Spectral properties of near-Earth objects with low-Jovian Tisserand invariant

ABSTRACT The near-Earth objects with low-Jovian Tisserand invariant (TJ) represent about 9 per cent of the known objects orbiting in the near-Earth space, being subject of numerous planetary encounters and large temperature variations. We aim to make a spectral characterization for a large sample of NEOs with TJ ≤ 3.1. Consequently, we can estimate the fraction of bodies with a cometary origin. We report new spectral observations for 26 low-TJ NEOs. The additional spectra, retrieved from different public data bases, allowed us to perform the analysis over a catalogue of 150 objects. We classified them with respect to Bus-DeMeo taxonomic system. The results are discussed regarding their orbital parameters. The taxonomic distribution of low-TJ NEOs differs from the entire NEOs population. Consequently, TJ ∼ 3 can act as a composition border too. We found that 56.2 per cent of low-TJ NEOs have comet-like spectra and they become abundant (79.7 per cent) for TJ ≤ 2.8. 16 D-type objects have been identified in this population, distributed on orbits with an average TJ = 2.65 ± 0.6. Using two dynamical criteria, together with the comet-like spectral classification as an identification method and by applying an observational bias correction, we estimate that the fraction of NEOs with a cometary nature and H ∈ (14, 21) mag has the lower and upper bounds (1.5 ± 0.15) and (10.4 ± 2.2) per cent. Additionally, our observations show that all extreme cases of low-perihelion asteroids (q ≤ 0.3 au) belong to S-complex.

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lnformatiestromen en gegevensbanken inde parlementaire werkzaamheden

Res Publica ◽

10.21825/rp.v31i2.18877 ◽

1989 ◽

Vol 31 (2) ◽

pp. 181-188

Author(s):

Louis Vanvelthoven

Keyword(s):

Data Base ◽

Information Flow ◽

Telephone Network ◽

The Other ◽

Direct Access ◽

External Information ◽

Data Bases ◽

The Public ◽

Public Data ◽

Set Up

Opening up as many sources of information as possible is particularly conducive to the development of workable policy plans and to efficient decision-making in a democratic political system. It follows that MPs can greatly benefit from using computerized information systems.As far as the parliamentary activities are concerned, we can distinguish between internal and external information flow. The contents of the parliamentary documents, the procedure for processing them and the information on the parliamentary control are part of the internal information flow. The external information on the other hand refers to the relations between the MPs and the executive and the judiciary branches, supranational and international institutions as well as the library.To date, the House of Representatives has been the only assembly that has set up a computerized information system . The data bases of the House comprise : the parliamentary documents and the state of advancement of all proceedings linked to these documents (bath in the House and in the Senate) until the publication of the text in the official state journal. Other databases relate to the parliamentary control : interpellations, motions, oral questions and the entire text of the written parliamentary questions.The record of the House will also be stored in a data base giving references. The library fund has been integrated in the interlibrary network DOBIS-LIBIS. A data base was also designed for the press information, and linked to an image processing system.What has been realized in the House to date must also be feasible for the other parliamentary assemblies. Viewed from that perspective, it seems advisable that data bases be centralized in one parliamentary information DP centre. Access to this centre should be particulary user-friendly and uniform, so much so that all MPs can make maximum use of it.The system set up by the House meets with an ever increasing demand from other possible users. In this context, attention should be drawn to the interconnection of this system with other parliamentary assemblies, the extension of the system to other users in the House ofthe MPs and the external access to the system via the telephone network: direct access for the universities, and for certain public and private institutions and individual MPs, and the BISTEL and/ or VIDEOTEX access.The majority of the public data bases linked to the telephone network can be interrogated via the BISTEL system, hut many interesting applications are not accessible via the telephone network as they function in closed circuits.Opening up data bases by linking them to the telephone network, implies that the problem of cost and privacy be carefully examined. As to privacy, we should reflect on the public or confidential character of the data and its consequences, on safeguarding the information stored in the system and on the evolution ofcommunications technology from the perspective of a continental European communications network.

