Spectroscopic and photometric characterization of primitive asteroid collisional families

The study of near-Earth asteroids (NEAs) is very important, due to three main reasons. First, they pose an impact risk for Earth, and damage produced by a possible collision will depend on the speed of the impact, the size of the object, and its composition. Second, given their proximity, they are easy access targets for the visit of space missions. And third, these objects are possible sources of in-situ resources for future space missions (or ISRU, for in-situ resource utilization), that would enable the affordable establishment of extraterrestrial exploration and operations by minimizing the materials carried from Earth. Space missions OSIRIS-REx (NASA, launched on 2016) and Hayabusa 2 (JAXA, launched on 2014) will visit two primitive NEAs: (101955) Bennu and (162173) Ryugu, respectively. The main goal of these missions is to collect a sample of surface material from these NEAs and bring it back to Earth for analysis. These asteroids are considered “primitive” due to their low albedo and carbonaceous composition, inferred from their spectral characteristics, similar to those of the carbonaceous chondrites (the most primitive meteorites, that have undergone almost no evolution since the early stages of the Solar System). Several dynamic studies suggest that these NEAs originate in the inner part of the main asteroid belt, within the low-albedo low-inclination families (i<8º): the Polana–Eulalia complex, and the Erigone, Sulamitis, and Clarissa families. There is a significant lack of compositional information for asteroids in the primitive families in the main belt, and therefore any spectroscopic or photometric survey in this sense will be a major contribution. The link between primitive NEAs and primitive families is suggestive but not definitive, so it needs confirmation and detailed study. The main objective of this thesis work is to study and characterize the most likely origin of (101955) Bennu and (162173) Ryugu, targets of the sample-return space missions OSIRIS-REx and Hayabusa 2, as well as to provide information about other possible sources of primitive asteroids throughout the main belt. This thesis work is a direct follow-up of the studies on the Polana–Eulalia complex, the low-albedo (pv < 0.1) part of the Nysa family, located in the inner region of the main belt. This initial study showed that the Polana–Eulalia complex is mainly composed of C- and B-type asteroids (primitive objects), presenting spectral homogeneity. This thesis is a compendium of three papers, published in the Astronomy & Astrophyisics journal. Two different approaches to the analysis have been used: (1) through visible spectroscopy (0.5–0.9 μm), using data obtained with the Gran Telescopio Canarias (GTC), we analayzed three asteroid families located in the inner region of the main belt (Erigone, Sulamitis, and Clarissa); and (2) through near-infrared photometry (0.9–2.4 μm) we analyzed the asteroid families observed in the MOVIS (Moving Objects from VISTA) catalog. The results regarding the Erigone collisional family showed that, approximately, 87% of the observed objects have typical primitive asteroid spectra, consistent with the spectrum of (163) Erigone, the parent body. In addition, we found a significant percentage of family members (50%) with spectral features related to the presence of hydrated minerals on their surfaces. After the analysis of the Sulamitis and Clarissa families, the smallest of the possible NEAs sources, we found that about 60% of the observed asteroids in the Sulamitis family show signs of aqueous alteration on their surfaces, while almost all of the objects in the Clarissa family do not show any evidences of hydration. Also, according to the visible spectra obtained for the members of the primitive families in the inner main belt studied so far, we can differentiate between two groups: the Polana-like group (Polana and Clarissa), which presents homogeneous, featureless spectra in a continuum of slopes from blue to moderately red, and no aqueous alteration, and the Erigone-like group (Erigone and Sulamitis), showing a spectral diversity among primitive taxonomic classes and a majority of spectra with the aqueous alteration band. The study on the near-infrared data of the MOVIS catalog allowed us to characterize 43 families through the whole main belt: 15 primitive, 19 rocky, and 9 that were defined as “mixtures” of the proposed theoretical compositions. The results of this thesis constitute one of the most significant contributions that have been made up to now to the compositional study of primitive asteroid families. Besides, the investigations about the most probable origins of NEAs (101955) Bennu and (162173) Ryugu will be of great help to test the dynamical models which explain the asteroidal transport routes from the main belt to the near-Earth space. Our results will be specially relevant for the interpretation of the images and spectra obtained in situ by the spacecrafts OSIRIS-REx and Hayabusa 2 during their encounters with their targets, placing the mission’s data within the big picture of the evolutionary history of the Solar System

