method has four steps: (i) definition of a high-quality set of calibration stars using Gaia information and available 3D dust maps; (ii) anchoring of the J-PLUS gri passbands to the Pan-STARRS photometric solution, accounting for the variation of the calibration with the position of the sources on the CCD; (iii) homogenization of the photometry in the other nine J-PLUS filters using the dust de-reddened instrumental stellar locus in (X - r) versus (g - i) colours, where X is the filter to calibrate. The zero point variation along the CCD in these filters was estimated with the distance to the stellar locus. Finally, (iv) the absolute colour calibration was obtained with the white dwarf locus. We performed a joint Bayesian modelling of eleven J-PLUS colour-colour diagrams using the theoretical white dwarf locus as reference. This provides the needed offsets to transform instrumental magnitudes to calibrated magnitudes outside the atmosphere. The uncertainty of the J-PLUS photometric calibration, estimated from duplicated objects observed in adjacent pointings and accounting for the absolute colour and flux calibration errors, are ~19 mmag in u, J0378 and J0395, ~11 mmag in J0410 and J0430, and ~8 mmag in g, J0515, r, J0660, i, J0861, and z. We present an optimized calibration method for the large area multi-filter J-PLUS project, reaching 1-2% accuracy within an area of 1 022 square degrees without the need for long observing calibration campaigns or constant atmospheric monitoring. The proposed method will be adapted for the photometric calibration of J-PAS, that will observe several thousand square degrees with 56 narrow optical filters.

astro-ph.IM↗
arXiv2019

MONOS: Multiplicity Of Northern O-type Spectroscopic systems. I. Project description and spectral classifications and visual multiplicity of previously known objects

[ABRIDGED] AIMS. MONOS is collecting information and studying O-type spectroscopic binaries with delta > -20 deg. In this 1st paper we describe the sample and provide spectral classifications and additional information for objects with previous SB or EB orbits. In the future we will test the validity of previous solutions and calculate new SB orbits. METHODS.The spectra in this paper have 2 sources: GOSSS, which is obtaining blue-violet R~2500 spectroscopy of thousands of massive stars, and LiLiMaRlin, a library of libraries of high-resolution spectroscopy of massive stars obtained from 4 different surveys and additional data from our own observing programs and public archives. We also use lucky images from AstraLux. RESULTS. We present homogeneous spectral classifications for 92 O-type spectroscopic multiple systems and 10 optical companions. We discuss the visual multiplicity of each system with the support of AstraLux images and additional sources. For 11 O-type objects and for 6 B-type objects we present their first GOSSS spectral classifications. For 2 known EBs we detect SB2/SB1 lines for the first time, to which we add a third system already reported by us recently. For 2 previous SB1 systems we detect their SB2 nature for the first time and give their first separate spectral classifications, something we also do for a 3rd object just recently identified as a SB2. We also detect 9 new astrometric companions and provide updated information on several others. For sigma Ori AaAbB we provide spectral classifications for the 3 components with a single observation for the first time thanks to a lucky spectroscopy observation obtained close to the Aa,Ab periastron and for theta^1 Ori CaCb we add it to the class of Galactic Of?p stars, raising the number of its members to 6. Our sample of O-type spectroscopic binaries contains more triple/higher-order systems than double systems.

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arXiv2019

The GALANTE Photometric System

This paper describes the characterization of the GALANTE photometric system, a seven intermediate- and narrow-band filter system with a wavelength coverage from 3000 $Å$ to 9000 $Å$ . We describe the photometric system presenting the full sensitivity curve as a product of the filter sensitivity, CCD, telescope mirror, and atmospheric transmission curves, as well as some first- and second-order moments of this sensitivity function. The GALANTE photometric system is composed of four filters from the J-PLUS photometric system, a twelve broad-to-narrow filter system, and three exclusive filters, specifically designed to measure the physical parameters of stars such as effective temperature $T_{\rm eff}$, $\log(g)$, metallicity, colour excess $E(4405-5495)$, and extinction type $R_{5495}$. Two libraries, the Next Generation Spectral Library (NGSL) and the one presented in Maíz Apellániz & Weiler (2018), have been used to determine the transformation equations between the Sloan Digital Sky Survey ($\textit{SDSS}$) $\textit{ugriz}$ photometry and the GALANTE photometric system. We will use this transformation to calibrate the zero points of GALANTE images. To this end, a preliminary photometric calibration of GALANTE has been made based on two different $\textit{griz}$ libraries ($\textit{SDSS}$ DR12 and ATLAS All-Sky Stellar Reference Catalog, hereinafter $\textit{RefCat2}$). A comparison between both zero points is performed leading us to the choice of $\textit{RefCat2}$ as the base catalogue for this calibration, and applied to a field in the Cyg OB2 association.

astro-ph.IM↗
arXiv2018

Extreme resonance line profile variations in the ultraviolet spectra of NGC 1624-2: probing the giant magnetosphere of the most strongly magnetized known O-type star

In this paper, we present high-resolution HST/COS observations of the extreme magnetic O star NGC 1624-2. These represent the first ultraviolet spectra of this archetypal object. We examine the variability of its wind-sensitive resonance lines, comparing it to that of other known magnetic O stars. In particular, the observed variations in the profiles of the CIV and SiIV doublets between low state and high state are the largest observed in any magnetic O-type star, consistent with the expected properties of NGC 1624-2's magnetosphere. We also observe a redshifted absorption component in the low state, a feature not seen in most stars. We present preliminary modelling efforts based on the Analytic Dynamical Magnetosphere (ADM) formalism, demonstrating the necessity of using non-spherically symmetric models to determine wind/magnetospheric properties of magnetic O stars.

astro-ph.SR↗
arXiv2018

GALANTE: finding all the optically accessible Galactic O+B+WR stars in the Galactic Plane

GALANTE is an optical photometric survey with seven intermediate/narrow filters that has been covering the Galactic Plane since 2016 using the Javalambre T80 and Cerro Tololo T80S telescopes. The P.I.s of the northern part (GALANTE NORTE) are Emilio J. Alfaro and Jesús Maíz Apellániz. and the P.I. of the southern part (GALANTE SUR) is Rodolfo H. Barbá. The detector has a continuous 1.4 degr x 1.4 degr field of view with a sampling of 0.55"/pixel and the seven filters are optimized to detect obscured early-type stars. The survey includes long, intermediate, short, and ultrashort exposure times to reach a dynamical range close to 20 magnitudes, something never achieved for such an optical project before. The characteristics of GALANTE allow for a new type of calibration scheme using external Gaia, Tycho-2, and 2MASS data that has already led to a reanalysis of the sensitivity of the Gaia G filter. We describe the project and present some early results. GALANTE will identify the majority of the early-type massive stars within several kpc of the Sun and measure their amount and type of extinction. It will also map the Halpha nebular emission, identify emission-line stars, and do other studies of low- and intermediate-mass stars.

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