Schools Observe Variable Star and Asteroid Light Curves

For the last few weeks, LCOGTN have been developing photometry techniques that are easy to follow, and make use of free software that is easily available to teachers and students. A number of schools have been involved in observing variable stars and carrying out photometry to see if they can obtain a light curve from the results.

Photometry is a method by which you measure the intensity (or brightness) of the electromagnetic radiation emitted or reflected by an object.

A light curve is a plot of the change of intensity against time and can tell you much about the physical properties of the object in question.

After some failed attempts to obtain a light curve of a variable star, we went back and looked at other ways of doing the measurements, and tried various pieces of software in the process. The aim all along was to obtain a method of measuring the light curves of objects whose brightness varies, using free software that is accessible to school students. On Friday 12th October we managed to do this.

You can find out more about the process we went through by following the work done in our online training group.

With help and suggestions from both the amateur and professional astronomy communities, we successfully obtained a light curve for the star NSV 855. Four schools made their own observations of the same star and we were able to re-create part of a light curve we had obtained elsewhere to confirm our method worked correctly.

NSV 855 from Roger Pickard

NSV 855 from FTN

The asteroid light curves we created using data previously taken as part of a themed observing day back in June, the asteroids observed were 216 Kleopatra and 1997 QD2.

Now that we have the photometry technique sorted out, there will be many more opportunities for schools to take part in themed observing days to create light curves of more variable stars and asteroids.

The following schools took part in helping develop this photometry technique for variable stars and rotating asteroids:

Blundell's School

Clifton High School

Glenlola Collegiate

Highgate School

Light Hall School

The Avon Valley School

The Kings School, Canterbury

The Kingsley School

Monmouth School

Norton Knatchbull School

Radley College

Simon Langton Grammar School for Boys

West Monmouth School

Whitchurch High School

We would like to thank Dr Tim O'Brien (Jodrell Bank Observatory) and Roger Pickard (Director, British Astronomical Association Variable Star Section) for their helpful suggestions. We would also like to thank Roger for allowing us to use his data and measurements with schools.