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Correspondence, Unpublished Papers and Data: Present making of Historical Records

International Astronomical Union Colloquium ◽

10.1017/s0252921100003298 ◽

1989 ◽

Vol 110 ◽

pp. 168-170

Author(s):

Anne-Marie Motais de Narbonne

Keyword(s):

Small Groups ◽

Research Process ◽

Historical Records ◽

Data Bases ◽

Technological Research ◽

Research Production ◽

Personal Involvement ◽

Public Data ◽

Fundamental Research ◽

Astronomical Research

Research process generates public and formal informations accessible through published documents or public data bases which libraries are used to deal with. It also generates informal, anachieved informations in format of correspondances, notes, calculus, reports, drawings... or other unpublished documents that libraries must not either leave aside.Since fundamental research, versus technological research for instance, implies great personal involvement, informal informations are mainly issued from individuals or small groups of individuals. It is probably the reason why this kind of informations and documents is often considered erronously as private by astronomers deciding by themselves to destroy, to move or leave behind their so-called personal papers. These documents and informations actually belong to the institutions. They must be preserved because they are part of the research production and also because they may be used for astronomical research as it is illustrated in S. Débarbat’s communication.

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Rat gene mapping using PCR-analyzed microsatellites.

Genetics ◽

10.1093/genetics/131.3.701 ◽

1992 ◽

Vol 131 (3) ◽

pp. 701-721 ◽

Cited By ~ 1

Author(s):

T Serikawa ◽

T Kuramoto ◽

P Hilbert ◽

M Mori ◽

J Yamada ◽

...

Keyword(s):

Genetic Map ◽

Coat Color ◽

Length Variation ◽

Data Bases ◽

The Public ◽

Gene Map ◽

Tandem Repeat Sequences ◽

Human Genes ◽

Public Data ◽

Inbred Rat

Abstract One hundred and seventy-four rat loci which contain short tandem repeat sequences were extracted from the GenBank or EMBL data bases and used to define primers for amplification by the polymerase chain reaction (PCR) of the microsatellite regions, creating PCR-formatted sequence-tagged microsatellite sites (STMSs). One hundred and thirty-four STMSs for 118 loci, including 6 randomly cloned STMSs, were characterized: (i) PCR-analyzed loci were assigned to specific chromosomes using a panel of rat x mouse somatic cell hybrid clones. (ii) Length variation of the STMSs among 8 inbred rat strains could be visualized at 85 of 107 loci examined (79.4%). (iii) A genetic map, integrating biochemical, coat color, mutant and restriction fragment length polymorphism loci, was constructed based on the segregation of 125 polymorphic markers in seven rat backcrosses and in two F2 crosses. Twenty four linkage groups were identified, all of which were assigned to a defined chromosome. As a reflection of the bias for coding sequences in the public data bases, the STMSs described herein are often associated with genes. Hence, the genetic map we report coincides with a gene map. The corresponding map locations of the homologous mouse and human genes are also listed for comparative mapping purposes.

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Near-Earth objects as principal impactors of the Earth: Physical properties and sources of origin

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307003304 ◽

2006 ◽

Vol 2 (S236) ◽

pp. 251-260

Author(s):

Dimitrij F. Lupishko ◽

Mario Di Martino ◽

Richard P. Binzel

Keyword(s):

Physical Properties ◽

Binary Systems ◽

Raw Materials ◽

Thermal Inertia ◽

Point Of View ◽

Main Belt ◽

Asteroid Hazard ◽

Axis Rotation ◽

Near Earth Objects ◽

Cometary Origin

AbstractNear-Earth objects (NEOs) are objects of a special interest from the point of view not only of cosmogonic problems of the Solar system, but of the applied problems as well (the problem of asteroid hazard, NEOs as the potential sources of raw materials, etc.). They are much smaller in sizes than main-belt asteroids (MBAs), very irregular in shape and covered with a great number of craters of different sizes. Most of NEOs are covered by regolith of low thermal inertia and different thickness. Objects with complex non-principal axis rotation (tumbling bodies) and with super-fast rotational periods have been detected among them. The new data, based on photometric and radar observations, evidence that about 15-20 %; of NEOs could be binary systems. Most of the classified NEOs fragments of differentiated assemblages of S-and Q-types. Analysis of physical properties of NEOs clearly indicates that the asteroid main-belt is the principal source of their origin and only about 10 % of NEOs have a cometary origin.

