African Association of
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  • 12 Sep 2017 1:49 PM | Administrator (Administrator)


    Source: www.geospatialworld.net


    By: Amit Raj Signh



    What is LiDAR?


    Light Detection and Ranging.

    LiDAR is a remote sensing method that uses laser or light to measure the elevation like ground, forest and buildings.

    This means the LiDAR system sends a pulse of light and it waits for the pulse to return.

    It measures how long it takes for the emitted light to return back to the sensor. In the end, it gets a variable distance to the Earth. Read more...


  • 16 Jun 2017 8:59 PM | Administrator (Administrator)


    by S. Ramage for AWS



    The environment is measured with precision through Earth Observation (EO) satellite and in-situ – and the global community is leveraging this investment by accessing the information for free.


    The Global Earth Observation System of Systems (GEOSS), developed over the last decade, makes more than 200,000,000 open EO data resources accessible for better decisions on a range of areas from food security to protection of biodiversity, renewable energy and disaster resilience. With more than 150 data providers, an important element of GEOSS is a brokering framework called the GEO DAB (Discovery and Access Broker). 


    The GEO DAB makes use of cloud IaaS and PaaS AWS capabilities including load balancing, DNS routing, auto-scaling, monitoring, elastic map reduce, storage, and computing.

    Our changing planet is characterized every day by extreme weather events and increasing numbers of people vulnerable to the elements due to poor living conditions. With data becoming available in real time, wildfires can be identified and tracked and flooding can be predicted. Volcanoes and earthquakes have devastating consequences, but rescue missions can harness EO to speed up emergency response.


    Fossil fuel energy use accounts for more than two-thirds of greenhouse gas emissions and GEO is committed to increasing the global share of renewable energy sources, such as solar and wind power, in combination with energy efficiency, to help limit a further rise in global temperature. GEO’s energy community portal developed in partnership with MINES ParisTech supports many renewable energy related programmes, including the ones from the European Commission H2020 and Copernicus programmes, and the International Renewable Energy Agency (IRENA) Global Atlas for Renewable Energy project linked to the World Bank’s programmes for mapping renewable energy resources with EO data, ESMAP. Detailed information at high resolution that is broadly available allows improved cost estimates for governments or businesses looking to expand energy development.


    Deforestation and forest degradation are the second leading cause of global warming, responsible for about 15 percent of global greenhouse gas emissions. The process of photosynthesis in plants takes carbon dioxide out of the atmosphere, so there is a strong incentive to stop the destruction of forests. GEO’s Global Forest Observations Initiative (GFOI) is helping developing countries measure, report and verify forest areas and carbon stocks, critical not just for the Paris Agreement under the UN Framework Convention on Climate Change, also for the UN Agenda 2030.


    The GEOSS evolution includes big data analytics to move from data sharing to information and knowledge generation and sharing, in particular to support the UN Agenda 2030 and the Sustainable Development Goals (SDGs). GEO supports:

    • Sustainable Development Goal 2 (zero hunger) through its GEOGLAM crop monitors.
    • Goals 3 and 11 through activities for air quality.
    • Goal 6 on water through water quality analysis.
    • Goals 11 and 15 on land consumption and degradation by building developing better. approaches to generating Land Cover products.
    • Goals 14 and 15 on biodiversity and ecosystems by facilitating improved monitoring.
    • Above all, GEO is a global community and partnership and supports SDG Goal 17 of partnerships through its intergovernmental status.

    GEO convenes providers and users of open EO data, aiming to highlight best practices and eliminate duplication of effort to harness the Data Revolution for the benefit of humanity. With the support of commercial sector leaders, such as Amazon, this mission is advanced.


  • 07 Apr 2017 3:09 PM | AARSE Admin (Administrator)


