Category: Seminars

February 16 seminar: First Results from Juno Mission

February 14th, 2017 in Seminars

First Results of the Juno Mission in Jupiter’s Magnetosphere


Jack Connerney
NASA GSFC

Thursday, February 17, 2017
Refreshments: 3:45 pm, CAS 500
Seminar: 4:00 pm, CAS 502:

Abstract:

The Juno spacecraft entered polar orbit about Jupiter on July 4, 2016, after a Jupiter Orbit Insertion (JOI) main engine burn lasting 35 minutes. Juno’s science instruments were not powered during the critical maneuver sequence (~5 days) but were fully operational shortly thereafter. Juno’s current 53.5 day polar orbit spans the Jovian magnetosphere from bow shock (>100 Rj) to the planet (periapsis at 1.06 Rj) and back, providing magnetic field, charged particle, and wave phenomena context for the passage over the poles and first traverse of Jupiter’s hazardous inner radiation belts. Juno’s energetic particle and plasma detectors made the first measurements of electrons precipitating in the polar regions, exciting intense ultraviolet (UV) and infrared (IR) auroras, also observed simultaneously by Juno’s UV and IR imaging spectrographs. Juno transited beneath the most intense parts of the radiation belts, passed a few thousand kilometers above the cloudtops at closest approach, and recorded the electrical signatures of high velocity impacts with small particles as it traversed the Jovigraphic equator. The first few periapsis passes revealed an extraordinary spatial variation of the magnetic field close to the planet’s surface, suggesting that Juno may be sampling the field closer to the dynamo region than widely anticipated, i.e., portending a dynamo surface extending to relatively large radial distance (~0.9Rj?). Global mapping of the gravity and magnetic fields will continue until some 32 periapsis passes are acquired, evenly spaced in longitude about the planet, wrapping Jupiter in a dense net of observations ideally suited to characterizing the magnetic field. When finished, Juno will have painted the most detailed image of the field at a dynamo surface – with more resolution than one can achieve in orbit about Earth.

January 30 seminar: Plasma Physics and Kinematics of the Intracluster Medium, ZuHone, CfA

January 26th, 2017 in Seminars

Probing the Plasma Physics and Kinematics of the Intracluster Medium with X-ray Observations and Simulations

John ZuHone
CfA

Monday, January 30, 2017
3:15 pm – Refreshments, CAS 300
3:30 pm – Seminar, CAS 502

Abstract:
Since its launch in 1999, the Chandra X-ray Observatory has provided unprecedented views of the hot plasma of galaxy clusters, revealing structures such as shocks, cold fronts, and indications of gas turbulence. Before its unfortunate demise, the Hitomi mission provided the first direct measurements of gas motions in the Perseus cluster. All of these observations indicate the intracluster medium (ICM) has interesting plasma properties and is continuously stirred by gas motions large and small driven by mergers and AGN feedback. In this talk, I will present the results of a number of hydrodynamical simulations of galaxy cluster mergers and compare them to observations with a view towards constraining the plasma and kinematic properties of the ICM. I will finish my talk with a view toward future X-ray missions and what may be revealed in the cluster plasma by the combination of high spectral and spatial resolution.

January 26 seminar: The Risks of Multiple Breadbasket Failure, Anthony Janetos, BU

January 26th, 2017 in Seminars

The Risks of Multiple Breadbasket Failure

Anthony Janetos
BU

Thursday, January 26, 2017
3:45 pm – Refreshments, CAS 300
4:00 pm – Seminar, CAS 502

Abstract:
We are headed into a world where the risks from climate change of failure of agricultural productivity in the world’s major breadbaskets cannot be ignored. I discuss both a modeling study to illustrate how those risks may occur, and their consequences, and a broader research strategy of modeling and observation that can provide practical examples for moving forward in a rapidly changing world.

Monday December 12, 2016 Seminar: Breaking Through the Exoplanetary Atmospheres

December 6th, 2016 in Seminars

Breaking Through Exoplanetary Atmospheres

Mercedes Lopez-Morales
CfA

Monday, December 12, 2016
3:00 pm – Refreshments, CAS 300
3:45 pm – Seminar, CAS 502

Abstract:

In the past two decades we have gone from only knowing about the planets in our own Solar System to discovering thousands of planets orbiting around other stars. We have not only discovered that planets abound, but also that most planetary systems do not resemble our own. One of the next steps in the field of exoplanets is to study their atmosphere and answer questions such as: do the physical properties of gas giant exoplanets resemble those of the Solar System giants? Are there exoplanets with atmospheres similar to Earth? In this talk I will describe the state of the art techniques we are using and developing to characterize exoplanetary atmospheres, the main results so far, and our plan for the future.

Monday December 5, 2016 Seminar: The Role of Magnetic Fields in Star Formation – Zeeman Effect Observations and other Observables

December 1st, 2016 in Seminars

The Role of Magnetic Fields in Star Formation – Zeeman Effect Observations and other Observables

Tom Troland
University of Kentucky

Monday, December 5, 2016
3:00 pm – Refreshments, CAS 500
3:45 pm – Seminar, CAS 502

Abstract:

TBA

Thursday November 17, 2016 Seminar: Rolling the BARREL the wrong way: Using Radiation Belt missions to study Solar Phenomena

November 15th, 2016 in Seminars


Rolling the BARREL the wrong way: Using Radiation Belt missions to study Solar Phenomena

Sarah McGregor
Keene State College

Thursday, November 17, 2016
3:45 pm – Refreshments, CAS 500
4:00 pm – Seminar, CAS 502

Abstract:

