Explore the Universe:A Further Look Into Imaging Exoplanet Transits

Elizabeth Duongeduong1@umd.eduBiological Sciences

Introduction

Imaging

ConclusionsObservation Prep

Findings

We would like to acknowledge UMD Observatory Director, Elizabeth Warner, Dr. Alan Peel, and the SDU Scholars Program

The Explore the Universe Capstone features a partnership with the UMD

Observatory to observe exoplanet transits. After imaging the transits, we then process and calibrate the images

to analyze the transit data.Exoplanets are planets outside our solar system. A transit is when an

object within a star’s orbit blocks our view of the star, causing a decrease in detected brightness from the star. This

dip in brightness is useful in understanding information about the

exoplanet itself.

In order to actually find our stars we are suppose to observe, we need to

sync onto nearby stars and use coordinates for the star, but often still need manual adjustments to find our

stars. Once we find the star we are observing, we set up the telescope to track an easily visible star so that the telescope stays with the star as the

Earth rotates. Now that tracking is on, we can have the telescope take

hundreds of images until the transit ends. Before we are done for the

night, we need to take darks, biases, and flats, which are images that help

with calibrating our camera to remove background noise and hot/cold pixels.

Before we can observe we have to check with the Exoplanet Transit

Database (ETD) to know when and where transits are occurring during the night. Transits can be anywhere

from half an hour to 6 or 7 hours long. Along with the times and the location

in the sky of the transit, ETD also gives us an image of the sky chart,

allowing us to find the star by noticing patterns in nearby stars. With all the information form ETD, we can

begin observing.

The goal of this research project wasto be able to display a light curve of an exoplanet transit. However, in the

process, we learned different astronomical tools such as using a telescope, calibrating images, data

processing, and utilizing differential photometry skills through new and

various software. This was meaningful to us because it provided

a hands on experience with work that would never be available

outside of the field of astronomy.

Once we have our images, we employ the software AstroImageJ (AIJ). This processing software allows for us to combine our calibration frames into master images for each, which help

cancel out various noise in the “science” images. By comparing the

brightness of our target to itself and nearby stars as the software cycles

through our transit images, it creates a graph showing the brightness of

our target as time passes, resulting in a light curve highlighting the exoplanet passing by the star.

Ethan Kramerethankrm@gmail.comAerospace Engineering

Science, Discovery, and the Universe

Ethan and Elizabeth at the observatory with the 7” AP Refractor telescope (Dec 4, 2018)

A screenshot of the Exoplanet Transit Database and its related information

The graph of the recorded light curve ofexoplanet XO-2B transit, including reference stars

A screenshot of the software AstroImageJ while processing transit recorded data