Found 10 talks width keyword asteriods
Abstract
Simons Observatory (SO) is a new Cosmic Microwave Background telescope currently under construction in the Atacama Desert, close to ALMA and other recent CMB telescopes. It will have six small aperture (42cm) telescopes (SATs), and one large aperture (6m) telescope (LAT), observing at 30-280GHz (1-10mm) using transition edge sensors (TES) and kinetic inductance detectors (KIDs). As well as observing the polarisation of the CMB to unprecedented sensitivity, the LAT will perform a constant survey at higher angular resolution, enabling the systematic detection of transient sources in the submm, with large overlap of optical surveys such as LSST, DESI and DES. As well as giving an overview of SO, I summarise the types of transient sources that are expected to be seen by SO, including flaring stars, quasars, asteroids, and man-made satellites.
Abstract
The "Asteroid Terrestrial-impact Last Alert System" (ATLAS) is funded by NASA to find dangerous asteroids before they strike the Earth. It has operated from two Hawaii sites since 2015 and will very soon have South Africa and Chile sites to cover the entire visible sky every night four times to a limiting magnitude of m~19.5 per exposure. The process of finding asteroids leads to auxiliary data products along the way including accurate photometry of all stars in the sky and detection of flares and transients. I will describe ATLAS, how we approach our NASA mission to find NEOs, how ATLAS fits in with other ongoing or planned surveys, some of the data products that are available now, and the many new scientific opportunities that are emerging and waiting to be exploited. Time will be reserved at the end of the talk for some real time demonstrations: audience participation is encouraged. References include 2018PASP..130f4505T, our public web page at fallingstar.com and fallingstar.com/weather/ to see our current fisheye and webcam views at all four sites.
Zoom link: https://rediris.zoom.us/j/82241288569?pwd=QmtUWkNoRHNvYlk3dWJhRCtCdE1RQT0
Meeting ID: 822 4128 8569
Passcode: 776606
Youtube: https://youtu.be/Ax-70hAibow
Abstract
Series: XXVIII Canary Islands Winter School of Astrophysics: Solar System Exploration
Topic: Cometary Science and the Rosetta Mission.
Lecture 2: Rosetta, a voyage to a comet and to our origins.
In this second talk, Dr. Küppers gives an overview of the Rosetta mission, from its launch in 2004 until the end of the mission, in September 2016, only a month before the celebration of this Winter School. The talk includes information on the instruments on-board the spacecraft, the two fly-byes to asteroids Steins and Lutetia, and the results obtained from the observations of comet 67P/C-G.
Abstract
Series: XXVIII Canary Islands Winter School of Astrophysics: Solar System Exploration
Topic: Physical Properties of Asteroid Surfaces
Lecture 2: Novel spectrometric modeling
In his second talk, Dr. Muinonen focuses on multiple scattering, describing in detail processes such as the radiative transfer and coherent backscattering (RT-CB), particular cases with incoherent fields, and radiative transfer with reciprocal transactions (R2T2). He also presents very preliminar and recent results obtained by his team at the University of Finland on incoherent backscattering experimetns on millions of spherical particles. In this talk he also revisits space weathering in the context of radiative transfer theory and presents some experiments carried out with olivine.
Abstract
Series: XXVIII Canary Islands Winter School of Astrophysics: Solar System Exploration
Topic: Physical Properties of Asteroid Surfaces
Lecture 1: Introduction to asteroid UV-VIS-NIR spectrometry
In this first talk, Dr. Muinonen gives an introduction to polarimetry, photometry, and spectropolarimetry techniques and their application to the study of asteroid surfaces. The talk includes a description of the Shkuratov radiative transfer model and the use of Monte Carlo simulations to model radiative transfer for meteorite spectra.
Abstract
On February 15, while we were preparing to observe the close approach of the potentially hazardous asteroid (PHA) 2012 DA14 another small asteroid entered the Earth’s atmosphere over Russia. The object, of about 17m in diameter and 11.000 tons exploded in the atmosphere generating a bright flash, a powerful shock wave and small fragmentary meteorites. About 1500 people were injured because of the shock wave effects in the city of Chelyabinsk located east of the Ural Mountains and on the border of Europe and Asia. The more than 400 kilotons released suggest that this was largest asteroid that entered the Earth atmosphere since the 1908 Tunguska event.
