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Nowe dane na temat wystąpień szkarłupni w wapieniu muszlowym (środkowy trias) Górnego Śląska

Paszcza Karolina

Przegląd Geologiczny

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2024

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Vol. 72, nr 4

156--161

EN

In the Sadowa Góra quarry in Jaworzno, southern Poland, the Muschelkalk deposits are exposed (Lower and Upper Gogolin Beds). The occurrence of echinoderms seems to be particularly interesting. The isolated ossicles of asteroids were found already in the 1st Wellenkalk of the Lower Gogolin Beds (Aegean), which is one of the oldest post-Paleozoic occurrence in the world. Until recently, it was believed that the first echinoids appeared in the Germanic Basin during the Bithynian (above the Conglomeratic Horizon of the Upper Gogolin Beds). Currently, they have been found, similarly to the remains of asteroids, already in the 1 st Wellenkalk. Attention was also drawn to the fact that the stratigraphically important crinoid species Holocrinus dubius may have appeared in Upper Silesia earlier than previously thought.

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Górnictwo pozaziemskie w Polsce

Przylibski Tadeusz A., Łuszczek Katarzyna, Blutstein Konrad, Szczęśniewicz Mateusz, Ciapka Dominika

Przegląd Górniczy

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2022

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T. 78, nr 3

17--24

PL

Autorzy przedstawili aktualny na połowę 2022 roku stan szeroko rozumianego górnictwa pozaziemskiego w Polsce. Analiza autorów objęła wszelkie inicjatywy, projekty i badania, które dotyczą różnych aspektów eksploracji pozaziemskich ciał Układu Słonecznego pod kątem rozpoznania i wykorzystania znajdujących się na nich złóż różnorodnych surowców. W Polsce mamy obecnie wiele możliwości rozwoju sektora górnictwa pozaziemskiego. Sytuacja ta jednak w najbliższym czasie będzie się pogarszać, jeśli nie zostaną stworzone warunki do rozwoju tej dziedziny wiedzy i przemysłu. Oczywiście istotne jest zainwestowanie odpowiednich środków finansowych, ale także wykreowanie odpowiedniej polityki rozwoju i podjęcie kompleksowych działań sprzyjających rozwojowi dydaktyki i nauki w zakresie górnictwa i górnictwa pozaziemskiego. Równie istotne jest także wspieranie, a najlepiej realizowanie spójnej koncepcji rozwoju górnictwa pozaziemskiego, jako bardzo istotnej części przemysłu sektora kosmicznego.

EN

The Authors presented the current state of the broadly understood extraterrestrial mining in Poland in mid-2022. The authors’ analysis covered all initiatives, projects and research that relate to various aspects of the Solar System’s extraterrestrial bodies exploration in terms of the identification and use of various raw materials on them. Currently we have many opportunities for the development of the extraterrestrial mining sector in Poland. However, this situation will deteriorate in the near future, if the conditions for the development of this field of knowledge and industry are not created. Of course, it is crucial to invest appropriate funds, but also to create an appropriate development policy and undertake comprehensive activities conducive to the development of teaching and science in the field of mining and extraterrestrial mining. It is also equally important to support, and preferably implement, a coherent concept for the development of extraterrestrial mining as a significant part of the space sector industry.

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The Potentially Hazardous Asteroid (410777) 2009 FD

Wlodarczyk I.

Acta Astronomica

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2015

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Vol. 65, No. 2

215--231

EN

The asteroid (410777) 2009 FD is placed at the top of the JPL NASA Sentry Risk Table. We show that the predicted probability of the potential impact of the asteroid (410777) 2009 FD in fact depends on (i): used methods of selection and weighing of observational data, (ii): adopted dynamical model with included non-gravitational effects in the motion of asteroid based on cometary approach, and considerably weaker depends on (iii): the used model of the Solar System with different number of massive asteroids as potential perturbers. We computed impact solutions of the asteroid (410777) 2009 FD based on its 296 optical observations from February 24, 2009 to April 02, 2014 and one radar observation from April 07, 2014. We used the freely available ORBFIT Software Package and studied the future evolution of the orbit of (410777) 2009 FD searching for close approaches with the Earth and for the possible impacts up to the year 2200. According to our study the impacts are possible in the years: 2185, 2186, 2190, 2191, 2192, 2194, 2196, and 2198, provided the non-gravitational parameter A2 in the range of (-46.0,+3.0)×10-15 a.u./d2, with the gap between (-25.0,-11.0)×10-15 a.u./d2.