    By Prof Moses Azong Cho


    Biodiversity conservation and management is a major concern in Africa where the increasing population of the continent is largely dependent on the dwindling natural resource base for their livelihood. The advent of new freely available satellite imageries such as Sentinel- 2 and Landsat-8 have offered new opportunities for biodiversity assessment and monitoring on the African continent. The improved spatial and spectral resolutions of these new satellites have also renewed demands for algorithm or methodological protocol development, particularly for African diverse landscapes. It is for the above reason that Prof Cho Moses, the African Association of Remote Sensing (AARSE) convener of the technical committee on algorithm development and application in collaboration with the Faculty of Geo-Information Science (ITC), University of Twente, The Netherlands organised a two-week refresher course on “Vegetation mapping and monitoring using Sentinel 2 data”, at the Council for Scientific and Industrial Research (CSIR), Pretoria, South Africa, 14-25 November 2016. Twenty participants from 10 different African countries including Ethiopia, Ghana, Kenya, Mozambique, Nigeria, South Africa, Sudan, Tanzania, Zambia and Zimbabwe, took part in the refresher course. The participants included remote sensing and GIS professionals working in the private and public sectors. The course programme included lectures on the importance of essential biodiversity variables, downloading and process of Sentinel-2 images, physically-based and empirical methods to retrieve essential biodiversity variables from Sentinel-2 images, MATLAB programming, practical field visit to measure essential biodiversity variables and practical exercises. In general, the refresher course provided an opportunity for learning, discussion, practical field experiments and exercises with Sentinel-2 images. The refresher course was facilitated by ITC (Dr. Roshanak Darvishzadeh,  Prof. Andrew Skidmore and Dr. Tiejun Wang) and CSIR  (Prof Cho Moses, Dr Abel Ramoelo) scientists. The refresher course was funded by NUFFIC through ITC and the CSIR.


  • 05 Mar 2017 11:16 PM | AARSE Admin (Administrator)


    Communiqué

    THE AFRICAN ASSOCIATION OF REMOTE SENSING COMPANIES

    IN THE COURSE OF CREATION

    On the sidelines of AARSE 11th Conference held in Kampala, Uganda, from 24 to 28 October 2016, members of Private African Companies of Remote Sensing,

    • -       considering that one of the major lessons learned from the survey carried out by AARSE on the African Remote sensing private sector is that it should create a Pan-African Association;
    • -          considering the urgent need to combine their efforts, skills and resources to create a Pan African Association of Remote Sensing Companies, under the auspices of AARSE;
    • -          considering the role that such an association can and should play in advancing the interests of the African Remote Sensing private sector across the continent for the benefit of all African stakeholders;
    • -          considering the historical role that the African remote sensing private sector can and must play in the sustainable socio-economic development of the continent;

    Read more


    French


  • 08 Dec 2016 12:08 PM | AARSE Admin (Administrator)



    AMMAN - The Arab States Research and Education Network (ASREN) has recently been approved as a Participating Organization for the Group on Earth Observations (GEO) – which includes Member governments of 102 nations, the European Commission, and 103 Participating Organizations (regional and international bodies with a commitment to advance Earth observations (EO)). GEO operates on a global partnership basis to leverage and co-ordinate EO activities to help tackle major global environmental challenges. ASREN will contribute towards GEO’s objectives by helping connect existing North African EO centers to the North African research and education networks, thus providing the e-Infrastructure essential for EO data acquisition, processing and distribution. ASREN will engage with the EO research community to assess and meet its data-communications needs and liaise with governments and other stakeholders in the Arab region.



    ASREN’s primary objective is to assist the implementation of GEO’s African regional initiative AfriGEOSS, which held its first Symposium last April at Victoria Falls and sets out to focus current GEO activities across Africa. AfriGEOSS aims to engage at governmental and scientific levels, and concentrate initially on strengthening EO for food security, and agriculture and sustainable forest management areas. ASREN will work closely with GÉANT - the pan-European research and education network, which is already a GEO Partner, and with WACREN in Western and Central Africa and the UbuntuNet Alliance in Eastern and Southern Africa, to harness their efforts to promote pan-African R&E networking through their AfricaConnect2 project to support the implementation of AfriGEOSS.

     

    H.E. Dr. Talal Abu-Ghazaleh, Chairman of ASREN said: “ASREN is now going beyond connectivity and service provision as we are now working with more global organizations such as Group on Earth Observations to promote collaboration and to enable joint research activities that can benefit from the e-Infrastructures we are establishing jointly with our partners, namely, the AfricaConenct2 Project”.

    Dr. Barbara J. Ryan, Secretariat Director said: “GEO welcomes ASREN into its global community as we envisage ASREN will advance GEO’s coordination with the scientific community, especially in a region that is not yet fully engaged in GEO.” She added, “As this decade of GEO calls for greater connection and support with global development issues, the work of the research networks in e-infrastructure will ensure better dissemination of information derived from Earth observations.”


