Help NASA observe distant worlds around other stars!

EXOTIC software exampleSearching for the shadows of exoplanets is known as the transit method: capturing the tiny dips in starlight as a planet passes in front of its star. Of the thousands of exoplanets confirmed in our galaxy so far, most have been found by watching for planetary transits. To confirm a planet’s existence, scientists typically want to observe a transit more than once. Doing so can reveal properties of the planet – its diameter or the length of its year (the time it takes to make one orbit around its star). Exoplanet Watch seeks to confirm these repeated transits, but predicting the next transit can be difficult. The timing of transits is poorly known for many potentially interesting targets.

The project offers participants regular updates about stars that require additional observations, as well as likely transit times, which participants help refine. They will also receive user-friendly instructions about how to upload data to our processing software.

These observations will pave the way for professional astronomers to turn their powerful instruments to the same planets.


The EXOTIC (Exoplanet Transit Interpretation Code) software allows observers to input their data. EXOTIC then converts it into light curves, graphs that show the brightness of an object over a period of time – and the bread and butter of exoplanet hunters. As a planet begins to move across the face of a distant star, the corresponding light curve begins as a flat line. Then it takes a sharp dip as the planet moves toward the star’s center and blocks a tiny percentage of the star’s light. As the planet moves past the star’s face, the line rises again to its formerly flat position. The resulting wavy line is the planet's light curve. The larger the planet, the more starlight it blocks. Wait for a second dip, as the planet comes back around, and you know the length of the planet's year – one trip around the star.


Exoplanet Watch