Calendar

Aug
17
Fri
No Colloquium
Aug 17 @ 3:15 pm – 4:15 pm
No Colloquium @ BX102

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Colloquium Speaker Name, Affiliation

Abstract text

Aug
24
Fri
Colloquium: Dawn Gelino (Host: Tom Harrison)
Aug 24 @ 3:15 pm – 4:15 pm
Colloquium: Dawn Gelino (Host: Tom Harrison) @ BX102

NASA, Exoplanets, and Life After NMSU

Dawn Gelino, NASA Exoplanet Science Institute, CalTech

Abstract:  Are you interested in learning more about the search for life in the Universe? Or perhaps you may be interested in being awarded time on 10 m telescopes for your science? Or maybe you are ready to learn more about prestigious NASA Postdoctoral Fellowships? This talk will touch on some recent and exciting results in the exoplanet field, as well as the different NASA HQ programs that I currently run for all of astrophysics (many of which may be helpful and applicable to YOU), and the path I took from NMSU to where I am now.

Aug
31
Fri
Colloquium: Don Terndrup (Host: Nancy Chanover)
Aug 31 @ 3:15 pm – 4:15 pm
Colloquium: Don Terndrup (Host: Nancy Chanover) @ BX102

Stellar Winds and Stellar Rotation

Don Terndrup, Ohio State University

For more than 50 years, we have known that stars rotate quickly when they are young and slow down as they age.  This process gives us important clues about magnetic field strength and geometry, as well as the nature of stellar winds, in solar-like stars.  We have been working to put the analysis of stellar rotation on a modern statistical footing, and in this talk I will give you an update on our efforts.  There are a number of critical observational problems that must be considered in calibrating models of angular momentum loss, especially problems of data censorship (older or less active stars are not detected in studies of rotation).  I will conclude by evaluating the prospects for using stellar rotation as an age indicator, and demonstrate that such ages are far less precise – though still useful – than our group and others have previously claimed.

 

 

Sep
7
Fri
No Colloquium
Sep 7 @ 3:15 pm – 4:15 pm
No Colloquium @ BX102

Colloquium Title

Colloquium Speaker Name, Affiliation

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Sep
12
Wed
Colloquium PhD Thesis Defense: Alexander Thelen (Host: Nancy Chanover)
Sep 12 @ 3:00 pm – 4:00 pm
Colloquium PhD Thesis Defense: Alexander Thelen (Host: Nancy Chanover) @ Domenici Hall Room 102

The Chemical Composition and Dynamics of Titan’s Atmosphere as Revealed by ALMA

Alexander Thelen, NMSU

Over the last century, remarkable advances in our understanding of Titan’s atmosphere have been accomplished by a campaign of ground- and space-based observations revealing a wealth of complex, organic species in the moon’s upper atmosphere. Many of Titan’s atmospheric constituents produced through the photochemistry and ionospheric interactions of N2 and CH4 exhibit significant variations with latitude and time, particularly towards the poles and within the winter circumpolar vortex. The measurement of spatial and temporal variations in Titan’s atmosphere enables us to elucidate connections between its dynamics, photochemistry, and the influence of seasonal changes. At the end of the Cassini mission in 2017, we can employ the Atacama Large Millimeter/submillimeter Array (ALMA) for future observations of Titan’s atmosphere. Here we detail the analysis of numerous short integration (~3 minute) ALMA observations from 2012 to 2015 to investigate Titan’s stratospheric composition, temporal variations, and search for new molecular species. Using the Non-linear optimal Estimator for MultivariatE spectral analySIS (NEMESIS) radiative transfer code, we retrieved vertical profiles of temperature and abundance in Titan’s lower stratosphere through mesosphere (~50–550 km) from three spatially independent regions. We modeled CO emission lines to obtain temperature measurements, and retrieved abundance profiles for HCN, HC3N, C3H4, and CH3CN. The combination of integrated flux maps and vertical atmospheric profiles from spatially resolved observations allowed us to study the circulation of Titan’s middle atmosphere during northern spring. We observed increased temperatures in Titan’s stratopause at high northern latitudes and a persistent northern enrichment of HCN, C3H4, and CH3CN during this epoch; however, increased abundances of all molecules in the southern mesosphere, particularly HCN, and spatial maps of HC3N also show evidence for subsidence at the south pole. We validated these measurements through direct comparisons with contemporaneous Cassini data, previous ground-based observations, and photochemical model results. While no new trace species were detected, ALMA has proven to be a highly capable asset to enhance the data from the final few years of the Cassini mission, and for the continued study of Titan’s atmospheric dynamics, composition, and chemistry into Titan’s northern summer.

Sep
14
Fri
No Colloquium
Sep 14 @ 3:15 pm – 4:15 pm
No Colloquium @ BX102

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Colloquium Speaker Name, Affiliation

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Observatory Open House
Sep 14 @ 8:00 pm – 9:00 pm
Observatory Open House @ Tombaugh Observatory

Host: Chris Churchill. Assisted by Trevor Picard, Lauren Kahre, and Ali Hyder

Sep
21
Fri
Colloquium: Dave Thilker (Host: Rene Walterbos)
Sep 21 @ 3:15 pm – 4:15 pm
Colloquium: Dave Thilker (Host: Rene Walterbos) @ BX102

Colloquium Title

Colloquium Speaker Name, Affiliation

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Sep
24
Mon
Pizza lunch: Drew Chojnowski
Sep 24 @ 12:30 pm – 1:30 pm
Pizza lunch: Drew Chojnowski @ AY 119

Ap Stars

Sep
28
Fri
Colloquium: Bharat Ratra (Host: Anatoly Klypin)
Sep 28 @ 3:15 pm – 4:15 pm
Colloquium: Bharat Ratra (Host: Anatoly Klypin) @ BX102

Dark Energy

Bharat Ratra (KSU)

Abstract text