EarthNow! Landsat Image Viewer
This page explains how to use the EarthNow! Landsat Image Viewer and describes how it provides information to you. For general questions about Landsat data or EarthNow!, please consult the frequently asked questions page.
EarthNow! displays data received from the Landsat 7 satellite. When a Landsat satellite passes within range of the ground station at the USGS Center for Earth Resources Observation and Science (EROS), image data are down linked and displayed in near-real time. When no satellites are within range, the most recent pass is displayed.
EarthNow! may be used by educators, scientists, or anyone with an interest in satellite imagery and the ways that satellite images show us changes in the Earth's surface. EarthNow! displays data from Landsat 7 Enhanced Thematic Mapper Plus (ETM+).
The EarthNow! applet is shown below. Its three sections are the moving window display, the satellite location display, and the information area. Click one of the sections for more information.
The moving window display shows image data for the current pass as it is received. Use the scroll bar to move up or down the display.
During live capture or playback of a pass, the satellite location display indicates the location of the satellite providing the data.
Red Line = Indicates the ground track of the satellite.
Red Box = Shows the area covered by the pass.
Blinking Yellow Line = Indicates the current location of the satellite.
Satellite Dish = Displays the location of the receiving station.
Shortly before a new live capture event is to begin the satellite location map will reflect the location of the approaching satellite. The image below shows the Landsat 7 satellite approaching the New England states from the province of Quebec.
The information area provides information about the current pass.
Information about the current pass is provided below the location display. This area shows the satellite that provided the data, whether the pass is live or being replayed, and the time of acquisition.
When a pass is being replayed, the next pass satellite and a countdown to when it will start is shown below the current pass information.