Bullying rife in astronomy and geophysics

Astronomy and geophysics have a systemic bullying and harassment problem, according to an investigation by the Royal Astronomical Society (RAS).

Valor da ciência, defesa do conhecimento e Perspectival Realism: Entrevista com Michela Massimi

Michela Massimi é professora de Filosofia da Ciência no Departamento de Filosofia da Universidade de Edimburgo, onde também é afiliada ao Higgs Centre for Theoretical Physics. Membro de importantes sociedades filosóficas e científicas, como a Royal Society of Edinburgh, a Royal Astronomical Society, e a Académie Internationale de Philosophie des Sciences (membro correspondente) é presidente eleita da PSA, Philosophy of Science Association, para o biênio 2023-2024. Massimi, com dupla nacionalidade, italiana e britânica, estudou na Sapienza Università di Roma, na London School of Economics, e lecionou História e Filosofia da Ciência na University College London antes de mudar-se para Edimburgo. Massimi trabalha com Filosofia da Ciência em uma abordagem marcada pelo recurso à pesquisa histórica. Seus interesses amplos abarcam a Filosofia da Cosmologia, o realismo científico, os estudos de ciências, as relações entre ciência e sociedade, entre outros tópicos. Tem se destacado por defender o que chama de Perspectival Realism, se afastando tanto do realismo tradicional, quanto do pragmatismo e do relativismo. Nessa entrevista dialogamos com Massimi sobre temas como o valor da ciência, a defesa da ciência em épocas de negacionismo e obscurantismo e as características de sua posição filosófica.

A British Sky: Imperial Networks and the Symbiotic Relationship Between Imperialism and Astronomy in the Nineteenth-Century British Empire

Despite modern perceptions of science as an apolitical, irreligious, democratizing force, science has historically been a tool used by individuals and organizations for their own purposes. In the case of late European empires, science and scientific “progress” were valuable tools for agendas of Christianization and civilization. Moreover, scientists and scientific methods could be used to further the types of work needed to grow empire – such as a map-making and exploration. However, the relationship between science and empire was not limited to imperial domination. Scientists and scientific bodies could also use the tools of empire to further their scientific work. The Royal Astronomical Society is an excellent example of the “use” of empire – most of its funding came from imperial pundits looking to entrench British superiority. Among the various scientific disciplines practiced in the nineteenth century, astronomy played an interesting role in entrenching the relationship between science and empire – particularly as it was practiced on the fringes of the British empire. Growing empires necessitated the creation and proliferation of new technologies that in turn made practicing science in recently acquired colonies much easier. The interconnected web of new technologies, scientists, and imperial structures of power and politics combined with scientific desires, colonial ideals, race relations, and imperial economies of trade and knowledge to produce an incredibly complicated vision of science. Astronomy, in its looking to the heavens, reflected back upon earthly issues to ultimately reveal the tangled ideologies that permeated British imperial science at this time. This story of British imperial astronomy is meant to complicate modern notions of what science is and has been.

Spectroscopic study of Ceres' collisional family candidate members: taxonomic classification and comparison to Ceres' surface.

<p>Despite the observed signs of large impacts on the surface of Ceres, there is no confirmed collisional family associated with this dwarf planet. Carruba et al. (2016) carried out a dynamical study in the ‘pristine region’ of the main asteroid belt and proposed a sample of 156 asteroids as candidates to be members of a Ceres’ collisional family. Our main objective in this work is to study the spectral link between Ceres and a total of 14 observed asteroids among the family candidate samples proposed by Carruba et al. (2016) to explore their potential membership to the collisional family.</p> <p>For this aim we obtained visible spectra of these 14 asteroids using the OSIRIS spectrograph at the 10.4m Gran Telescopio de Canarias (GTC), located at the El Roque de los Muchachos Observatory (La Palma, Spain), managed by the Instituto de Astrofísica de Canarias (IAC). We reduced the raw images and extracted the spectra with a semi-automatic Python-based pipeline. After that, we computed spectral slopes in two different wavelength ranges: one in the visible (490-800 nm) and one in the visible-near-infrared (800-920 nm) to compare the obtained values with those in Ceres’ surface already Ncomputed by Rousseau et al. (2020) using the spectrometer onboard the NASA Dawn spacecraft.</p> <p>We present the spectra and the taxonomy of 14 observed asteroids, their taxonomy, and calculated slopes. We concluded that only one asteroid could be compatible with an origin in a primitive collision at Ceres. We have also found a hydration band at 700 nm, also found in the surroundings of crater Occattor (Rizos et al. 2019). On the other hand, we have also found a relation between the spectral slope of the craters in Ceres’ surface and their age in both wavelength ranges. This behavior could be related to space weathering.</p> <p>Exploring the sample as a whole, the variability in member’s taxonomy and the differences in their spectral slopes makes us conclude that they cannot be considered as members of a collisional family of Ceres. However, the presence of a hydration band in one of the asteroids could be proof that such a family may have existed.</p> <p> </p> <p> </p> <p>Bibliography:</p> <p>Carruba, V., Nesvorný, D., Marchi, S., & Aljbaae, S. 2016, Monthly Notices of the Royal Astronomical Society, 458, 1117</p> <p>Rousseau, B., De Sanctis, M. C., Raponi, A., et al. 2020, A&A, 642, A74</p> <p>Rizos, J. L., de León, J., Licandro, J., et al. 2019, Icarus, 328, 69</p>