    About Group on Earth Observations (GEO)


    GEO is a voluntary partnership of governments and organizations that envisions “a future wherein decisions and actions for the benefit of humankind are informed by coordinated, comprehensive and sustained Earth observations”. GEO membership includes 102 Member governments and 103 Participating Organizations comprised of international bodies with a mandate in Earth observations. The GEO community is creating a Global Earth Observation System of Systems (GEOSS) that will link Earth observation resources world-wide across multiple Societal Benefit Areas.


    About the Arab States Research and Education Network (ASREN)


    Arab States Research and Education Network (ASREN) is the association of the Arab region National Research and Education Networks (NRENs), that aims to implement, manage and extend sustainable Pan-Arab e-Infrastructures dedicated for the Research and Education communities, and to boost scientific research and cooperation in member countries through the provision of world-class e-Infrastructures and E-services.

     

    About AfricaConnect2


    AfricaConnect2 is an EU-funded pan-African connectivity project that aims to support the development and consolidation of high-capacity regional internet networks for R&E across Africa and their interconnection with the pan-European GÉANT network, creating a continental gateway for collaborative research and education across and beyond Africa.


    © ASREN 2015 | Powered by: Talal Abu-Ghazaleh Organization




  • 08 Dec 2016 12:01 PM | AARSE Admin (Administrator)

     

    This event was aimed at providing an opportunity to discuss issues of industry collaboration and support (such as training in EO business management, mentoring platform for African start-ups, partnerships, etc.). The creation of an African EO industry association was discussed. The association shall be formulated to be a sub-set to AARSE. Formal 20-minute match-making sessions took place between companies to network and foster collaboration. 


    Present at the B2B were the following companies:


    African companies


    http://www.africanremotesensing.org/resources/Archive/November%202016/AARSE%202016%20Afric%20companies%20descriptions.pdf


    European companies

    http://www.africanremotesensing.org/resources/Archive/November%202016/AARSE2016%20EU%20companies%20description.pdf

  • 08 Dec 2016 11:28 AM | AARSE Admin (Administrator)

    The 11th International Conference of the African Association of Remote Sensing of the Environment (AARSE) was held on 24 – 28 October 2016 in Kampala, Uganda. AARSE awarded Dr Phil Mjwara, Director General of the Department of Science and Technology of South Africa and CoChair of the Group on Earth Observations (GEO), with the AARSE Highest Award of Excellence. The award is in recognition of his foremost contribution to and support for the development on Earth Observations (EO) and geospatial information in Africa and in particular for the AfriGEOSS Initiative and increasing the visibility of Africa in GEO. “This award is an acknowledgement of the efforts of the AfriGEOSS community”, said Dr Mjwara, accepting the award. 


    Dr Mjwara on the right with Rt. Hon. Prime Minister of the Republic of Uganda, Dr. Ruhakana Rugunda and the AARSE President, Professor Jide Kufoniyi

    http://www.earthobservations.org/documents/afrigeoss/201611_mjwara_aarse_award.pdf

  • 17 Jul 2016 12:27 PM | AARSE Admin (Administrator)

    L.Ngcofe1, K. Gottschalk2, S.Madlanga3

    1Department of Rural Development and Land Reform, Chief Directorate: National

      Geo-Spatial Information, Mowbray.

    2 Department of Political Studies, University of the Western Cape, Cape Town

    3 National Research Foundation: Hartebeesthoek Radio Astronomy Observatory 

     

    Abstract 

    The costs of Africa being a late starter in space include the exponentially accumulating space debris. This threat to space assets is worse in low earth orbit (LEO), where it has already destroyed an Irridium operational US comsat.

    The current discussions in international forums about mitigating the creation of new space debris, has not yet gone to the next stage to discuss financial liability for collisions caused by such debris. Late starters in space need to table the responsibility of the historic space powers to seek ways to remove their cumulative debris from orbit, and finance this.


