by APOD Robot » Mon Jun 29, 2015 4:11 am
Sunspot Group AR 2339 Crosses the Sun
Explanation: How do sunspots evolve? Large dark
sunspots -- and the active regions that contain them -- may last for weeks, but all during that time they are constantly changing. Such variations were particularly apparent a few weeks ago as the active region
AR 2339 came around the limb of the Sun and was tracked for the next 12 days by NASA's
Solar Dynamic Observatory. In the
featured time lapse video, some sunspots drift apart, while others merge. All the while, the dark central
umbral regions shift internally and their surrounding lighter penumbras shimmer and wave. The surrounding
Sun appears to flicker as the carpet of yellow
granules come and go on the time scale of hours. In general,
sunspots are relatively cool regions where the local
magnetic field pokes through the Sun's surface and inhibits heating. Over the past week, an even more active region --
AR 2371 -- has been crossing the Sun and releasing powerful flares that have resulted in
impressive auroras here on Earth.
[/b]
[url=http://apod.nasa.gov/apod/ap150629.html][img]http://apod.nasa.gov/apod/calendar/S_150629.jpg[/img] [size=150]Sunspot Group AR 2339 Crosses the Sun[/size][/url]
[b] Explanation: [/b] How do sunspots evolve? Large dark [url=http://apod.nasa.gov/apod/ap050216.html]sunspot[/url]s -- and the active regions that contain them -- may last for weeks, but all during that time they are constantly changing. Such variations were particularly apparent a few weeks ago as the active region [url=http://earthsky.org/todays-image/large-sunspot-group-ar-2339]AR 2339[/url] came around the limb of the Sun and was tracked for the next 12 days by NASA's [url=http://sdo.gsfc.nasa.gov/mission/]Solar Dynamic Observatory[/url]. In the [url=https://www.youtube.com/watch?v=BejRxZAa66E]featured time lapse video[/url], some sunspots drift apart, while others merge. All the while, the dark central [url=http://www.spaceweatherlive.com/en/help/what-are-sunspots]umbral regions[/url] shift internally and their surrounding lighter penumbras shimmer and wave. The surrounding [url=http://missionscience.nasa.gov/sun/]Sun[/url] appears to flicker as the carpet of yellow [url=http://apod.nasa.gov/apod/ap111106.html]granules come and go[/url] on the time scale of hours. In general, [url=https://en.wikipedia.org/wiki/Sunspot]sunspots[/url] are relatively cool regions where the local [url=http://solarscience.msfc.nasa.gov/the_key.shtml]magnetic field[/url] pokes through the Sun's surface and inhibits heating. Over the past week, an even more active region -- [url=http://spaceweather.com/archive.php?view=1&day=23&month=06&year=2015]AR 2371[/url] -- has been crossing the Sun and releasing powerful flares that have resulted in [url=http://spaceweathergallery.com/aurora_gallery.html]impressive auroras[/url] here on Earth.
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