One of the central characteristics of disciplines is that they create their own particular ways of knowing the world. This process is facilitated by the specialization and refinement of disciplinary-specific semiotic resources over time. Nowhere is this truer than in the sciences, where it is the norm that disciplinary-specific representations have been introduced and then refined by a number of different actors. As a consequence, many of the semiotic resources used in the sciences today still retain some traces of their historical roots.

In this paper we analyse one such disciplinary-specific semiotic resource from the field of Astronomy—the Hertzsprung-Russell diagram. We audit the potential of this semiotic resource to provide access to disciplinary knowledge—what Fredlund et al (2012) have termed its disciplinary affordances. Our analysis includes consideration of the use of scales, labels, symbols, sizes and colour. We show how, for historical reasons, the use of these aspects in the resource may differ from what might be expected by a newcomer to the discipline.

We suggest that some of the issues we highlight in our analysis may, in fact, be contributors to alternative conceptions and therefore propose that lecturers pay particular attention to the disambiguation of these features for their students.

In this paper we are interested in the relationship between disciplinary knowledge and its representation. We carry out a social semiotic analysis of a central tool used in astronomy—the Hertzsprung-Russell (H-R) diagram—in order to highlight its disciplinary and pedagogical affordances. By analysing the relationship between disciplinary knowledge and its representation in this way we claim that it becomes possible to identify potential barriers to student learning—instances where semiotic resources with high disciplinary affordance have low pedagogical affordance for newcomers to the discipline. The astronomy resource that we have chosen to analyse has played a pivotal role in our understanding of stellar evolution and as such it features prominently on all undergraduate astronomy programs. However, like most disciplinary-specific semiotic resources, today’s H-R diagram is the culmination of many years of work by numerous disciplinary experts. Over time, the H-R diagram has been revised and reworked by a number of different actors in order to reconcile it with developing observational and theoretical advances. As a consequence, the H-R diagram that we know today combines many layers of astronomical knowledge, whilst still retaining some rather quirky traces of its historical roots. In this paper we adopt a social semiotic lens to analyse these ‘layers of knowledge’ and ‘historical anomalies’ showing how they have resulted in a number of counterintuitive aspects within the diagram that have successively lowered its pedagogical affordance. We claim that the counterintuitive aspects we identify in our analysis give rise to potential barriers to student disciplinary learning. Using our analysis as a case study, we generalise our findings suggesting four types of barrier to understanding that are potentially at work when meeting disciplinary-specific semiotic resources for the first time. We finish the paper by making some general suggestions about the wider use of our analysis method and ways of dealing with any barriers to learning identified. In the specific case of the H-R diagram, we suggest that lecturers should explicitly tease out its disciplinary affordances by the use of ‘unpacked’ resources that have a higher pedagogical affordance. 

Becoming part of a discipline involves learning to interpret and use a range of disciplinary-specific semiotic resources (Airey, 2009). These resources have been developed and assigned particular specialist meanings over time. Nowhere is this truer than in the sciences, where it is the norm that disciplinary-specific representations have been introduced and then refined by a number of different actors in order to reconcile them with subsequent empirical and theoretical advances. As a consequence, many of the semiotic resources used in the sciences today still retain some (potentially confusing) traces of their historical roots. However, it has been repeatedly shown that university lecturers underestimate the challenges such disciplinary specific semiotic resources may present to undergraduates (Northedge, 2002; Tobias, 1986).

In this paper we analyse one such disciplinary-specific semiotic resource from the field of Astronomy—the Hertzsprung-Russell diagram. First, we audit the potential of this semiotic resource to provide access to disciplinary knowledge—what Fredlund et al (2012) have termed its disciplinary affordances. Our analysis includes consideration of the use of scales, labels, symbols, sizes and colour. We show how, for historical reasons, the use of these aspects in the resource may differ from what might be expected by a newcomer to the discipline. Using the results of our analysis we then created an online questionnaire to probe what is discerned (Eriksson, Linder, Airey, & Redfors, in press) with respect to each of these aspects by astronomers and physicists ranging from first year undergraduates to university professors.

Our findings suggest that some of the issues we highlight in our analysis may, in fact, be contributors to the alternative conceptions of undergraduate students and we therefore propose that lecturers pay particular attention to the disambiguation of these features for their students.