    Introduction

    The ability to observe the Earth from space has enhanced accurate-up-to-date environmental monitoring, thus overcoming some of the environmental challenges experienced by humankind. Investment in space activities has endless, long term, benefits including diplomatic relations; technological advancement through collaboration with other countries; improving overall economic activities in the global arena, which in turn vastly contributes towards addressing social ills. Acknowledging this Chung et al., (2010)  argues that where ground based systems are limited in frequency, continuity and coverage of important ecosystems, satellites can provide essential earth observation data on a continuous basis and over  a range of scales, from local, regional, to global. Access to and the development of space technology has historically been a key determinant of a country’s wealth, power, influence, status and prestige. However, space exploration has been an issue of marginal political interest in Africa, thus leading the continent to be the late starter in space matters. Sharpe (2010) shows Africa as the least active continent with regards to space exploration activities. Aganaba-Jeanty (2013) cites a lack of consistent funding as the greatest barrier of the African space technology development. He argues that according to 2009 to 2012 the countries within Africa represent the lowest spending countries in space exploration when compared to developed and developing countries. Africa as a late starter in space might be seen through Abiodun (2012) words of wisdom starting that “the quality and character of a man’s perceptions as well as his subsequent responses are determined in part by limitations imposed by or opportunities available in his environment. If he is to manifest any real growth and reach his higher potentials, his creativity would need nourishment from his environment”. Currently there are recent strides documented in literature showing Africa’s growing interest and participation in space exploration (Ngcofe et al., 2013; Abiodun, 2012; Wood & Wiegel, 2012; Gottschalk, 2010; Martinez, 2008; Mostert, 2008). It is of this view that this paper attempts to examine the impact of being a late starter on space exploration, particularly looking at the issue of space debris and its potential impact on Africa as a developing space fearing nation. 

     

    Space debris

    The current major threat of space exploration is the risk pertaining to space debris relative to the cost of launching satellites in space. The need to justify expenditure on space-related endeavours competes with other pressing expenditure needs such as provision of food, clean drinking water, housing, electricity, roads infrastructure and other commercial development. Space debris also known as orbital debris, or space junk, or space waste, is the collection of man-made objects that have exceeded its service life and broken down while in orbit around the earth (Interagency Report on Orbital Debris 2005; UN, 1999; Sénéchal, 2007; Colliot, 2002; Glassman, 2009; Griffiths, 2010). These include everything from spent rocket stages, old satellites, and fragments from disintegration erosion and collision. Space debris has vastly increased since the beginning of space travel in 1957 thus leading to orbit congestion (Colliot, 2012; Figure 2). According to NASA (2013), there are 500 000 pieces of debris tracked in orbit on Earth.

    Figure 1: Showing satellite and debris in Low Earth Orbit from 1960 to 2010 (NASA 2013). 

    Collision at orbital velocity can be extremely dangerous to functioning satellites and space manned missions. Sénéchal (2007) argues that at orbital velocity of more than 28000 km/h, an object as small as 1 cm in diameter has enough kinetic energy to produce significant impact damage, to partially or completely destruct an operational satellite. While an object of 1mm size can cause surface pitting and erosion, with larger objects of about 10 cm totally destroying operational satellites, and may even kill space explorers. According to the Kessler Syndrome space debris model, as the number of debris object increases, collisions become more likely to occur thus creating yet more debris (Griffiths, 2010; Colliot, 2012; Durrieu & Nelson, 2013). This is an immense concern, which threatens safety of future space explorations. Though space is a large environment, satellites are actually concentrated in a few orbits that are currently optimal, namely:

    • Low Earth Orbit (LEO) – this is the altitude from 160 km to 2000 km above the earth’s surface. LEO is largely used for earth monitoring, military surveillance, and communication satellites, especially around 350 km.
    • Medium Earth Orbit (MEO) – this is an area from 2000 km to 35 000 km and is mainly used by navigation satellites such as global position system (GPS) networks at around 20 000 km.
    • Geostationary Orbit (GEO) – this is the belt at 36 000 km and is optimal for communication satellites. However, Griffiths (2010) argues that it is more expensive to launch satellites to this orbit. Hence, many communication satellites are placed at LEO.
    • High Earth Orbit (HEO) – This is the area above 36 000 km, and used almost only by satellites researching the magnetosphere or other solar-terrestrial physics.

    LEO is regarded as the major used space orbit environment and therefore has a larger record of space debris than any other orbit. There has been four accidental collision events up-to-date (Durrieu and Nelson 2003), with a recent collision incident occurring in 2009 where a United States communication satellite collided with a defunct Russian satellite (Glassman, 2009; Griffiths, 2010; Smitham, 2010). These satellites collided at a speed of over 40 000 km/h, causing complete destruction of both satellites. Thus resulting in around 1400 recorded debris objects (Glassman, 2009; Griffiths, 2010; Smitham, 2010). The available computer models based on observation of debris used to predict future growth of the debris population and probability of collision with satellites under different assumptions reveal that in the next 40 years, collisions with objects larger than 10 cm in LEO are expected to occur on average every 5 years (Griffiths, 2010). This statistics coincide with Sénéchal (2007); Williamson (2003); Liou and Johnson (1996) who argued that in LEO the spatial density of objects is above critical point and the continuation of debris in this orbit may render it inaccessible in the future.

