The Astronomy Laboratory

A Cassini image of Jupiter and Ganymede

aims and objectives

1. to foster an appreciation of the interplay between theory and experiment (or observation) in scientific work;
2. to develop your skills in data analysis, including the ability to estimate, and manipulate in calculations, experimental uncertainties;
3. to develop your skills in communicating and presenting scientific results.

These aims are different from, and complementary to, the aims of the lecture courses, which are primarily designed to impart knowledge of the subject, and those of the tutorials, which are intended to help you develop your problem solving skills. All three components are therefore needed if you are to acquire the knowledge and skills expected of a scientist in general, and an astronomer in particular. We do, however, do our best to ensure that the laboratory exercises in astronomy and astrophysics relate to the taught material, so in semester 2 you will be doing exercises related to the material of PHY104 Introduction to Astrophysics. In semester 1, the astronomy component of PHY115 is a stand-alone course on positional astronomy, which is intended to equip you with the knowledge and skills necessary to perform astronomical observations using a telescope.

organisation

The organisation of the laboratory work depends on your degree programme. Physics and Astrophysics students need to master laboratory and observing techniques relevant to both astronomy and physics, whereas Mathematics and Astronomy students are specifically interested in astronomical techniques.

For Physics and Astrophysics students, the laboratory component of your first year includes the following sections:

Semester 1:

• three skills experiments intended to familiarise you with basic physics laboratory equipment and techniques (3 of weeks 1-4);
• one computing session introducing standard computer packages that you will use throughout your degree (1 of weeks 1-4);
• one formal laboratory report that you will write based on one of the skills experiments;
• one observational practical using the Department's robotic telescope, which you will carry out after completing the Positional Astronomy course in the second half of the semester.

Semester 2:

• three astronomy laboratory exercises which are intended to develop your skills in analysing astronomical data, with particular emphasis on your skills in using relevant software packages;
• three physics "pool" experiments intended to further develop your skills in carrying out experimental work in a physics laboratory setting;
• one formal laboratory report, to be based on any of the astronomy or physics pool experiments;
• two lab sessions on AC circuits, to develop an understanding of the fundamental principles and behaviour of electrical equipment.

The exact schedule of the semester 2 course (which varies from year to year owing to the fact that the Easter vacation dates change) will be announced at the beginning of semester 2.

The work in semester 1 is assessed as part of module PHY115, and the second semester work as PHY116.

assessment

PHY115 and PHY116 are "portfolio" style modules covering a range of topics delivered and assessed in a variety of different ways. Each component — short courses, lab work, workshops, homework exercises — addresses different essential components of the skill set of a professional scientist. You are therefore required to pass each component of the assessment separately in order to pass the module as a whole. Of course, this does not mean that you have to pass every single thing: like is grouped with like, so that, for example, all three skills experiments in PHY115 are combined as one component of your portfolio.

These are relatively new modules, and the relative weights of the different components are still undergoing fine tuning. The draft assessment schemes are as follows:

Homework exercises and formal lab reports are handed in to the Departmental Office. As with most assessed assignments, you will be required to download a personalised coversheet, which includes your registration number but not your name, from the Departmental website. This is in line with the University's Students' Charter, which states that "wherever practicable and appropriate, departments will ... seek to ensure the anonymous marking of non-invigilated examinations." The idea is to prevent the marker's preconceived ideas about particular students from affecting the marks awarded. This is not very important for most work in physics and astronomy (where answers are generally right or wrong) but may be significant in assessing lab reports (where there is a certain amount of subjectivity). The lab exercises are not marked in this way because the personal contact with the demonstrator is intended to help you to improve your skills in a way that anonymous marking out of the lab could not.

You will note that the laboratory work includes one formal laboratory report, contributing 20% to the total module grade. The aim of this exercise is to introduce you to the art of communicating your scientific results to other scientists. You may choose to write up any of your completed assignments, but

• choose one that has been marked (if the one you want to use hasn't been marked yet, take it to a demonstrator and ask) – this is to make sure that you do not lose unnecessary marks by writing up an assignment which you did not properly understand;
• choose one that went well, or where you fully understand what went wrong (in a report, you must explain any discrepancies between your results and standard values, so choosing one that went wrong for reasons you don't understand is asking for trouble);
• fix any known problems (if the demonstrator told you that you had calculated your uncertainties incorrectly, recalculate them; if you were told that your plot would be more informative with a different scale, remake it) – again, there is no point in losing marks twice for the same fault;
• read the report writing guidelines, and choose an assignment that fits well into the standard report style (some work better than others, and if you are inexperienced in writing reports it is better to choose an assignment that converts easily).

Many students find this task very difficult, and there will be a Scientific Writing Workshop in Semester 1 to help you to prepare. Guidance notes and examples are also provided: read these carefully and ask someone if you are confused or uncertain. (Note the differences between the example report and the corresponding lab diary: a report is not just a word-processed version of your lab book!)

Please note that poor grammar and spelling will be penalised; if your written English skills are not up to the task, consult the University's Writing Advisory Service for help. Do take this task seriously — the ability to write a clear, concise, well-structured report in grammatically correct formal English is one of the most important transferable skills you will acquire in your entire degree.

Formal lab reports are marked according to the following scheme:

Note that appropriate allowance will be made for students who have been diagnosed as dyslexic, or whose first language is not English, if we are advised of the fact: please attach a note to the cover sheet explaining the problem. Both dyslexic students and those who are not native English speakers are strongly advised to make use of the Writing Advisory Service.

As with all written work, copying material from sources other than your own lab diary (such as the script, other students' diaries or reports, textbooks and lecture notes) is strictly forbidden. You may use information (e.g. the true value of the mass of Jupiter) from other sources, provided that the source is properly referenced, but other people's exact words are always off limits. Please read the Departmental guidelines on plagiarism and collusion before handing in your report, and check that it complies.