In the late 70’s Gibson (1979) introduced the concept of affordance. Initially framed around the needs of an organism in its environment, over the years the term has been appropriated and debated at length by a number of researchers in various fields. Most famous, perhaps is the disagreement between Gibson and Norman (1988) about whether affordances are inherent properties of objects or are only present when they are perceived by an organism. More recently, affordance has been drawn on in the educational arena, particularly with respect to multimodality (see Linder (2013) for a recent example). Here, Kress et al. (2001) have claimed that different modes have different specialized affordances. Then, building on this idea, Airey and Linder (2009) suggested that there is a critical constellation of modes that students need to achieve fluency in before they can experience a concept in an appropriate disciplinary manner. Later, Airey (2009) nuanced this claim, shifting the focus from the modes themselves to a critical constellation of semiotic resources, thus acknowledging that different semiotic resources within a mode often have different affordances (e.g. two or more diagrams may form the critical constellation).

In this theoretical paper the concept of disciplinary affordance (Fredlund et al., 2012) is suggested as a useful analytical tool for use in education. The concept makes a radical break with the views of both Gibson and Norman in that rather than focusing on the discernment of one individual, it refers to the disciplinary community as a whole. Put simply, the disciplinary affordances of a given semiotic resource are determined by those functions that the resource is expected to fulfil by the disciplinary community. Disciplinary affordances have thus been negotiated and developed within the discipline over time. As such, the question of whether these affordances are inherent or discerned becomes moot. Rather, from an educational perspective the issue is whether the meaning that a semiotic resource affords to an individual matches the disciplinary affordance assigned by the community. The power of the term for educational work is that learning can now be framed as coming to discern the disciplinary affordances of semiotic resources.

In this paper we will briefly discuss the history of the term affordance, define the term disciplinary affordance and illustrate its usefulness in a number of educational settings.

Coming to appropriately appreciate the meaning of algebraic signs is an important aspect in introductory

kinematics. However, in this educational context, the “disciplinary relevant aspects” of algebraic signs across

vector and scalar representations are extremely difficult to discern. Our study explores the “relevance

structure” that one-dimensional kinematics problems evoked for introductory level university physics

students across two very different educational systems which have, in PER terms, progressive teaching

environments: Sweden (n=60) and South Africa (n=24). The outcomes of two previous PER studies are used

to provide the analytic basis for formulating categories of relevance structure. Aspects of a contemporary

PER-developed social semiotics perspective (referred to here in terms of communication practices) are used

to discuss implications for teaching in the given educational context of introductory kinematics.

This theoretical paper introduces a new way to view and characterize learning astronomy. It describes a framework, based on results from empirical data, analyzed through standard qualitative research method- ology, in which a theoretical model for a vital competency of learning astronomy is proposed: reading the sky, a broad description under with various skills and competencies are included. This model takes into account not only disciplinary knowledge but also disciplinary discernment and extrapolating three dimensionality. Together, these constitute the foundation for the competency referred to as reading the sky. In this paper, these competencies are described and discussed and merged to form a new framework vital for learning astronomy to better match the challenges students face when entering the discipline of astronomy.

Att lära sig astronomi, eller naturvetenskap över lag, involverar så mycket och kan liknas vid att lära sig ett nytt språk. Eleven måste lära sig detta språk och det innefattar, förutom skrivet och talat fackspråk, en mängd mer eller mindre begripliga sk representationerna, aktiviteter och verktyg. Det är därför en grannlaga uppgift att lära sig naturvetenskap och eleverna behöver hjälp med att lära sig naturvetenskapens språk. Det sker i allmänhet samtidigt som de lär sig ämnet, men jag kommer att prata om att det krävs träning av vissa speciella färdigheter för att underlätta denna process. Detta involverar disciplinärt urskiljande samt multidimensionellt tänkande. Jag kommer att beskriva ett teoretiskt ramverk, med praktiska exempel från astronomins värld, på hur detta kan ske.