BARREL (Balloon Array for Radiation belt Relativistic Electron Losses) is an array of balloons launched by Dartmouth to study the Earth’s Radiation Belts. Intended to look at atmospheric losses of precipitating electrons, BARREL flew an array of balloons in Antarctica during the winter of 2014. But Radiation Belt electrons aren’t the only source of high energy particles that BARREL could potentially observe. Floating at higher latitudes it is possible for BARREL to observe Solar Energetic Particles as they penetrate into the Earth’s magnetosphere. The signature of these particles would be different than those of the Radiation Belts, and would be ‘noise’ to those looking for Radiation Belt Losses. In order to investigate Radiation Belt Losses BARREL measures high energy X -rays emitted from the precipitating particles as they enter the atmosphere. But these precipitating particles aren’t the only source of hard X-rays. The Sun, in the form of Solar Flares, does as well. Although predominantly characterized by their soft X-rays as observed by the GOES spacecraft, Solar Flares emit hard X-rays as energized particles plummet into the chromosphere. In this talk I will update you on some of our efforts to use the unintentional solar noise in BARRELs data, both from Solar Energetic Particles and Flares, to investigate solar dynamics and motivate undergraduates students to do Space Physics Research.

Monday November 14, 2016 Seminar: Gravitational Wave Detection with Advanced LIGO

November 8th, 2016 in Seminars

Gravitational Wave Detection with Advanced LIGO

Matthew Evans
MIT

Monday, November 14, 2016
3:15 pm – Refreshments, CAS 500
3:30 pm – Seminar, CAS 502

Abstract:

The Laser Interferometer Gravitational-wave Observatory (LIGO)recently made the first direct detection of gravitational waves; minute distortions in space-time caused by cataclysmic events far away in the universe. I will talk about the sources of the signals we detected, the physics behind the detectors, and prospects for the future of this emerging field.

Thursday November 10, 2016 Seminar: Update from the MMS Mission

November 8th, 2016 in Seminars


Agyrotropy in the Electron Diffusion Region of Asymmetric Magnetic Reconnection

Matthew Argall
UNH

Thursday, November 10, 2016
3:00 pm – Seminar, CAS 500

Abstract:

The Magnetospheric Multiscale (MMS) mission was launched on March 13, 2015 and consists of four spacecraft in a tetrahedral configuration. Its mission is to unravel the mystery of particle acceleration in collisionless plasmas during magnetic reconnection. It has set a world record for use of GPS at the highest altitude of any space mission — a feat that has allowed it to maintain a mean seperation 7km or 2-3 electron skin depths at magnetopause. This formation has allowed MMS to spatially resolve electron-scale structures. Furthermore, the unprecedented time-resolution of the fields and particles suites has made it possible to study many of the rapidly changing processes of reconnection. Once such process is plasma mixing and acceleration in the electron diffusion region (EDR), which leads to agyrotropic electron distribution functions. In this seminar, I will present an overview of MMS, some of its recent discoveries, and the insight the Electron Driff Instrument (EDI) is providing in our study of the EDR.

Monday November 7, 2016 Seminar: Supernovae and their Progenitor Systems

November 8th, 2016 in Seminars

Supernovae and their Progenitor Systems (or lack thereof)

Ori Fox
STScl

Monday, November 7, 2016
3:15 pm – Refreshments, CAS 500
3:30 pm – Seminar, CAS 502

Abstract:

Despite the robust empirical supernova (SN) classification scheme in place, the underlying progenitor systems remain ambiguous for many subclasses. The most straightforward constraint relies on a detection of the progenitor star in high-resolution pre-explosion images. Such a direct identification is typically not feasible, however, even with modern telescopes such as Hubble. Instead, astronomers are forced to rely on supernova “forensics,” where the surrounding circumstellar medium can yield direct clues about the mass loss from the star in the years leading up to the SN explosion.
I will begin the talk with a review of the limited number of direct progenitor detections already made, followed by a discussion of the indirect methods for constraining supernova progenitors that have never been seen. Although pro- genitor discussions have historically considered mostly single star systems, I will focus a significant portion of the discussion on the impact binary stars may have on our understanding of these results.

Thursday November 3, 2016 Seminar: Human-in-the-Loop Coordination with Robot Systems

October 27th, 2016 in Seminars

Human-in-the-Loop Coordination with Robot Systems

Holly Yanco
U Mass Lowell

Thursday, November 3, 2016
3:00 pm – Refreshments, CAS 500
3:45 pm – Seminar, CAS 502

Abstract:

Robots navigating in difficult and dynamic environments often need assistance from human operators or supervisors, either in the form of teleoperation or interventions when the robot’s autonomy can not handle the current situation. Even in more controlled environments, such as office buildings and manufacturing floors, robots may need help from people. This talk will discuss the best practices for controlling both individual robots and groups of robots, in applications ranging from assistive technology to telepresence to search and rescue. A number of methods for human-in-the-loop coordination with robot systems, including multi-touch devices, software-based operator control units (softOCUs), game controllers, Oculus Rift, and Google Glass, will be presented.
Bio: Dr. Holly Yanco is a Distinguished University Professor, Professor of Computer Science, and Director of the New England Robotics Validation and Experimentation (NERVE) Center at the University of Massachusetts Lowell. Her research interests include human-robot interaction, multi-touch computing, interface design, robot autonomy, fostering trust of autonomous systems, evaluation methods for human-robot interaction, and the use of robots in K-12 education to broaden participation in computer science. Yanco’s research has been funded by NSF, including a CAREER Award, ARO, DARPA, DOE-EM, NASA, NIST, Microsoft, and Google. Yanco was the General Chair of the 2012 ACM/IEEE International Conference on Human-Robot Interaction and served as Co-Chair of the Steering Committee for the HRI Conference and Journal from 2013-2016. Yanco has a PhD in Computer Science from the Massachusetts Institute of Technology.