Our Beautiful Star

Wow this is a really beautiful picture of our closest star which is a G2V Class yellow dwarf, just in case you were interested (click on the picture to get a larger view) – Deskarati

This picture was taken by Alan Friedman using a filter that lets through only a very narrow wavelength of light emitted by hydrogen (called Hα for those of you keeping track at home), so this tracks the activity of gas on the solar surface. He also inverts the image of the solar disk (makes it a negative) to increase contrast. Somehow this adds a three-dimensional quality to the picture, and reveals an amazing amount of texture.

The scene-stealer is that detached prominence off to the left. That’s the leftover material ejected from the Sun by an erupting sunspot (you can see other sunspots in the picture as well). The gas is ionized — a plasma — and so it’s affected by magnetic fields. The material follows the magnetic field of the Sun in the explosion, lifting it off the surface and into space. Sometimes it falls back, and sometimes it leaves the Sun entirely. In this case, Alan caught some of the material at what looks like the top of its trajectory.

The beauty of this picture belies its violence and sheer magnitude: the mass of material in a prominence can easily top 10 billion tons! As for size, see that dark elongated sunspot near the base of the prominence, just to the right of the bigger, speckly one? That spot is roughly twice the size of the Earth.

Edited from badastronomy

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3 Responses to Our Beautiful Star

  1. Steve B says:

    H-alpha (Hα) emission is a red visible spectral line created by hydrogen with a wavelength of 656.28 nm. This emission occurs when a hydrogen electron falls from its third to second lowest energy level. If you want to find out more about this have a look at the Wikipedia page for the “Balmer Series”.

    • alfy says:

      Why all the publicity for Balmer, Steve? What about poor old Lyman, Bracket, Pashen and Pfund? If you are going to use a firm of central European solicitors, give credit where credit is due.

  2. Deskarati says:

    Thanks Steve, I feel a new post coming on!

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