Bringing early colonial astronomy to life

Anna Ridley describes a new exhibition at Old Government House, Sydney, that uses documents from the Royal Astronomical Society library and archive – and technology – to help tell the story of scientific endeavour in colonial New South Wales

A composite luminous and dark flight model allowing strewn field prediction

<p>As of today, instrumentally observed meteorite falls account for only 37 recovered meteorite cases, with derived Solar System orbit, out of 65098 registered meteorite names. To bridge this knowledge gap, a number of fireball networks have been set up around the globe. These networks regularly obtain thousands of records of well-observed meteor phenomena, some of which may be classified as a likely meteorite fall (Sansom et al. 2019). A successful recovery of a meteorite from the fireball event often requires that the science team can be promptly directed to a well-defined search area. Here we present a neat Monte Carlo model, which comprises adequate representation of the processes occurring during the luminous trajectory coupled together with the dark flight (Moilanen et al. 2021). In particular, the model accounts for fragmentation and every generated fragment may be followed on its individual trajectory. Yet, the algorithm accounts only for the mass constrained by the observed deceleration, so that the model does not overestimate the total mass of the fragments on the ground (and this mass may also be retrieved as zero). We demonstrate application of the model using historical examples of well-documented meteorite falls, which illustrate a good match to the actual strewn field with the recovered meteorites, both, in terms of fragments’ masses and their spatial distribution on the ground. Moreover, during its development, the model has already assisted in several successful meteorite recoveries including Annama, Botswana (asteroid 2018 LA), and Ozerki (Trigo-Rodríguez et al. 2015, Lyytinen and Gritsevich 2016, Maksimova et al. 2020, Jenniskens et al. 2021).</p><p>References</p><p>Jenniskens P. et al. (2021). Asteroid 2018 LA, impact, recovery and origin on Vesta. Submitted to Science.</p><p>Lyytinen E., Gritsevich M. (2016). Implications of the atmospheric density profile in the processing of fireball observations. Planetary and Space Science, 120, 35-42 http://dx.doi.org/10.1016/j.pss.2015.10.012</p><p>Maksimova A.A., Petrova E.V., Chukin A.V., Karabanalov M.S., Felner I., Gritsevich M., Oshtrakh M.I. (2020). Characterization of the matrix and fusion crust of the recent meteorite fall Ozerki L6. Meteoritics and Planetary Science 55(1), 231–244, https://doi.org/10.1111/maps.13423 </p><p>Moilanen J., Gritsevich M., Lyytinen E. (2021). Determination of strewn fields for meteorite falls. Monthly Notices of the Royal Astronomical Society, in revision.</p><p>Sansom E.K., Gritsevich M., Devillepoix H.A.R., Jansen-Sturgeon T., Shober P., Bland P.A., Towner M.C., Cupák M., Howie R.M., Hartig B.A.D. (2019). Determining fireball fates using the α-β criterion. The Astrophysical Journal 885, 115, https://doi.org/10.3847/1538-4357/ab4516</p><p>Trigo-Rodríguez J.M., Lyytinen E., Gritsevich M., Moreno-Ibáñez M., Bottke W.F., Williams I., Lupovka V., Dmitriev V., Kohout T., Grokhovsky V. (2015). Orbit and dynamic origin of the recently recovered Annama’s H5 chondrite. Monthly Notices of the Royal Astronomical Society, 449 (2): 2119-2127, http://dx.doi.org/10.1093/mnras/stv378</p>