     

     

    Space availability

    The vulnerability of space asserts interference and disruption, led to the view, held by the USA security space community, that space is a contested domain. Whoever seizes space has a powerful advantage both for social and economic enhancement together with military applications (Sadeh, 2009). Space asserts provide a persistent view of the earth and offer ability of real or near real time global collection and dissemination of crucial information. Although, recently, there have been vast strides by Africa within the space arena, the continent still lags behind in space matters. Out of 53 countries in Africa, only four countries (Algeria, Egypt, Nigeria and South Africa) have successfully participated in space activities, through the development of their own space agencies which led to launching of their own satellites in space. The development of micro satellite technology and multiple constellations is now making space technology more affordable for developing countries to utilise the space environment (Durrieu & Nelson, 2013). Thus debate about the African Space Agency, which will cater for participation in space activities for Africa’s needs, is gaining momentum. Currently, Africa has an inspiring mission to the moon (http://africa2moon.developspacesa.org). With the vast interest in space activities by the African continent, one wonders, is there still space in space? Rex (1998) on his paper seeking to answer ‘will space run out of space’. He argues that there would be no major risk for space endeavours from current operational satellites only if it were not for space debris. The issue of space availability in space has been, and is still a major area of concern, more especially for Africa. Since the initial space exploration, the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPOUS) was established in 1959 in order to safeguard the use of space and promote space sustainability. This resulted in five UN treaties on Outer Space (http://www.oosa.unvienna.org/oosa/COPUOS/copuos.html) namely:

    1. Outer Space Treaty (1967) - This treaty promotes the international cooperation in the exploration and use of space, however, prohibits the usage of space for any nuclear weapons and / or any kind of weapons of mass destruction. It clearly emphasises that no state can claim sovereignty of or occupy outer space, the moon or any other Celestial Body. This treaty further deals with liability and states responsibility as to inform the UN  secretary general and the international scientific community of the nature, conduct, location and results of their activities in outer space.
    2. Rescue Agreement Treaty (1968) - This agreement deals with the rescue of astronauts, the return of astronauts and the return of objects launched into outer space. This agreement has a legal framework for emergency assistance of astronauts and the notification of launching of any space objects which has to return to earth and express who should be responsible for all the cost incurred for such a particular mission.
    3. Liability Convention (1972) - This convention is a pact of international liability for damage caused by space objects. It imposes an international and absolute liability on a launching state, or states as well as on those states who are members of inter-governmental organisations, for any damage caused by their objects. Launching state is defined as the state which launches or procures the launching of a space object or from whose territory or facility a space object is launched, irrespective of the success or not of the launch. Damage includes the loss of life, personal injury or any other impairment or health or loss of damage to property of state or of persons, natural or juridical or property of international, intergovernmental organisations. This also applies to any damage caused by a space object on the surface of the earth or to an aircraft flight.
    4. Registration Convention Treaty (1974) - The treaty obliges states to register all space objects in a register, which is maintained by the UN secretary general since 1962.
    5. Moon Treaty (1979) - The treaty declares that the moon is a global common for all humankind and is not subject to national appropriation and occupation.  It further stresses that no private ownership is allowed but all state parties have the right to exploration and use of the moon. In practice, this treaty has no force, because none of the space powers who engage in lunar exploration have ratified it: USA, Russia, China and India.

    Although, these treaties exist there has been non-compliance by those leading space faring countries. Since the 1960s, the United States and Russia have conducted dozens of anti-satellite (ASAT) test missions in space, which resulted in most of orbital debris experienced even today (Weeden, 2013). Most recently China has performed an ASAT mission against its aging FY-1C weather satellite at 855 km altitude on the 11/01/2007. It launched a missile, which destroyed the satellite, resulting in 3000 pieces of debris larger than 10 cm in size (Glassman, 2009; Weeden, 2013). This event was further followed by the United States ASAT in 21/02/2008, firing a missile that destroyed one of its military satellites at around 250 km altitude. The US ascertained that the satellite was uncontrollably descending into the atmosphere with nearly fully fuelled tank of toxic hydrazine. Furthermore, its altitude was low enough to ensure swift re-entry of all the resulting space debris, and so, harmless to the space environment. The US delegate fully briefed the UN COPUOS unlike the Chinese.  The outcome by the US in destroying its satellite is applaudable. However, ignorance has been shown by the former President George W. Bush when asked what would the people say about the mission? He said “I don’t care what people will say. We’re doing it for the right reason, and it’s transparent” (Oberg, 2008). These clearly are signs of bullying with regard to space matters by space powers with advanced space technologies.  

