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A Survival Guide to the Misinformation Age: Scientific Habits of Mind, David J. Helfand, Columbia U. Press, 2016. $29.95 (344pp.). ISBN 978-0-231-16872-4 Buy at AmazonScience is one of several human inventions—like farming, writing, and mathematics—that has substantially enhanced our quality of life, improved our health and longevity, and led to an understanding of the universe. David Helfand’s new book A Survival Guide to the Misinformation Age: Scientific Habits of Mind is a primer on the methods of science that make it so powerful. It is also a paean to the expansion of experience that scientific thinking provides those willing to learn a few tools of the trade.How I wish everyone would read, appreciate, and follow its guidance. Our world would surely be a much better place if more people implemented the “habits of mind” that Helfand details. Our politicians would behave differently, since their statements would be judged and assessed rationally instead of through emotional resonance. Outrageous websites claiming alien visitations, miracle cures, or unbeatable investment opportunities would see no traffic, as their claims would be seen as impossible or flawed after even a cursory analysis. Policy discussions would begin with a shared sense of the fundamental problems to be overcome instead of arguments about whose “facts” are correct.How very different from where we find ourselves today, when textbooks explaining evolution face seemingly never-ending challenges in school districts across the US; when large swaths of the populace question the reality of carbon dioxide–induced climate change and even whether the amount of CO2 is increasing; when abandoning vaccination, which has saved millions of lives, is discussed openly as a viable option among the educated public. I could go on, but the point is clear: More people need to know and use the basic tools of science in their daily life.Helfand’s book carries on the tradition of works like The Demon-Haunted World: Science as a Candle in the Dark by Carl Sagan (Random House, 1995), The Magic of Reality: How We Know What’s Really True by Richard Dawkins (Free Press, 2011) and even A Short History of Nearly Everything by Bill Bryson (Broadway Books, 2004) that explain the value and impact of scientific habits of mind and the knowledge and understanding those habits deliver.I was in graduate school when Sagan’s book came out, and it reinforced much of what I had already learned through my many years of science-focused education. That having a sense of scale is important. That knowing what is probable and what is unlikely is important. That causality and correlation aren’t the same thing. That back-of-the-envelope calculations provide rough answers to tough questions. Helfand’s chapters walk us through similar lessons and even provide chapter-by-chapter exercises to test and improve our skills. I enjoyed those problems, which played out more like enjoyable puzzles than algebra homework sets from long ago.Helfand strays from his central theme by including a mild rant on the importance of linguistic rules, but he admits partway through it that the detour is at least partly due to his pedantic tendencies. One can forgive him and move on to the important conclusion of the section: that words matter because they contain information and therefore deserve our attention just as much as numbers. Having worked in close collaboration with Helfand during his recent tenure as president of the American Astronomical Society, I can assure you that he is a wee bit pedantic, but that tendency enhanced his excellent and effective leadership. He has also used the principles expressed in A Survival Guide to inform the educational philosophy of Quest University Canada, which he describes in two enjoyable TEDx talks about the need to change the way we educate university students.As practitioners of science, we rarely step back and think about how we go about our work. We’re too busy getting the work done. But reading through this survival guide, I was struck by the extraordinary power provided by a few simple tools fundamental to science. Sitting here on our small planet we have determined both the scale and the history of our universe, revealed the physical changes Earth has experienced over a time span far in excess of our own lifetimes or that of our species, outlined the basic function of our brains and bodies, revealed the fundamental ways matter interacts and the forces that guide those interactions, and pierced the inner working of things so small we cannot even see them through microscopes. The tools of our trade are powerful, and scientifically inclined readers will enjoy the way Helfand reminds them of that fact. But if this book motivates appreciation of those tools and their application beyond our own community, then we’ll really be on our way to a better world.© 2016 American Institute of Physics.