Learning physics can be compared to learning a new language in several respects. This includes learning to “read and write” the representations that carry the meaning of the language. In the case of physics these representations include text, gestures, mathematics, graphs, images, simulations and animations. For those who are fluent in the language, these representations are full of meaning but for the novice learning to discern the relevant disciplinary aspects of these representations (disciplinary discernment) can be a struggle. Research has shown that often teachers assume that students “see” the same things in a representation that they do. However, this is usually not true. Learning to discern disciplinary aspects of representations is something that students need help with (scaffolding). One important aspect of learning representational fluency in physics is that of spatial thinking, in particular learning to extrapolate three-dimensionality from one- and two-dimensional representations.

In this talk I will present a theoretical framework describing the process of teaching and learning representational disciplinary fluency. I will also provide some examples to illustrate the framework, from the perspectives of the instructor and the student.

Teaching and learning astronomy is known to be both exciting and challenging. To learn astronomy demands not only disciplinary knowledge, but also the ability to discern meaning from disciplinary specific representations (disciplinary discernment). This includes the ability to think spatially, in particular, extrapolating three-dimensionality from a one- or two-dimensional input i.e. to be able to visualize in one’s mind how a three-dimensional astronomical object may look from a one- or two-dimensional input such as from a visual image or a mathematical representation. In this talk I demonstrate that these abilities are deeply intertwined, and that to learn astronomy at any level demands becoming fluent in all three aspects (disciplinary knowledge, disciplinary discernment and spatial thinking). A framework is presented for how these competencies can be described, and combined, as a new and innovative way to frame teaching and learning in astronomy. It is argued that using this framework “Reading the Sky” optimizes the learning outcomes for students. The talk also suggests strategies for how to implement this approach for improving astronomy teaching and learning overall.

Teaching and learning astronomy is known to be both exciting and challenging. To learn astronomy demands not only disciplinary knowledge, but also ability to discern affordances from disciplinary specific representations used within the discourse, which we call disciplinary discernment, and ability to think spatially, which we refer to as extrapolating three-dimensionality from a two dimensional input. Disciplinary knowledge involves all the knowledge that constitutes the discipline, disciplinary discernment involves discernment of the affordances of disciplinaryspecific representations, and extrapolating three-dimensionality involves the ability to visualize in ones mind how a three-dimensional astronomical object may look from a two-dimensional input (image or simulation). In this paper we argue that these abilities are intertwined and to learn astronomy at any level demands becoming fluent in all three. A framework is presented for how these abilities can be described and combined as a new and innovative way to frame teaching and learning in astronomy for optimizing the learning outcome of students - what we refer to as developing the ability to Read the Sky. We conclude that this is a vital competency needed for learning astronomy and suggest strategies for how to implement this to improve astronomy education.

Teaching and learning astronomy is known to be both exciting and challenging. However, learning astronomy at university level is a demanding task for many students. The learning pro-cess involves not only disciplinary knowledge, but also the ability to discern affordances from disciplinary specific representations used within the astronomy discourse, which we call discipli-nary discernment (Eriksson, Linder, Airey, & Redfors, 2014a) and ability to think spatially, which we refer to as extrapolating three-dimensionality from a two dimensional input (Eriksson, Linder, Airey, & Redfors, 2014b). Disciplinary knowledge involves all the knowledge that con-stitutes the discipline, disciplinary discernment involves discernment of the affordances of disci-plinary-specific representations, and extrapolating three-dimensionality involves the ability to visualize in ones mind how a three-dimensional astronomical object may look from a two-dimensional input (image or simulation). In this paper we argue that these abilities are inter-twined and to learn astronomy at any level demands becoming fluent in all three abilities. A framework is presented for how these abilities can be described and combined as a new and in-novative way to frame teaching and learning in astronomy at university level for optimizing the learning outcome of students - what we refer to as developing the ability of Reading the Sky (Eriksson, 2014). We conclude that this is a vital competency needed for learning astronomy and suggest strategies for how to implement this to improve astronomy education.

References

Eriksson, Urban. (2014). Reading the Sky - From Starspots to Spotting Stars. (Doctor of Philosophy), Uppsala University, Uppsala. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234636  

Eriksson, Urban, Linder, Cedric, Airey, John, & Redfors, Andreas. (2014a). Introducing the Anatomy of Disciplinary Discernment - An example for Astronomy. European Journal of Science and Mathematics Education, 2(3), 167-182. 

