1. Active Region 1002 on an Unusually Quiet Sun
... Astronomy Picture of the Day . Active Region 1002 on an Unusually Quiet Sun . << Yesterday . 24.09.2008 . Tomorrow >> . ... Our Sun has shown few active regions -- that house even fewer associated sunspots -- for over a year now, and such a period of ...
4. Multichannel Flare Spectrograph Archive 1997
... Date Time (UT) Counter Remarks _______________________________________________________________________________ 05.01. 10:29:17 2:06:42 scan disk 11:58:23 2:11:19 active regions 06.01. 09:49:51 2:12:17 scan disk 10:56:24 2:19:10 active regions 12.01. 09:39 ...
6. IDL-based Database of Solar Active Regions
... IDL-based Database of Solar Active Regions . Abstract: . 1 . Introduction . ... A database on solar active regions has been implemented in IDL (Interactive Data Language). ...
7. APOD: June 16, 1998 - An Active Region of the Sun
... June 16, 1998 . An Active Region of the Sun . Credit: A. Title ( Stanford Lockheed Institute ), TRACE , NASA . ... Explanation: The Sun is a busy place. This false-color image depicts an active region near an edge of the Sun . ...
9. http://hea-www.harvard.edu/AstroStat/Stat310_1011/ds_20110329.pdf
... 6 Using the cleaned images, sunspot active-region "seeds" are obtain by thresholding ... All pixels above this value are marked as belonging to the active-region. ... Left: Original Magnetogram Right: Active-region seeds 7 Using these seeds, we can ...