Calendar

Apr
6
Fri
Colloquium PhD Thesis Defense: Sten Hasselquist
Apr 6 @ 3:15 pm – 4:15 pm
Colloquium PhD Thesis Defense: Sten Hasselquist @ BX102

Colloquium Title

Sten Hasselquist, NMSU

Abstract

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.

Jan
20
Sun
Lunar Eclipse – Public Outreach Event
Jan 20 @ 7:45 pm – 10:30 pm
Lunar Eclipse - Public Outreach Event

The NMSU Astronomy Department will be holding a two-part public event for the January 20th total lunar eclipse!

Starting at 7:45 PM, Professor Kristian Finlator will give a talk on the eclipse in the Biology Annex (located here) from 7:45 PM to 8:15 PM, with a second provisional talk planned at 8:30 PM in case attendance is too high for everyone to fit into the room for the first talk.

From 8:30 pm to 10:30 PM the telescopes at Tombaugh Observatory (located here, a short walk/drive from the Biology Annex) will be opened and graduate students will be on hand to answer questions and run the telescopes. Feel free to come to one or both of these events, or to arrive to the telescopes at any time between 8:30 and 10:30. Please keep in mind, the eclipse begins around 8:30, but totality (or, when the moon turns red from fully entering Earth’s shadow) doesn’t begin until ~9:40 PM. The Society of Astronomy Students will also be on site with hot chocolate!

Parking is available at both locations. If there is a possibility of inclement weather, please call the Observatory Hotline (575-646-6278) to make sure that we will have the telescopes open (if there’s a chance of rain, we will not open the telescopes, and we will leave a message at this number saying so).

Mar
5
Tue
Public Talk: Janna Levin: Black Hole Blues
Mar 5 @ 7:30 pm – 8:45 pm
Mar
19
Tue
Colloquium: Jack Burns
Mar 19 @ 7:30 pm – 8:30 pm
Colloquium: Jack Burns @ Domenici Hall 109

Our Future in Space: The Moon and Beyond

Jack Burns, University of Colorado Boulder

Why do we explore space? How do we explore
space? Where should we explore? What are
the tools for space exploration? These questions will be addressed in this talk focused on
the future of human and robotic exploration of
the solar system and beyond. Since the end of
the Apollo program, the justification for the human space program has proven elusive. We will
borrow a page from the computer and new
commercial space companies to argue for an
inspirational approach to the next phase of
exploration beyond Earth orbit. The “how” is
addressed with NASA’s new Orion and Space
Launch Systems along with new launch systems being developed by private companies
such as SpaceX and Blue Origin. We will argue
that both the Moon and Mars can be explored
through a combination of governmental programs, international partnerships, and public-
private partnerships. The tools for exploration
include telerobotics where astronauts aboard
NASA’s Lunar Gateway in orbit of the Moon
will operate rovers and deploy telescopes on
the lunar surface in a new synergy between
robots and humans.