Fabrication of large UV transmission blazed gratings for slitless spectral sky survey

Slitless spectral sky survey is a critical direction of international astronomical research. Compared with ground-based sky survey, space-based sky survey can achieve full-band observation, and its imaging quality and resolution capability are restricted by the efficiency and size of dispersive elements. Transmission blazed gratings are often used as the dispersive elements in the UV band. Holographic interference lithography produces the photoresist mask of a grating, and the ion beam etching vertically transfers the pattern to the substrate to form the SiO2 mask of a grating. To reduce the effect of ion beam divergence on the uniformity of the groove shape, the grating mask is etched tilted by the ion beam passing through a narrow slit to obtain a blazed grating with consistent structural parameters. Moreover, two-dimensional scanning of the sample stage enables the etching of large-size samples. A UV transmission blazed grating with a linear density of 333 lines mm−1, a blazing angle of 11.8°, and a dimension of 99.2mm × 60.0mm × 6.0mm was successfully fabricated with an average diffraction efficiency of 66%, a PV diffraction wavefront of 0.169λ (λ = 632.8 nm) and low stray light.

BIOLOGICAL SESSION“THE IMPORTANCE OF G. GAMOW'S IDEAS FOR BIOLOGY OF THE 21st CENTURY” AT THE XXI GAMOW INTERNATIONAL ASTRONOMICAL CONFERENCE-SCHOOL IN ODESSA (15-21 AUGUST, 2021)

Третій рік поспіль в межах Гамовської конференції працює Біологічна секція: «Важливість ідей Г.А. Гамова для біології 21-ого століття», організація якої викликана великою повагою до особистості вченого Георгія Антоновича Гамова, наукові інтереси якого об’єднали астрофізику, космологію та молекулярну біологію. Цього року Біологічна секція працювала в режимі on-line 17.08.2021. Роботу секції розпочали з виступу професора Тобіуса Дельбрюка (Institute of Neuroinformatics – ETH and University of Zurich, Zurich, Switzerland), сина видатного фізика, Нобелевського лауреата Макса Дельбрюка (в певний період товариша Г.А. Гамова). Професор Тобіус Дельбрюк назвав свою доповідь – "Out of this world: Recounting Max's Delbruck memories of George Gamow”. Ця доповідь, присвячена феноменальній особистості Г.А. Гамова, придала засіданню біологічної секції емоційну атмосферу наближення до великих ідей, що надали і зараз надають поштовх для розвитку молекулярної біології. Значну зацікавленість учасників секції викликала доповідь Dr. V.N. Korzun (KWS SAAT SE & Co. KGaA (м. Айнбек, Німеччина) «Applications of genetic and genomic research in cereals», що продемонструвала впровадження в селекційний процес сучасних молекулярно-генетичних технологій. З доповіддю «DNA-protein interactions as a tool of synthetic biology», що присвячена високо технологічним розробкам зі створення біосенсорів науково-виробничою фіромою Explogen LLC (EXG) (м. Львів, Україна) виступив к.б.н. Ю. Ребець. Наступна пленарна доповідь «Using the G.A. Gamow’s ideas for molecular genetic diagnostics of infectious and somatic human diseases at the current stage of medical development» була представлена білоруськими вченими, а саме професор С.А. Касцьюк розповіла про молекулярно-генетичні дослідження, що виконуються в Білоруській медичній академії післядипломної освіти. Dr. Yu. Monchak з McGill University (м. Монреаль, Канада) також представив доповідь присвячену впровадженню ДНК-технологій в діагностику патології людини ˗ «Targeted therapy, DNA sequence and the race against neoplasia». Ця доповідь викликала велику зацікавленість учасників біологічної секції. Молоді науковці Іщенко О.О., Жарікова Д.О., Роман І.І., Доля Б., Рошка Н.М., Чубик І.Ю., Попович Ю.А., Топораш М.К., Пидюра М.О. – доктори філософії з біології, кандидати наук, аспіранти, що займаються дослідженнями в галузі молекулярної біології представили дев’ять доповідей, що відбивають результати виконаних досліджень у низці провідних університетів нашої країни, а саме у Львівському національному університеті ім. І. Франка, у Одеському національному університеті імені І.І. Мечникова, у Чернівецькому національному університеті ім. Юрія Федьковича та ДУ «Інституті харчової біотехнології та Геноміки» (м. Київ). Представлені доповіді викликали жвавий інтерес, а формат on-line дозволів об’єднати у роботі секції понад 35 учасників з різних країн ˗ України, Білорусі, Швейцарії, Німеччини, Канади і Казахстану.

