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Posts by dgmilewski

Eric Mamajek (JPL)

March 03 2017: A Transiting Extrasolar Ring System

Posted on Jan 4, 2017 in Seminars

I’ll discuss the discovery and characterization of the “J1407” (V1400 Cen) system and its eclipsing complex ring system. J1407 is an otherwise unremarkable ~15 Myr-old pre-main sequence solar-mass star lacking infrared excess. The disk/ring system transiting J1407 is tenths of an AU in size with approximate mass similar to that of the Earth, and the best models thus far require dozens of rings. The system is intermediate in size and mass between Saturn’s rings and circumstellar disks, and may represent the first example of a protoexosatellite disk and indirect evidence of exomoon...

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February 17, 2017: Ice Nucleation: From The Earth To Mars And Beyond

Posted on Jan 4, 2017 in Seminars

Ice nucleation in the Earth’s atmosphere is known to be an important factor in climate, chemistry, and precipitation. By mimicking that planet’s atmosphere, we can leverage tools for terrestrial studies of ice clouds to understand the Martian water and carbon cycles. Recent observations show clouds to be present around exoplanets as well. Although measurements are much more uncertain, these technologies can help elucidate the atmospheres of these distant planets.

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February 10, 2017: Evidence for aqueous alteration and ice-rock fractionation on (1) Ceres

Posted on Jan 4, 2017 in Seminars

Analyses of data acquired by the NASA Dawn mission show that the surface of large asteroid Ceres is rich in hydrogen in the form of phyllosilicates, water ice, and perhaps organic matter. Differences between Ceres’ surface elemental composition and that of the primitive CI chondrites suggest Ceres underwent ice-rock fractionation or formed from a different reservoir than the CI parent body. Composition data acquired by Dawn provide further constraints on Ceres’ origins, hydrothermal evolution, and present state, placing Ceres in context with other icy, solar system bodies.

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February 03, 2017: Characterizing Middle And Outer Solar System Minor Bodies As Probes For Solar System Evolution

Posted on Jan 4, 2017 in Seminars

Many current theories posit a period of chaotic dynamical alterations throughout the middle and outer Solar System, during which the orbital architecture of the gas and ice giants changed drastically and the remnant planetesimals from planet formation were scattered. Using photometry, spectroscopy, and magnitude distribution analysis to study the present-day minor bodies that occupy this region namely, Jupiter Trojans, Hilda asteroids, Kuiper Belt objects and Centaurs we can compare the properties of the various populations and begin to evaluate our understanding of Solar System evolution.

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January 27, 2017: Probing The Comet-Asteroid Continuum

Posted on Jan 4, 2017 in Seminars

The era of modern astronomy is unfortunately not long enough to cover the typical lifetime of comets. However, comets produce dust which is potentially detectable as meteor activity at the Earth. Here I discuss the effort to understand cometary aging by examining different parts of the evolution spectrum of Jupiter-family comets (JFCs) by combining telescopic and meteor observations.

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The iPLEX Winter 2017 Guest Speaker Schedule

Posted on Dec 27, 2016 in Seminars

The iPLEX Winter 2017 Guest Speaker Schedule: Please join us on Fridays from 12 to 1pm in UCLA Geology Building (Room 3-814), followed by lunch 1 to 2pm. The first and last days of classes for the Winter 2017 are January 9th 2017 and March 17th 2017, respectively.   Jan 13: No speaker/talk this week Jan 20: Margaret Pan (MIT) “Eccentric rings and disks” I’ll describe two observationally-motivated projects on eccentric systems of colliding particles. First, I’ll discuss a derivation for the mass of the rings orbiting the minor planet Chariklo, and some implications...

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The Disintegration of Comet 332P/Ikeya-Muramaki

Posted on Sep 15, 2016 in Featured, News

The Disintegration of Comet 332P/Ikeya-Muramaki

DATELINE: SEPT. 15, 2016, LOS ANGELES, CA. U.S.A. UCLA-led astronomers capture best view ever of disintegrating comet Astronomers have captured the sharpest, most detailed observations of a comet breaking apart 67 million miles from Earth, using NASA’s Hubble Space Telescope. The discovery is published online today in Astrophysical Journal Letters.In a series of images taken over three days in January 2016, Hubble revealed 25 building-size blocks made of a mixture of ice and dust that are drifting away from the comet at a leisurely pace, about the walking speed of an adult, said...

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EPSS’s Emmanuel Masongsong’s Figure Published in Nature Physics

Posted on Sep 15, 2016 in Featured, News

EPSS’s Emmanuel Masongsong’s Figure Published in Nature Physics

Image caption: An artist’s rendering of the magnetosphere in cross-section, with the sun and solar wind on the left and magnetic field lines emanating from the Earth in blue. The five THEMIS probes were well-positioned to directly observe one particular magnetic field line as it moved back and forth every six minutes. This magnetic field motion caused electrons (white dots) to stream along the field line and enter Earth’s north and south poles, brightening a specific region of the aurora. Credit: E. Masongsong, UCLA EPSS, NASA EYES.   Auroras Dance to the Pulse of Earth’s Magnetic...

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iPLEX-MUST Fellows Program in Planetary Science

Posted on Sep 15, 2016 in Featured, News

iPLEX-MUST Fellows Program in Planetary Science

  iPLEX-MUST Fellows Program in Planetary Science University Involvement Host Department: Institute for Planets and Exoplanets (iPLEX) Department of Earth, Planetary and Space Sciences (EPSS)   Contact: Prof. David Jewitt, Director of iPLEX, jewitt@ucla.edu Partnering University: Macau University of Science and Technology (MUST) Contact: Prof. Kwing Chan Lam, Director Space Science Institute, klchan@must.edu.mo The iPLEX-MUST Fellows Program Visitors (graduate students, postdocs and junior faculty) from the Macau University of Science and Technology (MUST) will, through extended stays at...

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Academies’ ‘Search for Life Workshop’ Registration Open (5-6 December 2016)

Posted on Aug 26, 2016 in Seminars

No events to display. The Space Studies Board of the National Academies of Sciences, Engineering, and Medicine is hosting a workshop and poster session to explore the current status of activities to detect extraterrestrial life in the solar system and extrasolar planetary systems. The workshop will feature presentations from experts on the environmental limits of life, habitable environments in the solar system and beyond, extraterrestrial biosignatures, and life detection techniques and instrumentation.   The workshop will take place at the Beckman Center in Irvine, CA on December...

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The iPLEX Fall 2016 Guest Speaker Schedule

Posted on Aug 19, 2016 in Seminars

The iPLEX Fall 2016 Guest Speaker Schedule: Please join us on Fridays from 12 to 1pm in the UCLA Geology Building (Room 3-814), followed by lunch 1 to 2pm. Sep 23: No speaker/talk this week Sep 30: Ana Piso (UCLA) “Origins of Gas Giant Compositions: The Role of Disk Location and Dynamics” The composition of planets is determined by and tightly linked to the composition of the protoplanetary disk in which they form. In the first part of my talk, I will discuss giant planet formation through core accretion. In the second part, I will explore how the composition and evolution of...

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