mercredi 18 décembre 2013

Solar Dynamics Observatory Shows Sun's Rainbow of Wavelengths















NASA - Solar Dynamics Observatory (SDO) patch / NASA - ESA - SOHO Mission patch.

Dec. 18, 2013


This still image was taken from a new NASA movie of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, showing the wide range of wavelengths – invisible to the naked eye – that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors.

Jewel Box Sun

Video above: This movie, created by NASA's Scientific Visualization Studio at NASA's Goddard Space Flight Center in Greenbelt, Md., shows how features of the sun can appear dramatically different when viewed in different wavelengths. Image Credit: NASA's Goddard Space Flight Center.

Telescopes help distant objects appear bigger, but this is only one of their advantages. Telescopes can also collect light in ranges that our eyes alone cannot see, providing scientists ways of observing a whole host of material and processes that would otherwise be inaccessible.

A new NASA movie of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, shows the wide range of wavelengths – invisible to the naked eye – that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors.

As the colors sweep around the sun in the movie, viewers should note how different the same area of the sun appears. This happens because each wavelength of light represents solar material at specific temperatures. Different wavelengths convey information about different components of the sun's surface and atmosphere, so scientists use them to paint a full picture of our constantly changing and varying star.

Yellow light of 5800 Angstroms, for example, generally emanates from material of about 10,000 degrees F (5700 degrees C), which represents the surface of the sun. Extreme ultraviolet light of 94 Angstroms, which is typically colorized in green in SDO images, comes from atoms that are about 11 million degrees F (6,300,000 degrees C) and is a good wavelength for looking at solar flares, which can reach such high temperatures. By examining pictures of the sun in a variety of wavelengths – as is done not only by SDO, but also by NASA's Interface Region Imaging Spectrograph, NASA's Solar Terrestrial Relations Observatory and the European Space Agency/NASA Solar and Heliospheric Observatory (SOHO)-- scientists can track how particles and heat move through the sun's atmosphere.

Related Links:

Why scientists observe the sun in different wavelengths: http://1.usa.gov/1gvGGVn

About NASA’s heliosphysics fleet: http://www.nasa.gov/sunearth

To download the video in high resolution and various formats: http://svs.gsfc.nasa.gov/goto?11385

More information:

NASA Solar Dynamics Observatory (SDO): http://www.nasa.gov/mission_pages/sdo/main/

NASA SOHO Mission: http://www.nasa.gov/mission_pages/soho/#.UrHm6bS1udw

ESA SOHO Mission: http://sci.esa.int/soho/

Image, Video (mentioned), Text, Credits: NASA Goddard Space Flight Center / Karen C. Fox.

Greetings, Orbiter.ch