In this paper, we introduce methods for evaluating climate model performance across spatial scales. These techniques are based on the scale space framework widely used in the image processing and computer vision communities. We discuss why the diffusion equation on the sphere provides a particularly attractive means of smoothing two-dimensional maps of global climate data. We establish that no structure is introduced into a map as an artifact of the smoothing procedure. This allows for the comparison of models and observations at multiple scales. As a test case for these methods, we compare the ability of high- and low-resolution versions of the Community Climate System Model (CCSM) to simulate the seasonal climatologies of surface air temperature (TAS), sea level pressure (PSL), and total precipitation rate (PR). For TAS, we find that the high-resolution model is better able to capture the boreal summer (JJA) climatological pattern at fine scales, although there is no such improvement in winter (DJF). We find the performances of the high- and low-resolution models to be similarly capable of capturing the summertime sea level pressure climatology at all scales. However, the high-resolution model PSL climatology is degraded for DJF, especially at larger scales. For both JJA and DJF precipitation climatologies, we find larger precipitation errors in the high-resolution model at the finest scales; however, performance at larger scales is improved.

We report the detection of four water masers within the Small Magellanic Cloud (SMC); two discovered with the 70-m Tidbinbilla radio telescope, and two discovered with the Australia Telescope Compact Array (ATCA). Precise positions of all four masers have been derived from ATCA observations, and the characteristics of each water maser have been monitored over a period of several years. Sensitive observations towards two previously detected water masers reported in the literature failed to detect any emission. The detected water masers show evidence of higher levels of temporal variability than equivalent Galactic sources, and one of the features associated with NGC346 IR1 shows an acceleration of 9.6 km/s yr^-1 over a 31 day period. Sensitive targeted observations for methanol and OH masers failed to detect any accompanying emission - in the case of methanol perhaps highlighting an under abundance in the SMC, consistent with expectations due to lower metallicity. The water masers are both bright and compact making them excellent targets for Very Long Baseline Interferometry (VLBI) observations, which can potentially measure the proper motion of the SMC (~1 - 2 mas yr^-1) with temporal baselines of ~12 months. Such observations would utilise sources associated with only the current epoch of star formation and hence have several advantages over alternative methods.

Aims. A multi-transition survey of HCN (sub-) millimeter line emission from a large sample of asymptotic giant branch (AGB) stars of different chemical type is presented. The data are analysed and circumstellar HCN abundances are estimated. The sample stars span a large range of properties such as mass-loss rate and photospheric C/O-ratio. The analysis of the new data allows for more accurate estimates of the circumstellar HCN abundances and puts new constraints on chemical models.Methods. In order to constrain the circumstellar HCN abundance distribution a detailed non-local thermodynamic equilibrium (LTE) excitation analysis, based on the Monte Carlo method, is performed. Effects of line overlaps and radiative excitation from dust grains are included.Results. The median values for the derived abundances of HCN (with respect to H-2) are 3 x 10(-5), 7 x 10(-7) and 10(-7) for carbon stars (25 stars), S-type AGB stars (19 stars) and M-type AGB stars (25 stars), respectively. The estimated sizes of the HCN envelopes are similar to those obtained in the case of SiO for the same sample of sources and agree well with previous results from interferometric observations, when these are available.Conclusions. We find that there is a clear dependence of the derived circumstellar HCN abundance on the C/O-ratio of the star, in that carbon stars have about two orders of magnitude higher abundances than M-type AGB stars, on average. The derived HCN abundances of the S-type AGB stars have a larger spread and typically fall in between those of the two other types, however, slightly closer to the values for the M-type AGB stars. For the M-type stars, the estimated abundances are much higher than what would be expected if HCN is formed in thermal equilibrium. However, the results are also in contrast to predictions from recent non-LTE chemical models, where very little difference is expected in the HCN abundances between the various types of AGB stars.

