Seminars for Scientists

The Magnetospheric Multiscale (MMS) mission has had its first full year in orbit taking science data. After more than a decade of development, MMS has proven to be a superlative four-satellite space physics laboratory with the highest cadence and most accurate 3D plasma measurements ever made. In this talk, I review the MMS mission and its history, highlight the recent scientific advances, and talk about future efforts.

Modern spectropolarimetry has revealed that about 10% of massive, luminous, hot O, B and A-type stars harbor large-scale, organized (often predominantly dipolar) magnetic fields ranging in dipolar strength from a few hundred to tens of thousand Gauss. This talk will discuss the role of such fields in channeling and trapping the radiatively driven winds of massive stars.

The Miniature X-ray Solar Spectrometer (MinXSS) is a 3-Unit (3U) CubeSat to study the energy distribution of solar flare soft X-ray (SXR) emissions of the quiet Sun, active regions, and during flares and to model the solar SXR impact in Earth’s ionosphere, thermosphere, and mesosphere (ITM) using these MinXSS solar measurements. This presentation will include an overview of the MinXSS CubeSat design and first MinXSS results about the solar SXR spectra measurements and variability during June-August 2016.

TBD

ExoTerra is a Colorado small business founded by former Lockheed spacecraft engineers in 2011 and focused on innovative microsatellites for space exploration. Our Electrically Propelled Interplanetary CubeSat (EPIC) bus has a 6U and 12 U variant that enables CubeSat missions throughout the inner solar system – including the Moon, LaGrange points, Venus, Mars and NEAs. Our ESPA class Sol Rider is capable of missions as far out as Jupiter and its moons.

Planetesimals are the precursors to planets, and understanding their formation is an essential step towards developing a complete theory of planet formation. Traditional theories attempt to explain planetesimal formation from a “bottom-up” approach; small particles (e.g., dust grains) continually grow upward in mass and scale, finally reaching gravitationally bound objects. However, growing these particles beyond centimeter sizes is very difficult with traditional coagulation physics. In this talk, I will first describe the streaming instability and how it solves the centimeter growth problem. I will then present present a series of high resolution, first principles numerical simulations of protoplanetary disk gas and discuss the implications of these calculations for the formation of asteroids and Kuiper Belt Objects and for the construction of planetary systems.

Over the past two decades, the study of planets orbiting around other stars has emerged from relative obscurity to the forefront of modern astronomical and planetary sciences. In this seminar, we will discuss results from 3D climate models with relevance to the inner edge of the habitable zone, defined by runaway and moist greenhouse states, for Earth-like planets orbiting F-, G-, K-, and M-dwarf main sequence stars.

The Rosetta mission to comet 67P/Churyumov-Gerasimenko has expanded the field of cometary science from the realm of Earth-based astronomers to include that of planetary scientists and geologists. The unique capabilities of the mission in being able to provide some of the highest resolution images we have ever acquired from a space mission in addition to being the first to put a lander on the surface of a comet and escort the comet itself on its journey around the Sun for more than 2 years has given has given us unprecedented insights into cometary nuclei morphology and the unique processes that shape their landscapes. In this talk, I will try to give you an overview of the mission’s activities to date and highlight the surface morphology of comet 67P with its diverse, and at times truly bizarre as well as an update on our understanding of how these landscape form, and evolve, with time.

Since 2004, the Ultraviolet Imaging Spectrograph (UVIS) onboard the Cassini spacecraft has been observing the wide variety of satellites orbiting around Saturn. During this seminar, I will demonstrate how UVIS data can be used to retrieve photometric properties of the surface of satellites such as Mimas, Tethys or Dione and to analyze the weathering processes affecting those airless surfaces. I will also demonstrate how the UVIS data can be used to study the Titan airglow and help understand the interactions between Titan’s upper atmosphere, its environment and the Saturn’s magnetosphere.

After Mariner 10 obtained brief and tantalizing glimpses of the planet Mercury in its 1974-75 flybys, the will to know more was strong, but the costs of sending a spacecraft into orbit around the innermost planet discouraged any follow-up mission. However, through ingenious trajectory design, two affordable missions were eventually devised, with NASA selecting MESSENGER… Read more »

The MAVEN mission is focused on understanding the Mars upper atmosphere. It measures the solar input (via EUV, solar energetic particles, and the solar wind); the response related to composition, structure, and variability of the upper atmosphere, ionosphere, and magnetosphere; and the influence on the rate of escape of ions and neutrals to space and… Read more »

Globally, December 2015 through February 2016 contains the warmest winter surface skin and air temperatures in the AIRS observational record. Continuing this trend, the AIRS global surface temperatures of 2016 show the greatest positive anomalies from average during March and August, since AIRS observation begins in September 2002. This warming is particularly significant over the… Read more »

Airless bodies unlike our Earth are directly exposed to solar UV radiation and solar wind plasma. Their surfaces covered by fine-sized regolith dust will be charged and may be mobilized due to electrostatic forces. This electrostatic process has been first suggested five decades ago to explain the so-called ‘lunar horizon glow’, a bright cloud observed… Read more »

Without the shielding by a strong intrinsic magnetic field like Earth, the Martian atmosphere is exposed to the solar wind. The Mars-solar wind interaction accelerates and transports planetary ions away from Mars through a number of processes, including pick-up by the electromagnetic field in the solar wind. The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft… Read more »

For nearly a decade, the Cloud Imaging and Particle Size (CIPS) instrument onboard the NASA Aeronomy of Ice in the Mesosphere (AIM) satellite has observed various properties of polar mesospheric clouds (PMCs). PMCs, which are located near the summer polar mesopause, occur as a result of upwelling and cooling associated with the gravity-wave-driven global residual circulation, and are therefore sensitive to large-scale dynamics that influence the propagation and breaking of gravity waves in the summer mesosphere.
Here, I will discuss two cases in which large-scale variability led to anomalies in the occurrence frequency of PMCs.

The experimental goal of the Orbiting Carbon Observatory (OCO-2) is to measure CO2 on regional scales to 1 ppmv accuracy in order for the Carbon Cycle modeling community to obtain better understanding of the natural land and ocean sources and sinks of CO2. These measurements are difficult due to the fact that atmospheric CO2 is…