Created by: Nishit K Patel (University of Illinois Urbana-Champaign)
CS498: Data Visualization Project
This visualization follows a hybrid structure that contains the several scenes. It is based on Interactive slideshow technique. In each slide, directions and guidance are provided which user can use to move between the slides at any time.
The project consists of few slides that contains interactive visualizations to convey the message. User can interact with these visualization to see the details of the data elements. Each visualization is followed by addition details in order to put additional light on the chart and data. These scenes were created using Reveal.js library which provides smooth transition between scenes, maintains coherency and provides rich user experience. The visual elements such as colors, fonts and apperance is consistent throuhout the project.
Annotations in this project are represented by tooltips which displays the details of the data points user is interested in. for example, in first stacked bar chart user can see the satellite type, usage and purpose etc. and on the other visualizations, displays Operator country, Apogee and Perigee etc. These annotations will appers when user will hover on data elements. In zoomable circle pack chart, user will see once they zoom into appropriate circles.
There are several parameter used throughout the project and in different form. There are two directonal arrows on each slides to navigate between the slides. User can also use mouse rollers or left and right keys from keyboard to navigate. The Arrow in the right direction will always appear to be active and left arrow will not but user can still use left arrow to navigate to previous scenes/slides. At the bottom of the page, users can also see the progress bar as well as current slide number.
All the charts in this projects have trigeers. For the first visualization user can filter the visual by clicking on data labels of the chart. This filters the stacked bar chart and shows only data points which user has selected. By clicking on same label again, user can go back to reset mode and can see full data in the chart. In second visualization, user can click on circles to zoom and see detail level data. Third visualization also has clickable legend to filter the data points on scatter plot.
The dataset used for this visualization is from Union of Concerned Scientst database. This dataset consists of data about all the satellites that orbit the earth today. Assembled by experts at the Union of Concerned Scientists (UCS), the Satellite Database is a listing of the more than 1,700 operational satellites currently in orbit around Earth. The database contains 26 types of data for each satellite, including technical information about each satellite (mass, power, launch date, expected lifetime) and its orbit (apogee, perigee, inclination, and period), as well as information on what the satellite is used for, and who owns, operates, and built the satellite.
The Stacked bar chart in the previous screen shows the satellites currently orbiting the earth and its age. These satellites are broken out by its usage type. Note that these are the satellites that are currently orbiting the earth and functioning. You can use chart legends to filter the data. This visual reveals some interesting information on how we have made progress throughout the years. For example it can be seen from visual that oldest functioning satellite that is still orbiting the Earth was launched 44 years ago for mix use of Military and Commercial purpose. Many of these old satellites were used for either military or commercial purposes.
Another observation which is somewhat obvious is the increase in number of satellites launched in recent years. We can see that since the beginning of the century there are constant increase in satellites launched year over year. Majority of these satellites appeares to be used for commercial and military purpose but we see an increase in other purposes as well.
These satellites serve specific purpose and orbit in its unique class. Some of the satellites have its fixed orbit type and orbit class i.e. how far it is orbiting from the earth, how the path of orbit look like etc. In the next screen let's take a look where these satellites are grouped by its purpose and then again by orbit type and its class.
Last chart illustrates what these satellites are used for. Satellites are shown in packed circle and first grouped by its purpose. We can see that some of the important areas in which satellites are used for are Communications, Earth Observation like weather prediction, navigation, space observation, space sciences etc. Satellites are then grouped by its orbit type, these includes but not limited to equatorial, sun-synchronus, polar, non-polar inclined and there are some satellites that do not have fixed orbit type and can be manuevered as needed. These satellites falls under none category as shown in the chart.
Satellites are further classified into third group which is its orbit class. There are LEO,GEO, MEO and elliptical. LEO is short for low earth orbit. These satellites orbit between 160 and 2,000 km above earth. MEO is short for medium earth orbit and altitude is between 2,000 and 35,786km. GEO stands for geosynchronous, or geostationary earth orbit and these satellites for higher than 35,786 km above earth's surface. You can zoom on this just by clicking on circles. Similarly you can zoom out by clicking anywhere on circle.
In the next slide, we will see how the Apogee and Perigee of these satellites compares which will give some understanding of how these satellites orbit and what purpose they are used for. Apogee and Perigee are helpful to calculate and identify the orbit type of a satellite. So lets take a look...
In last chart we see how apogee and perigee are compared for all satellites. Apogee and Perigee are terms which describe aspects of an elliptical orbit of satellites. Apogee is the distance when a satellite is at farthest from the Earth and Perigee is the distance when a satellite is at the closest distance from the Earth. These satellites are classified by the purpose it is used for so user can easily distinguish about a particular type of satellite by clicking on label signs. This Chart gives us good understanding of how satellites orbits around the Earth and how its path will look like.
Majority of the the satellites have Apogee less than 50,000 km and perigee less than 5,000 km and this is why many satellites data points are concentrated around the origin in the chart. Another observation from the chart is satellites used for Space Science have very high apogee and perigee which makes sense as these satellites scan larger portion of the solar system and universe for exploration. Satellites used for communications and navigation also have higher apogee and perigee compares to satellites used for earth observation. Users can use the legend to filter the data points. In the next screen, let's see how the world has made progess and what coutries have there satellites orbiting the earth...
In the above image, we can see that since the first satellite was launched back in 60's there were only few countries that had satellites let alone the capabilities of launcing the satellite with space launch. User can slide the bar to left or right to compare world between 1966 and 2016. In last 4 decades we have seen tremendous growth not only in number of satellies launched by several coutries but also in what purpose these satellites are used for. As of 2016, countries from virtually every continent have their satellite orbiting the earth. We also see the increase in coutries who have space launching capabilities as well.