Satellite Experience

Brief: We know that satellites exist above us but knowledge of how they work and where exactly they are at any time is more elusive. This project involves revealing some of these hidden aspects of satellite technology and thinking about how we can configure the considerable technical power of satellite technologies for social good.

What is satellite？

https://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-a-satellite-58.html

What are satellites used for？

https://www.ucsusa.org/resources/what-are-satellites-used

• Military satellites -- mostly for reconnaissance, defense and intelligence. 
• Commercial satellites -- for communication, entertainment-related purposes, mapping and more.
• GPS satellites -- for supporting navigations systems.
• Scientific satellites -- for biological research programs, health care, climate studies, space research, evaluating agricultural patterns, weather and more.

As a rule of thumb, the lower an image resolution is, the better the image quality. Click on the links below to see simulation satellite images at multiple resolutions of the same object:

• 50 cm resolution: This is the most common resolution used in Google Maps. The image is pixelated.
• 25 cm resolution: This is the best publicly available resolution for satellites. The image slightly less pixelated, but the details are still indiscernible.
• 5 cm resolution: This is the resolution known within the limits of spy satellites, according to tech expert Nooria Khan. The image comes into focus. You can make out two men sitting at a bus stop, wet spots from melted snow, a trash can and defined shadows on the sidewalk.
• 1 cm resolution: Experts believe that this resolution is used by advanced government spy satellites. You can see clothing details, cracks in the sidewalk and small bits of trash on the ground.

Satellite remote sensing of wetlands

“To conserve and manage wetland resources, it is important to inventory and monitor wetlands and their adjacent uplands. Satellite remote sensing has several advantages for monitoring wetland resources, especially for large geographic areas. Early work with satellite imagery used visual interpretation for classification. The most commonly used computer classification method to map wetlands is unsupervised classification or clustering. Maximum likelihood is the most common supervised classification method. Wetland classification is difficult because of spectral confusion with other landcover classes and among different types of wetlands. However, multi-temporal data usually improves the classification of wetlands, as does ancillary data such as soil data, elevation or topography data. Classified satellite imagery and maps derived from aerial photography have been compared with the conclusion that they offer different but complimentary information. Change detection studies have taken advantage of the repeat coverage and archival data available with satellite remote sensing. Detailed wetland maps can be updated using satellite imagery.

Ozesmi, S.L. and Bauer, M.E., 2002. Satellite remote sensing of wetlands. Wetlands ecology and management, 10(5), pp.381-402.

Different types of wetlands studied using reflectance (Butera 1983). The optimum time for

satellite remote sensing detecting mangroves was considered to be late summer to early fall, when the vegetation was mature and Satellite remote sensing has been used to study all cloud cover was less frequent than in the winter. Generally the easiest wetland Bogs and fens, or northern peatlands, have also classes to detect are permanently flooded or intermit- been mapped with satellite remote sensing (Franklin tently exposed open water ponds (palustrine uncon- et al. (1994), Gluck et al. (1996) (fens); Palylyk et al.

Space-based geodetic measurements of the solid Earth with the Global Positioning System

Space-based geodetic measurements of the solid Earth with the Global Positioning System, for example,combined with ground-based seismological measurements, are yielding the principal data for modeling lithospheric processes and for accurately estimating the distribution of potentially damaging strong ground motions which is critical for earthquake engineering applications. Moreover, integrated with interferometric synthetic aperture radar, these measurements provide spatially continuous observations of deformation with sub-centimeter accuracy. Seismic and in situ monitoring, geodetic measurements, high-resolution digital elevation models (e.g. from InSAR, Lidar and digital photogrammetry) and imaging spectroscopy (e.g. using ASTER, MODIS and Hyperion) are contributing significantly to volcanic hazard risk assessment, with the potential to aid land use planning in developing countries where the impact of volcanic hazards to populations and lifelines is continually increasing. Remotely sensed data play an integral role in reconstructing the recent history of the land surface and in predicting hazards due to flood and landslide events. Satellite data are addressing diverse observational requirements that are imposed by the need for surface, subsurface and hydrologic characterization, including the delineation of flood and landslide zones for risk assessments. Short- and long-term sea-level change and the impact of ocean-atmosphere processes on the coastal land environment, through flooding, erosion and storm surge for example, define further requirements for hazard monitoring and mitigation planning.