Un modelo técnico, económico y social para mejorar la productividad de los berries en la sierra del Perú

Publicación a texto completo no autorizada por el autorIdentifica y adecúa la siembra y producción de productos saludables y/o antioxidantes con demanda en el mercado internacional en la sierra del Perú. Estableciendo su viabilidad del cultivo identificado estableciendo un modelo sistémico. Específicamente, realiza un esbozo de la situación actual de los berries en el Perú y también se presentan las características del sector agrario de Ancash. Se plantea también la factibilidad de iniciar un negocio en este rubro cuya inversión inicial es de s/.686,449.27 por 10 hectáreas de sembrío, cuya extensión de tierra deja 21 toneladas en total.Tesi

Dust environment of active asteroids P/2019 A4 (PANSTARRS) and P/2021 A5 (PANSTARRS)

We report on the characterisation of the dust activity and dynamical evolution of two faint active asteroids, P/2019 A4, and P/2021 A5, observed with the 10.4m GTC using both imaging and spectroscopy. Asteroid P/2019 A4 activity is found to be linked to an impulsive event occurring some $\pm$10 days around perihelion, probably due to a collision or a rotational disruption. Its orbit is stable over 100 Myr timescales. Dust tail models reveal a short-term burst producing (2.0$\pm$0.7)$\times$10$^6$ kg of dust for maximum particle radius rmax=1 cm. The spectrum of P/2019 A4 is featureless, and slightly redder than the Sun. P/2021 A5 was active $\sim$50 days after perihelion, lasting $\sim$5 to $\sim$60 days, and ejecting (8$\pm$2)$\times$10$^6$ kg of dust for rmax=1 cm. The orbital simulations show that a few percent of dynamical clones of P/2021 A5 are unstable on 20-50 Myr timescales. Thus, P/2021 A5 might be an implanted object from the JFC region or beyond. These facts point to water ice sublimation as the activation mechanism. This object also displays a featureless spectrum, but slightly bluer than the Sun. Nuclei sizes are estimated in the few hundred meters range for both asteroids. Particle ejection speeds ($\sim$0.2 m/s) are consistent with escape speeds from those small-sized objects.Comment: Accepted by MNRAS (June 24th, 2021

Compositional study of asteroids in the Erigone collisional family using visible spectroscopy at the 10.4 m GTC

Two primitive near Earth asteroids, (101955) Bennu and (162173) Ryugu, will be visited by a spacecraft with the aim of returning samples back to Earth. Since these objects are believed to originate in the inner main belt primitive collisional families (Erigone, Polana, Clarissa, and Sulamitis) or in the background of asteroids outside these families, the characterization of these primitive populations will enhance the scientific return of the missions. The main goal of this work is to shed light on the composition of the Erigone collisional family by means of visible spectroscopy. Asteroid (163) Erigone has been classified as a primitive object, and we expect the members of this family to be consistent with the spectral type of the parent body. We have obtained visible spectra (0.5 to 0.9 microns) for 101 members of the Erigone family, using the OSIRIS instrument at the 10.4 m Gran Telescopio Canarias. We found that 87 percent of the objects have typically primitive visible spectra consistent with that of (163) Erigone. In addition, we found that a significant fraction of these objects (approximately 50 percent) present evidence of aqueous alteration

