Part 3: Detecting Alien Worlds

xo1-finding

You should have a number of images of a star that has a suspected or confirmed exoplanet orbiting it. The images should be timed to occur at roughly the time the planet is expected to pass in front of the star.

Find the star in your images and create a light curve for it using Maxim DL. If you timed your observation well, and made your lightcurve measurements properly, you should see a dip in the lightcurve as in the image at right. Using the lightcurve and your conclusions from the previous sections, determine:

•аThe maximum and minimum flux

•аThe exact date and time of the center of the eclipse. This information can be helpful to astronomers in determining the planet's mass and distance from the parent star!

•аThe relative radius of the planet with respect ot the star, using the relationship determined in Part 2.

With the spectral type of the star, you can estimate the star's actual radius and mass by making the (likely) assumption that it is on the main sequence. Using this information, what is the radius of your exoplanet? How does this compare to the size of planets in our solar system?

Guideposts

•аThe light sensor in Part 2 measures changes in brightness in terms of units of flux, but in the sky or an astronomical image brightness differences are measured in magnitudes. To convert from magnitudes, which are logarithmic, to a brightness ratio, use the following formula:

eqn1


ай 2016 University of Iowa