Tralli, D.M., Blom, R.G., Zlotnicki, V., Donnellan, A. and Evans, D.L., 2005. Satellite remote sensing of earthquake, volcano, flood, landslide and coastal inundation hazards. ISPRS Journal of Photogrammetry and Remote Sensing, 59(4), pp.185-198.

Satellite And culture Impact

Inuit wayfinding and orienting methods have received the attention of ethnographers, explorers, and popular writers, attracted by the fact that Inuit usually travel across extensive and sometimes indistinct territories without using maps or instruments. Inuit orient themselves on the land by understanding wind behaviour, snowdrift patterns, animal behaviour, tidal cycles, currents, and astronomical phenomena (MacDonald 1998). Inuit way- finding methods are burdensome to learn, requiring years of quiet tutoring and experience, but are perfectly reliable. Despite the power, allure, and rapid distribution of GPS technology worldwide, few people have examined its social and cultural implications.

The typical Inuit’s knowledge of geographic and environmental surroundings is impressive. Some Inuit are familiar with thousands of kilometres of trails and remember uncountable landmarks and details of the land. Since the Inuit approach to geography is mainly oral, specific locations are identified by positioning them in reference to landmarks seen on the horizon through the use of wind bearings.Travelers going to well-known hunting and fishing destinations and to other communities frequently follow routes that have been used from time immemorial.

As we have seen, most hunters create their waypoints on location instead of entering the coordinates manually. If circumstances prompted them to use their receivers, they would navigate not by coordinates but just by following the direction indicated by the GPS arrow. In March 2001, during a meeting of the Inullariit Elders Association in which Aporta presented some of the results of his research, the elders attending spontaneously started a discussion of the GPS, unanimously expressing their admiration for the navigational instrument and their worries about its potential effects on younger generations. Their main concerns were that a GPS receiver can break and it would be wrong to rely on an instrument that breaks, that some of the knowledge and skills they had learned from older generations would get lost as younger people came to rely more on GPS technology, and that inexperienced hunters using GPS units might fall into thin ice or go by very inefficient routes just to follow the straight course suggested.

Alianakuluk (2002), an elder who is not a GPS user himself, expressed a very critical position:

As for myself I regret the fact that they are abandoning their Inukness, the vast knowledge that Inuit hold is just being put in the back burner; it is for this I regret the fact that knowledge is going to be lost. Of course people are free to do as they wish. The wisdom and knowledge of the Inuit are being diminished with these gadgets. It is too, too bad.

The central questions that must be asked of GPS and, indeed, of all technology is how it can respect engagement—the direct relationship that exists when people such as Inuit hunters are aware of and prepared for the continuity, fragility, complexity, and difficulty of living close to the environment. Failure to address such questions, we believe, leads to the erosion of social integrity and understanding of the significance of the places that support us. Indeed, our incapacity and inexperience in dealing with the moral and material consequences of new technology have created a hazardous laissez-faire approach.

Aporta, C., Higgs, E., Hakken, D., Palmer, L., Palmer, M., Rundstrom, R., Pfaffenberger, B., Wenzel, G., Widlok, T., Aporta, C. and Higgs, E., 2005. Satellite culture: global positioning systems, Inuit wayfinding, and the need for a new account of technology. Current anthropology, 46(5), pp.729-753. 

The Economic rationales of 5G

For example, providing coverage in rural or remote areas has been challenging in many countries because the investment cost may not justify the expected revenue. In contrast, a single communication satellite can cover a large geographic area, and thus it might be economically appealing to use satellite communications to augment terrestrial networks to provide connectivity in rural and remote areas. In urban areas, high-throughput satellites communications systems may help offload traffic in terrestrial networks.

