Date 1pm, Friday, 14/08/15
Speaker Noémi Kinga Zsámberger (ELTE, Dept of Astronomy)
Title A dynamical examination of the 5:2 resonance in the Trans-Neptunian domain.
Venue ATOMKI Bldg Nr I, Videoconference and Seminar Room
Abstract Trans-Neptunian Objects (TNOs) are icy-rocky objects of various sizes, which move around the Sun beyond the orbit of Neptune in the so-called Edgeworth-Kuiper belt. Aside from their most well-known representative, the dwarf planet Pluto, over a thousand such minor planets are cataloged, and new discoveries are still to be made in the area. A more thorough exploration and better understanding of the characteristics of TNOs can also contribute to our knowledge of the processes shaping solar systems (including our own) all through their existence. The current examination was dedicated to a detailed mapping of a narrower area of the field, namely, the dynamical parameters of the 5:2 resonance zone.

First, we will introduce the Edgeworth-Kuiper belt itself, and provide a short summary of the resonance phenomenon, which is one of the primary factors shaping the structure of the Trans-Neptunian domain. Next, we will discuss the findings of the numerical simulations we used in order to map Neptune's 5:2 mean motion resonance zone. Various interesting results will be covered, such as the broadening of the domain resonant TNOs may occupy in the a-e (semi-major axis – orbital eccentricity) plane, or the regularities discovered in the initial orbital elements M (mean anomaly) and ω (argument of pericenter) leading to resonant behaviour. We look forward to presenting the meaning of these findings, as well as how they relate to our preexisting knowledge of the Trans-Neptunian belt.
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Date 1pm, Wednesday, 12/08/15
Speaker Talwinder Singh (Indian Institute of Technology (BHU), Varanasi, India)
Title Role of multiple viewpoints of STEREO mission in space weather and Coronal seismology applications.
Venue ATOMKI Bldg Nr I, Videoconference and Seminar Room
Abstract Coronal mass ejections (CMEs) are one of the major reasons of severe space weather conditions and the prediction of their arrival time on Earth is a major challenge for Space scientists. After the launch of STEREO Ahead and Behind spacecraft, the tracking of CMEs has improved a lot. We will discuss how multiple viewpoints of STEREO mission helps in getting different physical parameters of CMEs. We will also discuss how STEREO data can be used in the field of Global coronal seismology to better understand the structure of solar corona.
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Date 1pm, Wednesday, 05/08/15
Speaker Tamás Sándor Kiss (U. of Sheffield, UK)
Title New animals of the solar zoo - The macrospicules
Venue ATOMKI Bldg Nr I, Videoconference and Seminar Room
Abstract The recently launched Solar Dynamics Observatory (SDO) satellite provides fantastic new oppurtunities for a better understanding of small-scale solar chromospheric jets, e.g. spicules and macrospicules. These plasma ejecta are collimated cool and dense magnetised solar material lifting off the solr surface at any moment of time, determining the Solar Wind. Thanks to the uniquely available high spatial and temporal resolution observations -provided by the Atmospheric Imaging Assembly's (AIA) camera on-board SDO- we constructed an extensive macrospicule dataset covering the period of June 2010 and December 2014 detected at 30.4 nm wavelength. First, we will introduce solar ejecta, with a focus on spicules and macrospicules. Next, we will discuss our results found during a careful and detailed investigation of this dataset. Several promising outcomes such as e.g. the temporal variation of the maximum physical length of the macrospicules, which shows a nearly two-year long oscillation, will be discussed. These observations may be paradigm-changing as far as the solar dynamo theory, i.e. the driver of Space Weather, is concerned. Therefore we look forward to outline some exciting possibilities of the meaning of these observations.
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