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Detection of Exomoons Inside the Habitable Zone

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313012751 ◽

2012 ◽

Vol 8 (S293) ◽

pp. 168-170

Author(s):

Luis Ricardo M. Tusnski ◽

Adriana Valio

Keyword(s):

The Other ◽

Planetary Orbit ◽

Habitable Zone ◽

The Moon ◽

Stellar Activity ◽

Orbital Parameters ◽

Hot Jupiters ◽

Habitable Zones ◽

Observational Bias ◽

Host Stars

AbstractSince the discovery of the first exoplanets, those most adequate for life to begin and evolve have been sought. Due to observational bias, however, most of the discovered planets so far are gas giants, precluding their habitability. However, if these hot Jupiters are located in the habitable zones of their host stars, and if rocky moons orbit them, then these moons may be habitable. In this work, we present a model for planetary transit simulation considering the presence of moons around a planet. The moon orbit is considered to be circular and coplanar with the planetary orbit. The other physical and orbital parameters of the star, planet, and moon, can be adjusted in each simulation. It is possible to simulate as many successive transits as desired. Since the presence of spots on the surface of the star may produce a signal similar to that of the presence of a moon, our model also allows for the inclusion of starspots. The goal is to determine the criteria for detectability of moons using photometry with the CoRoT and Kepler telescopes taking into account the stellar activity.

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Meteorite hazard model for a space mission to Mars

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012031 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012031

Author(s):

N Y Demina ◽

A O Andreev ◽

Y A Nefedyev

Keyword(s):

Spatial Distribution ◽

State Standard ◽

Complex Problem ◽

Space Mission ◽

The State ◽

Distribution Model ◽

Orbital Parameters ◽

Space Flights ◽

Near Earth Space ◽

The Earth

Abstract Currently, for the world’s space agencies, the robotic exploration of Mars is one of the most important tasks. One of the necessary stages for the implementation of this mission is the development and addition of new information to the State standard “Meteoric substance, spatial distribution model”. Until now, the State Standard has been more detailed in comparison with the American analogue (developed by NASA) and the European one. The standard is a mandatory document in the design of spacecraft. It should be noted that modeling of meteor hazard at a distance from Earth to Mars is a complex problem, since the analysis of the meteor population in near-Earth space does not give a complete picture of the propagation of meteoroids along the Earth-Mars route. Moreover, the further the trajectory of the spacecraft from the Earth’s orbit is, the less the number of near-Earth meteorites becomes. That is, objects that have the same orbital parameters with small bodies crossing the Earth’s orbit. The only way to solve this problem is to build an interpolation regression model, which is based on measurements from the Earth’s surface and observations of space missions. For this purpose, the density of sporadic meteoroids was transformed from the space mission coordinate system to the ground one. This was done in order to analyze meteorite observations by the Mariner 4 and Pioneer 10 spacecrafts. The results of the work made it possible to obtain new data for the spatial distribution of meteoroids on the Earth-Mars path. According to a comparison of our data with the data on the density of space debris in the previous works the most safe for space flights are normalization conditions of distributions of the elements of the orbits of meteoric bodies P(Z, e, i) < 60.

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Characteristics of small-sized space debris objects detected at the Terskol observatory in 2016-2017

Open Astronomy ◽

10.1515/astro-2018-0028 ◽

2018 ◽

Vol 27 (1) ◽

pp. 310-313 ◽

Cited By ~ 1

Author(s):

Polina Levkina ◽

Nail Bakhtigaraev ◽

Konstantin Martynyuk-Lototskyy ◽

Sergey Velichko ◽

Ilia Sokolov ◽

...

Keyword(s):

Space Debris ◽

Physical Characteristics ◽

Optical Instrument ◽

Earth Space ◽

Orbital Parameters ◽

Near Earth Space ◽

Optical Telescopes

Abstract The study of near-Earth space includes the detection and investigation of an increasing number of space debris objects by ground-based optical telescopes. There is no natural cleansing of space in the geostationary region. The telescope Zeiss-2000 with a two-meter aperture of the Terskol observatory is the largest optical instrument regularly used for space debris investigations. One of the main purposes in «Astronomy in the Elbrus region» international program’s boundaries is the detection and characterization of small fragments of debris,which are invisible for smaller telescopes. During observations on photometric nights we usually detect 4-5 unknown fragments of 17-21st star magnitude. In this article, we present orbital parameters and physical characteristics of several small-sized fragments of the space debris detected at the Terskol observatory in 2016-2017.

