scholarly journals Modern radar techniques and the hazard of meteoroids to space platforms

1998 ◽  
Vol 41 (5-6) ◽  
Author(s):  
G. Cevolani
Keyword(s):  
Parent Body ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Meteoroid Streams ◽  
Storm Activity ◽  
Plasma Generation ◽  
Near Earth Space ◽  
Space Objects ◽  
Very High ◽  
Perihelion Passage

Modern radar techniques, and in particular ground based radars, are a powerful tool to observe space objects (natural meteoroids and artificial space debris) on account of their all-weather and day-and-night performance. Natural meteoroids are an important component of the near-Earth space environment and represent a potential risk for all Earth-orbiting space platforms, which could significantly increase in coincidence of enhanced (outburst or storm) activity of meteoroid streams. A review of the currently active meteoroid streams suggests that a few streams have shown a quasi-periodic outburst activity in the two last centuries and may even undergo a storm activity in the next few years. The Leonids, the most intense of meteor showers, present a potentially serious damage to spacecraft in November of 1998 and 1999, after the perihelion passage of the parent body. Impact probability values of storm meteoroids on space platforms in Low Earth Orbit (LEO) were calculated using the data recorded during systematic observational campaigns carried out by the FS radar facility Bologna-Lecce in Italy. Meteoroid flux predictions and directionality, and investigation on impact parameters at very high velocities (up to 71 km/s) for penetration, charge production and plasma generation, are relevant aspects to develop strategies for safe deployment of the near Earrth-orbiting space platforms.

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

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.

scholarly journals MONITORING THE ARTIFICIAL SPACE OBJECTS WITH UKRAINIAN NETWORK OF OPTICAL STATIONS

2021 ◽  
Vol 34 ◽  
pp. 85-92
Author(s):  
Ya.O. Romanyuk ◽  
O.V. Shulga ◽  
L.S. Shakun ◽  
M.I. Koshkin ◽  
Ye.B. Vovchyk ◽  
...  
Keyword(s):  
Low Earth Orbit ◽  
Satellite Observations ◽  
Earth Orbit ◽  
Short List ◽  
Geostationary Earth Orbit ◽  
Earth Space ◽  
Near Earth Space ◽  
Space Objects ◽  
Successes And Challenges

The article describes the successes and challenges of the Ukrainian network of optical stations (UMOS) in recent years in the field of astrometric observations of artificial space objects both in low-Earth orbit (LEO) and geostationary Earth orbit (GEO). UMOS was established in 2012 as a joint partnership of organizations interested in satellite observations for scientific purposes and practical near Earth space monitoring. The main purpose of the UMOS has been (and still is) to combine scientific and technical means with regular optical (positional and / or non-positional) observation. The short list of equipment of the UMOS members are given in the tables. The programs for observations, used methods and obtained results are described in the paper. In conclusion, the advantages of observations of artificial space objects by means of a network are summarized. The experience of UMOS and main results obtained by UMOS can be considered as the first step to create the SSA system of Ukraine.

scholarly journals The Interaction between the LEO Satellite Constellation and the Space Debris Environment

2021 ◽  
Vol 11 (20) ◽  
pp. 9490
Author(s):  
Shuyi Ren ◽  
Xiaohua Yang ◽  
Ronglan Wang ◽  
Siqing Liu ◽  
Xiaojing Sun
Keyword(s):  
Growth Rate ◽  
Success Rate ◽  
Space Debris ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Risk Level ◽  
Collision Risk ◽  
Orbital Parameters ◽  
Space Objects ◽  
The Impact

The wide application of satellite constellations in the field of space-based global communications and remote sensing has led to a substantial increase in small-satellite launch plans, a sharp increase in the density of space objects in low-Earth orbit (LEO), and a reduction in available orbit and frequency resources. This will further aggravate the trend of deterioration of the space debris environment. Taking the Starlink constellation as an example, this paper describes the influence of the constellation from the environmental debris flux of the satellite, the evaluation of the number of evasion maneuvers, the change of risk level, the success rate of post mission disposal (PMD) and the growth rate of space objects. The simulation results show that the collision risk of the Starlink constellation is related to the orbital parameters, and the higher success rate of post-mission disposal (PMD) can reduce the collision risk of the constellation. The large constellations increases the growth rate of space objects, and even if all the satellites are disposed of after the mission, the impact of constellations on the space environment can not be offset.

