Josef Ďurech
A5009076447- Astro and Planetary Science
- Planetary Science and Exploration
- Stellar, planetary, and galactic studies
- Isotope Analysis in Ecology
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Atmospheric Ozone and Climate
- High-pressure geophysics and materials
- Space Exploration and Technology
- Geological and Geochemical Analysis
- Geology and Paleoclimatology Research
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Nuclear physics research studies
- Geomagnetism and Paleomagnetism Studies
- Air Quality Monitoring and Forecasting
- Space Satellite Systems and Control
- Geophysics and Gravity Measurements
- Calibration and Measurement Techniques
- Spacecraft and Cryogenic Technologies
- Laser-induced spectroscopy and plasma
- Impact of Light on Environment and Health
- Astronomical and nuclear sciences
- Nuclear Physics and Applications
- Atmospheric chemistry and aerosols
Charles University
2016-2025
Czech Academy of Sciences, Astronomical Institute
2015-2024
McDonald's (United States)
2023
Adıyaman University
2023
Odlewnie Polskie (Poland)
2023
Astronomical Institute of the Slovak Academy of Sciences
2009-2020
Institute of Astronomy
2009-2014
University of Helsinki
2005-2007
(Abridged) We describe here the most ambitious survey currently planned in optical, Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST have unique capability faint time domain. The design is driven four main themes: probing dark energy matter, taking an inventory Solar System, exploring transient optical sky, mapping Milky Way. wide-field ground-based system sited at Cerro Pach\'{o}n northern Chile. telescope 8.4 m...
A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of exciting science opportunities next decade. The Large Synoptic Survey Telescope (LSST) have an effective aperture 6.7 meters and imaging camera field view 9.6 deg^2, be devoted ten-year 20,000 deg^2 south +15 deg. Each pointing imaged 2000 times fifteen second exposures six broad from 0.35 1.1 microns, total point-source depth r~27.5. LSST Science Book describes basic...
<i>Context. <i/>Apart from a few targets that were directly imaged by spacecraft, remote sensing techniques are the main source of information about basic physical properties asteroids, such as size, spin state, or spectral type. The most widely used observing technique – time-resolved photometry provides us with data can be for deriving asteroid shapes and states. In past decade, inversion lightcurves has led to more than hundred models. next when all-sky surveys available, number models...
Context. In the past decade, more than one hundred asteroid models were derived using lightcurve inversion method. Measured by number of models, has become leading method for shape determination.
Context. Until recently, the 3D shape, and therefore density (when combining volume estimate with available mass estimates), surface topography of vast majority largest ( D ≥ 100 km) main-belt asteroids have remained poorly constrained. The improved capabilities SPHERE/ZIMPOL instrument opened new doors into ground-based asteroid exploration. Aims. To constrain formation evolution a representative sample large asteroids, we conducted high-angular-resolution imaging survey 42...
The Vera C. Rubin Observatory is expected to start the Legacy Survey of Space and Time (LSST) in early mid-2025. This multi-band wide-field synoptic survey will transform our view solar system, with discovery monitoring over 5 million small bodies.The final strategy chosen for LSST has direct implications on discoverability characterization system minor planets passing interstellar objects. Creating an inventory one four main science drivers. observing cadence a complex optimization problem...
Context. Near-Earth asteroid 162173 (1999 JU3) is a potential flyby and rendezvous target for interplanetary missions because of its easy-to-reach orbit. The physical thermal properties the are relevant establishing scientific mission goals also important in context near-Earth object studies general.
Disk-integrated photometric data of asteroids do not contain accurate information on shape details or size scale. Additional such as disk-resolved images stellar occultation measurements further constrain asteroid shapes and allow estimates. We aim to use all available about forty obtained by the Near-InfraRed Camera (Nirc2) mounted W.M. Keck II telescope together with disk-integrated photometry determine their volumes. can then volume, in combination known mass, derive bulk density....
Context. Asteroid modeling efforts in the last decade resulted a comprehensive dataset of almost 400 convex shape models and their rotation states. These already provided deep insight into physical properties main-belt asteroids or large collisional families. Going finer detail (e.g., smaller families, with sizes ≲20 km) requires knowledge parameters more objects.
Basaltic V-type asteroids are common in the inner part of Main Asteroid Belt and much less abundant mid outer parts. They scientific interest because they sample crusts mantles theoretically plentiful differentiated planetesimals that existed Solar System four billion years ago. Some theories suggest those objects formed terrestrial planet region were then implanted main asteroid belt. In consequence, we should observe a large number fragments multiple Belt. That is filled with fragments;...
Gaia Data Release 3 contains accurate photometric observations of more than 150,000 asteroids covering a time interval 34 months. With total about 3,000,000 measurements, typical number per asteroid ranges from few to several tens. We aimed reconstruct the spin states and shapes this dataset. computed viewing illumination geometry for each individual observation used light curve inversion method find best-fit model, which was parameterized by sidereal rotation period, axis direction,...
The larger number of models asteroid shapes and their rotational states derived by the lightcurve inversion give us better insight into both nature individual objects whole population. With a statistical sample we can study physical properties populations, such as main-belt asteroids or families, in more detail. Shape also be used combination with other types observational data (IR, adaptive optics images, stellar occultations), e.g., to determine sizes thermal properties. We use all...
We introduce ADAM, the All-Data Asteroid Modelling algorithm. ADAM is simple and universal since it handles all disk-resolved data types (adaptive optics or other images, interferometry, range-Doppler radar data) in a uniform manner via 2D Fourier transform, enabling fast convergence model optimization. The resolved can be combined with disk-integrated (photometry). In reconstruction process, difference between each type only few code lines defining particular generalized projection from 3D...
The JAXA Hayabusa-2 mission was approved in 2010 and launched on December 3, 2014. spacecraft will arrive at the near-Earth asteroid 162173 Ryugu 2018 where it perform a survey, land obtain surface material, then depart Dec 2019 return to Earth 2020. We observed with Herschel Space Observatory Apr 2012 far-IR thermal wavelengths, supported by several ground-based observations optical lightcurves. reanalysed previously published Subaru-COMICS AKARI-IRC merged them Spitzer-IRS data set. In...
Asteroid (16) Psyche is the target of NASA mission. It considered one few main-belt bodies that could be an exposed proto-planetary metallic core and would thus related to iron meteorites. Such association however challenged by both its near- mid-infrared spectral properties reported estimates density. Here, we aim refine density set further constraints on bulk composition determine potential meteoritic analog. We observed with ESO VLT/SPHERE/ZIMPOL as part our large program (ID 199.C-0074)....
We use the lightcurve inversion method to derive new shape models and spin states of asteroids from sparse-in-time photometry compiled in Lowell Photometric Database. To speed up time-consuming process scanning period parameter space through convex models, we distributed computing project Asteroids@home, running on Berkeley Open Infrastructure for Network Computing (BOINC) platform. This way, period-search interval is divided into hundreds smaller intervals. These intervals are scanned...