Explore planet Earth in near-real time!
Have you ever wanted to track natural events in progress, such as fires, floods and volcanic eruptions, or simply explore the planet through the eyes of a satellite? ESA has created a website, MIRAVI, which gives access to the most recently acquired images from the world’s largest Earth Observation satellite, Envisat.
MIRAVI tracks Envisat around the globe, generates images from the raw data collected by Envisat’s optical instrument, MERIS, and provides them online within two hours. MIRAVI is free and requires no registration.
To enjoy the service, simply visit the MIRAVI website - http://www.esa.int/miravi - and either browse the very latest images by clicking on the snapshots to the left, or view a specific location by either selecting an area on the world map or entering its geographic coordinates. MIRAVI also provides archived images since May 2006, searchable by date.
A virtually cloudless image of Madagascar
Although the images are fascinating and provide the marvellous feeling that users are ‘onboard the satellite’, they are not suitable for scientific use. Scientists use MERIS products that exploit the instrument’s 15 spectral bands and are generated with sophisticated algorithms. MIRAVI images use only a few spectral bands processed to appear the way the naked eye would see them.
Envisat circles the Earth in a polar orbit at an 800-km altitude, allowing MERIS to acquire global coverage every three days. MERIS measures the solar radiation reflected by the Earth, which means the sun must be present for MERIS to produce an image.
Last update: 9 April 2013
| ||MIRAVI (http://miravi.eo.esa.int/en/) |