Evalution of technical means capabilities for minimisation of technogenic pollution of a near space

2015 ◽  
Vol 26 (3-4) ◽  
pp. 124-131
Author(s):  
N. M. Dron ◽  
P. G. Horolsky ◽  
L. G. Dubovik
Keyword(s):  
Space Debris ◽  
Outer Space ◽  
Ecological Condition ◽  
Space Environment ◽  
Launch Vehicles ◽  
Earth Space ◽  
Near Earth Space ◽  
Near Space ◽  
Space Objects ◽  
Major Factors

The conducted researches are directed on the solution of one of the most important problems of the space use – a problem connected with existence and inadmissibility of growth the quantity of a technogenic origin space debris on low near-earth and geostationary orbits because its further increase will overlap to mankind an exit in space and will terminate space activity. In the basis of a technique of researches the analysis of an existing ecological condition of the surrounding space environment on which base determined the major factors of pollution of the space and considered ways of struggle against space debris on near-earth orbits is put. It is established that the major factors of pollution of the near-earth space are spent stages of launch vehicles and accelerating units, the space crafts which have terminated its existence, fragments of destroyed artificial space objects, operational elements etc. Space debris basically is concentrated on low orbits and around a geostationary orbit which on the basis of the analysis of statistical data on space crafts starts are in most common use. Here groupings of space crafts of the various particular mission, including space crafts of communication, relay, TV, the early prevention of a rocket attack are concentrated. It is shown that the main ways of struggle against space debris are prevention of occurrence new and removal of the already existing debris. Notable decrease in level of the pollution can achieve at cumulative use of such measures, as an exception of explosions of the space objects, limitation of quantity of the started space crafts, reduction of number of the accompanying fragments injected into orbits at starts. Methods and means of withdrawal from working orbits of space crafts upon termination of term of their active existence and known ways and systems of active removal of already existing fragments of the space debris, such as: application of an ionic bunch, the space ship-towing vehicle, the polyurethane foam, the pulsing laser, harpoon system, electrodynamic cord system are considered. Scientific novelty of the presented results consists in the description of conceptual actions for reduction of pollution of the space. The activities executed in the given direction, have huge practical value as the outer space exploration gives huge advantage and significant progress to mankind, but the further operation at near-earth space by existing methods without acceptance of the measures indicated in the article, its further safe development already will not allow in the near future.

Observing Earth space environment with LEO multi-mission data

2021 ◽  
Author(s):  
Claudia Stolle ◽  
Chao Xiong ◽  
Ingo Michaelis
Keyword(s):  
Attitude Control ◽  
Temporal Variations ◽  
Low Earth Orbit ◽  
Added Value ◽  
Space Environment ◽  
Electron Content ◽  
Data Sets ◽  
Earth Space ◽  
Near Earth Space ◽  
In Situ Data

<p>In situ data from satellites in Low Earth Orbit (LEO) has become indispensable to monitor and explore near-Earth space. In contrast to ground-based observations they provide global coverage, and they sense parameters at altitudes that often remain hidden when applying remote sensing techniques either ground- or space-based. </p><p>In recent years, data derived from instruments onboard LEO missions, which were not primarily dedicated for space science application, have proven added value in deriving the spatial and temporal variations of the magnetosphere, ionosphere and thermosphere.</p><p>This presentation will discuss the benefit of calibrated data from platform magnetometers that are originally designed for spacecraft attitude control. We will put focus on the dual-satellite GRACE-FO mission, that is suitable to derive scale-lengths, e.g., for auroral field-aligned currents, and in constellation with data from other platform magnetometers to resolve the local time dependence of the magnetospheric ring current signal. We further introduce new data sets of electron density and GPS-derived topside electron content from the GRACE and GRACE-FO missions.</p>

scholarly journals The Effect of Low Earth Orbit Atomic Oxygen Exposure on Phenylphosphine Oxide-Containing Polymers

2000 ◽  
Vol 12 (1) ◽  
pp. 43-52 ◽  
Author(s):  
John W Connell
Keyword(s):  
Thin Film ◽  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Earth Orbit ◽  
Cooperative Effort ◽  
Flight Experiment ◽  
Oxygen Exposure ◽  
Atomic Oxygen Exposure ◽  
Phenylphosphine Oxide

