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Revealing Fomalhaut b's True Nature

Assistant Astronomer Andras Gaspar and Professor George Rieke propose a solution to the decade old mystery of the first directly imaged exoplanet, Fomalhaut b, in an article recently published in the Publications of the National Academy of Sciences. First discovered in 2008 in images taken with the Hubble Space Telescope (HST) in 2004 and 2006, Fomalhaut b has always been an enigmatic object within the group of roughly two dozen directly imaged exoplanets. Despite being observed multiple times in the optical, it remains undetected at infrared wavelengths, contrary to expectations for a massive planet. In addition, its eccentric orbit crosses the debris ring around the star, yet the ring does not show the perturbations expected from interaction with a massive planet. 

While designing upcoming observations of the Fomalhaut debris disk system using their group's Guaranteed Observing Time on the James Webb Space Telescope, Gaspar methodically reduced all archival HST observations on the system, including unpublished 2013 and 2014 data. To his surprise, the Fomalhaut b object was not detected in the 2014 dataset, leading to their in-depth analysis and theoretical modeling of the Fomalhaut b object. 
Additionally, they found that the object has been fading since its first observation and that its size (spatially resolved in the later datasets) has been increasing. Finally, its orbit was now better explained by an escaping trajectory. These observational aspects all pointed towards a single plausible explanation: the object is a large expanding dust cloud on a radially escaping path. Such a cloud would be produced by a massive collision between two large asteroidal objects.
Dr. Gaspar gave us three photos: HERE is a video of the system over time. 
HERE is the cover photo. And HERE is an artist's conception of creating the dust cloud. 


Aaronson Symposium On Galactic Dynamics With Resolved Stars, postponed to Spring 2022

The first Marc Aaronson science symposium will be held here at the University of Arizona. Because of COVID-19 it has been postponed until Spring 2022.  The conference will be organized around 3 key topics:1)  The secular evolution of galaxies: Physical insights (to be) learned from 6D phase space information of the major baryonic components (bulge, bar and disk) of Local Group galaxies.; 2) The distribution of dark matter in galaxies: Physical insights (to be) learned from 6D phase space of tracers of the dark matter halo of Local Group galaxies (globular clusters, satellites, streams and stars); 3) The nature of dark matter: Physical insights (to be) learned from 6-D phase space information of dark matter dominated systems and systems affected by dark matter.

The Scientific Organizing Committee is: Gurtina Besla (Chair), Dennis Zaritsky (chair), Vasily Belokurov, Kathryn Johnston, Nitya Kallivayalil, Knut Olsen, Hans-Walter Rix, Louis Strigari.

You can learn more HERE and HERE. You can submit an Abstract HERE.

Note that there have been 19 Aaronson Prize Lectures from 1989 to the present, and an Aaronson@30 Symposium in 2017. Our intention is to alternate Aaronson Science Symposia and Aaronson Prize Lectures.

You can learn more about Marc Aaronson HERE

Science News/Links at Steward

Three very recent science articles by/about Steward people. If you have one, send it to edo.

1) ASTROBITES: Samantha Scibelli & Yancy Shirley, "COMs in Cores: Complex Chemistry in Dense Cores in the Taurus Star-Forming Region". LINK HERE.

2) Chris Impey, "the Conversation." "Coronavirus: Social distancing is delaying vital scientific research." LINK HERE.

3) Chris Impey, "the Conversation," How technology can combat the rising tide of fake science." LINK HERE.

The photo is from Adam Block. You can see it and others HERE.

Jinyi Yang Will Be Our Second Strittmatter Fellow

We are pleased to announce that Dr Jinyi Yang, who has been a Postdoctoral Research Associate at Steward since late 2017, is going to become  (Fall 2020) Steward's second Peter A. Strittmatter Fellow, succeeding Dr. Taran Esplin. You can read about the fellowship HERE

Jinyi has kindly provided a brief synopsis of her current scientific projects:

"My main interests include the study of reionization-era quasars, of the history of reionization, and of early super-massive black holes (SMBHs).  I am currently working on a wide-field survey for quasars with redshifts beyond seven, which has yielded the discovery of a new redshift record breaking quasar, and performing the multi-wavelength follow up observations of these distant systems, from X-ray to radio wavelengths. As a Strittmatter Fellow, I will focus on the investigations of the reionization history at the redshift range z~6-7.5 and the SMBHs growth using our newly constructed z>~7 quasar sample, the first large statistical significant quasar sample in the reionization epoch. In addition, I will use ALMA high resolution imaging to directly measure the BH masses of the ultra luminous individuals and study the BH-host interaction in the central region surrounding the maximally accreting black hole. My on-going/future HST and JWST projects will also allow me to give deep insights into the early SMBHs and their host galaxies."    

UArizona COVID-19 Information

Since we now have the big featured article on we thought it would be nice to put up some links to other things here. Because of staffing issues we aren't changing the title of this page.

1)Samantha Scibelli & Yancy Shirley's paper  on Astrobites : "COMs in Cores: Complex Chemistry in Dense Cores in the Taurus Star-Forming Region"

2) Two Chris Impey papers on "The Conversation" HERE and HERE. Titles are "Coronavirus: Social distancing is delaying vital scientific research," and "How technology can combat the rising tide of fake science"

SheTech Event Features High School Student Working With Steward Staff

Ellie Wolcott is a junior in the Engineering Program at Andrada High School  from the Vail School District. She is featured at today’s SheTech Explorer Day at the Steward Observatory booth showing her telescope model. A blow-up of the photo is HERE. Ellie Wolcott, Kelly Merrill, and Kerry Gonzales are left to right.

In her internship, she has learned the SolidWorks design program and created a 3-D model of a 2 meter telescope. The scaled model of her design was 3-D printed and was featured at the Steward Observatory booth as shown below. She is one of the four students in the Steward Observatory High School Internship Program which is collaborating with the Vail School District.

Derek Langley is the Engineering instructor at Andrada High School who has helped to facilitate this and other dynamic experiences for his students and program. The Steward Observatory Staff supporting this effort is Kerry Gonzales, Mario Rascon, Kelly Merrill and Jeff Kingsley.

The City of Tucson Office of Economic Initiatives in partnership with UA Tech Parks Arizona is pleased to launch Arizona’s first SheTech Explorer Day! This day‐long, industry‐led STEM exploration event provides hands‐on, interactive activities in science, technology, engineering and math (STEM) for rising 9th through 12th grade girls.



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