Remote detection of fumarolic gas chemistry at Vulcano, Italy, using an FT-IR spectral radiometer

An infrared absorption spectroscopy remote sensing technique was used to determine the S02/HCl ratio in fumarolic plumes at Vulcano, Italy. The measurements were made from the southern crater rim of Fossa Grande Crater, about 400 m from the fumarolic area in the crater. Infrared absorption spectra of HCl and SO, were observed for four fumaroles a few tens of metres apart using the hot fumarolic surface as an infrared light source. The measured S02/HCl ratios in the FA, F47, FW and lower parti of the F21 fumaroles were 4.5-5.4, 3.5, 9.5-11.2 and 5.8 respectively. The S02/HCl ratio of the FA fumarole was higher than that of the gas collected directly in the fumarolic vent (S02/HCl ratio = 2.9), and was closer to the S~,,,,,,/HCl ratio (= 4.6) of the collected gas. Our results show that the SO,/HCl ratios of two fumaroles only a few tens of metres apart exhibits differences of about twofold. This suggests that this remote monitoring technique is capable of detecting spatial distribution in the S02/HCl ratios of volcanic plumes. Because temporal variations in S/Cl ratios can provide precursory signals for volcanic eruptions [l-31, this remote sensing technique can used efficiently for evaluation of volcanic activity

Blue asymmetries of Balmer lines during M-dwarf flares investigated with multi-wavelength observations

Stars and planetary system

EARTHQUAKE PREDICTION IN THE AREA OF N. EVIA ON THE BASIS OF GROUNDWATER RADON CONCENTRATION CHANGES

Σημαντικές μεταβολές της συγκέντρωσης του Ραδονίου στα υπόγεια νερά, παρατηρήθηκαν στις 29/7/2003, στο σταθμό μέτρησης των Καμμένων Βούρλων. Οι μεταβολές αυτές είναι αποτέλεσμα των προσεισμικών τάσεων που αναπτύσσονται και έχουν σαν αποτέλεσμα τον προσωρινό εμπλουτισμό του υδροφόρου ορίζοντα σε ραδόνιο Για την ύπαρξη των μεταβολών αυτών ενημερώθηκε αμέσως ο ΟΑΣΠ. Στις 3/8/2003 καταγράφηκε, σε διάστημα μερικών ωρών ένας σημαντικός αριθμός σεισμικών δονήσεων στην Βόρεια Εύβοια. Τα επίκεντρα των σεισμικών αυτών δονήσεων τοποθετούνται στην νοητή γραμμή μεταξύ του επίκεντρου του μεγάλου σεισμού της Σκύρου και της θέσης του σταθμού μέτρησης Ραδονίου στα Καμμένα Βούρλα. Δηλαδή στην προέκταση του ρήγματος του Βορείου Αιγαίου. Στις 23/1/2003, παρουσιάστηκαν στον ίδιο σταθμό μέτρησης 3 σημαντικές μεταβολές του Ραδονίου. Ειδοποιήθηκε ο ΟΑΣΠ για επικείμενη σεισμική δραστηριότητα στη Βόρεια Εύβοια. Στις 29 Ιανουαρίου έγιναν πράγματι τρεις σεισμικές δονήσεις με το επίκεντρο τους να ευρίσκεται πολύ κοντά στο σταθμό μέτρησης των Καμμένων Βούρλων. Στις 2/2/2003, παρουσιάστηκε νέα σημαντική μεταβολή του Ραδονίου στον Σταθμό των Καμμένων Βούρλων που επίσης συνοδεύτηκε από σεισμική δόνηση (7/2/2003) με το ίδιο επίκεντρο. Στις 12/2/2003 σε επιστολή που απευθύναμε στην διοίκηση του ΟΑΣΠ, αναφερόταν η έναρξη νέας μεταβολής του Ραδονίου που επίσης κατέληξε σε σεισμική δόνηση με επίκεντρο στην Β. Εύβοια απέναντι από τον σταθμό των Καμμένων Βούρλων. Οι μεταβολές που καταγράφονται στο σύστημα μέτρησης Ραδονίου που είναι τοποθετημένο στην περιοχή των Καμμένων Βούρλων, προηγούνται κατά 4-6 ημέρες, σεισμικών δονήσεων που συνδέονται με την προέκταση του ρήγματος του Β. Αιγαίου προς την Στερεά Ελλάδα και έχουν το επίκεντρο τους στην Β. Εύβοια. Η μέθοδος φαίνεται ότι θα αποτελέσει ένα σημαντικό εργαλείο στην βραχυπρόθεσμη πρόγνωση σεισμικών δονήσεων, σε τοπικό επίπεδο.Significant changes in the groundwater radon concentration, were observed on the 29/7/2003, at Kammena Vourla. The radon concentration changes can be attributed to the temporary enrichment of the groundwater by radon from the surrounding rocks due to the action of stress release or stress accumulation prior an earthquake. EPPO was immediately informed for the existence of these changes. On the 3/8/2003, a significant number of earthquakes in Northern Evia were recorded in an interval of a few hours. The epicentres of the earthquakes were located in the conceivable line between the epicentre of the strong earthquake of Skyros island (July 2001) and the site of the station of radon measurement at Kammena Vourla, on the extension of the Northern Aegean fault. In the 23/1/2003, in the same station, 3 significant changes of radon concentration were measured EPPO was immediately informed for impending seismic activity in Northern Evia. On the 29th of January three earthquakes were recorded. Their epicentres were located in N. Evia, close to the radon measurement, station. On the 2/2/2003, a new significant radon change occurred at Kammena Vourla followed by an earthquake (7/2/2003). In the 12/2/2003 in a letter that we addressed to the EPPO administration, the beginning of a new radon change was reported which also led to an earthquake with the same epicentre. The changes that are recorded in the system of radon measurement of Kammena Vourla are precursors of earthquakes, related to the extension of the N. Aegean fault towards the Sterea Hellas and have their epicentre in N. Evia. It seems that the method can be an important tool for local, short term earthquake prediction