RAS200: bringing astronomy and geophysics to new audiences

<p>This year sees the Royal Astronomical Society – the oldest learned society covering astronomy and geophysics in the world – celebrate its 200<sup>th</sup> anniversary. In the run up to 2020, the RAS initiated an outreach and engagement scheme aimed at bringing the society’s sciences to new audiences, those who might not normally attend public lectures, planetarium shows or even star-gazing evenings. Committing £1 million to the project, the RAS deliberately sought out new partners who would take it out of its comfort zone with a bottom-up funding scheme making up to £100k available for five-year projects. Competition for the funding was fierce with just 12 projects funded out of more than 150 applications.</p> <p> </p> <p>Starting in 2015, the Prince’s Trust has used astronomy to inspire young people who have had some of the hardest starts in life. Carers who hardly ever get a break from their duties are funded to spend weekends learning about the stars on the Scottish island of Coll. A new planetarium show using Holst’s classic “Planet Suite” and modern adaptations brings the heavens in Full-dome 360 animation to audiences via mobile planetaria. New courses for adults who missed out on their education first time round have been developed. And Welsh cultural festivals now resonate to poetry, dance and music inspired by astronomy.</p> <p> </p> <p>Starting two years later, geophysics is being used to engage football crowds with science, and prisoners are being helped maintain links with their families through astronomy. In Cornwall, Galway and South Africa, artworks, trails and exhibitions are taking astronomy out to local people. And young girls and women in the Girl Guides have new badges to work for. All of these projects, too, are being adapted to suit people on the autistic spectrum.  All projects are being evaluated and all publicised as widely as possible.</p> <p> </p>

The structure of the co-orbital stable regions as a function of the mass ratio

<p>In the past years, astronomers have discovered many non-planetary structures in extrasolar systems such as a comet (Kiefer et al. 2014), an asteroid belt (Moro-Martín et al. 2008), an exoplanetary ring (Kenworthy & Mamajek 2015), and more recently the formation of an exomoon (Isella et al. 2019). But, although the search for exotrojans has not had success so far (e.g. Lillo-Box, J. et al. 2018), they must be as common as they are in the Solar System.</p> <p>Co-orbital systems were widely studied, and there are several works on stability and the formation of these structures. However, for the size and location of the stable regions, authors usually describe their results but do not provide a way to find them without numerical simulations and, in most works, the mass ratio value range is small. In the current work, we aimed to study the structure of co-orbital stable regions for a wide range of mass ratio systems and built empirical equations to describe them. It allows estimating the size and location of co-orbital stable regions from a few system’s parameters.</p> <p>In our recently published work (Liberato & Winter 2020), we have distributed thousands of massless particles in the co-orbital region of a massive secondary body adopting the planar circular restricted three-body problem. Using the N-body integrator Mercury (Chambers 1999) with the Bulirsh-Stoer integrator, we performed numerical simulations for a wide range of mass ratios (μ) for 7x10<sup>5</sup> orbital periods of the secondary body.</p> <p>We divided the results into two groups, the horseshoe and tadpole stable regions. We found that the horseshoe regions upper limit is between 9.539 × 10<sup>-4</sup>< μ < 1.192 × 10<sup>-3</sup>, which correspond to a minimum angular distance from the secondary to the separatrix between 27.239° and 27.802°. We also found that the limit to exist stability in the co-orbital region is about μ = 2.3313 × 10<sup>-2</sup>. That value is much smaller than the predicted by the linear theory, but we haven’t studied the stability for mass ratio values greater than 2.785×10<sup>-2</sup>. We have fitted polynomial functions to our results to describe the stable region parameters to represent estimates of the maximum angular and radial widths of the co-orbital stable regions for any system with 9.547 × 10<sup>-5 </sup>≤ μ ≤ 2.331 × 10<sup>-2</sup>.</p> <p> </p> <p>References:</p> <p>-Chambers J. E., 1999, Monthly Notices of the Royal Astronomical Society, 304, 793</p> <p>-Isella A., Benisty M., Teague R., Bae J., Keppler M., Facchini S., Pérez L.,2019, The Astrophysical Journal, 879, L25</p> <p>-Kenworthy M. A., Mamajek E. E., 2015, The Astrophysical Journal, 800, 126</p> <p>-Kiefer F., Lecavelier des Etangs A., Boissier J., Vidal-Madjar A., Beust H., Lagrange A. M., Hébrard G., Ferlet R., 2014, Nature, 514, 462</p> <p>-L. Liberato, O. C. Winter, The structure of the co-orbital stable regions as a function of the mass ratio, 2020, Monthly Notices of the Royal Astronomical Society, , staa1727, <a href="https://doi.org/10.1093/mnras/staa1727">https://doi.org/10.1093/mnras/staa1727</a></p> <p>-Lillo-Box, J. Barrado, D. Figueira, P. Leleu, A. Santos, N. C. Correia, A. C. M. Robutel, P. Faria, J. P. 2018, Astronomy & Astrophysics, 609, A96</p> <p>-Moro-Martín A., Wyatt M. C., Malhotra R., Trilling D. E., 2008, The Solar System Beyond Neptune, p. 465</p>