Eriksson, Urban, Linder, Cedric, Airey, John, & Redfors, Andreas. (2014b). Who needs 3D when the Universe is flat? Science Education, 98(3), 31. 

This talk concerns astronomy eduction resercher and focus on what visualizations offer for learning astronomy at all levels. I will be presenting reserach results concerning disciplinary discernment and spatial thinking in relation to experiences offered by planetarium presentations.

Teaching and learning astronomy is known to be both exciting and challenging. To learn astronomy demands not only disciplinary knowledge, but also ability to discern affordances from disciplinary specific representations used within the discourse, which we call disciplinary dis- cernment (Eriksson, Linder, Airey, & Redfors, 2014a) and ability to think spatially, which we refer to as extrapolating three-dimensionality from a two dimensional input (Eriksson, Linder, Airey, & Redfors, 2014b). Disciplinary knowledge involves all the knowledge that constitutes the discipline, disciplinary discernment involves discernment of the affordances of disciplinary- specific representations, and extrapolating three-dimensionality involves the ability to visualize in ones mind how a three-dimensional astronomical object may look from a two-dimensional input (image or simulation). In this paper we argue that these abilities are intertwined and to learn as- tronomy at any level demands becoming fluent in all three abilities. A framework is presented for how these abilities can be described and combined as a new and innovative way to frame teach- ing and learning in astronomy at university level for optimizing the learning outcome of students - what we refer to as developing the ability of Reading the Sky (Eriksson, 2014). We conclude that this is a vital competency needed for learning astronomy and suggest strategies for how to implement this to improve astronomy education.

When students start to learn physics and astronomy, they immediately are confronted with a multitude of representations packed with disciplinary information. This information is embedded in these representations and the students need to learn to discern the relevant information. This is not straightforward, and requires a lot of teaching and practice before being mastered. It carries many similarities to learning a new language – the language of physics, astronomy, or other sciences. 

However, it all starts with disciplinary discernment from those representations, something that has been shown to be challenging for students. Often the teacher who knows the representations and their appresented meaning—their disciplinary affordances—assumes that the students discern the same things in those representations as the teacher does. Research has shown that this is not the case and such assumptions leads to educational problems for the students and make learning physics or astronomy unnecessary difficult, or even inaccessible to the students. The students need be given the opportunity to develop their competency in discerning disciplinary-specific relevant aspects from representations; a competency referred to as Reading the Sky in an astronomy context, and described by the Anatomy of Disciplinary Discernment (Eriksson, 2014a; Eriksson et al., 2014b).

Furthermore, physics and astronomy are subjects aiming to describe the real multidimensional world, hence involve a substantial amount of spatial thinking. The students need to learn to extrapolate three-dimensionality in their minds from two-dimensional representations, which have been shown to be challenging to students. Unfortunately, this competency is often taken for granted and rarely addressed in teaching (Eriksson et al., 2014c).

In this talk we present a model in which we identify and describe the critical competencies needed to “read” disciplinary-specific representations; it concerns not only disciplinary discernment but also spatial thinking and disciplinary knowledge. These are combined into the Spiral of Teaching and Learning (STL), a new and powerful model for optimizing teaching and learning science (Eriksson, 2014a; Eriksson, 2015). We discuss consequences and possibilities when applying the STL model and give an example of how this model can be used in teaching and learning astronomy.