Low cost equipment for astronomical spectroscopy

The purpose of this paper is to show how we can obtain spectra for different astronomical objects using low coat equipment. Where a high-efficiency diffraction grating named “The Star Analyzer” was used by the International Astronomical Center (IAC) in Abu Dhabi, UAE to get the spectrum of different astronomical objects. Balmer series was readily visible when observing an “A” type star. TiO absorptions lines were distinguished by observing an “M” type star. Methane absorption lines were visible by observing Uranus and Neptune. Whereas HI and HeI emission lines were detected by observing a blue hypergiant. In addition, C2 Swan band absorption lines were identified by observing a red giant carbon star. This type of observation is very interesting for public outreach as well as university students, because it shows astrophysical principles for public and students practically and by using low cost equipment.

Women in Astronomy in Belgium

<p>We are attempting to gather all information available to study the question of the representation of women in astronomy in Belgium, which is not a straightforward task.</p> <p>In an early study, [1] analysed gender-specific statistics on the Belgian physicists. One of the difficulties they found was that Belgium keeps different statistics for the French-speaking and Flemish universities, and the career structure is different depending on the Communities.</p> <p>As preliminary analysis, we investigated the percentage of women in the International Astronomical Union (IAU) registered in the database for Belgium [2]. The IAU is an international organization with participation from 68 countries that covers the main areas of astronomy, including planetary science. In 2021, 32 out of 144 Belgian members were female (22%). It is important to notice that not all astronomers in Belgium, and in particular not the younger generation where the percentage of female researchers is higher, are member of IAU. Therefore we expect these values to underestimate the true number of women in the field. In view of the fact that it is the same at the level of the funding bodies and, by construction, at the universities, Earth and Space Sciences will be considered together. We will present preliminary results of our study.</p> <p><strong>References:</strong></p> <p>[1] Petra Rudolf, Vice‐President, Christine Iserentant, Muriel Vander Donckt, Nathalie Balcaen, Peggy Fredrickx, Karen Janssens, and Griet Janssen, "Women in Physics in Belgium: Still a Long Way From Achieving Gender Equality", AIP Conference Proceedings 628, 131-132 (2002) https://doi.org/10.1063/1.1505297</p> <p>[2] https://www.iau.org/administration/membership/individual/distribution/</p>

Astronomy for Development actions in the context of long-standing refugee situations: the "Amanar: under the same sky" initiative

