EROS Images
USGS/EROS Image Gallery
Cancun
USGS/EROS Image Gallery
Volga River Delta
USGS/EROS Image Gallery
West Fjords
USGS/EROS Image Gallery
Parana River Delta

Visualization Results of Global Download Requests

for EROS Satellite Images





Jump to: Motivation, Example Log File, To Use Webportal, Acknowledgment

Motivation

The motivation of this project is to develop a tool to visually analyze the massive global download requests for the satellite images maintained by the Earth Resources Observation and Science (EROS) Center of U.S. Geological Survey (USGS).  In September 2008, EROS annouced its new policy to place all of their satellite imagery in the public domain for free download. Since then, a large amount of spatial data contained in satellite images is generated every day and massive number of satellite data download requests have subsequently been processed. Up to Mar. 2011, more than one million requests have been processed and the volume of these requests is expected to increase steadily. However, this data is not well utilized by currently available data visualization tools. Therefore, this webportal has been designed to visualize the properties of global download requests for the satellite images and analyze the hidden download patterns.  This webportal provides easy access to this data that can be viewed as top results, downloaded .kml files to be viewed with Google Earth, or viewing the results in the browser using the Google Earth plug-in. Go to the Links section on this page to find where to download these scenes from EROS.

Example Log File

Below is a small sample of the log file that is created when a download request is made. This file contains a lot of valuable data, but it is not easy to see the most requested scenes. This file includes scene requested, satellite number, row and path of the satellite, date the scene was taken, and sensor time.

PRODUCT_REQUEST_ID   LANDSAT_SCENE   WRS_PATH    WRS_ROW     ACQ_DATE        SENS TIME_SENT_TO_LPGS
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
9990809260001_00723      LE70360382005196EDC00       36                     38                   07/15/2005    ETM  01-OCT-2008 00:02:17
9990809260001_00721      LE70280302005220EDC00       28                     30                   08/08/2005    ETM  01-OCT-2008 00:02:17
9990809260001_00722      LE70290382005291EDC00       29                     38                   10/18/2005    ETM  01-OCT-2008 00:10:43
9990809260001_00724      LE70300322005250EDC00       30                     32                   09/07/2005    ETM  01-OCT-2008 00:10:43
9990809260001_00726      LE70440272005284EDC00       44                     27                   10/11/2005    ETM  01-OCT-2008 00:12:24
9990809260001_00725      LE70280292005188EDC00       28                     29                   07/07/2005    ETM  01-OCT-2008 00:14:27
0800809300295_00001      LE71670642000189EDC00      167                    64                   07/07/2000    ETM  01-OCT-2008 00:20:34
9990809260001_00727      LE70150352005225EDC00       15                     35                   08/13/2005    ETM  01-OCT-2008 00:26:36
0800809300296_00001      LE71400192007243PFS00       140                   19                   08/31/2007    ETM  01-OCT-2008 00:26:36

To make the visualization, this data is loaded into a database by a system administrator using an Admin GUI.  Once the log file is added into the database users of this webportal can query the database to create .kml files that can be viewed with Google Earth or the the Google Earth plug-in.


To Use the Webportal

Custom Query

To make a query of the download requests navigate to the "Generate Visualization Results" tab on the top of this page. When at the Query page select the desired requirements. Once the desired choices are made, select Submit Query. This will bring up a download page that will display useful statistical results with the option to download .kml files or to view the results with the Google Earth plug-in.

Sample Query Result

Here is an example of a custom user query:

The row and path numbers relate to the global mapping scheme used by EROS to designate geographic locations relative to the position of the Landsat satellites that record the images. Every row/path combination maps to a unique Latitude/Longitude centered position on the earth.

Google Earth Plug-in

The results of the user-defined query can be viewed within the web browser by selecting the "View via Google Earth Plug-in" button at the bottom of the query results page. This currently only works for Windows users, and a download link for the browser plug-in will be provided if necessary. WARNING: Use of the browser plug-in is very graphics intensive and will result in sluggish response on machines with marginal graphics resources.

Pre-generated Visualization Data

A table of pre-generated KML files is accessible from a table by selecting the "Pre-Generated Visualization Results" button at the top of any page on the site. The table is organized by year and month, and the number of download requests for each month are displayed above each link. Several months display "No Data" because download requests for months prior to October 2008 (the release of satellite imagery to the public domain) were not analyzed, and data is not yet available for the later months.

Acknowledgment

We greatly appreciate the generous support from the Computer and Network Systems (CNS) Program of the National Science Foundation (NSF) under the Grants No. 0915762 and 1212535 as well as the Nelson Research Grant. We are also thankful to EROS for providing the global download requests data.

Links to download satellite images:


USGS/EROS Homepage
USGS Global Visualization Viewer - Website to Download Scenes from EROS
EarthExplorer