Fractal Reconnection in Solar and Stellar Environments

Recent space based observations of the Sun revealed that magnetic reconnection is ubiquitous in the solar atmosphere, ranging from small scale reconnection (observed as nanoflares) to large scale one (observed as long duration flares or giant arcades). Often the magnetic reconnection events are associated with mass ejections or jets, which seem to be closely related to multiple plasmoid ejections from fractal current sheet. The bursty radio and hard X-ray emissions from flares also suggest the fractal reconnection and associated particle acceleration. We shall discuss recent observations and theories related to the plasmoid-induced-reconnection and the fractal reconnection in solar flares, and their implication to reconnection physics and particle acceleration. Recent findings of many superflares on solar type stars that has extended the applicability of the fractal reconnection model of solar flares to much a wider parameter space suitable for stellar flares are also discussed.Comment: Invited chapter to appear in "Magnetic Reconnection: Concepts and Applications", Springer-Verlag, W. D. Gonzalez and E. N. Parker, eds. (2016), 33 pages, 18 figure

Candidate Water Vapor Lines to Locate the H2O Snowline through High-dispersion Spectroscopic Observations. III. Submillimeter H2 16O and H2 18O Lines

In this paper, we extend the results presented in our former papers on using ortho-H216O line profiles to constrain the location of the H2O snowline in T Tauri and Herbig Ae disks, to include submillimeter para-H216O and ortho- and para-H218O lines. Since the number densities of the ortho- and para-H218O molecules are about 560 times smaller than their 16O analogs, they trace deeper into the disk than the ortho-H216O lines (down to z = 0, i.e., the midplane). Thus these H218O lines are potentially better probes of the position of the H2O snowline at the disk midplane, depending on the dust optical depth. The values of the Einstein A coefficients of submillimeter candidate water lines tend to be lower (typically <10‑4 s‑1) than infrared candidate water lines. Thus in the submillimeter candidate water line cases, the local intensity from the outer optically thin region in the disk is around 104 times smaller than that in the infrared candidate water line cases. Therefore, in the submillimeter lines, especially H218O and para-H216O lines with relatively lower upper state energies (∼a few 100 K) can also locate the position of the H2O snowline. We also investigate the possibility of future observations with ALMA to identify the position of the water snowline. There are several candidate water lines that trace the hot water gas inside the H2O snowline in ALMA Bands 5–10