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Discussion: Regional Markets for Food and Interregional Competition: Implication for Southern Agriculture

Journal of Agricultural and Applied Economics ◽

10.1017/s0081305200024584 ◽

1981 ◽

Vol 13 (1) ◽

pp. 79-81

Author(s):

Lester H. Myers

Keyword(s):

Research Methodology ◽

Analytical Methods ◽

Data Bases ◽

Research Results ◽

Regional Markets ◽

Public Data ◽

Clear Delineation ◽

Return Home ◽

Data Requirements ◽

Comprehensive Discussion

A comprehensive discussion of research and interregional competition logically includes three major components: (1) a review of the overall need for the research results and a clear delineation of the differences in information requirements across types of clientele; (2) a description of the characteristics of the needed research methodology, as related to the specific clientele needs; and (3) the resulting data requirements, consistent with both the methodology and with the research objectives. Furthermore, in addressing a research-oriented audience, there should be emphasis on identifying “bottlenecks” that currently exist either in developed methodology or data bases, or both. Of course, the idealistic objectives are to stimulate the assembled audience, first, to return home with an enthusiasm for developing new and more appropriate analytical methods; and, second, to begin lobbying for better and more extensive public data resources.

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Near-Earth objects from the cometary flux

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314005092 ◽

2012 ◽

Vol 10 (H16) ◽

pp. 153-153

Author(s):

Vacheslav Emel'yanenko

Keyword(s):

Solar System ◽

Outer Solar System ◽

High Eccentricity ◽

Earth Space ◽

Near Earth Space ◽

Dynamical Characteristics ◽

Short Period ◽

Near Earth Objects

AbstractWe analyze the orbital distribution of objects captured to near-Earth space from the flux of comets coming from the outer Solar system. For this purpose, we use the model of the cometary cloud developed earlier (Emelfyanenko, Asher, Bailey, 2007). This model is consistent with the broad dynamical characteristics of observed near-parabolic comets, short-period comets, Centaurs and high-eccentricity trans-Neptunian objects. We show that the observed distributions of both large and small near-Earth objects are different from the modeled distribution formed dynamically by the action of planetary perturbations. In particular, while the distributions of arguments of perihelion for observed Jupiter-family comets and modeled cometary asteroids follow a sinusoidal law with pronounced maxima around 0 and 180 degrees, it is not the case for observed cometary asteroids of any size. We conclude that there exist many unobserved extinct short-period comets among near-Earth objects of various sizes.

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Observation of LEO Objects Using Optical Surveillance Facilities: The Geographic Aspect

Artificial Satellites ◽

10.2478/arsa-2019-0009 ◽

2019 ◽

Vol 54 (4) ◽

pp. 113-128

Author(s):

O.M. Kozhukhov ◽

T.O. Dementiev ◽

S.V. Rischenko ◽

N.I. Koshkin ◽

L.S. Shakun ◽

...

Keyword(s):

Geographic Location ◽

Simulation Modelling ◽

Low Earth Orbit ◽

Orbital Parameters ◽

Space Operations ◽

Near Earth Space ◽

The Us ◽

Space Objects ◽

Modelling Techniques ◽

Time Of Year

Abstract Simulation modelling of the observability of low Earth orbit (LEO) objects was performed using optical surveillance facilities depending on their geographic location and time of year. Orbital data for LEO objects from the open-access catalogue of the near-Earth space objects of the US Combined Space Operations Center (CSpOC) were taken as the initial data for the simulation. The simulation results revealed a complex relationship between the pattern of observability of a LEO object, its orbital parameters and location of the optical surveillance facility, in particular, for Sun-synchronous orbits (SSO) and observing facilities located near the equator. We also discuss variations in the frequency of passes of LEO objects into the field of view (FOV) and in the duration of their observation while passing through the FOV for optical surveillance facilities at three alternative locations. The obtained results and modelling techniques can be further used in the location planning of new optical observing facilities.

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