The wavelengths SDO observes and related images.

[Newbie]

From the sun's surface on out, the wavelengths SDO observes, measured in Angstroms, are:

4500: White light continuum, shows the sun's surface or photosphere

1700: Ultraviolet light continuum, shows surface of the sun. As well as a layer of the sun's atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising.

1600: Emitted by carbon-4 (C IV) at around 10,000 Kelvin. C IV at these temperatures is present in the upper photosphere and what's called the transition region, a region between the chromosphere and the upper most layer of the sun's atmosphere called the corona. The transition region is where the temperature rapidly rises. SDO images of this wavelength are typically colorized in dark yellow.

304: Emitted by helium-2 (He II) at around 50,000 Kelvin. This light is emitted from the chromosphere and transition region. SDO images of this wavelength are typically colorized in red.

171: Emitted by iron-9 (Fe IX) at around 600,000 Kelvin. This wavelength shows the quiet corona and coronal loops, and is typically colorized in gold.

193: Emitted by iron-12 (Fe XII) at 1,000,000 Kelvin and iron 24 (Fe XXIV) at 20,000,000 Kelvin. The former represents a slightly hotter region of the corona and the later represents the much hotter material of a solar flare. This wavelength is typically colorized in yellow.

211: Emitted by iron-14 (Fe XIV) at temperatures of 2,000,000 Kelvin. These images show hotter, magnetically active regions in the sun's corona and are typically colorized in purple.

335: Emitted by iron-16 (Fe XVI) at temperatures of 2,500,000 Kelvin. These images also show hotter, magnetically active regions in the corona, and are typically colorized in blue.

94: Emitted by iron-18 (Fe XVIII) at temperatures of 6,000,000 Kelvin. Temperatures like this represent regions of the corona during a solar flare. The images are typically colorized in green.

131: Emitted by iron-20 (Fe XX) and iron-23 (Fe XXIII) at temperatures greater than 10,000,000 Kelvin, representing the material in flares. The images are typically colorized in teal.

Courtesy SDO/ NASA et al

N.

Edited October 13, 2022 by Newbie

[hamateur 1953]

Bravo!  Good on ya!  waaaaay cool in yankee vernacular. 

1 hour ago, Newbie said:

From the sun's surface on out, the wavelengths SDO observes, measured in Angstroms, are:

4500: White light continuum, shows the sun's surface or photosphere

1700: Ultraviolet light continuum, shows surface of the sun. As well as a layer of the sun's atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising.

1600: Emitted by carbon-4 (C IV) at around 10,000 Kelvin. C IV at these temperatures is present in the upper photosphere and what's called the transition region, a region between the chromosphere and the upper most layer of the sun's atmosphere called the corona. The transition region is where the temperature rapidly rises. SDO images of this wavelength are typically colorized in dark yellow.

304: Emitted by helium-2 (He II) at around 50,000 Kelvin. This light is emitted from the chromosphere and transition region. SDO images of this wavelength are typically colorized in red.

171: Emitted by iron-9 (Fe IX) at around 600,000 Kelvin. This wavelength shows the quiet corona and coronal loops, and is typically colorized in gold.

193: Emitted by iron-12 (Fe XII) at 1,000,000 Kelvin and iron 24 (Fe XXIV) at 20,000,000 Kelvin. The former represents a slightly hotter region of the corona and the later represents the much hotter material of a solar flare. This wavelength is typically colorized in yellow.

211: Emitted by iron-14 (Fe XIV) at temperatures of 2,000,000 Kelvin. These images show hotter, magnetically active regions in the sun's corona and are typically colorized in purple.

335: Emitted by iron-16 (Fe XVI) at temperatures of 2,500,000 Kelvin. These images also show hotter, magnetically active regions in the corona, and are typically colorized in blue.

94: Emitted by iron-18 (Fe XVIII) at temperatures of 6,000,000 Kelvin. Temperatures like this represent regions of the corona during a solar flare. The images are typically colorized in green.

131: Emitted by iron-20 (Fe XX) and iron-23 (Fe XXIII) at temperatures greater than 10,000,000 Kelvin, representing the material in flares. The images are typically colorized in teal.

Courtesy SDO/ NASA et al

N.

 

[Sam Warfel]

Very nice. It would be helpful if you also listed what portion of the electromagnetic spectrum they are all in. Just yesterday I had to go through a tedious conversion from 171 Angstroms to nanometers and then look up that wavelength in the EM spectrum. Maybe not the best way, but I couldn’t find anywhere that said “these wavelengths from SDO are in the infrared” or whatever, which seems like a bit of an oversight 

[hamateur 1953]

There is a website convertlive.com   I find myself using this frequently. ( I am lazy) 🤣

[3gMike]

6 hours ago, Orneno said:

Very nice. It would be helpful if you also listed what portion of the electromagnetic spectrum they are all in. Just yesterday I had to go through a tedious conversion from 171 Angstroms to nanometers and then look up that wavelength in the EM spectrum. Maybe not the best way, but I couldn’t find anywhere that said “these wavelengths from SDO are in the infrared” or whatever, which seems like a bit of an oversight 

Converting Angstroms to nanometres is straightforward - just divide by ten.

So everything in the list is 450nm or less. Since SDO/NASA describe 4500 Angstrom (450nm) as white light continuum it seems they have a fairly broadband filter (white light comprises all colours from violet to red - nominally 400nm to 700nm).

1600 and 1700 Angstrom (160 and 170nm) are Near UV. All others are Extreme UV

[Newbie]

The solar spectrum (observable light) lies between approximately 390 - 660 nm (3900 - 6600 Angstroms). The spectral lines highlight specific emissions . A spectral line is like a fingerprint that can be used to identify the atoms, elements or molecules present in a star, galaxy or cloud of interstellar gas. A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range. Top diagram. 

The bottom diagram depicts the intensity of the spectral emissions from the sun, in Angstroms. Greatest intensity around 4000 A* 400nm.

N.

Edited October 14, 2022 by Newbie