Further constraints on activity models of comet 67P/Churyumov-Gerasimenko with Rosetta data

<p>Cometary outgassing produces a back-reaction force on a nucleus that can alter its trajectory and rotation state. Understanding this activity is key to exploring the physics of the upper layers of cometary surfaces, with implications for their formation and subsequent evolutionary history, and can be constrained by observing the orbit and rotation changes. For comet 67P/Churyumov-Gerasimenko, detailed measurements have been made by the Rosetta spacecraft and various attempts have been made to model the activity (see, e.g. [1,2]).</p><p>Here we will present updated work using the activity model of [2] to fit to Rosetta outgassing, trajectory, and rotation data. We test a number of different activity distributions over the surface of the comet by varying the Effective Active Fraction (EAF), relative to pure water ice, of facets on a shape model. The previous work has shown that, in order to fit the fast ramp-up and fall-off in outgassing either side of perihelion, 67P’s EAF must vary with time. We therefore investigate a number of different EAF curves to see if different parametric models can be ruled out. The objective here is to constraint the shape of the activity curve that a more advanced thermo-physical model (see, for example [3,4]) must produce in order to fit the data. We also investigate different spatial patterns in EAF, and attempt to correlate them to physical features on the cometary surface. Here we are able, for the first time, to achieve a good fit to the Rosetta data by parameterizing EAF in terms of the different geological unit types on 67P (Fig. 1). This may have important implications for understanding how activity works on the different types of surface observed on cometary nuclei, including ‘rough’, ‘smooth’, ‘dusty’ and ‘rocky’ surface morphologies. Finally, in addition to the changes in rotation period examined in [2], we also compute changes in the rotation axis in order to compare with the observations.</p><p><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.a40b65df80fe55673282951/sdaolpUECMynit/0202CSPE&app=m&a=0&c=f8cb6140092ce98ec083408a35de649e&ct=x&pn=gnp.elif" alt=""></p><p><strong>References</strong></p><ol><li>Nongravitational Effects of Cometary Activity. S. Mottola, N. Attree, L. Jorda, H.U. Keller, R. Kokotanekova, D. Marshall. Space Science Reviews 216 (1), 1-20</li> <li>Constraining models of activity on comet 67P/Churyumov-Gerasimenko with Rosetta trajectory, rotation, and water production measurements. N. Attree, L. Jorda, O. Groussin, S. Mottola, N. Thomas, Y. Brouet, E. Kührt. Astronomy & Astrophysics 630, A18</li> <li>On the activity of comets: understanding the gas and dust emission from comet 67/Churyumov-Gerasimenko’s south-pole region during perihelion. B. Gundlach, M. Fulle, J. Blum. Monthly Notices of the Royal Astronomical Society, Volume 493, Issue 3, April 2020, Pages 3690–3715</li> <li>Near-perihelion activity of comet 67P/Churyumov–Gerasimenko. A first attempt of non-static analysis. Yu. Skorov, H. U. Keller, S. Mottola and P. Hartogh. Monthly Notices of the Royal Astronomical Society, Volume 494, Issue 3, May 2020, Pages 3310–3316</li> </ol>

Research paper abstracts in Monthly Notices of the Royal Astronomical Society (1943–2018)

We report the findings of a diachronic study of 100 research paper abstracts published in four different periods (from 1943 to 2018) in Monthly Notices of the Royal Astronomical Society, one of the most prestigious astrophysics journals written in English. Our main results show that research paper abstracts have evolved over time in the sense that they have become longer, more informative and more precise. They also reveal an overall increase in the number of authors, active and modal verbs, self-mentions and compound groups per total number of words. Likewise, compound structures are becoming more and more complex. These outcomes may be explained in terms of a rising collaboration scenario and an attempt to increase authors’ visibility.