Large impact cratering during lunar magma ocean solidification

The lunar cratering record is used to constrain the bombardment history of both the Earth and the Moon. However, it is suggested from different perspectives, including impact crater dating, asteroid dynamics, lunar samples, impact basin-forming simulations, and lunar evolution modelling, that the Moon could be missing evidence of its earliest cratering record. Here we report that impact basins formed during the lunar magma ocean solidification should have produced different crater morphologies in comparison to later epochs. A low viscosity layer, mimicking a melt layer, between the crust and mantle could cause the entire impact basin size range to be susceptible to immediate and extreme crustal relaxation forming almost unidentifiable topographic and crustal thickness signatures. Lunar basins formed while the lunar magma ocean was still solidifying may escape detection, which is agreeing with studies that suggest a higher impact flux than previously thought in the earliest epoch of Earth-Moon evolution.

Artificial neural network classification of asteroids in the M1:2 mean-motion resonance with Mars

ABSTRACT Artificial neural networks (ANNs) have been successfully used in the last years to identify patterns in astronomical images. The use of ANN in the field of asteroid dynamics has been, however, so far somewhat limited. In this work, we used for the first time ANN for the purpose of automatically identifying the behaviour of asteroid orbits affected by the M1:2 mean-motion resonance with Mars. Our model was able to perform well above 85 per cent levels for identifying images of asteroid resonant arguments in term of standard metrics like accuracy, precision, and recall, allowing to identify the orbital type of all numbered asteroids in the region. Using supervised machine learning methods, optimized through the use of genetic algorithms, we also predicted the orbital status of all multi-opposition asteroids in the area. We confirm that the M1:2 resonance mainly affects the orbits of the Massalia, Nysa, and Vesta asteroid families.

Exploring the Celestial Sphere with the Telescope and Computational Analysis of the Images

One of the modern methods of teaching astronomy is the Investigation, one of Inquiry Based Learning methods, used as an educational method in the elaboration of extracurricular projects, as an example for the students of the Faculty of Sciences, from University of Craiova, Romania. The paper presents a join approach to research in Astronomy and Computer Science, using Scientific Inquiry methods and Computer programming skills to study the asteroid dynamics in the Solar System. Starting with the image analysis with the software Astrometrica, necessary for the determination of moving objects astrometry in astronomical images, the students developed, under supervision of the author, some software tools oriented to fast identification and classification of the founded asteroids. Theirs tools where tested on real astronomy data, namely raw images, obtained with the INT telescope in La Palma, the Canary Islands. Following this methodological experiment the students arrive to develop within a short time advanced practical skills for research in Computational Astronomy, increasing in the same time theirs knowledge as Web programmers.