The differences between the orbits of DA14 and the asteroid that caused the Chelyabinsk event showed that both objects are not related. The composition of the meteorite and the spectrum of DA14 we obtained with the GTC also support that.
In this talk I will resume all the information about the Chelyabinsk event and discuss the relevance of studying the near-Earth asteroids, in particular the PHAs, and present the main results of our study of asteroid DA14 (de León et al. 2013). I will also discuss the relevance of space mission studies on this objects and resume our participation in MarcoPolo-R and AIDA missions.
Abstract
Traditionally, astronomers study stars and planets by telescope. But we can also learn about them by using a microscope – through studying meteorites. From meteorites, we can learn about the processes and materials that shaped the Solar System and our planet. Tiny grains within meteorites have come from other stars, giving information about the stellar neighbourhood in which the Sun was born.
Meteorites are fragments of ancient material, natural objects that survive their fall to Earth from space. Some are metallic, but most are made of stone. They are the oldest objects that we have for study. Almost all meteorites are fragments from asteroids, and were formed at the birth of the Solar System, approximately 4570 million years ago. They show a compositional variation that spans a whole range of planetary materials, from completely unmelted and unfractionated stony chondrites to highly fractionated and differentiated iron meteorites. Meteorites, and components within them, carry records of all stages of Solar System history. There are also meteorites from the Moon and from Mars that give us insights to how these bodies have formed and evolved.
In her lecture, Monica will describe how the microscope is another tool that can be employed to trace stellar and planetary processes.
Abstract
Understanding the composition and the nature of any asteroid approaching the Earth, and consequently potentially hazardous, is a matter of general interest, both scientific and practical. The potentially hazardous asteroid 1999 RQ36 is especially accessible to spacecraft and is the primary target of NASA's OSIRIS-REx sample return mission. Spectra of this asteroid point to the most primitive meteorites (CIs and CMs) as the most likely analogs. Asteroid (3200) Phaethon is also particularly interesting. Together with 2005 UD and 2001 YB5, is one of the only 3 near-Earth asteroids with associated meteor showers, which mostly come from comets. There is evidence of the presence of hydrated minerals on its surface, usually associated with organic material. Both asteroids are classified as "B". B-type asteroids are found mostly in the middle and outer main belt and are believed to be primitive and volatile-rich. We combine dynamical and spectral information to identify the most likely main-belt origin of these two objects.
Abstract
In this talk we present spectroscopy of asteroids 24 Themis and 65 Cybele in the 2-4 μ region obtained with the NASA 3.5m IRTF telescope. Their spectra are very similar, and present the typical water ice band at 3.1 μ and additional absorption bands in the 3.2-3.4 μ region that can be attributed to solid organics, showing that there is a small amount of water ice and solid organics widely distributed across their surface. Spectra in the 6-25 μ region obtained with SPITZER of 65 Cybele also show that its surface is covered by a fine anhydrous silicate grains mantle as other outer belt asteroids like the Trojans are. This dust mantle, with a small amount of water ice and complex organic solids, is similar to comet surface where non-equilibrium phases coexist. The presence of water-ice and anhydrous silicates is indicative that hydration did not happened or is incomplete, suggesting that the temperatures were always sufficiently low. This is the first detection of water ice and and solid organics in the surface of an asteroid and suggest that these materials are much more abundant than expected in the surface of asteroids with semi-major axis a > 3 AU. The cosmogonical and astrobiological relevance of this discovery will be discussed.Abstract
Radar observation of near-Earth asteroids (NEAs) reveal the size, shape, spin characteristics of the population of small bodies near the Earth. Although spacecraft missions may give higher resolution images, they are infrequent and expensive. Only through ground based observations can we hope to understand the diverse population of NEAs. Radar imaging reveals surface features and shape at up to 7.5-m resolution. We see a surprising variety of object shapes, which tells us about their formation and evolution. Binary NEAs are easily detected using radar regardless of viewing geometry, the characteristics of which have led to new ideas about NEA evolution and internal structure. Craters and other surface concavities are often visible in radar images, unlike lightcurve-based shape models. Although opportunities to observe comets with radar are rare, more than ten comet nuclei have been detected to date, three with high resolution imaging. Radar observations have played an important role in a number of key areas in small body science, some of which will be discussed in this talk.
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