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Live Satellite Imagery – How To See Satellite Images Of Earth Online

What Is Live Satellite Imagery

Since the first satellite images ever were created back in 1946, this high-tech form of documenting the Earth has provided a unique perspective to scientists and ordinary people alike. Satellite imagery is used in a wide variety of applications to help create visual data which can be used to document, analyze and navigate the entire planet.

The main providers of satellite imagery tools and systems are:

  • GeoEye
  • DigitalGlobe
  • Spot Image
  • RapidEye
  • ImageSat International

Each company has their own satellites which collect data independently. This data is then shared and used among a variety of companies which create maps, annotations and other overlays to help make sense of the imagery and provide visual information.

How It Works

As you might imagine, satellite imagery works by collecting visual information through sensors mounted to a satellite orbiting in space. The sensors view just a small portion of the Earth at a time. The area being observed is known as a pixel. Each pixel represents a single area being viewed by a satellite.

Viewing satellite images through an online interface - screenshot

Interface of an online satellite imagery app

A pixel could be an area as small as 5 meters or as large as a kilometer. The smaller the pixel size is, the more detail a satellite is able to see. Each pixel may be recorded using multiple sensors such as one for blue light, one for red light and one for green light. Other sensors may be used for other bands such as infrared as well.

As satellites orbit the Earth data is read from the various sensors. Some satellites use mirrors which scan back and forth to record information. Others have long bars of sensors which can read in many different pixels of information at the same time. Either way, the satellite must process large amounts of information which is constantly being read by the various sensors as it moves across the sky.

Satellite Imagery Bands

Most satellites have sensors that record more than just colors. The most common satellite imagery bands are:

  • Blue-Green
  • Green (Sometimes mapped to Blue)
  • Red (Sometimes mapped to Green)
  • Near IR (Sometimes mapped to Red)
  • Mid-IR
  • Thermal IR
  • Short Wave IR
  • Panchromatic

As you can see, satellite imagery is much more than just taking a digital picture from a satellite. Most satellites include bands which help detect other frequencies of light which can be used for more detailed images and applications such as thermal IR.

Satellite Imagery Types

The most common types of satellite imagery include:

  • 2D Satellite Imagery – This is the most common type of satellite imagery. This includes your basic “flat” maps.
  • 3D Satellite Imagery – 3D imagery takes satellite images to another level. 3D imagery allows you to view elevation and other important details.
  • Thermal Satellite Imagery – Thermal imagery is mainly used for tracking weather patterns. It can also be used to locate volcanoes, wildfires and even industrial hot spots.