<p>"Amanar: under the same sky" is a science outreach project organized by GalileoMobile, the Asociación Canaria de Amistad con el Pueblo Saharaui (ACAPS) and the Instituto de Astrofísica de Canarias (IAC), with the aim to support and inspire the Sahrawi community from the refugee camps in Tindouf, Algeria, using Astronomy. The initiative pays special attention to Sahrawi children and youth to awaken their interest in science and stimulate their imagination and critical thinking. The project also promotes mutual understanding and cultural exchange through the study and preservation of the Saharawi rich astronomical traditions and knowledge of the sky. Amanar was selected as a “Special Project” of the International Astronomical Union (IAU) centenary celebrations, and has received funding from the IAU Office of Astronomy for Development and the Europlanet Funding Scheme. It counts with the support and collaboration of international astronomical institutions and a significant number of local partners.</p> <p>The first part was developed in three of the Canary Islands in summer 2019. It combined visits to the professional observatories with educational activities about the Universe and astronomical observations for the Sahrawi children who spend every summer in the islands together with Spanish families, within the long-standing “Holidays in Peace” program. The second part took place in October 2019, when a team of astrophysicists, science communicators and filmmakers visited the Sahrawi refugee camps in Tindouf to promote Astronomy outreach activities in schools and donate telescopes and educational materials. Teacher workshops were also organized to encourage educators to use Astronomy as a didactic tool and contribute to the improvement of the quality of education in the region.</p> <p>As a reaction to the COVID-19 Pandemic in 2020, the project provided follow-up capacity building for Sahrawi teachers through a pilot online training programme through WhatsApp, which is efficient to low internet connection and easier to use in their mobile phones. The program content was co-created with the teachers to ensure that was relevant to them. In total, 635 children, 83 teachers and 150 people from the general public participated in all the project activities. In addition, thanks to a collaboration with the Sahrawi Oral History Department, a series of interviews were organized with elders about their Astronomical knowledge. In 2021 we are expanding this study by awarding internships to young Sahrawi people, who will be trained on Ethnoastronomy and ethnographic data collection, so they are the ones leading the process of preserving their own culture and history.</p> <p>In this talk, we will present the outcomes and best practices learned from the project so far, the planned actions to ensure long-term sustainability along with future visits to the camps. We will also discuss the global impact of this type of initiatives in the framework of Astronomy for Development.</p>

Development of astronomy teaching materials to overcome visual impairment. IAU Working Group, Astronomy for Equity and Inclusion IAU Symposium358

It is important that science is inclusive and communication is prioritised. To make science accessible to all, the gap between highly specific research and people with a general interest in science must be bridged. Effective science communication also helps to engage young people and inspire them to pursue a career in science. In Tokyo, Japan, Dr Kumiko Usuda-Sato, National Astronomical Observatory of Japan (NAOJ), and Dr Lina Canas of the International Astronomical Union (IAU) Office for Astronomy Outreach (OAO), are working to achieve effective communication and full inclusion. The researchers are interested in ensuring that science reaches diverse people, including people with a disability such as blind and visually impaired (BVI) people, as well as promoting diversity and inclusivity within international astronomical research communication. To this end, Usuda-Sato is engaging with the BVI community and tactility experts at the Japan Braille Library. A key focus is on developing resources for helping people to understand the Subaru Telescope, such as 3D printed models, braille and 2D explanations, as well as adapted communication methods. Canas is working to make the research community aware of accessibility issues. A key component of this was the IAU Symposium358, which brought together experts in accessibility and science communication, fostering discussion and promoting international collaboration.

Meridian section projections: a new class of the triaxial ellipsoid projections

Historically the conformal projections have been used for mapping not only the Earth, but other celestial bodies as well. Their application enables preserving the shape of the relief features on the maps, which is extremely important for various analyses of celestial bodies’ surfaces. For many small bodies of the Solar system the International Astronomical Union recommends to apply a triaxial ellipsoid as a reference surface. But if the conformal projections for the reference surfaces of a sphere and an ellipsoid of revolution already exist, obtaining these projections for a triaxial ellipsoid will be significantly complicated, and the task of preserving the shape of relief features still actual. In general, the article deals with cylindrical and azimuthal projections of the meridian section for global mapping the celestial body surface in accordance with the idea formulated by prof. L. M. Bugaevsky. The projections are implemented for mapping of Phobos, moon of Mars.

