Credit NASA Goddard Space Flight Center Image by Reto Stöckli (land surface, shallow water, clouds). Enhancements by Robert Simmon (ocean color, compositing, 3D globes, animation). Data and technical support: MODIS Land Group; MODIS Science Data Support Team; MODIS Atmosphere Group; MODIS Ocean Group Additional data: USGS EROS Data Center (topography); USGS Terrestrial Remote Sensing Flagstaff Field Center (Antarctica); Defense Meteorological Satellite Program (city lights).
This spectacular “blue marble” image is the most detailed true-color image of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. These images are freely available to educators, scientists, museums, and the public. This record includes preview images and links to full resolution versions up to 21,600 pixels across.
Much of the information contained in this image came from a single remote-sensing device-NASA’s Moderate Resolution Imaging Spectroradiometer, or MODIS. Flying over 700 km above the Earth onboard the Terra satellite, MODIS provides an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth. The land and coastal ocean portions of these images are based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the sensor’s view of the surface on any single day. Two different types of ocean data were used in these images: shallow water true color data, and global ocean color (or chlorophyll) data. Topographic shading is based on the GTOPO 30 elevation dataset compiled by the U.S. Geological Survey’s EROS Data Center. MODIS observations of polar sea ice were combined with observations of Antarctica made by the National Oceanic and Atmospheric Administration’s AVHRR sensor—the Advanced Very High Resolution Radiometer. The cloud image is a composite of two days of imagery collected in visible light wavelengths and a third day of thermal infra-red imagery over the poles. Global city lights, derived from 9 months of observations from the Defense Meteorological Satellite Program, are superimposed on a darkened land surface map.Metadata
Visualization Date 2002-02-08
. All Sensors MODIS
. All Satellites Terra MODIS
. All Categories Collections Blue Marble Blue Marble 2002
Earth rotates on its slanting axis at an astonishing 1100 miles per hour. The and clouds move along with it and still we aren’t able to detect a single disturbance that might indicate that we are traveling at such a hair-raising speed all the time. So why can’t we able to sense this supersonic speed? Here is why:
Detecting movement and being aware of movement requires that we see something from a fixed point that theoretically doesn’t move while we are at it. From here, we can see the moving body with our eyes and feel the movement. For example, when we are on a bike and the world seems zooming past us very near us which gives us the feeling of movement. The bike, in this case, is stationary for us, but the world is moving around it. But, in the case of airplanes when we are moving at such high speeds at a particular height, the Earth seems to become stationary and only when we concentrate on individual objects on the ground very hard, we realize that we are moving.
When we are on Earth, everything around us is moving at exactly the same speed like us in the rotation so all visible Earth, in this case, is our frame of reference which is perceived to be stationary along with all the atmosphere. The only thing we can see to be conscious of our movement is the sky. The Sun, the moon, and the stars provide a true realization of our movement, but we still can’t feel a thing because of the slow angular motion of our planet with respect to them. If we could see them at this rate, now that would feel our movement:
But we can’t feel it because this whole process takes an entire night to complete. The stars too seem stationary, and so does the moon. Due to all these factors, we can’t appreciate the enormous speed with which the Earth moves around its axis.