Diagnosing the SEEDS of Planet Formation
John Wisniewski, University of Oklahoma
Circumstellar disks provide a useful astrophysical diagnostic of the formation and early evolution of exoplanets. It is commonly believed that young protoplanetary disks serve as the birthplace of planets, while older debris disks can provide insight into the architecture of exoplanetary systems. In this talk, I will discuss how one can use high contrast imaging techniques to spatially resolve nearby circumstellar disk systems, and how this imagery can be used to search for evidence of recently formed planetary bodies. I will focus on results from the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) project, as well as some ongoing follow-up work.
Magnetic Influences on Coronal Heating and the Solar Wind
Lauren Woolsey, Harvard University
The physical mechanism(s) that generate and accelerate the solar wind have not been conclusively determined after decades of study, though not for lack of possibilities. The long list of proposed processes can be grouped into two main paradigms: 1) models that require the rearranging of magnetic topology through magnetic reconnection in order to release energy and accelerate the wind and 2) models that require the launching of magnetoacoustic and Alfvén waves to propagate along the magnetic field and generate turbulence to heat the corona and accelerate the emanating wind. After a short overview of these paradigms, I will present my ongoing dissertation work that seeks to investigate the latter category of theoretical models and the role that different magnetic field profiles play in the resulting solar wind properties with Alfvén-wave-driven turbulent heating. I will describe the computer modeling in 1D and 3D that I have done of bundles of magnetic field (flux tubes) that are open to the heliosphere, and what our results can tell us about the influences of magnetic field on the solar wind in these flux tubes, including the latest time-dependent modeling that produces bursty, nanoflare-like heating. Additionally, I will present the latest results of our study of chromospheric network jets and the magnetic thresholds we are finding in magnetogram data.
The NMSU Department of Astronomy will hold an observatory open house at the NMSU campus observatory at 8 p.m.Friday, Sept. 9. Astronomy personnel on hand will be Chris Churchill and graduate assistants Xander Thelen, Trevor Picard and Jacob Vander Vliet.
Guests can view Mars and Saturn together in the evening sky in the constellation of Scorpio. Telescopes will also have the center of the Milky Way Galaxy in view, and in this region there are many beautiful star clusters and globular clusters (tight groups of millions of stars). High in the sky, viewers will see the constellation Vega with its double-double star system and the famous ring nebula, which is the remnants of a dying star much like our own sun. The moon will be in the phase called first quarter and will make a wonderful sight.
Contact the NMSU Astronomy Department at 575-646-4438 with questions. Everyone is welcome to come and spend an evening of stargazing. Admission is free and children are especially welcome to attend.
For information on what is up in September, go here: http://whatsouttonight.com/Resources/2016SepSkyWOT.pdf