Thin films of phenylphosphine oxide-containing polymers were exposed to low Earth orbit aboard a space shuttle flight (STS-85) as part of flight experiment designated Evaluation of Space Environment and Effects on Materials (ESEM). This flight experiment was a cooperative effort between the NASA Langley Research Center (LaRC) and the National Space Development Agency of Japan (NASDA). The thin-film samples described herein were part of an atomic oxygen exposure (AOE) experiment and were exposed to primarily atomic oxygen (∼1×1019 atoms cm−2). The thin-film samples consisted of three phosphine oxide-containing polymers (arylene ether, benzimidazole and imide). Based on post-flight analyses using atomic force microscopy, x-ray photo-electron spectroscopy and weight loss data, it was found that the exposure of these materials to atomic oxygen (AO) produces a phosphorus oxide layer on the surface of the samples. Earlier work has shown that this layer provides a barrier towards further attack by AO. Consequently, these materials do not exhibit linear erosion rates which is in contrast with most organic polymers. Qualitatively, the results obtained from these analyses compare favourably with those obtained from samples exposed to AO and/or an oxygen plasma in ground-based exposure experiments. The results of the low Earth orbit AO exposure on these materials will be compared with those of ground-based exposure to AO.

scholarly journals The affect of the space environment on the survival ofHalorubrum chaoviatorandSynechococcus(Nägeli): data from the Space Experiment OSMO on EXPOSE-R

2014 ◽  
Vol 14 (1) ◽  
pp. 123-128 ◽  
Author(s):  
R. L. Mancinelli
Keyword(s):  
Survival Rate ◽  
Uv Radiation ◽  
Molecular Probes ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Dust Particles ◽  
Most Probable Number ◽  
Earth Orbit ◽  
Probable Number ◽  
Space Vacuum

AbstractWe have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate ofSynechococcus(Nägeli), a halophilic cyanobacterium isolated from the evaporitic gypsum–halite crusts that form along the marine intertidal, andHalorubrum chaoviatora member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms exceptBacillusspores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (λ > 110 nm or λ > 200 nm, cosmic radiation (dosage range 225–320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live–Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 ± 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live–Dead stain suggested ~10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life beyond earth, the potential for interplanetary transfer of viable microbes via meteorites and dust particles as well as spacecraft, and the physiology of halophiles.

scholarly journals The Ad Hoc Back-End of the BIRALET Radar to Measure Slant-Range and Doppler Shift of Resident Space Objects

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 577
Author(s):  
Luca Schirru ◽  
Tonino Pisanu ◽  
Angelo Podda
Keyword(s):  
Doppler Shift ◽  
Space Debris ◽  
Ad Hoc ◽  
Low Earth Orbit ◽  
Slant Range ◽  
Radar Systems ◽  
The Earth ◽  
Space Objects ◽  
Resident Space Objects ◽  
Potential Issue

Space debris is a term for all human-made objects orbiting the Earth or reentering the atmosphere. The population of space debris is continuously growing and it represents a potential issue for active satellites and spacecraft. New collisions and fragmentation could exponentially increase the amount of debris and so the level of risk represented by these objects. The principal technique used for the debris monitoring, in the Low Earth Orbit (LEO) between 200 km and 2000 km of altitude, is based on radar systems. The BIRALET system represents one of the main Italian radars involved in resident space objects observations. It is a bi-static radar, which operates in the P-band at 410–415 MHz, that uses the Sardinia Radio Telescope as receiver. In this paper, a detailed description of the new ad hoc back-end developed for the BIRALET radar, with the aim to perform slant-range and Doppler shift measurements, is presented. The new system was successfully tested in several validation measurement campaigns, the results of which are reported and discussed.

Could future COP talks help to de-junk near-earth space?

Soundings ◽  
2021 ◽  
Vol 78 (78) ◽  
pp. 81-85
Author(s):  
Susmita Mohanty
Keyword(s):  
Space Debris ◽  
Outer Space ◽  
Low Earth Orbit ◽  
Observation Data ◽  
Earth Space ◽  
Near Earth Space ◽  
Earth Environment ◽  
Outer Space Treaty ◽  
Earth Observation Data ◽  
Earth’S Climate

Space debris has reached alarming proportions and is growing at a frightening pace, because of the expanding number of satellites circulating in Low Earth Orbit (LEO), designed to increase global Internet coverage and provide earth observation data. LEO satellites are now being launched in mega-constellations, including by Elon Musk's company SpaceX. It is time to completely overhaul the 1967 Outer Space Treaty, which was not designed to deal with current problems. The COP forum should therefore include the near-earth environment within its concept of the earth's climate, enabling the UN to acknowledge, as a collective, the growing menace of human-made debris in near-earth space, and, in partnership with the UN-Outer Space Affairs Office (UN-OOSA), call for a new declaration on LEO.

Sign in / Sign up

Export Citation Format

Share Document