Hunting in the X-ray Sky, an Inquiry-based Learning Activity

We explicitly adopt an Inquiry-based learning strategy, together with a peer-to-peer education approach. This global strategy both fosters the critical thinking and engages the students, who act as they were researchers.

A short but clear framework for describing inquiry in astronomy is provided by the IAU project astroEDU. The workshop should be run in a very informal environment. The students should be divided into small groups of 3-4 people.

The first part of the workshop is addressed to engage them in contemporary astrophysics, with a specific regard to the high energy band. Researchers or teachers introduce them to the contents and the technical language of astronomy (as field of view, electromagnetic spectrum, time resolution, space resolution and energy resolution, light curve, photons and so on) and mathematics (such as probability, confidence level and so on). At this stage, researchers and teachers should try to avoid a trivial “top-down” approach. They are requested to solicit questions and discussion about topics, instead of acting as pure experts. On the other hand, the goal of this part is to give students the right method and conceptual tools to face the data reduction and interpretation, so that some kind of passive learning has to be taken into account by the students.

The second part of the workshop is addressed to allow the students to analyse data from EXTraS. They use the EXTraS software to verify if a candidate source is a real transient. This is made mainly by studying its light curve. If the validation is successful, the students should wonder if the X-ray source is a brand new one or an old acquaintance. In the latter case, it should be present in some other X ray archives. They also should wonder if it has a known counterpart in different wavelengths. The can try to match their “new” EXTraS catalogue transient with some other sources in the same position listed in multi-wavelength catalogues on-line. This allows them to “stop-and-try to guess” their transient source.

The leading questions of our inquiry are the following, each of them representing a step for further investigation of the data:

The five questions

  1. Is the transient candidate a real transient X-ray source?
  2. Is it a new X-ray source?
  3. Does it have a possible counterpart at other wavelengths (e.g. optical)?
  4. What kind of astrophysical object or phenomenon might it be?
  5. Might it be an important scientific discovery?