EPSC 2020 Planetary Science Wiki Edit-a-thon

<p><strong>Background</strong></p><p>Wikipedia is an open source, web-based encyclopedia, allowing anonymous and registered users to create, edit and improve articles. A survey in 2018 showed that as many as 90% of Wikipedia's editors were male and as many as 81% of contributors were from the Global North [1].  </p><p>In addition, there are fewer contributions about women, especially in STEM fields, and they are usually less developed [2]. In October 2014, only 15.53% of English Wikipedia's biographies were about women [3]. The WikiProject <strong>Women in Red</strong> was founded in July 2015 with the objective to address this gender bias in Wikipedia content. They succeeded in increasing the above-mentioned percentage to <strong>18.71%</strong> as of 11 January 2021 [2].</p><p>Today, Wikipedia is within the 20 most popular websites [4] and every month it attracts more than 1 billion unique visitors [5]. Wikipedia therefore has a huge potential to change publics perception of who is doing science and what a scientist ‘looks’ like.</p><p><strong>(Women) planetary scientists on Wikipedia?</strong></p><p>In June 2020, there were only 189 planetary scientist biographies on the English Wikipedia, including 48 biographies of female planetary scientists (25%). This percentage is in agreement with the percentage of women in the International Astronomical Union from all ESA’s Member States (24%) [6], but planetary scientists are clearly underrepresented on Wikipedia. Many of them either do not have a Wikipedia biography yet, or if they do, they are often misclassified under the category of “astronomers” or “astrophysicists”.</p><p><strong>A Planetary Sciences</strong><strong> Edit-a-thon</strong>    </p><p>The Diversity Committee of the Europlanet Society aims to highlight diversity within the planetary science community. Therefore, they organised, in collaboration with Women in Red and WikiDonne, the first <strong>Planetary Science Wiki Edit-a-thon</strong> during the Europlanet Science Congress (EPSC) 2020 [7]. An Edit-a-thon (‘edit marathon’) is an organized event where editors from an online community (such as Wikipedia in this case) write, translate and improve articles on a specific topic [2]. Thirty persons received a basic editing training, resulting in 1 new article and 5 translated ones. A small subgroup still meets every month to continue the project.</p><p><strong>References</strong></p><p>[1] https://meta.wikimedia.org/wiki/Community_Insights/2018_Report</p><p>[2] https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Women_in_Red  </p><p>[3] Eduardo Graells-Garrido, Mounia Lalmas, Filippo Menczer, "First Women, Second Sex: Gender Bias in Wikipedia", arXiv, 9 February 2015, p. 3.</p><p>[4] "Wikipedia.org Traffic, Demographics and Competitors". www.alexa.com. Retrieved October 1, 2019.</p><p>[5] https://stats.wikimedia.org/#/all-wikipedia-projects</p><p>[6] Piccialli A., et al., Participation of women scientists in ESA Solar System missions: a historical trend, Adv. Geosci., 53, 169–182, https://doi.org/10.5194/adgeo-53-169-2020, 2020.</p><p>[7] https://www.europlanet-society.org/epsc-2020-planetary-science-wiki-edit-a-thon/    </p>

Nutation of the non-rigid Earth: Effect of the mass redistribution

In this research, we computed the nutation of the figure axis for a non-rigid Earth model due to the mass redistribution resulting from the lunisolar attraction on the deformable Earth, thus extending our previous work on the precessional motion. The basic Earth model is a two-layer structure composed of a fluid core and an anelastic mantle. We used the Hamiltonian approach, leading to closed-form analytical formulae that describe the nutations in longitude and obliquity of the figure axis as a sum of Poisson and Oppolzer terms. Those formulae were evaluated assuming different Earth rheologies by means of the Love number formalism. In particular, we first computed the effect using the standard model of the International Earth Rotation and Reference Systems Service Conventions (2010) solid tides, and then the Love numbers computed by Williams and Boggs, accounting for the complete oceanic tide contribution, which should provide more consistent and updated values for the nutations. The main amplitudes correspond to the 18.6 yr nutation component and reach 201 μas and −96 μas in the in-phase components in longitude and obliquity, respectively. The obtained values differ greatly from those considered in the current nutation model, IAU2000, of the International Astronomical Union (IAU) – and later similar studies – which includes this effect under the denomination of non-linear terms and derives its numerical contribution on the basis of the Sasao, Okubo, and Saito framework. The differences are significant and reach more than 30 μas for some nutation amplitudes. They can be likely attributed to several factors: an incomplete modelling of the redistribution potential; a different treatment of the permanent tide; and the use of different oceanic tide models.