Life Beyond the Solar System: Space Weather and Its Impact on Habitable Worlds

The search of life in the Universe is a fundamental problem of astrobiology and a major priority for NASA. A key area of major progress since the NASA Astrobiology Strategy 2015 (NAS15) has been a shift from the exoplanet discovery phase to a phase of characterization and modeling of the physics and chemistry of exoplanetary atmospheres, and the development of observational strategies for the search for life in the Universe by combining expertise from four NASA science disciplines including heliophysics, astrophysics, planetary science and Earth science. The NASA Nexus for Exoplanetary System Science (NExSS) has provided an efficient environment for such interdisciplinary studies. Solar flares, coronal mass ejections and solar energetic particles produce disturbances in interplanetary space collectively referred to as space weather, which interacts with the Earth upper atmosphere and causes dramatic impact on space and ground-based technological systems. Exoplanets within close in habitable zones around M dwarfs and other active stars are exposed to extreme ionizing radiation fluxes, thus making exoplanetary space weather (ESW) effects a crucial factor of habitability. In this paper, we describe the recent developments and provide recommendations in this interdisciplinary effort with the focus on the impacts of ESW on habitability, and the prospects for future progress in searching for signs of life in the Universe as the outcome of the NExSS workshop held in Nov 29 - Dec 2, 2016, New Orleans, LA. This is one of five Life Beyond the Solar System white papers submitted by NExSS to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Universe.Comment: 5 pages, the white paper was submitted to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Univers

Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets

The current progress in the detection of terrestrial type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favorable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of astrospheric, atmospheric and surface environments of exoplanets in habitable zones around G-K-M dwarfs including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles, and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favorable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro) physical, chemical, and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the habitable zone to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.Comment: 206 pages, 24 figures, 1 table; Review paper. International Journal of Astrobiology (2019

Editing site analysis in a gymnosperm mitochondrial genome reveals similarities with angiosperm mitochondrial genomes

Sequence analysis of organelle genomes and comprehensive analysis of C-to-U editing sites from flowering and non-flowering plants have provided extensive sequence information from diverse taxa. This study includes the first comprehensive analysis of RNA editing sites from a gymnosperm mitochondrial genome, and utilizes informatics analyses to determine conserved features in the RNA sequence context around editing sites. We have identified 565 editing sites in 21 full-length and 4 partial cDNAs of the 39 protein-coding genes identified from the mitochondrial genome of Cycas taitungensis. The information profiles and RNA sequence context of C-to-U editing sites in the Cycas genome exhibit similarity in the immediate flanking nucleotides. Relative entropy analyses indicate that similar regions in the 5′ flanking 20 nucleotides have information content compared to angiosperm mitochondrial genomes. These results suggest that evolutionary constraints exist on the nucleotide sequences immediately adjacent to C-to-U editing sites, and similar regions are utilized in editing site recognition

Distant sequences determine 5′ end formation of cox3 transcripts in Arabidopsis thaliana ecotype C24

The genomic environments and the transcripts of the mitochondrial cox3 gene are investigated in three Arabidopsis thaliana ecotypes. While the proximate 5′ sequences up to nucleotide position −584, the coding regions and the 3′ flanking regions are identical in Columbia (Col), C24 and Landsberg erecta (Ler), genomic variation is detected in regions further upstream. In the mitochondrial DNA of Col, a 1790 bp fragment flanked by a nonanucleotide direct repeat is present beyond position −584 with respect to the ATG. While in Ler only part of this insertion is conserved, this sequence is completely absent in C24, except for a single copy of the nonanucleotide direct repeat. Northern hybridization reveals identical major transcripts in the three ecotypes, but identifies an additional abundant 60 nt larger mRNA species in C24. The extremities of the most abundant mRNA species are identical in the three ecotypes. In C24, an extra major 5′ end is abundant. This terminus and the other major 5′ ends are located in identical sequence regions. Inspection of Atcox3 transcripts in C24/Col hybrids revealed a female inheritance of the mRNA species with the extra 5′ terminus. Thus, a mitochondrially encoded factor determines the generation of an extra 5′ mRNA end