We present single-dish and very long baseline interferometry observations of an outburst of water maser emission from the young binary system Haro 6-10. Haro 6-10 lies in the Taurus molecular cloud and contains a visible T Tauri star with an infrared companion 1.'' 3 north. Using the Very Long Baseline Array, we obtained five observations spanning three months and derived absolute positions for 20 distinct maser spots. Three of the masers can be traced over three or more epochs, enabling us to extract absolute proper motions and tangential velocities. We deduce that the masers represent one side of a bipolar outflow that lies nearly in the plane of the sky with an opening angle of similar to 45 degrees. They are located within 50 mas of the southern component of the binary, the visible T Tauri star Haro 6-10S. The mean position angle on the sky of the maser proper motions (similar to 220 degrees) suggests they are related to the previously observed giant Herbig-Haro (HH) flow which includes HH 410, HH 411, HH 412, and HH 184A-E. A previously observed HH jet and extended radio continuum emission (mean position angle of similar to 190 degrees) must also originate in the vicinity of Haro 6-10S and represent a second, distinct outflow in this region. We propose that a yet unobserved companion within 150 mas of Haro 6-10S is responsible for the giant HH/maser outflow while the visible star is associated with the HH jet. Despite the presence of H-2 emission in the spectrum of the northern component of the binary, Haro 6-10N, none of outflows/jets can be tied directly to this young stellar object.

Open Access, defined as the free provision of information by science publishers, is not likely to be mandated by law anytime soon in the United States. A collaborative effort, initiated by the House Science Committee, to come to some consensus within the scientific publishing enterprise has resulted in the release of the so-called “Roundtable Recommendations”. These will serve as a working model moving forward on fundamental shared starting points for both publishers and authors as well as the Open Access community. The AAS’ delayed open access model for publishing is flexible, supportive of our discipline and equitably distributes the cost of publishing to authors and readers. The AAS can support this flexible model because it is not dependent on journal revenues for the support of its member-focused activities.

We present results of VLBI observations of the water masers associated with IRAS 4A and IRAS 4B in the NGC 1333 star-forming region taken in four epochs over a two month period. Both objects have been classified as extremely young sources, and each source is known to be a multiple system. Using the Very Long Baseline Array, we detected 35 masers in epoch I, 40 masers in epoch II, 35 in epoch III, and 24 in epoch IV. Only one identified source in each system is associated with these masers. These data are used to calculate proper motions for the masers and trace the jet outflows within 100 AU of IRAS 4A2 and IRAS 4BW. In IRAS 4A2 there are two groups of masers, one near the systemic cloud velocity and one redshifted. They expand linearly away from each other at velocities of 53 km s−1. In IRAS 4BW, masers are observed in two groups that are blueshifted and redshifted relative to the cloud velocity. They form complex linear structures with a thickness of 3 mas (1 AU at a distance of 320 pc) that expand linearly away from each other at velocities of 78 km s−1. Neither of the jet outflows traced by the maser groups align with the larger scale outflows. We suggest the presence of unresolved companions to both IRAS 4A2 and 4BW.

We present Very Long Baseline Array observations of the kinematics of the water masers associated with OH 12.8-0.9, the fourth member of the so-called water-fountain class of sources. We find that the masers occupy two distinct regions at the ends of a bipolar jetlike structure oriented north-south, with the blueshifted masers located to the north and the redshifted masers to the south. The masers are distributed along arclike structures 12-20 mas across that are oriented perpendicular to the separation axis with an angular separation of ~110 mas on the sky. Our multiepoch observations show the two maser arcs to be expanding away from each other along the axis of separation. The relative proper motions of the two maser regions is 2.7 mas yr-1 (~105 km s-1 at the assumed distance of 8 kpc). The measured radial velocity difference between the northern blueshifted masers and the southern redshifted masers is 48.4 km s-1. The radial velocity, when combined with the proper motion, yields a three-dimensional expansion velocity of 58 km s-1 and an inclination angle of 24° for the jet. By combining our radial velocities with historical values, we estimate the three-dimensional acceleration of the masers to be ~0.63 km s-1 yr-1 and a dynamical age for the collimated outflow of ~90 yr.

We present the latest results of a multi-line study of SiO circumstellar masers in oxygen-rich AGB stars using the VLBA.In particular, we have studied several maser lines at 43 GHz (v=1 and v=2) and at 86 GHz (v=1 and v=2) of 28 SiO, and for the first time we have been able to map the emission of the ground state v=0 J=1-0 of 29 SiO and the v=2 J=2-1 maser line of 28 SiO.In TX Cam, the 3-mm emission is produced in an outer region of the circumstellar envelope, as it has been already observed in other late-type stars.We also discuss the importance of these new detections in the framework of the SiO maser pumping models.