Download PHY299B Poster-Justin Hudson-v2

78 Tau, Eclipsing Binary Star
Justin
1
1
Hudson ,
Elizabeth
2
Warner
2
UMD Physics, UMD Astronomy
Telescope Operation
Goals of This Project
• To observe an eclipsing binary star in this case
78 Tau.
• Gather pictures of the eclipsing binary star
throughout its phase.
• Use software (AstroImageJ) to analyze the
luminosity of the target star and to graph the
luminosity verses time.
Background Information
• An eclipsing binary star is a star that orbits
another star, that when one begins to move in
front of the other, it blocks the light which is
visible from Earth.
• 78 Tau is in the Taurus constellation with a
brightness magnitude of 3.35-3.41 and a period
of 0.07564 days (1.84 hours)¹.
Picture of 78 Tau, what it actually looks like in the night sky²
• Using the UMD Observatory 6 and 7inch
telescopes, with CCD cameras to gather images
we must first cool the CCD cameras for at least
2 hours.
• Following cooling, taking flat images of the sky
slowly getting darker as day turns to night to
help clean up our images that could be altered
by dust or other things interrupting the light
coming into the telescope.
• Once it is night, calibration of the telescope,
then focusing on a star that is easily identifiable.
This lets the computer running the telescope
where in the sky it is looking and to take clear
pictures.
• With this done, we type in the coordinates to the
target star. We must use the star map to find the
target star, center it, then set a series of pictures
over time and let the telescope collect our data.
Expected Results
• If everything would have gone as planned, we
would have produced a light curve as seen to
the bottom picture.
• What this light curve shows is that the deepest
dips in brightness during the phase is when the
brightest star is blocked by the other creating
the eclipsing effect like when Earth experiences
a solar eclipse. The smaller dips in brightness is
when the brighter star blocks out the light from
the other star when passing in front of it.
• From these curves, we can tell if stars follow the
characteristics of an eclipsing binary or other
types of variable stars.
Setbacks
Star map of 78 Tau with other identifying stars in the sky³
• Due to poor weather conditions in the late
winter/early spring, all attempts to observe were
ruined by clouds, rain or snow.
• Even though the weather prevented data
collection, the telescope operation skills that
were acquired prove to be very valuable to star
gazing and examining the night sky.
References
1. AAVSO, The International Star Index, 2009
2. SIMBAD, Astronomical database,
3. Stellarium, Planetarium, March 2015
4. www.physics.sfasu.edu, Binary Star Lecture
Sponsored by the Department of Physics, University of Maryland, College Park