Aims. To investigate the astrometric effects of stellar surface structures as a practical limitation to ultra-high-precision astrometry (e.g. in the context of exoplanet searches) and to quantify the expected effects in different regions of the HR-diagram. Methods. Stellar surface structures (spots, plages, granulation, non-radial oscillations) are likely to produce fluctuations in the integrated flux and radial velocity of the star, as well as a variation of the observed photocentre, i.e. astrometric jitter. We use theoretical considerations supported by Monte Carlo simulations (using a starspot model) to derive statistical relations between the corresponding astrometric, photometric, and radial velocity effects. Based on these relations, the more easily observed photometric and radial velocity variations can be used to predict the expected size of the astrometric jitter. Also the third moment of the brightness distribution, interferometrically observable as closure phase, contains information about the astrometric jitter. Results. For most stellar types the astrometric jitter due to stellar surface structures is expected to be of the order of 10 micro-AU or greater. This is more than the astrometric displacement typically caused by an Earth-size exoplanet in the habitable zone, which is about 1-4 micro-AU for long-lived main-sequence stars. Only for stars with extremely low photometric variability (< 0.5 mmag) and low magnetic activity, comparable to that of the Sun, will the astrometric jitter be of the order of 1 micro-AU, sufficient to allow the astrometric detection of an Earth-sized planet in the habitable zone. While stellar surface structure may thus seriously impair the astrometric detection of small exoplanets, it has in general a negligible impact on the detection of large (Jupiter-size) planets and on the determination of stellar parallax and proper motion. From the starspot model we also conclude that the commonly used spot filling factor is not the most relevant parameter for quantifying the spottiness in terms of the resulting astrometric, photometric and radial velocity variations.

Traditionally, astronomy and physics have been viewed as difficult subjects to master. The movement from everyday conceptions of the world around us to a disciplinary interpretation is fraught with pitfalls and problems. What characterises a disciplinary insider’s discernment of phenomena in astronomy and how does it compare to the views of newcomers to the field? In this paper we report on a study into what students and professors discern (cf. Eriksson et al, in press) from the same disciplinary semiotic resource and use this to propose an Anatomy of Disciplinary Discernment (ADD) as an overarching characterization of disciplinary learning.

Students and professors in astronomy and physics were asked to describe what they could discern from a simulation video of travel through our Galaxy and beyond (Tully, 2012). In all, 137 people from nine countries participated. The descriptions were analysed using a hermeneutic, constant comparison approach (Seebohm, 2004; Strauss, 1987). Analysis culminated in the formulation of five hierarchically arranged, qualitatively different categories of discernment. This ADD modelling of the data consists of one non-disciplinary category and four levels of disciplinary discernment: Identification, Explanation, Appreciation, and Evaluation. Our analysis demonstrates a clear relationship between educational level and the level of disciplinary discernment.

The analytic outcomes of the study suggest that teachers may create more effective learning environments by explicitly crafting their teaching to support the discernment of various aspects of disciplinary semiotic resources in order to facilitate the crossing of boundaries in the ADD model.

Learning astronomy has many learning challenges due to the highly diverse, conceptual, and theoretical thinking used in the discipline. One taken for granted challenge is the learning to 

extrapolate three-dimensionality. Although we have the ability to see our surroundings in three- dimensional terms, beyond a distance of about 200m this ability quickly becomes very limited. So, when looking up at the night sky, learning to discern critical features that are embedded in dimensionality does not come easily. There have been several articles addressing how fruitful 3D simulations are for astronomy education, but they do not address what students discern, nor the nature of that discernment. Taking the concept of discernment to be about noticing something and assigning meaning to it, our research question is: In terms of dimensionality, what do astronomy/physics students and professors discern when engaging with a simulated video fly- through of our Galaxy and beyond?

A web-based questionnaire was designed using links to video clips drawn from a well-regarded simulation-video of travel through our galaxy and beyond. 137 physics and astronomy university students and teaching professors, who were drawn from nine countries, completed the questionnaire. The descriptions provided by them were used to formulate six categories of discernment in relation to multidimensionality. These results are used to make the case that astronomy learning that aims at developing the ability to extrapolate three-dimensionality needs to be grounded in the creation of meaningful motion parallax experiences. Teaching and learning implications are discussed. 

Learning astronomy has exciting prospects for many students; learning about the stars in the

sky, the planets, galaxies, etc., is often very inspiring and sets the mind on the really big

aspects of astronomy as a science; the Universe. At the same time, learning astronomy can be

a challenging endeavor for many students. One of the most difficult things to come to

understand is how big the Universe is. Despite seeming trivial, size and distances, together

with the three-dimensional (3D) structure of the Universe, probably present some of the

biggest challenges in the teaching and learning of astronomy

(Eriksson, Linder, Airey, &

Redfors, in preparation; Lelliott & Rollnick, 2010). This is the starting point for every

astronomy educator. From here, an educationally critical question to ask is: how can we best

approach the teaching of astronomy to optimize the potential for our students attaining a

holistic understanding about the nature of the Universe?