     

    Conclusion

    The act of destroying a satellite can damage the space environment by creating dangerous amounts of space debris. Space debris can, therefore, lead to collisions and loss of important satellites, which has tremendous cost effects for Africa’s participation in space activities. Losing a satellite in-orbit due to space debris is no longer hypothetical, but rather a harsh reality and is likely to increase with years to come (Smitham, 2010). Grego (2014) argues that deliberate space debris creation might result in conflict between space fearing nations with unpredictable and dangerous consequences. Such consequences might trigger an arms race which would further divert the economic and political resources from other pressing issues like food security, climate change, health issues, etc. The need to sustain benefits of space for present and future generations and other countries that have not explored space as yet is vital if we are to obtain continuous benefits from space activities. Glassman (2009) suggests that a number of activities and commitments need to be revitalised. Current space best practice, also termed rules of the road, seek to minimize causing new space debris, through careful revision of both design and operational protocols:

    • ·      Separation of satellites from their carrier rocket should no longer result in loose bolts and other metal pieces flying off;
    • ·      satellites should have some propulsion capability to initiate collision avoidance manoeuvres;
    • ·      at the end of their service life, satellites, especially those in geosynchronous orbit (GSO), should be manoeuvred into a “graveyard orbit” at a different altitude;
    • ·      and valves should open to discharge any remaining propellant, to prevent overheating and explosive disruptions.

    Technology debates about the most cost-effective ways of removing existing space debris range from laser vaporization of fragments, to ion-propelled robotic scavengers that would capture, and then de-orbit, dead satellites, in LEO. No international forum has yet resolved who should pay for this.

     

    Space situational awareness for Africa should not only focus on launching satellites in space but also embark on space debris tracking studies together with assessing and monitoring collision risk models. African satellite manufacturers need to consider whipple shields where needed. African members of COPUOS need to table debate on the financial responsibility of the historic space powers to remove their space debris, as this becomes technologically feasible. They should propose that payment for such space debris removal should be pro rata to the cumulative total of payloads each historic space power has orbited.

     

    References

    Abiodun AA. Trends in the global space arena – Impact on Africa and Africa’s response. Space Policy. 2012; 28: 283-290.

    Aganaba-Jeaty T. Precursor to an African space agency: Commentary on Dr Peter Martinez “Is there a need for an African Space Agency”. Space Policy. 2013; 29: 168-174.

    Anzaldua A., 2014. Orbital debris: resource ladder to the stars. The space review magazine.

    Chung SY, Ehrenfreund P, Rummel JD, Peter N. Synergies of Earth science and space exploration. Advances in Space Research. 2010; 45: 155-168.

    Colliot T., 2012. Space Risk: A new generation of challenges. An insurer’s perpective from Allianz Global Corporate and Speciality.

    Durrieu S., Nelson R.F., 2013. Earth observation from space – The issue of environmental sustainability. Space Policy, 29 (4): 238-250.

    Foust J., 2014. The quest for on-orbit authority. The space review magazine.

    Glassman A., 2009. The growing threat of space debris. IEEE, Today’s engineer magazine.

    Gottschalk K. South Africa’s space programme – Past, present, future. Astropolitics. 2010; 8(1): 35-48.

    Grego L., 2012. A history of anti-satellite programs. Union of Concerned Scientists, 1-6.

    Griffiths M., 2010. Space Debris. Postnote, 355: 1-4.

    Interagency Report on Orbital Debris, 1995. Office of Science and Technology Policy for the National and Technology Council Committee on Transportation Research and Development.

    Johnson N.L., 2001. Space debris modelling at NASA. Provided by the NASA Astrophysics Data System

    Lele A., 2014. Reaching Mars: is it about great power status. The space review magazine.

    Liou J.C., Johnson, N., 2006. Risk in space from orbiting debris. Science, 311.

