Explore the vast range of titles available.

We evaluated agreement among trained emergency physicians assessing the degree of B-line presence on bedside ultrasound in patients presenting to the emergency department (ED) with acute undifferentiated dyspnea. We also determined which thoracic zones offered the highest level of interobserver reliability for sonographic B-line assessment. We evaluated a prospective convenience sample of adult patients presenting with dyspnea to an academic ED. Two consecutive bedside lung ultrasounds were performed on 91 patients by a pair of physician-sonographers. The lung ultrasounds were structured 10-zone thoracic sonograms, documented as videos. Sonographer pairs were expert/expert (>100 lung ultrasounds performed) or expert/novice pairs (novices performed 5 supervised examinations after structured training) and blinded to clinical data. Sonographers reported B-line concentration with 3 assessment methods: (1) normal (<3 B-lines) or abnormal (≥3 B-lines); (2) ordinal (normal, mild, moderate, or severe), and (3) counting B-lines (0-10; >10) in each zone. All statistical analyses were performed using SPSS version 18.0 (Chicago, IL) and Stata 12.1 (College Station, TX). We evaluated interrater and intrarater agreement using Intraclass correlation coefficients (ICCs). The right and left anterior/superior lung zones showed substantial agreement in all assessment methods and demonstrated best overall agreement (ICC for right: counting, ordinal, and normal/abnormal, 0.811 [0.714-0.875], 0.875 [0.810-0.917], and 0.729 [0.590-0.821], respectively). Furthermore, both expert/expert pairs and expert/novice pairs showed substantial agreement in the right and left anterior/superior thoracic zones (expert/expert, 0.904 and 0.777, respectively; expert/novice, 0.862, and 0.834, respectively). Second best agreement was found for the lateral/superior lung zones (right: counting, ordinal, and normal/abnormal, 0.744 [0.612-0.831], 0.686 [0.524-0.792], and 0.639 [0.453-0.761], respectively; and ICC left: counting, ordinal, and normal/abnormal, 0.671 [0.501-0.782], 0.615 [0.417-0.746], and 0.720 [0.577-0.815], respectively). When comparing agreement to distinguish “normal vs abnormal” B-line findings, our results showed significant agreement in all zones with the exception of the right and left inferior/lateral lung fields and left posterior lung. Reinterpretation by 2 experts of all their own randomized video clips at a later date showed agreement of 0.697 (n = 733 zones) and 0.647 (n = 266) zones for ordinal assessment of B-line concentration. Interrater agreement was best in the anterior/superior thoracic zones followed by the lateral/superior zones for both expert/expert and expert/novice pairs. Agreement in the lateral/inferior lung zones was overall inferior. Intrarater agreement was highest at extreme high or low numbers of B-lines.

C/1910 A1 was one of the Great Comets of the twentieth century. Although it was widely observed from the Northern Hemisphere, it was first discovered by observers south of the Equator. The comet arrived just months before the widely anticipated apparition of Comet 1P/Halley and was significantly more spectacular. As a result, the two comets were confused, and many who, in later years, talked about how prominent Comet 1P/Halley was in 1910 were often remembering C/1910 A1. In this paper, we present the results of a detailed search through historical records and media publications in Aotearoa / New Zealand, to investigate how extensively C/1910 A1 was observed from New Zealand. We compare our results with observations reported for Comet 1P/Halley later in 1910, finding that surprisingly few observations of C/1910 A1 were made by New Zealand observers. We discuss cases where the comet was misidentified as being an early sighting of 1P/Halley and compare the observations made in New Zealand with international observations/records/accounts. We find that, although the Great January Comet of 1910 was observed from New Zealand, it was witnessed by few compared to other parts of the world, meaning that the apparition of C/1910 A1 was something of a missed opportunity for New Zealand astronomers.

Written by a well-known and experienced amateur astronomer, this is a practical primer for all aspiring observers of the planets and other Solar System objects. Whether you are a beginner or more advanced astronomer, you will find all you need in this book to help develop your knowledge and skills and move on to the next level of observing. This up-to-date, self-contained guide provides a detailed and wide-ranging background to Solar System astronomy, along with extensive practical advice and resources. Topics covered include: traditional visual observing techniques using telescopes and ancillary equipment; how to go about imaging astronomical bodies; how to conduct measurements and research of scientifically useful quality; the latest observing and imaging techniques. Whether your interests lie in observing aurorae, meteors, the Sun, the Moon, asteroids, comets, or any of the major planets, you will find all you need here to help you get started.

We propose a new formal definition of discovery for a Solar System object. It is based on an objective and mathematically rigorous algorithm to assess when a set of observations is enough to constitute a discovery. When this definition is satisfied, in almost all cases the orbit is defined well enough to establish the nature of the object discovered (Main Belt vs. Near Earth Asteroid, Trans-Neptunian vs. long period comet). The frequency of occurrence of exceptions is estimated by a set of numerical experiments.The availability of a non-subjective definition of discovery allows some rules to be adopted for the assignment of discovery credit with a minimum risk of dispute. Such rules should be fair, encourage good practice by the observers and acknowledge the contribution of the orbit computers providing the identifications and the orbits, as well as the one of all the contributing observers.