Resent research indicates that to develop students’ understanding about the structure of the

Universe, computer generated 3D simulations can be used to provide the students with an

experience that other representations cannot easily provide (Eriksson et al., in preparation;

Joseph, 2011). These simulations offer disciplinary affordance* through the generation of

motion parallax for the viewer. Using this background we will present the results of a recent

investigation that we completed looking at what students’ discern (notice with meaning)

about the multidimensionality of the Universe. Implications for astronomy education will be

discussed and exemplified.

*[T]he inherent potential of [a] representation to provide access to disciplinary knowledge

(Fredlund, Airey, & Linder, 2012, p. 658)

Eriksson, U., Linder, C., Airey, J., & Redfors, A. (in preparation). Who needs 3D when the

Universe is flat?

Fredlund, T., Airey, J., & Linder, C. (2012). Exploring the role of physics representations: an

illustrative example from students sharing knowledge about refraction. European

Journal of Physics, 33(3), 657.

Joseph, N. M. (2011). Stereoscopic Visualization as a Tool For Learning Astronomy

Concepts. (Master of Science), Purdue University, Purdue University Press Journals.

Lelliott, A., & Rollnick, M. (2010). Big Ideas: A review of astronomy education research

1974--2008. International Journal of Science Education, 32(13), 1771–1799

Vertical amusement rides let your body experience the tickling sensation of feeling light, but also feeling much heavier than as usual, due to velocity changes as you move up and down. Family rides offer different possibilities to visualize the forces that are experienced by your accelerating body. This paper presents a number of different ways to view and experience the motion in a small vertical amusement ride. A smartphone includes an accelerometer that can provide a graph of the forces acting during the ride. A movie from the smartphone camera lets students recall the motion which can then be analysed in more detail. The complementary representations may help students develop a deeper understanding of the relation between force and motion. The affordances of these different semiotic resources are analysed in some detail. In addition, we discuss responses from a number of students to questions about where you feel light and where you feel heavy. We find that the experience of the body is an underused resource in physics teaching.

Vertical amusement rides let your body experience the tickling sensation of feeling light, but also feeling much heavier than as usual, due to velocity changes as you move up and down. Family rides offer different possibilities to visualize the forces that are experienced by your accelerating body. This paper presents a number of different ways to view and experience the motion in a small vertical amusement ride. A smartphone includes an accelerometer that can provide a graph of the forces acting during the ride. A movie from the smartphone camera lets students recall the motion which can then be analysed in more detail. The complementary representations may help students develop a deeper understanding of the relation between force and motion. The affordances of these different semiotic resources are analysed in some detail. In addition, we discuss responses from a number of students to questions about where you feel light and where you feel heavy. We find that the experience of the body is an underused resource in physics teaching.

This paper aim at investigating what astronomy students and experts discern from the multitude of different disciplinary affordances available in Hertzsprung-Russell (HR) diagrams. HR-diagrams are central to all of astronomy and astrophysics and used extensively in teaching. However, knowledge about what students and experts discern from these disciplinary representations are not well known at present. HR-diagrams include many disciplinary affordances that may be hidden to the novice student, hence we aim at investigating and describing what astronomy students at different university levels (introductory, undergraduate, graduate), and astronomy educators/professors, discern from such representation – referred to as disciplinary discernment (Eriksson, Linder, Airey, & Redfors, 2014). Data from a web based questionnaire were analysed using the Anatomy of Disciplinary Discernment (ADD) framework by Eriksson et al. (2014). Preliminary results show (1) the developmental nature of disciplinary discernment from the HR-diagram by the participants and (2) the large discrepancy between disciplinary discernment by the astronomy educators and their students. We describe and discuss the qualitative nature of these differences and how this can have implications for teaching and learning astronomy.

