Multiwavelength observations of a bright impact flash during the January 2019 total lunar eclipse

We discuss here a lunar impact flash recorded during the total lunar eclipse that occurred on 2019 January 21, at 4h 41m 38.09 +- 0.01 s UT. This is the first time ever that an impact flash is unambiguously recorded during a lunar eclipse and discussed in the scientific literature, and the first time that lunar impact flash observations in more than two wavelengths are reported. The impact event was observed by different instruments in the framework of the MIDAS survey. It was also spotted by casual observers that were taking images of the eclipse. The flash lasted 0.28 seconds and its peak luminosity in visible band was equivalent to the brightness of a mag. 4.2 star. The projectile hit the Moon at the coordinates 29.2 +- 0.3 $^{\circ}$S, 67.5 +- 0.4 $^{\circ}$W. In this work we have investigated the most likely source of the projectile, and the diameter of the new crater generated by the collision has been calculated. In addition, the temperature of the lunar impact flash is derived from the multiwavelength observations. These indicate that the blackbody temperature of this flash was of about 5700 K.Comment: Accepted for publication in MNRAS on 2019 March 2

Development of Interactive Materials by Engineering Students Using the Descartes Applets.

In a degree course such as Forestry Engineering, the general teaching objectives consist of explaining and helping students to understand the principles of Mechanics. For some time now we have encountered significant difficulties in teaching this subject due to the students' lack of motivation and to their insufficient prior preparation for the topic. If we add to this the discipline's inherent complexity and the students' preconceptions about the subject, these teaching difficulties become considerable. For this reason a series of didactic activities have been introduced sequentially in the teaching of this subject. This work describes the methodology, procedure and results for the action of developing a work project in groups using Descartes software. The results of this experiment can be considered very positive. Some of the critical preconceptions for learning the subject can be corrected, and the tutoring process in the classroom contributes to an improvement in teacherstudent communication. Since this scheme was established, the number of students taking part each academic year has increased, and this is the group with the greatest percentage of passing scores

De Flora Valentina, XV

Se comunican los hallazgos de una serie de especies de plantas vasculares detectadas en la provincia de Valencia, principalmente en la comarca del Valle de Ayora, que resultan novedosas o poco conocidas en la mismaSeveral new or rare taxa of vascular plants found in the west of the province of Valencia (E Spain) are here commente

De Flora Valentina, XVI

Several new or rare taxa of vascular plants found in the west of the Valencia region (E Spain) are here commented

Clasificación supervisada para consulta temática en Twitter

Diariamente, la plataforma de microblogging Twitter genera una cantidad de información abrumadora. Es expresada en mensajes de 140 caracteres conocidos como tweets. Twitter permite buscar tanto tweets de usuarios concretos como tweets que contengan términos específicos, pero no permite la búsqueda temática, es decir no permite agrupar los mensajes bajo epígrafes generales. Con este TFG hemos querido plantear una solución que facilite la búsqueda temática en Twitter. Nuestra propuesta es capaz de descargar tweets y agruparlos bajo diferentes categorías dándole una utilidad a los tweets más allá de su propio contenido, pudiendo realizar búsquedas por temáticas, facilitando la experiencia al usuario. Como caso de uso, nos centramos en el caso de búsqueda temática sobre una ciudad. Para la clasificación en categorías, es necesario realizar primero una categorización de forma manual para que posteriormente mediante técnicas de aprendizaje automático se realice una clasificación de forma automática. Para la clasificación automática, hemos utilizado la técnica de aprendizaje supervisado basada en el Teorema de Bayes, que deduce mediante entrenamiento y validación a qué categoría puede pertenecer un tweet. El usuario finalmente podrá filtrar toda esta información en función de las categorías creadas, fechas y palabras clave que contenga el tweet

Lunar impact flashes from Geminids, analysis of luminous efficiencies and the flux of large meteoroids on Earth

We analyze lunar impact flashes recorded by our team during runs in December 2007, 2011, 2013 and 2014. In total, 12 impact flashes with magnitudes ranging between 7.1 and 9.3 in V band were identified. From these, 9 events could be linked to the Geminid stream. Using these observations the ratio of luminous energy emitted in the flashes with respect to the kinetic energy of the impactors for meteoroids of the Geminid stream is estimated. By making use of the known Geminids meteoroid flux on Earth we found this ratio to be 2.1x10$^{-3}$ on average. We compare this luminous efficiency with other estimations derived in the past for other meteoroid streams and also compare it with other estimations that we present here for the first time by making use of crater diameter measurements. We think that the luminous efficiency has to be revised downward, not upward, at least for sporadic impacts. This implies an increase in the influx of kilogram-sized and larger bodies on Earth that has been derived thus far through the lunar impact flash monitoring technique