We perform a study of the spatial and kinematical distribution of young open clusters in the solar neighbourhood, discerning between bound clusters and transient stellar condensations within our sample. Then, we discriminate between Gould Belt (GB) and local Galactic disc (LGD) members, using our previous estimate of the structural parameters...
-
April 5, 2017 (v1)PublicationUploaded on: March 25, 2023
-
July 10, 2017 (v1)Publication
We present a newly developed, three-dimensional spatial classification method, designed to analyze the spatial distribution of early-type stars within the 1 kpc sphere around the Sun. We propose a distribution model formed by two intersecting disks, the Gould Belt (GB) and the local Galactic disk (LGD), defined by their fundamental geometric...
Uploaded on: March 27, 2023 -
July 10, 2017 (v1)Publication
Using the spatial classification method and the structural parameters estimated for the Gould Belt (GB) and the local Galactic disk (LGD) from a previous paper, we have evaluated spatial membership probabilities for a sample of O and B stars from the Hipparcos catalog (Perryman and coworkers) with available proper motions and radial velocity...
Uploaded on: March 27, 2023 -
July 10, 2017 (v1)Publication
The capabilities of CCD uvby photometry for the study of reddened young clusters are investigated. Observations of four fields in the direction of the clusters Basel 1, Berkeley 86, NGC 6704, and NGC 6756, with a total of 1665 stars measured in at least the y and b bands, produce new estimates for the clusters parameters. The results are...
Uploaded on: March 27, 2023 -
July 11, 2017 (v1)Publication
The spatial metallicity distribution in the Galaxy, as depicted by the globular cluster system, is analyzed. Two metallicity maps (on the ω - |Z| plane) corresponding to the halo and disk subsamples (Zinn 1985) have been obtained. The resulting pictures reveal the existence of a highly structured abundance pattern for the two subsystems....
Uploaded on: March 27, 2023 -
July 11, 2017 (v1)Publication
The ages and locations of stellar clusters and individual Cepheid stars in the depression called the "Big Dent" are analyzed. The Z-locations of the cluster sample display a well-defined Z-age stratification. The Cepheid sample has ages between 3 and 8 x 107 yr and shows a departure from the midplane similar to the one observed for clusters of...
Uploaded on: December 4, 2022 -
October 4, 2017 (v1)Publication
On 2013 September 11 at 20h07m28 .s 68 ± 0 .s 01 UTC, two telescopes operated in the framework of our lunar impact flashes monitoring project recorded an extraordinary flash produced by the impact on the Moon of a large meteoroid at selenographic coordinates 17$ $_{.}^{\circ}$$2 ± 0$ $_{.}^{\circ}$$2 S, 20$ $_{.}^{\circ}$$5 ± 0$...
Uploaded on: December 4, 2022 -
July 7, 2017 (v1)Publication
The results of a UBVR photometric study in the field of the open cluster IC 1311 are presented. A comparison with previously published results on NGC 7044, based on measurements secured during the same observing run, leads to self-consistent constraints to the parameters of the cluster. The location of selected samples of giant and unevolved...
Uploaded on: December 4, 2022 -
July 11, 2017 (v1)Publication
he Gould Belt (GB) is a system of gas and young, bright stars distributed along a plane that is inclined with respect to the main plane of the Milky Way. Observational evidence suggests that the GB is our closest star formation complex, but its true nature and origin remain rather controversial. In this work we analyze the fractal structure of...
Uploaded on: December 4, 2022 -
April 2, 2018 (v1)Publication
We present new orbital data and dynamic results pointing towards the origin of the Northern χ -Orionid meteoroid stream, which is a part of the Taurid meteoroid complex. A new software package was developed to establish the potential parent bodies of meteoroid streams based on the similarity of their orbits. The analysis of a Northern χ...
Uploaded on: December 5, 2022 -
June 5, 2017 (v1)Publication
Aims. Our goal is to estimate empirically the cosmic variance that affects merger fraction studies based on close pairs for the first time. Methods. We compute the merger fraction from photometric redshift close pairs with 10 h-1 kpc ≤ rp ≤ 50 h-1 kpc and ?v ≤ 500 km s-1 and measure it in the 48 sub-fields of the ALHAMBRA survey. We study the...
Uploaded on: December 4, 2022 -
September 28, 2017 (v1)Publication
We analyse here two very bright fireballs produced by the ablation in the atmosphere of two large meteoroids in 2009 and 2010. These slow-moving and deep-penetrating events were observed over Spain in the framework of our Spanish Fireball Network continuous meteor monitoring campaign. The analysis of the emission spectrum imaged for one of...
Uploaded on: December 4, 2022 -
September 6, 2017 (v1)Publication
A Geminid fireball with an absolute magnitude of -13 was observed over the south of Spain on 2009 December 15. This extraordinarily bright event (the brightest Geminid ever recorded by our team) was imaged from two meteor observing stations operated by the SPanish Meteor Network (SPMN). The bolide exhibited fast and quasi-periodic variations in...
Uploaded on: March 27, 2023 -
April 2, 2018 (v1)Publication
Accurate orbital data obtained for the recently discovered γ -Ursae Minorids meteoroid stream during the 2010 and 2011 Spanish Meteor Network and Finnish Fireball Network observing ampaigns are presented. In particular, we focus on an outburst detected in 2010 and on the analysis of the first emission spectrum recorded for a...
Uploaded on: March 27, 2023 -
March 27, 2018 (v1)Publication
On 2011 October 8, the Earth crossed dust trails ejected from comet 21P/Giacobini-Zinner in the late 19th and early 20th Century. This gave rise to an outburst in the activity of the October Draconid meteor shower, and an international team was organized to analyse this event. The SPanish Meteor Network (SPMN) joined this initiative and...
Uploaded on: March 27, 2023 -
September 7, 2017 (v1)Publication
A superbolide with an estimated absolute magnitude of-20±1was seen on 2012 July 13 over the centre and south of Spain. This extraordinary event, which was witnessed by numerous casual observers, was recorded in the framework of the continuous fireball monitoring and meteor spectroscopy campaign performed by the SPanish Meteor Network (SPMN)....
Uploaded on: March 27, 2023 -
September 7, 2017 (v1)Publication
Context. Even the spectroscopic capabilities of today's ground and space-based observatories can not keep up with the enormous flow of detections (>10 5 deg -2) unveiled in modern cosmological surveys as: i) would be required enormous telescope time to perform the spectroscopic follow-ups and ii) spectra remain unattainable for the fainter...
Uploaded on: March 25, 2023 -
March 21, 2018 (v1)Publication
We present the analysis of the atmospheric trajectory and orbital data of four bright bolides observed over Spain, one of which is a potential meteorite dropping event. Their absolute magnitude ranges from -10 to -11. Two of these are of sporadic origin, although a Geminid and a Κ-Cygnid fireball are also considered. These eventswere recorded...
Uploaded on: March 25, 2023