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Error Propagation of the Computed Orbital Elements of Selected Near-Earth Asteroids

Włodarczyk I.

Acta Astronomica

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2007

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Vol. 57, No. 1

103--121

EN

Computed orbital elements of asteroids contain errors depending on the errors of observations. In accordance with the procedure described by Sitarski (1998) we can find randomly selected sets of orbital elements which reasonably represent all observations with fixed mean rms residual. In this way we can obtain the error ellipse of the initial orbital elements, and that of the predicted ones. By integrating equations of motion of these computed clones we can obtain a time evolution of changes of the shape of the torus, inside which all the orbits of the clones exist. The time evolution of the configuration of the torus and its size are connected with the asteroid position inside this torus. The larger is the torus the more difficult it is to find the position of the asteroid. The shape of the torus and its time evolution depend mainly on the kind of the asteroid's orbit. If the orbit is more chaotic, then changes of the torus shape are more rapid and the size of the torus is larger. Close approaches of asteroids to planets are the main source of the chaotic motion. This is particularly important in computing their close approaches to Earth. The distances between the minor planet on the nominal orbit and the virtual minor planets around the nominal orbit can attain considerable values. In this work we computed the time necessary for the values of the mean distances of the clones to achieve the dimensions of the Earth radius. In this respect, we investigated the motion of the known earlier asteroids 433 Eros and 1943 Anteros, and the recently discovered minor planets 99942 Apophis (2004 MN4) and 2004 VD17 - the most dangerous to the Earth, according to the Impact Risk Page of NASA (http://neo.jpl.nasa.gov/risk/). It appears that time-span after which dimensions of the torus attain well defined values are strongly correlated with the stability time and they are also connected with frequent and close approaches to the planets. Furthermore, it was investigated whether the computed orbital elements of the asteroids for the epoch of the beginning, middle or end of the observation, influence the behavior of the asteroids. Also the propagation of the region of uncertainty of asteroid position was computed. This can simplify the computing of close approaches of these asteroids to the Earth and the impact risk assessment.

5

Stability of the Most Hazardous Mars-Crossers

Kankiewicz P., Włodarczyk I.

Acta Astronomica

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2006

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Vol. 56, No. 4

413--425

EN

The equations of motion of 4190 Mars Crossers (MCs) were numerically integrated to analyze their all possible close approaches to planets in the next 104 years. A sample of asteroids potentially hazardous to Mars was selected and properties of their chaotic motion on larger time scales were determined. For samples of MCs closely approaching Mars, their mean frequency of close encounters was computed. We also analyzed the presence of mean motion and secular resonances. The population of asteroids hazardous to Mars was found and the influence of frequent close approaches and resonances on the stability of their trajectories was estimated. We also estimated the correlation between the frequency of close approaches to Mars and the Lyapunov Time (LT) of these asteroids. Some results concerning the correlation between mean motion/secular resonances and LT were also presented as well as three selected examples of dynamically interesting MCs.

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Generating of "Clones" of an Impact Orbit for the Earth-Asteroid Collision

Sitarski G.

Acta Astronomica

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2006

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Vol. 56, No. 3

283--292

EN

If we find an impact orbit of the Earth-crossing asteroid we can determine the impact point location on the Earth surface. If we want to find other orbits, very similar to the impact one, we have to select randomly a number of such "clones" and to integrate equations of motion many times from the osculation epoch to the collision date. Then we can determine a path of hypothetical impact points on a map of the Earth. We elaborated a method allowing us to avoid the repeating of long-term integration. The method is based on a special feature of the cracovian least squares correction applied to the random orbit selection. After finding the impact orbit we randomly select an arbitrary number of "clones", perform only one time-consuming integration, and find quickly many similar impact orbits for the collision date. We applied our method for four chosen asteroids: 2004 VD17, 1950 DA, Apophis (2004 MN4), and Hathor. We show that we are able to "clone" the impact orbit in a very difficult case and when it is impossible to do this in another way.

7

Librations with Mass Transfer in the Sun-Jupiter System

Horedt G. P., Oproiu T.

Acta Astronomica

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2005

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Vol. 55, No. 3

321--329

EN

Trojan-type motion is analytically and numerically studied under mass transfer between the primaries with conservation of their total orbital angular momentum. We prove theoretically and numerically our new result that angular libration widths change as m1/4, (m - Jupiter mass) if they are throughout smaller than about 60°. Numerical examples show that for initial libration widths larger than about 60°, the Trojan is ultimately driven out of the libration domain, becoming an ordinary asteroid, if Jupiter's transferred mass increases by a factor less than about two. Certain processes occurring in our solar system and in extrasolar planetary systems lead to a decrease of the Trojan's libration amplitude, while other processes lead to an increase, respectively.

