Seminars for Scientists

NASA’s Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) spacecraft is now well into its primary mission to initiate a new era in our understanding of the innermost planet. MESSENGER became the first spacecraft to orbit Mercury on 18 March 2011. MESSENGER’s Mercury Dual Imaging System is acquiring a global monochrome image mosaic at better… Read more »

Polypyrrole is an air-stable organic conducting polymer. It can be easily prepared in the form of microscopic particles or alternatively deposited as an ultrathin overlayer on either polymer latex particles or mineral grains. Its conductivity is sufficiently high to enable the efficient accumulation of surface charge and hence acceleration of such colloidal particles up to… Read more »

The Interstellar Boundary Explorer (IBEX) mission has been remotely observing the global interaction of our heliosphere with the local interstellar medium for over two and a half years. Initially, IBEX generated the first all-sky maps of Energetic Neutral Atoms (ENAs) emanating in from the boundaries of our heliosphere over the energy range from ~0.1-6 keV…. Read more »

Saturn’s ice moon Enceladus turned out to be one of the most intriguing bodies in the solar system. Data returned by several instruments on the Cassini spacecraft provide compelling evidence that this moon is unusually active and is capable of maintaining a pronounced ice volcanism. In particular, measurements of the spatial distribution of the plume… Read more »

Imagine what it would be like to observe a “protoplanetary” disk at a resolution of one kilometer over a time span of a 1000 orbits. The Cassini spacecraft has been observing the Saturn system at close range for the past 7 years. During this time, Saturn’s rings have been found to be more complex and… Read more »

Earth provides a testbed for fine tuning crewed and robotic mission concepts prior to their launch. I have been participating in several NASA-funded projects that assess the scientific return from various mission scenarios. For example, last month we assessed the potential for quality science data for a proposed crewed landing on an asteroid. In this… Read more »

Uncertainties in the solar irradiance could have a large impact on simulations of the climate system, since the response of the atmosphere strongly depends on the spectral distribution of the solar irradiance. Most (chemistry) climate models today use the standard NRLSSI (Lean) spectral variability to study the effect of the 11-year solar cycle on climate…. Read more »

How well do we know how much energy is coming in to the Earth’s climate system? And — although a much more difficult measurement — how much of that is lost to space?Climate-quality data require more stringent measurement accuracies and stabilities than needed for shorter-term studies. LASP is helping improve the measurements of both the… Read more »

In collisionless space plasmas, the Hall physics plays a significant role in magnetic reconnection. In this talk, I will show the evidence for the Hall electromagnetic field for a reconnection event seen by Cluster in the magnetotail. And I will talk about the newly developed reconstruction method, which is used to produce 2-D maps of… Read more »

There is abundant evidence that the ancient Martian climate was different from the present one. Liquid water was present, leaving behind both geological and geochemical evidence. But the present climate is cold and dry, unable to support sustained liquid water at the surface. I’ll discuss the evidence for climate change and the processes that might… Read more »

The Thermal Emission Imaging System (THEMIS) on the 2001 Mars Odyssey Spacecraft has provided thermal infrared (IR) spectra of materials dispersed throughout the low albedo Noachian and Hesperian-aged southern highlands plains units that show a featureless slope towards longer wavelengths. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) visible/near infrared spectral observations for the sites indicate… Read more »

NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft is now well into its primary mission to initiate a new era in our understanding of the innermost planet. MESSENGER became the first spacecraft to orbit Mercury on 18 March 2011. MESSENGER’s Mercury Dual Imaging System is acquiring a global monochrome image mosaic at better… Read more »

Polypyrrole is an air-stable organic conducting polymer. It can be easily prepared in the form of microscopic particles or alternatively deposited as an ultrathin overlayer on either polymer latex particles or mineral grains. Its conductivity is sufficiently high to enable the efficient accumulation of surface charge and hence acceleration of such colloidal particles up to… Read more »

The Interstellar Boundary Explorer (IBEX) mission has been remotely observing the global interaction of our heliosphere with the local interstellar medium for over two and a half years. Initially, IBEX generated the first all-sky maps of Energetic Neutral Atoms (ENAs) emanating in from the boundaries of our heliosphere over the energy range from ~0.1-6 keV…. Read more »

Saturn’s ice moon Enceladus turned out to be one of the most intriguing bodies in the solar system. Data returned by several instruments on the Cassini spacecraft provide compelling evidence that this moon is unusually active and is capable of maintaining a pronounced ice volcanism. In particular, measurements of the spatial distribution of the plume… Read more »

Earth provides a testbed for fine tuning crewed and robotic mission concepts prior to their launch. I have been participating in several NASA-funded projects that assess the scientific return from various mission scenarios. For example, last month we assessed the potential for quality science data for a proposed crewed landing on an asteroid. In this… Read more »

Uncertainties in the solar irradiance could have a large impact on simulations of the climate system, since the response of the atmosphere strongly depends on the spectral distribution of the solar irradiance. Most (chemistry) climate models today use the standard NRLSSI (Lean) spectral variability to study the effect of the 11-year solar cycle on climate…. Read more »

How well do we know how much energy is coming in to the Earth’s climate system? And — although a much more difficult measurement — how much of that is lost to space? Climate-quality data require more stringent measurement accuracies and stabilities than needed for shorter-term studies. LASP is helping improve the measurements of both… Read more »

In collisionless space plasmas, the Hall physics plays a significant role in magnetic reconnection. In this talk, I will show the evidence for the Hall electromagnetic field for a reconnection event seen by Cluster in the magnetotail. And I will talk about the newly developed reconstruction method, which is used to produce 2-D maps of… Read more »

There is abundant evidence that the ancient Martian climate was different from the present one. Liquid water was present, leaving behind both geological and geochemical evidence. But the present climate is cold and dry, unable to support sustained liquid water at the surface. I’ll discuss the evidence for climate change and the processes that might… Read more »

The Thermal Emission Imaging System (THEMIS) on the 2001 Mars Odyssey Spacecraft has provided thermal infrared (IR) spectra of materials dispersed throughout the low albedo Noachian and Hesperian-aged southern highlands plains units that show a featureless slope towards longer wavelengths. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) visible/near infrared spectral observations for the sites indicate… Read more »