A variety of independent methods have been used to estimate the size of the nucleus of comet Hale-Bopp. Several groups have analyzed optical and infrared images of the comet and claim to detect the signature of the nucleus, despite the presence of a strong coma. A detection of the nucleus was also claimed during mm- and cm-wave observations of Hale-Bopp shortly before perihelion. A team of observers detected the occultation of a star by the nucleus of Hale-Bopp in October 1996. The maximum observed gas production rate of the comet near perihelion can be used to place a lower limit on the size of the nucleus. This paper critically reviews the many different methods used to constrain the size of Hale-Bopp's nucleus. All of the techniques are affected by systematic errors that can be difficult to quantify precisely. Nevertheless, the available evidence strongly suggests that the nucleus of Hale-Bopp has an effective radius of at least 15 km and is probably in the range 20–35 km. Thus, the prodigious gas and production rates from this comet are naturally explained by its unusually large size.

The long-term brightness evolution of the great comet C/1995 O1 (Hale-Bopp) presented a remarkable opportunity to study the behavior of its coma over four years. We used approximately 2200 total visual magnitudes published in the International Comet Quarterly taken from 17 observers during the period of 1995 July - 1999 September to create a secular lightcurve. In order to account for observer differences, we present a novel algorithm to reduce scatter and increase precision in a lightcurve compiled from many sources. It is implemented in a publicly available code, ICQSPLITTER. This code addresses the differences among observers by using a self-consistent statistical approach, leading to a sharper lightcurve, and improving the precision of the measured slopes. To first order, the comet's lightcurve approximately follows a r\\(^{-4}\\) response for both pre- and post-perihelion distances. Interestingly, the pre-perihelion data are better fit with a fifth-order polynomial with inflection points at 4.0, 2.6, 2.1 and 1.1 au. We analyze these specific regions and find that they are associated with physical phenomena in the comet's evolution. Contrary to other reports, the lightcurve shows no evidence for the comet having been in outburst at discovery. Afrho values derived from the visual lightcurve data are consistent with a r\\(^{-1.5}\\) dependence on heliocentric distance, which is similar in shape to those derived from spectroscopy and narrow-band photometry. We present correlation equations for visual magnitudes and CO and H2O production rates, which are consistent with the pre-perihelion visual magnitudes increasing almost entirely due to CO outgassing until a heliocentric distance of about 2.6 - 3.0 au. We also present two correlation equations that should prove highly useful for observation planning and data analysis, and can be generalized to be applicable to other comets.

People have probably been watching the sky since the beginning of human history. Observers in pre-telescopic ages recorded anomalous events and these astronomical records in the historical documents provide uniquely valuable information for modern scientists. Records with drawings are particularly useful, as the verbal expressions recorded by pre-telescopic observers, who did not know the physical nature of the phenomena, are often ambiguous. However, drawings for specific datable events in the historical documents are much fewer than the verbal records. Therefore, in this paper, we show the possible earliest drawings of datable auroras and a two-tail comet in a manuscript of the Chronicle of Zūqnīn, a Syriac chronicle up to 775/776 CE to interpret their nature. They provide not only the historical facts in the realm around Amida but also information about low-latitude aurora observations due to extreme space weather events and the existence of sun-grazing comets.

The nucleus of 51P/Harrington suffered a majorsplitting event in Autumn 2001discovered by amateur José Manteca.The light curve and separation of thefragments is examined based on data fromthe observers collaborating in the Spanishlanguage ``Cometas_Obs'' mailing list, includinga number of pre-announcement observations. Thereis some uncertainty in the epoch of the initiationof the split. Some evidence favours an earlierinitiation than September 2001.

We present the results of a global coma morphology campaign for comet C/2012 S1 (ISON), which was organized to involve both professional and amateur observers. In response to the campaign, many hundreds of images, from nearly two dozen groups were collected. Images were taken primarily in the continuum, which help to characterize the behavior of dust in the coma of comet ISON. The campaign received images from January 12 through November 22, 2013 (an interval over which the heliocentric distance decreased from 5.1 AU to 0.35 AU), allowing monitoring of the long-term evolution of coma morphology during the pre-perihelion leg of comet ISON. Data were contributed by observers spread around the world, resulting in particularly good temporal coverage during November when comet ISON was brightest but its visibility was limited from any one location due to the small solar elongation. We analyze the northwestern sunward continuum coma feature observed in comet ISON during the first half of 2013, finding that it was likely present from at least February through May and did not show variations on diurnal time scales. From these images we constrain the grain velocities to ~10 m/s, and we find that the grains spent 2-4 weeks in the sunward side prior to merging with the dust tail. We present a rationale for the lack of continuum coma features from September until mid-November 2013, determining that if the feature from the first half of 2013 was present, it was likely too small to be clearly detected. We also analyze the continuum coma morphology observed subsequent to the November 12 outburst, and constrain the first appearance of new features in the continuum to later than November 13.99 UT.