8

2060 Chiron - Chaotic Dynamical Evolution and its Implications

Gabryszewski R.

Acta Astronomica

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2002

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Vol. 52, No. 3

305--216

EN

2060 Chiron - one of the Centaurs orbiting chaotically among the giant planets - is treated as an asteroid and a comet (95P/Chiron) as well. Since the day of the discovery many papers have discussed its past and future fate. In this paper a possibility of Chiron's dynamical evolution to different cometary orbital types is studied. An ensemble of orbital elements was used to describe Chiron's dynamics in terms of probability. The ensemble was generated using a unique scheme of elements creation. Dispersion of elements obtained by this method is much smaller compared to ranges obtained by varying the original elements in the ellipsoid of their mean errors. The chaos in Chiron's dynamical evolution can be seen in 5 to 9 kyrs, although the dispersion of orbital elements is small. Halley type orbits are the rarest noticed orbital types but the number of these objects is three times greater than the number of apparent Halley type comets. The variations of probability of different cometary orbits as a function of time is also presented. The rate of HTC orbit production is only four times lower than the production rate of JFCs after the first 50 kyrs of integration. Remarks on the small body transportation mechanisms are also included.

9

Obraz Układu Słonecznego na przełomie tysiącleci

Ziołkowski K.

Przegląd Geofizyczny

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2001

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Z. 1-2

67-79

EN

A general outline of the modern view of the Solar System is presented. Special attention is given to the consequence of the last discoveries of various types of asteroids and comets. Dynamical history of those small bodies plays an important part in the evolution of the Solar Systems.

10

Comparative analysis of the Baszkówka and Mt. Tazerzait chondrites: genetic conclusions based on astrophysical data and the mineralogical and petrological data

Pilski A. S., Przylibski T. A., Zagożdżon P. P.

Geological Quarterly

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2001

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Vol. 45, No 3

331-342

EN

The L5 chondrites Baszkówka and Mt. Tazerzait are characterised. Their astronomical, mineralogical and petrological characteristics confirm that these meteorites are similar. They could be derived from the same parent body, though from the different depths below its surface. A third meteorite - the Tjerebon - might have arisen from the same swarm of meteoroids. The parent body to these meteorites in the asteroid belt can not be established at present. The porosity, of these chondrites suggests that they formed close to the surface of their parent asteroid. The process of formation of the parent rock of the Baszkówka chondrite is similar in some respects to sedimentation of a weakly compacted terrestrial sandstone. Thus, a two-stage geological history may be envisaged: firstly formation of the component minerals and mineral aggregates of this meteorite. Then, later in a different environment, the accretion of fragments of this parent material, together with a small amount of matrix, into a strongly porous sedimentary rock.

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Prediction of the Motion of Asteroids and Comets Over Long Intervals of Time

Włodarczyk I.

Acta Astronomica

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2001

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Vol. 51, No. 4

357--376

EN

Difference of the mean anomalies of two starting orbits of a minor planet or a comet which only differ by an error of calculating of one of the orbital elements grows rapidly with time. This means that it is almost impossible to predict behavior of minor planets or comets on the orbit outside the period of time called the time of stability in our work. The time of stability for some selected minor planets and comets are given. For some minor planets and comets the time of stability is surprisingly short, about several hundreds years only.

12

Motion of the Dangerous Asteroid 1997 XF11

Sitarski G.

Acta Astronomica

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1999

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Vol. 49, No. 1

103--112

EN

Minor planet 1997 XF11, discovered in December 1997, is moving in the heliocentric orbit which almost intersects the Earth orbit. In October 2028 the asteroid will approach the Earth to within 0.006 a.u. We improved the asteroid's orbit on the base of 151 astrometric observations from 1990-1998. To investigate the long-term motion of the asteroid we randomly selected 500 sets of orbital elements and numerically integrated the equations of motion by the recurrent power series. We followed evolution of minimum distances between orbits of 1997 XF11 and the Earth for moments of consecutive passages of the asteroid through its descending node. We found that only in 2042 the minimum distance between orbits of both planets could be smaller than the Earth radius. However, the asteroid will pass through its descending node in July 2042 while a collision with the Earth could happen during the October encounter. After 2042 the minimum distance between orbits of both planets will be permanently growing up, and hence we estimate that during the next several thousand years collision with the Earth will be impossible. We also investigated the asteroid's motion before 1990. We found that past close approaches of 1997 XF11 to the Earth occurred in 1971 to within 0.032 a.u. and in 1957 to within 0.015 a.u. We calculated ephemerides of the asteroid for those past approaches aiming at finding some old observations of the minor planet. We have also studied accuracy of prediction of the future motion of 1997 XF11 based, however, on 142 observations of the asteroid from 1997/98 only. We found that in that case possibility of collision during 2030-2050, although possible, is completely unpredictable.

