Angelos Mengoudis View / Download CV
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Year
2024
Context
Two-student group, supervised by Ioannis Gkolias
Built with
HOPS, relative photometry

Visit ExoClock ↗

You don't need to be a professional astronomer to contribute to real exoplanet research. A small telescope, a camera and some careful work are enough.

Why exoplanets need a clock

When a planet passes in front of its star, it blocks a little of the starlight. This is a transit. Transits repeat with every orbit, so we can predict the next one, but the uncertainty on those predictions grows over time.

Space telescopes such as ESA's Ariel, which will study about 1000 exoplanets, need to point at the right planet at the right moment. ExoClock keeps those predictions up to date with new observations from small and medium telescopes, including ones run by members of the public.

A planet crosses in front of its star. Below, the star's measured brightness dips while the planet covers part of it. brightness time
Schematic transit, not real data. The dip is exaggerated: a real one is usually around 1% or less.

What we did

This was my first hands-on work with exoplanets. In a group of two students, we observed a star during a known exoplanet transit. We analysed the images with HOPS, using relative photometry: the target star is measured against comparison stars in the same images, so changes in the sky affect them all equally and only the transit stands out. We then submitted the light curve to ExoClock.

It works

ExoClock's latest catalogue combined about 30,000 measurements to update the predictions for 620 exoplanets, and 45% of them needed an update. Anyone who contributes to a data release, even with a single observation, becomes a co-author of the paper.

How to take part

  1. Register your telescopeAny telescope with a CCD or CMOS camera.
  2. Get your scheduleA personal list of transits you can observe.
  3. Observe a transitImage the star before, during and after it.
  4. Analyse the imagesMake a light curve, for example with HOPS.
  5. Upload itThe team reviews it and adds it to the database.

Full instructions are on ExoClock's "Contribute" page.

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