Events

May 8, 2024 11:00 - 12:00 EDT

Cool Joules: Remote Sensing of the Ice Giants in the Thermal Infrared

Webinar Zoom Link

Presenter: Dr. Conor Nixon (NASA Goddard)
Abstract: The Voyager 2 flybys of Uranus (1986) and Neptune (1989) have given us the only close-up views of the two ice giant planets to date. Carrying a diverse "toolbox" of instruments, Voyager 2 vastly increased our knowledge of these worlds and their systems, including the discovery of new rings and moons, measurement of the rotation periods and plasma environments, imaging of clouds and more. One instrument onboard Voyager 2 was the InfraRed Interferometer Spectrometer (IRIS), which made spectroscopic measurements across the thermal infrared from 5 to 50 microns (2000 to 200 cm-1). Despite providing a wealth of data on the Jovian and Saturnian systems, IRIS was not sensitive enough to survey the spectra of the cold ice giants (T_eff ~ 59 K) across much of the mid-IR, eventually achieving a S/N > 1 only between 20-30 microns (200-320 cm-1). Since then, important new thermal IR spectroscopic measurements have been made with space telescopes such as ISO, Herschel, Spitzer and JWST. However, from vantage points near the Earth, these observatories are lacking in the spatial resolution needed to provide detailed atmospheric mapping, and blind to the atmospheric activities at the winter pole. Devising a new mid-IR spectrometer for a future Uranus or Neptune mission that can significantly improve on IRIS is challenging, requiring very sensitive detectors that likely require active cooling. This in turn generates challenges for instrument size, weight and power (SWaP) on missions whose instrument complements are perpetually asked to "do more with less." In this talk I will review the potential science return for the ice giants from measurements of the thermal IR spectrum and the progress in measurements to date. I will then turn to examine the possibilities and challenges for future spacecraft instrumentation seeking measure their spectra in the mid-IR, and some key technologies that will need to be developed.

Registration not yet open.

Questions? mallory.kinczyk@jhuapl.edu

Related Documents:

• Ice Giants Seminar Series Connection Information.pdf

July 9, 2024 11:00 - 12:00 EDT

Orbital Stability and Age of the Inner Moons of Uranus

Webinar Zoom Link

Presenter: Dr. Matja Cuk (SETI)
Abstract: Uranus has 13 small moons interior to Miranda, most of which were discovered during the Voyager 2 flyby. It has been known for decades that some of these moons, notably the Portia group, may be unstable against mutual collisions on <100 Myr timescales. As new moons discovered using HST were added to the Voyager-era system, it appeared that some of the new additions, notably Cupid, are unstable on sub-Myr timescales. I will present our recent results (Cuk et al. 2022, AJ) which suggests that the Belinda group (Cupid, Belinda, Perdita) is stable on 50+ Myr timescales due to a newly recognized orbital resonance between Belinda and Perdita. We also confirm that the Portia group (Desdemona, Cressida, Juliet, Portia) is ultimately unstable, as found in prior work. I will discuss the implications of the short dynamical lifetimes and the existence of the Belinda-Portia resonance for the age of the moons, including the possibility that the inner moons of Uranus experience episodes of disruption and re-accretion.

Registration not yet open.

Questions? mallory.kinczyk@jhuapl.edu

Related Documents:

• Ice Giants Seminar Series Connection Information.pdf

August 13, 2024 11:00 - 12:00 EDT

TBD

Webinar Zoom Link

Presenter: Dr. Jessica Weber (Caltech/JPL)

Registration not yet open.

Questions? mallory.kinczyk@jhuapl.edu

Related Documents:

• Ice Giants Seminar Series Connection Information.pdf