13

How to Find an Impact Orbit for the Earth-Asteroid Collision

Sitarski G.

Acta Astronomica

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1999

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Vol. 49, No. 3

421--431

EN

The Earth-crossing asteroids can approach the Earth at dangerously small distances. If the observation arc of a single apparition orbit is short the determined orbital elements and hence a prediction of the future encounter with the Earth are uncertain. We presented the method of finding an impact orbit by the least squares correction with the "forced" equality constraints. As a solution we obtain: (i) initial values of rectangular coordinates and velocity components (and hence the orbital elements) allowing the asteroid to collide with the Earth, and (ii) the minimum value of the \it rms residual resulting from the impact orbit. The latter value is very important since it may serve as a kind of measure of probability of the collision, and in any case it allows us to exclude a possibility of the expected catastrophe. We performed computations of the impact orbits for two asteroids: 1997 XF11 and 1999 AN10. We found two impact orbits for hypothetical collisions of 1997 XF11 with the Earth in 2028 and 2033, and four orbits for 1999 AN10 colliding with the Earth in 2027, 2034, 2036, and 2039. Based on the 101 observations of 1999 AN10 from 1999 Jan. 13 - May 16, we show that its collision with the Earth in 2027 is impossible, but in 2039 it would be more probable. We made also a numerical simulation of the fictitious asteroid which would certainly collide with the Earth. We show that in this case we can easily find the impact orbit, and the rms value evidently does not allow us to exclude a possibility of the collision.

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Motion of the Minor Planet 4179 Toutatis: Can We Predict Its Collision with the Earth?

Sitarski G.

Acta Astronomica

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1998

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Vol. 48, No. 3

547--561

EN

Minor planet 4179 Toutatis is an Apollo type object with a very small orbit inclination (i=0°.47), hence it has a possibility to approach closely the Earth (an encounter to within 0.01 a.u. is expected in 2004) and might be a good candidate for a future collision with the Earth. We collected 640 astrometric observations of Toutatis from the period 1934-1997 to improve the orbit. We had to include a nongravitational term into equations of motion expressed by a secular change a of the semi-major axis a of the Toutatis orbit to obtain a fully satisfactory solution of the orbit determination. A value a=-0.16×10-10 is two orders smaller than that determined in the case of short-period comets with known nongravitational effects. To investigate the long-term motion of Toutatis we numerically integrated the equations of motion by recurrent power series taking into account perturbations caused by the eight planets from Mercury to Neptun, treating the Earth and Moon as separate bodies, and also by the four biggest asteroids. We randomly varied the orbital elements to examine the Toutatis' motion for a number of different orbits. We present a new method of the random orbit selection which allows us to find a set of different orbits but representing well all the observations used for the orbit correction. Our results confirm a conclusion found by other authors that Toutatis orbit is exceptionally chaotic. Therefore, we are not able to predict the motion of Toutatis further than for 300 years. However, our integrations spanning 1500 years showed that the evolution of position of the descending node of Toutatis' orbit might go also in such a direction that the orbits of Toutatis and of the Earth would intersect in the future. Hence a possibility of the Toutatis-Earth collision is not excluded but it is completely unpredictable. To investigate conditions of a hypothetical collision of a minor planet with the Earth we made the following numerical simulation. Based on the Toutatis' orbit we deduced such orbital elements for a fictitious minor planet "Fatum" that a shape of the orbit was very similar to that of Toutatis, but we knew in advance that "Fatum" would certainly collide with the Earth in September 2004 and we calculated values of the impact parameters. We created a set of 638 artificial observations of "Fatum" in 1988-1997 for the same dates and with the same random observational errors like those of Toutatis. Then we corrected the "Fatum's" orbit for different observational intervals to examine the exactness of the impact prediction in 2004. We found that in 1993 we would be sure that the collision is inevitable, and in 1997 we could determine an impact area on the Earth's surface in range of a square of 100×100 km. We show that if we knew the impact date so early we could undertake an action to avoid the collision by trying to change the "Fatum's" heliocentric velocity only by one cm/sec.