This paper aim at investigating what astronomy students and experts discern from the multitude of different disciplinary affordances available in Hertzsprung-Russell (HR) diagrams. HR-diagrams are central to all of astronomy and astrophysics and used extensively in teaching. However, knowledge about what students and experts discern from these disciplinary representations are not well known at present. HR-diagrams include many disciplinary affordances that may be hidden to the novice student, hence we aim at investigating and describing what astronomy students at different university levels (introductory, undergraduate, graduate), and astronomy educators/professors, discern from such representation – referred to as disciplinary discernment. Data from a web based questionnaire were analysed using the Anatomy of Disciplinary Discernment (ADD) framework by Eriksson et al.(2014). Preliminary results show (1) the developmental nature of disciplinary discernment from the HR-diagram by the participants and (2) the large discrepancy between disciplinary discernment by the astronomy educators and their students. We describe and discuss the qualitative nature of these differences and implications for teaching and learning astronomy.

Learning astronomy at higher level can be both exciting and challenging. Entering the discipline of astronomy involves learning the way that astronomers communicate knowledge, using a multitude of disciplinary specific semiotic recourses to understand the multidimensional universe. A new-to-the-discipline student will need to learn to “read” and “write” all these resources in her endeavour to learn astronomy and become part of the discipline. In this paper, we present a study where university students and professors are presented by different 2D and pseudo-3D resources—representations of astronomical objects—and asked about how these objects may look in 3D, i.e. we ask them to extrapolate three-dimensionality from 2D inputs. These inputs are 2D pictorial representation and world-class 3D rotating volumetric models presented on flat screens. Data were collected using a web-based questionnaire from 53 participants in four different countries. From the results, we find that all participants struggle to find cues for depth perception in the 2D pictorial representations. As could be expected, the student participants were much worse in doing so than the astronomers, but with one exception: students used the offered motion parallax as their main cue when this was available. The astronomers used many cues in their struggle to perceive depth but surprisingly did not use the presented parallax motion to a large extent. We interpret this as follows: for the students, they lack the knowledge to use disciplinary cues and used the only cue that they know from experience, namely, parallax motion. For the astronomers, they used a multitude of disciplinary cues based on their extensive disciplinary knowledge, and did not find the new cue, motion parallax, as useful as the ones that they were used to use. In this paper, we present and discuss these results and its implication for teaching astronomy.

The distribution of the Gamow–Teller (GT) β⁺ strength is estimated for both oblate and prolate Hartree–Fock (HF) local minima for even-even nuclei with 62 ≤ Z ≤ 70 near the proton drip line, using the quasiparticle Tamm–Dancoff approximation (TDA) based on a deformed HF + BCS calculation with Skyrme interaction. The prolate local minima and the oblate local minima lie energetically close for these nuclei. Almost all the GT strength lies below the ground state of the mother nuclei in this region. The GT strength distribution is not sensitive to deformation. For the isotones N = 74 and N = 76 close to the proton drip line the total GT strength is always larger for the prolate shape than the oblate shape. Approaching the proton drip line the total GT strength increases.

What factors influence Swedish upper secondary teachers' laboratory teaching in physics? This is an issue raised by the curriculum reform of 2011 in Sweden. In this study, 17 teachers at four different upper secondary schools discussed their laboratory teaching in focus group interviews. Based on an analysis of these interviews, a supplementary survey of 66 teachers was conducted. Logic of events was used as an analytical tool to understand how different factors influence teachers' teaching. The results from the focus groups indicate that teachers appreciate laboratory work that 1) are based on simple equipment, 2) provide good values of constants, 3) laboratory exercises that the students like. In the survey, the syllabus emerged as a stronger factor of influence than in the focus groups – but, the results from both parts indicate that other factors than the syllabus play a larger role for teachers' choice and layout of laboratory work.

Experiments have a long tradition in physics teaching and there are many examples of classical school experiments. At the same time laboratory teaching is affected by curriculum changes and technological development. In this study experienced teachers at three different upper secondary schools discuss their laboratory teaching. The analysis is based on the logic of events. The study provides insight into factors affecting teachers’ teaching and how classical experiments are adapted and challenged by new conditions. The results indicate that tradition is a stronger factor of influence than policy documents, in particular when very limited time is allowed for professional development.

This chapter addresses the challenges and potential of implementing formative assessment in higher education with a specific focus on astronomy. We emphasize the use of formative assessment strategies as a coherent whole and a learning environment that encourages student autonomy and divergent thinking.

