Graduate seminar on topical areas in modern astrophysics and
cosmology. Each semester a different topic of current special
interest is selected. Participants in this seminar discuss papers
given by seminar members (in rotation). Several faculty members also
participate.
Note: Participation for three semesters is required to obtain
credit for this course.
Extrasolar
Planets - page by Dimitar Sasselov
Extrasolar Planet
Detection at CfA
University of California Planet Search
Project
This page was last updated on Tue Dec 14 16:10:41 EST 2004
Preliminary Schedule for Fall'2004:
"Organizational meeting" -
Matt Holman,
Dimitar Sasselov and
Kris Stanek
0. September 22, 2004Abstract:
How the course is organized. Motivation for the topic. Scheduling the
talks.General reading material for the Semester:
Related links:
The Extrasolar Planets
Encyclopaedia (also US
Mirror)
"The Formation of Planets - Theory" - Randall Cooper1. September 22, 2004Abstract:
Direct observational evidence in the past decade of the existence of
extrasolar planets has invigorated the curiosity of both astronomers
and laypersons about how planets are created. In my talk I will
explain some of the basic theory of planet formation. Planet
compositions constrain the possible formation processes, so I will
begin with a brief overview of the interiors of the Jovian planets. I
will then describe how a slowly rotating molecular cloud might
collapse to a star and a rotationally-supported disk. This disk is
the birthplace of planets, and I will discuss how some of the gas in
the disk forms into planetary embryos. I will conclude by explaining
some of the gas accumulation theories that may ultimately lead to a
fully-formed planet.
Reading material:
"The Architecture of Planetary
Systems" - Jonathan
Foster2. September 29, 2004Abstract:
Planetary systems all follow the same basic rules of gravity and
orbital dynamics. From a single sample system we guessed that planets
have circular orbits and that gas giants only exist far from a star.
The discovery of exoplanets in rather different configurations has
caused us to re-visit these assumptions. On the inner edge of the
solar system, hot (and very hot) Jupiters continue to challenge
theorists. The favored interpretation for these planets, migration,
leads naturally to a consideration of resonances, a phenomena common
in our own solar system which is being re-visited in greater depth to
explain the larger sample of known planets.
Reading material:
"Successful observational techniques" - Joel Hartman3. October 6, 2004Abstract:
After reviewing the basic schemes that astronomers use to observe
binary systems, and the information that can be obtained from each
method, I will discuss the different techniques that have been applied
successfully to the discovery of extrasolar planets. I will focus on
the pulsar timing method, the radial velocity method, the transit
method, and microlensing surveys. I will then compare the efficiency
of the different methods in finding planets of various masses and
semi-major axes.
Reading material:
"Physical properties of planets" - Kaloyan
Penev4. October 13, 2004Abstract:
In this talk I will discuss the properties of the extrasolar planets,
both observed and inferred from simulations and ideas about what their
internal structures look like. I will also discuss how these
properties evolve with time both for an isolated giant planet and for
a hot jupiter (i.e. effects of evaporation).Reading material:
"Future planet searches" - Heather Knutson5. October 20, 2004 (in Phillips)Abstract:
Recent discoveries have dramatically expanded our knowledge of
planetary systems, but they have also been limited in their ability to
detect low mass and/or long period planets around our nearest
neighbors. The next generation of planet searches will work to
overcome this limitation with a variety of new instruments, both on
the ground and in space. This talk will survey a range of new
missions, focusing on surveys which have only recently begun
observations, new instruments under construction, and future missions
which have been selected to receive funding.Reading material:
"Small body populations of the Solar System"
-Cesar Fuentes 6. October 27, 2004Abstract:
Meteorites and comets are well known for their role in astronomy's
history; however they are only a small fraction of the small body
population in the solar system. I will give a general overview of the
subdivision of these objects, the current understanding of their
properties and the impact that their study will bring to our knowledge
of the solar system's formation and evolution. Finally I will refer to
the different survey missions, specially the near-earth asteroid's
searches (those representing a threat to humanity).Reading material:
"Planetary Atmospheres" - Alexandre Tchekhovskoi7. November 3, 2004 Abstract:
The talk gives an introduction to the spectral properties of
Extrasolar Giant Planets atmospheres and the problem of atmospheric
evaporation. Techniques for atmospheric structure detection -- along
with examples of successful detections -- are presented, followed by
the discussion of novel approaches to the study of Close-in Extrasolar
Giant Planets atmospheres and related future observational projects.Reading material:
"Metallicity of Host Stars" - Cullen Blake8. November 10, 2004Abstract:
