Transcript CubSat Exploration

CubSat Exploration
A plan for finding new exoplanets in
the Beta Pictoris system
The Target: Beta Pictoris
Artist's conception of the planet-forming disk around the
star Beta Pictoris. The carbon-rich gas disk is fed by the
debris from small colliding bodies and the evaporation
of comets. Credit: NASA / FUSE / Lynette Cook
 Beta Pictoris is a fourth
magnitude star, with a
distance of 63.4 light years
and an age of only 8–20
million years.
 The star itself is 1.75 times
as massive and 8.7 times
as luminous as our Sun,
making it a fourth
magnitude star.
 The star is surrounded by a
debris disk, which is edgeon to our observations from
Earth, making it easier to
study the contents of the
disk itself.
The Planet: β-Pic B
 The European Southern Observatory
confirmed the presence of a planet
orbiting within Beta Pictoris' disk.
 This was done through the use of direct
imaging — a usually difficult method to
use when it comes to exoplanets.
 Beta Pic b has a mass between 4 and
11 Jupiter masses and a radius about
65 percent larger than Jupiter's. The
planet orbits at a distance of 9 AU from
the star Beta Pictoris, with a low
eccentricity and a period of roughly 20
years. In comparison, Bets Pic b’s orbit
is just under the size of Saturn’s around
our own sun.
The Plan: Transit Photometry
 Since the debris disk around Beta
Pictoris is edge-on and not too
dense we can easily observe
objects that pass in front of the star
 By measuring the light curve we
can potentially see dips in the star’s
brightness when a planet passes in
front of the star
 Any dip in the curve must be at
least three times the noise (sigma)
in the stellar brightness
measurements
 We will calculate for detection of at
least 3 sigma
The Parameters: Our Formulas
 Transit Depths - The percentage of light
blocked by the planet passing in front of the
star is proportionate to their relative sizes
 Scatter Noise - The noise must be no more
than a third of the transit depth to be
detected and acknowledged as a planet
 Number of Photons - To reduce the noise of
the star we must collect a certain number of
photons
 Time for Detection - The time needed to
collect the number of photons given the
stellar flux and efficiency of the telescope
 Semi-Major Axis - Assuming that the
cubesat lasts a year we will be looking
within a distance of 0.597 AU
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)
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The Results: We Can Detect New
Planets
 This graph gives us
our measure of 3
sigma for a planet
of a certain size
Results Cont.
 This graph tells us
how many photons
will reduce the
stellar noise
enough to see the
dip
Results Cont.
 This graph tells us
hoe long our
cubesat will have
to observe in order
to make accurate
detections
The Future: Next Steps
 The next step will
be designing an
instrument that can
achieve the
requirements we
have set.
 We will have to
either buy or
develop a
telescope and
detector with the
precision to detect
planets of at least
Neptune size up to
Super Jupiters.
The NAC Program
My experience with my peers and mentors
The Mentor: Dr Aki Roberge
 I had the pleasure of working with
Dr. Aki Roberge, a NASA scientist
at the Goddard Space Flight
Center
 Her fields of study are Exoplanets
and Stellar Astrophysics
 She received her B.S. in Physics
at Massachusetts Institute of
Technology, her M.A. in Physics at
John Hopkins University and her
PhD in Astrophysics at John
Hopkins University
 Her thesis was on Ultraviolet
Spectroscopy of Circumstellar
Disks
The Peers: My Dear Friends
 One great aspect of the
NAC program is that we
have a group of other
students to converse,
grow and bond with.
 Every week we would
meet up for project
updates and to discuss
which events we would
be attending.
 Having a group of peers
helps with feeling more
accepted in the
internship. Makes it a
safe place.
The Fun: Our Trips and Experience
 We also had the
pleasure of taking trips
around the area and
being involved in many
events over the summer.
 We attended the Young
Astronomers meeting at
Catholic University, the
Indigenous Youth Day
Science Fair, and took a
tour of University of
Maryland College Park
and their new Astronomy
building.