Spicules comprise one of the most fundamental components of the solar chromosphere. They appear to be jets of gas seen at the limb of the Sun in chromospheric spectral lines, and have been observed in Hα and other chromospheric spectral lines for over 100 years. They have an upward mass flux 100 times that of the solar wind, and therefore are an important consideration in the mass balance of the solar atmosphere.
Source : NASA
It's estimated that there are around 3 million spicules on the Sun's surface at any given time. They tend to be several thousand kilometers long, and last for 15 minutes or so.
Since their discovery in the late 1800s, there have been many attempts at explaining their origin and structure. At present, there are at least six prominent theories - none of which has been generally accepted (see paper linked above).
Ideas for new topics, and suggested additions / corrections for old ones, are always welcome.
If you have skills or interests in a particular field, and have suggestions for Wikenigma, get in touch !
Or, if you'd like to become a regular contributor . . . request a login password. Registered users can edit the entire content of the site, and also create new pages.
( The 'Notes for contributors' section in the main menu has further information and guidelines etc.)
You are currently viewing an auto-translated version of Wikenigma
Please be aware that no automatic translation engines are 100% accurate, and so the auto-translated content will very probably feature errors and omissions.
Nevertheless, Wikenigma hopes that the translated content will help to attract a wider global audience.