In-depth proteomics characterization of ∆Np73 effectors identifies key proteins with diagnostic potential implicated in lymphangiogenesis, vasculogenesis and metastasis in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related death worldwide. Alterations in proteins of the p53-family are a common event in CRC. ΔNp73, a p53-family member, shows oncogenic properties and its effectors are largely unknown. We performed an in-depth proteomics characterization of transcriptional control by ∆Np73 of the secretome of human colon cancer cells and validated its clinical potential. The secretome was analyzed using high-density antibody microarrays and stable isotopic metabolic labeling. Validation was performed by semiquantitative PCR, ELISA, dot-blot and western blot analysis. Evaluation of selected effectors was carried out using 60 plasma samples from CRC patients, individuals carrying premalignant colorectal lesions and colonoscopy-negative controls. In total, 51 dysregulated proteins were observed showing at least 1.5-foldchange in expression. We found an important association between the overexpression of ∆Np73 and effectors related to lymphangiogenesis, vasculogenesis and metastasis, such as brain-derived neurotrophic factor (BDNF) and the putative aminoacyl tRNA synthase complex-interacting multifunctional protein 1 (EMAP-II)-vascular endothelial growth factor C-vascular endothelial growth factor receptor 3 axis. We further demonstrated the usefulness of BDNF as a potential CRC biomarker able to discriminate between CRC patients and premalignant individuals from controls with high sensitivity and specificity.This study has been funded by Instituto de Salud Carlos III (ISCIII) through the project “PI18/00473” and co-funded by the European Union (FEDER funds) and Cátedra UAM-Roche en Medicina de Innovación to GD, and the Ramón y Cajal Programme of the MINECO, PI17CIII/00045 and PI20CIII/00019 research projects from AES-ISCIII to RB. MG-A and JR-C were supported by contracts of the Programa Operativo de Empleo Juvenil y la Iniciativa de Empleo Juvenil (YEI) with the participation of the Consejería de Educación, Juventud y Deporte de la Comunidad de Madrid y del Fondo Social Europeo. AM-C FPU predoctoral contract is supported by the MECD. GS-F is a recipient of a predoctoral contract (grant num-ber 1193818N) supported by The Flanders Research Foundation (FWO).S

J-PLUS: A first glimpse at spectrophotometry of asteroids -- The MOOJa catalog

Context: The Javalambre Photometric Local Universe Survey (J-PLUS) is an observational campaign that aims to obtain photometry in 12 ultraviolet-visible filters (0.3-1 {\mu}m) of approximately 8 500 deg{^2} of the sky observable from Javalambre (Teruel, Spain). Due to its characteristics and strategy of observation, this survey will let us analyze a great number of Solar System small bodies, with improved spectrophotometric resolution with respect to previous large-area photometric surveys in optical wavelengths. Aims: The main goal of this work is to present here the first catalog of magnitudes and colors of minor bodies of the Solar System compiled using the first data release (DR1) of the J-PLUS observational campaign: the Moving Objects Observed from Javalambre (MOOJa) catalog. Methods: Using the compiled photometric data we obtained very-low-resolution reflectance (photospectra) spectra of the asteroids. We first used a {\sigma}-clipping algorithm in order to remove outliers and clean the data. We then devised a method to select the optimal solar colors in the J-PLUS photometric system. These solar colors were computed using two different approaches: on one hand, we used different spectra of the Sun, convolved with the filter transmissions of the J-PLUS system, and on the other, we selected a group of solar-type stars in the J-PLUS DR1, according to their computed stellar parameters. Finally, we used the solar colors to obtain the reflectance spectra of the asteroids. Results: We present photometric data in the J-PLUS filters for a total of 3 122 minor bodies (3 666 before outlier removal), and we discuss the main issues of the data, as well as some guidelines to solve the

Apophis planetary defense campaign

We describe results of a planetary defense exercise conducted during the close approach to Earth by the near-Earth asteroid (99942) Apophis during 2020 December–2021 March. The planetary defense community has been conducting observational campaigns since 2017 to test the operational readiness of the global planetary defense capabilities. These community-led global exercises were carried out with the support of NASA's Planetary Defense Coordination Office and the International Asteroid Warning Network. The Apophis campaign is the third in our series of planetary defense exercises. The goal of this campaign was to recover, track, and characterize Apophis as a potential impactor to exercise the planetary defense system including observations, hypothetical risk assessment and risk prediction, and hazard communication. Based on the campaign results, we present lessons learned about our ability to observe and model a potential impactor. Data products derived from astrometric observations were available for inclusion in our risk assessment model almost immediately, allowing real-time updates to the impact probability calculation and possible impact locations. An early NEOWISE diameter measurement provided a significant improvement in the uncertainty on the range of hypothetical impact outcomes. The availability of different characterization methods such as photometry, spectroscopy, and radar provided robustness to our ability to assess the potential impact risk