    Martinez P. The 2nd African leadership conference on space science and technology for sustainable development. African Skies/Cieux Africans. 2008; 12: 2-11.

    Milligan T., 2014. Space ambition. The space review magazine.

    Mostert S. The African Resource Management (ARM) satellite constellation. African Skies/Cieux Africans. 2008; 12: 53-56.

    Ngcofe L, Gottschalk K. The growth of space science in African countries for Earth observation in the 21st century. South African Journal of Science. 2013; 109:1-5.

    Oberg J., 2008. US Satellite shootdown: The inside story. IEEE Spectrum. www.spectrum.ieee.org.

    Rex D., 1998. Will space run out of space? The orbital debris problem and its mitigation. Space Policy, 14: 95-105.

    Sadeh E., 2009. Space policy challenges facing Barack Obama administration. Space Policy, 25: 109-116.

    Sénéchal T., 2007. Orbital Debris: Drafting, negotiating, implementing a convention. Msc Thesis submitted to the MIT Sloan School of Management.

    Sharpe C. Space economic readiness – Economic analysis of public funding of space technology in developing African countries [dissertation]. Strasbourg: International Space University; 2010.

    Smitham M.C., 2010 The need for a global space traffic control service: an opportunity for US Leadership. Maxwell paper, 57: 153-170

    Taverney T., 2014. Protecting space capabilities from physical and fiscal threats. The space review magazine.

    United Nations 1999. Technical Report on Space Debris.

    Van Wyk JA., 2008. Overview of the implementation status of the five United Nations Treaties on Outer Space in African countries. African Skies/Cieux Africans, 12: 90-98.

    Weeden B., 2013. Anti-Satellite Tests in Space – The case of China. Secure World Foundation. www.swfound.org.

    Williamson M., 2003. Space ethics and protection of space environment. Space Policy, 19: 47-52.

    Wood D, Wiegel A. Charting the evolution of satellite programs in developing countries – The space technology ladder. Space Policy. 2012; 28: 15-24.

    NASA, 2013. Space Debris and Human Spacecraft

    http://www.nasa.gov/mission_pages/station/news/orbital_debris.html

    http://africa2moon.developspacesa.org/

    http://www.oosa.unvienna.org/oosa/COPUOS/copuos.html 
     


  • 17 Jul 2016 12:05 PM | AARSE Admin (Administrator)

    Source: African Archaeological Review


    This article discusses how archaeological sites in Sierra Leone, and by extension much of West Africa, can be identified through vegetation patterns (vegetation signatures) detectable in very high-resolution (VHR) multispectral satellite imagery. Settlement sites typically have a differing pattern of vegetation from the surrounding landscape, including concentrations of very large trees with sociocultural and historical significance: cotton (Ceiba pentandra) and baobab (Adansonia digitata). These features are conspicuous elements of the landscape both from the ground and in aerial imagery. Two complementary methods of using VHR multispectral satellite imagery are discussed in this paper: visual interpretation and semi-automated subpixel classification. These techniques are aiding ongoing archaeological survey of the Sierra Leone River Estuary. The impact of recently renewed industrial activity at a site of probable archaeological significance is also assessed through visually interpreted VHR satellite imagery.


    Full article

  • 17 Jul 2016 11:52 AM | AARSE Admin (Administrator)

    Source: Joint Research Centre


    Many areas in Ethiopia are currently facing water-related emergencies due to El Niño-induced drought, which has left 5.8 million people across the country without access to safe water. The JRC has provided satellite images of the worst affected districts so that UNICEF can locate deep water and organise drilling of wells. Otherwise, the affected communities have to rely on expensive commercial trucks to haul in water as rains are too limited to compensate and maintain sufficient water in the shallow groundwater wells.


    Groundwater (compared to rivers/lakes or other surface water) supplies 80 % of all drinking water in Ethiopia. The most sustainable groundwater is very deep. To locate it and then to drill and extract it is a major challenge. Information derived from different types of satellite images are important inputs along with geological data in the complex analysis undertaken by hydrologists to map areas of potential groundwater reservoirs and select appropriate sites for drilling.  So far, due to the cost of accessing and processing high-spatial resolution satellite imagery, limited groundwater investigation had been undertaken in this country. UNICEF was able to overcome this problem thanks to JRC support to process and analyse data from various satellite sensors over seven districts, mainly in Afar and Somali regions.




    Original article

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