The large satellite coverage can also benefit communication scenarios with airborne and maritime platforms (onboard aircrafts or vessels), while being attractive in certain machinetomachine and telemetry applications. Additionally, satellites are resilient to natural disasters on earth, making satellite communications key for emergency services in case that the terrestrial network infrastructures are degraded. Service continuity is closely related to ubiquitous connectivity. When a user equipment (UE) enters an unserved or underserved area, the connectivity service may be disrupted. Integrating satellite communications into terrestrial networks to fill the coverage holes can enable smoother service continuity.

Zhang, J., Zhang, X., Imran, M.A., Evans, B., Zhang, Y. and Wang, W., 2017. Energy efficient hybrid satellite terrestrial 5G networks with software defined features. Journal of Communications and Networks, 19(2), pp.147-161.

Scared of the satellize--Privacy

Satellite and analytics companies say they’re careful to anonymize their data, scrubbing it of identifying characteristics. But even if satellites aren’t recognizing faces, those images combined with other data streams—GPS, security cameras, social-media posts—could pose a threat to privacy. “People’s movements, what kinds of shops do you go to, where do your kids go to school, what kind of religious institutions do you visit, what are your social patterns,” says Peter Martinez, of the Secure World Foundation. “All of these kinds of questions could in principle be interrogated, should someone be interested.”

Like all tools, satellite imagery is subject to misuse. Its apparent objectivity can lead to false conclusions, as when the George W. Bush administration used it to make the case that Saddam Hussein was stockpiling chemical weapons in Iraq. Attempts to protect privacy can also backfire: in 2018, a Russian mapping firm blurred out the sites of sensitive military operations in Turkey and Israel—inadvertently revealing their existence, and prompting web users to locate the sites on other open-source maps.

Capturing satellite imagery with good intentions can have unintended consequences too. In 2012, as conflict raged on the border between Sudan and South Sudan, the Harvard-based Satellite Sentinel Project released an image that showed a construction crew building a tank-capable road leading toward an area occupied by the Sudanese People’s Liberation Army. The idea was to warn citizens about the approaching tanks so they could evacuate. But the SPLA saw the images too, and within 36 hours it attacked the road crew (which turned out to consist of Chinese civilians hired by the Sudanese government), killed some of them, and kidnapped the rest. As an activist, one’s instinct is often to release more information, says Nathaniel Raymond, a human rights expert who led the Sentinel project. But he’s learned that you have to take into account who else might be watching.

Bullis, K., 2006. MIT Technology Review. Recuperado el, 20.

Satellite and educational scenario

The research evaluated the true benefits of GIS in secondary education and concluded that GIS can bring positive effect on students’ spatial thinking abilities only if two critical factors are met [9]: Firstly, teaching for understanding: Understand the geographic phenomena and / or sciences behind the complex GIS operations. Secondly, ability to extend what is learned in one context to other contexts: Apply the skills to another scope of study.

“performing advanced spatial analysis” to “the freedom of integrating facts of any perspectives spatially” and “enabling spatial thinking such that students can explore spatial patterns and relationships among those perspectives.” Hence, GIS should mainly act as a platform integrating knowledge and facts of various subjects, provide simple tools to practice spatial thinking skills and study the inter-relations among the collected facts, combine the observations with taught knowledge and explain / draw conclusion for the study accordingly. The essential roles of GIS include data integration, identification spatial patterns and relations among co-located facts among various perspectives, data visualization.

Example 1: 3D Visualizations and What-if Analysis.

The first and most powerful function of the geospatial data platform is visualizing and exploring geospatial data in three dimensions. Teachers and students can freely explore the “location”, “conditions” and “connections” among spatial features easily. This function also provides an interesting interactive learning environment as well as strong visual impacts of the analysis to the spatial thinkers. For example, there is a place called Tai O in Lantau Island which is a flooding black spot of Hong Kong. Students are asked to explain the reasons behind the frequent flooding in Tai O. With the three dimensional visualizations, students can quickly describe Tai O locates in the West of Lantau Island and is surrounded by mountains in all directions (i.e. location).