Washington, Sep 29: Solar observatory Sunrise, which was carried aloft by a NASA scientific balloon in early June 2013, has provided unique insights into a layer on the sun called the chromosphere.
Sunrise provided the highest-resolution images to date in ultraviolet light of this thin corrugated layer, which lies between the sun’s visible surface and the sun’s outer atmosphere, the corona.
With its one-meter mirror, Sunrise is the largest solar telescope to fly above the atmosphere. The telescope weighed in at almost 7,000 pounds and flew some 20 miles up in the air.
Sunrise was launched from Kiruna in the north of Sweden and, after five days drifting over the Atlantic, it landed on the remote Boothia Peninsula in northern Canada, gathering information about the chromosphere throughout its journey.
The temperature in the chromosphere rises from 6,000 K/10,340 F/5,272 C at the surface of the sun to about 20,000 K/ 35,540 F/19,730 C. It’s an area that’s constantly in motion, with different temperatures of hot material mixed over a range of heights, stretching from the sun’s surface to many thousands of miles up.
The temperatures continue to rise further into the corona and no one knows exactly what powers any of that heating.
Sunrise’s extremely high-resolution images in this wavelength painted a complex picture of the chromosphere. Where the sun is quiet and inactive, dark regions with a diameter of around 600 miles can be discerned surrounded by bright rims.
This pattern is created by the enormous flows of solar material rising up from within the sun, cooling off and sinking down again. Especially eye-catching are bright points that flash up occasionally-much richer in contrast in these ultraviolet images than have been seen before.
Scientists believe these bright points to be signs of what’s called magnetic flux tubes, which are the building blocks of the sun’s magnetic field. The magnetic field is of particular interest to scientists since it is ultimately responsible for all of the dynamic activity we see on our closest star. (ANI)