Non-traditional examples can be very inspiring for students. This paper applies classical mechanics to different ways of skating in ice hockey.&amp;#13; Skating blades glide easily along the ice in the direction of the blade. Horizontal forces on the skates are thus essentially perpendicular to the blade. Speed skaters glide long distances on each skate before pushing off for the next stride. A hockey player running for the puck may take a number quite short steps in a short explosive rush before shifting to longer strides, where the recurring need to change direction requires additional work by the skater. This paper investigates an alternative stride, with a longer gliding phase in a circular arc, where the centripetal force provided by the ice acting on the skates, changes the direction of motion, without the need for additional energy. In addition, the conservation of angular momentum leads to increased speed as the centre of mass is shifted closer to the centre of the circular arc.&amp;#13; Finally, we discuss an angular momentum based technique to reverse the direction of motion as fast as possible.

Att ha en förståelse för hur ljud och ljus beter sig gör att man kan förklara ett antal olika fenomen i vardagen. Optik och akustik har stor betydelse, såväl ekonomiskt som för livskvalitet, genom t.ex. glasögon och hörapparater. Det är även möjligt att undersöka kroppens inre genom ultraljud eller med "endoskop" och fiberoptik. Optik ingår bl.a. i foto- och videoteknik och i CD-spelare. Intensiv forskning utvidgar hela tiden användning av optik inom medicin, mätteknik och informationsteknologi. Boken är avsedd för grundläggande högskolestudier i optik och vågrörelselära. Den innehåller övningsuppgifter i riklig mängd, i form av diskussionsfrågor, laborativa uppgifter och problem.

Students often find astronomy and astrophysics to be most interesting and exciting, but the Universe is difficult to access using only one's eyes or simple equipment available at different educational settings. To open up the Universe and enhance learning astronomy and astrophysics different planetarium software can be used. In this article we discuss the usefulness of such simulation software and give four examples of how such software can be used for teaching and learning astronomy and astrophysics.

We discuss different excitation processes behind the Fe II emission lines in the IUE spectrum of KQ Puppis (Boss 1985), a VV Cephei type of spectroscopic binary. Several pa pers have been published on the subject suggesting a number of processes behind the strong Fe II emission lines. We propose that there are two processes operating: selective photoexcitation by continuum radiation (PCR) from the B-star companion, and photoexcitation by accidental resonance (PAR) by the H Ly alpha radiation field. We suggest excitation channels for each of the Fe II emission lines identified in the spectrum.

The Fourier-transform spectrum from an iron-neon hollow-cathode lamp has been studied in the region 9000-11 000 Å. The 3d⁶(⁵D)5g subconfiguration of Fe II has been established by means of about 220 newly identified 4f-5g transitions. The 5g configuration is well represented by J K coupling, which is demonstrated by the application of the quadrupolic approximation. A consistent pattern in the FWHM for various types of Fe II transitions has been observed. Calculated oscillator strengths are given for all observed lines and their relative accuracy is estimated from observed intensities. The new data offer unprecedented tools for diagnostics of stellar atmospheres.

Various alternative models were used to describe the structure of 106Ru . For example, the General Collective Model (GCM) predicts shape-coexistence for 106Ru with a spherical and a triaxial minimum and strongly mixed structures, while in the IBA-2 calculations, where 106Ru was considered as transitional from vibrational U(5) to γ -soft O(6) , no need was found to include the shape-coexisting configurations. In order to provide additional constraints on the model interpretations, we have applied the Advanced Time-Delayed (ATD) βγγ(t) method to measure the level lifetimes of the excited levels in 106Ru . The new results include the half-lives of T 1/2 = 183(3) ps and 7.5(30)ps for the 2+ 1 and 2+ 2 states, respectively.

Programming as a tool to be used for analysing and exploring physics in an educationalsetting offers an unprecedented opportunity for the students to create and explore their ownsemiotic resources. Students may use programming to create and explore different models ofphysical systems. In this study a small group of upper secondary education students participatedin a workshop where they learned to program physics simulations and to create their own modelsto implement using the programming language Python. Results from the study shows thatupper secondary education students are able to create their own models of physical systemsand implement them into code. The implemented models were models of hanging cloth andheat diffusion. Results were obtained by analysing video and audio recordings of the studentsthrough the lens of social semiotics.