Following the discovery of the first extrasolar planets a search for
commonalities among the host stars indicated that these stars tend to
be richer in metals than "average" stars of similar spectral
types. Today, detailed information is available about abundances in
nearly all of the more than 100 stars known to host planets. I will
review the statistics of these measurements, the current theories of
the processes that might have resulted in the increased metallicities,
and the implications for planet search strategies.Reading material:
"Dynamical properties of planetary systems" - Matthew
McQuinn9. November 17, 2004Abstract:
In this talk I will present an eclectic set of interesting results and
theories about the dynamics of extrasolar planets. This will include
showing that planet-planet interactions are essential for modeling the
short-term orbital dynamics of the 2-planet system GJ876 and that the
probability of a secular resonance in the system Upsilon Andromedae is
very high (both results have interesting implications that extend
beyond the system in question). Also, I will describe a theory of
planetary migration caused by planetesimals and a theory that explains
the extremely large observed eccentricities through interactions
between very massive planets. And, if time permits, I will delve into
a few other interesting tidbits.Reading material:
"Disk-protoplanet interactions" - Heng Hao10. November 24, 2004Abstract:
I will give a brief review of the stellar system forming process. Some
surprising observations raise our interests in studying the
interaction of a protoplanet with a circumstellar gaseous disk that
results in migration of the protoplanet. I will explain the Type I and
Type II migration and their mechanisms, especially the gap formation.Reading material:
"Observations of Disks" - Xavier
Koenig11. December 1, 2004Abstract:
In the currently accepted picture of star formation, the development
of a disk of gas and dust that accretes material onto the star is
almost ubiquitous. In this talk I will present an introduction to the
ways that these circumstellar disks are observed around stars -
highlighting the different aspects that observations at different
wavelengths bring out, and the properties that disks have at different
evolutionary stages of a star's life. In relating this talk to star
and planet formation, I will discuss how the observed dissipation of
disks constrains our discussion and modelling of how planets form,
given the competing timescales that we find for both the former and
the latter. I will sum up by looking at the future prospects for ever
better observations of disks, with the advent of such facilities as
(among others) Spitzer and the SMA.Reading material:
Haisch, K. E. et al., 2001, ApJ, 553, L153
Habing, H. J. et al., 1999, Nature, 401, p456
Wilner, D. J. et al., 2002, ApJ, 569, L115
Protostars and Planets IV (book)
"Transiting planets" - Eliza Miller-Ricci12. December 8, 2004Abstract:
The discovery of the transit of the planet HD209458 b in 2000 (Brown
et al.) around a bright (V=7.65) star brought to fruition the idea
that an extrasolar planet could be detected not only by its radial
velocity signature, but also by the dimming of the observed light as
it passes in front of its host star. In the past year the number of
known transiting extrasolar planets has increased from 2 to 6,
including the recent discovery of a second planet transiting a fairly
bright star (TrES-1 orbiting a V=11.8 star). A number of follow-up
observations allow us to constrain the physical parameters of the
transiting planets. I will discuss several of the parameters that can
be studied through such observations including the determination of
planetary radii, atmosphere detection, and albedo and orbital
eccentricity from observations of the secondary eclipse. This part of
the talk will focus on constraining physical parameters for close-in
extrasolar giant planets as these are the only planets that have been
found to transit so far. I will also discuss the two recent papers
that explore the interesting prospect of detecting Earth-mass planets
through a measurement of transit timing.Reading material:
"Formation of terrestrial planets in
general extrasolar planetary systems" - Philip Nutzman
13. December 15, 2004Abstract:
Planets form from the swirling protoplanetary disk of dust and gas
surrounding young stars. I discuss the prevalent model of planet
formation, in which planets grow from planetesimal accretion. Aspects
of this process may lead to observational signatures of the formation
of rocky "terrestrial" planets like Earth in young star systems.Reading material:
"Pulsar planets" - Jaime Pineda14. December 15, 2004Abstract:
The detection of planets towards two Millisecond Pulsars (MSPs), PS
B1257+12 and M4, gives the opportunity to find Earth sized planets or
even, because of the detection is based on the very accurate timing
observations. It is by far the most accurate way to find extrasolar
planets. However, the presence of planets around MSPs has produced
much speculation about the origin. In this talk I will present a
summary of the evidence that has been collected and the techniques
used to support these detections. Also, I will describe different
theories for the formation of these objects.Reading material:
Questions or Comments? Send an
e-mail to kstanek@cfa.harvard.edu.