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The active regions on the Sun are rotating back into view, and appear to still be capable of producing strong flares and CMEs.
That's sunspot group 484 back for another round.

Below is the Sun at a wavelength of 284 Angstroms (extreme UV light). Looks like that area is still busy!

Compare that with the following image at 171 Angstroms (extreme UV):


1 posted on 11/13/2003 9:59:27 PM PST by petuniasevan
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To: MozartLover; Joan912; NovemberCharlie; snowfox; Dawgsquat; Vigilantcitizen; theDentist; ...

2 posted on 11/13/2003 10:06:40 PM PST by petuniasevan (!drawkcab ni deggulp draobyek ym tog ev'I kniht I)
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To: petuniasevan
Saturn Covers a Star
By Roger W. Sinnott

The 8.4-magnitude star follows this apparent track behind Saturn, as seen from anywhere on Earth, but the time it will reach a particular ring or gap could vary up to 10 minutes or so, depending on your location. (Remember to subtract 5 hours from UT for EST, 8 hours for PST.) Sky & Telescope illustration by Steven Simpson.
 
 
Late Friday night, November 14–15, Saturn and its ring system glide right in front of an 8.4-magnitude star in Gemini. Observers with large enough telescopes — ideally 8-inch or larger — can watch as the star leisurely fades in and out of view behind the various rings, gaps, and the open space between the rings and the ball of Saturn itself.

Skywatchers with the best view of this rare event are those living in western North America. They’ll be able to see the star enter the ring system Friday evening and finally leave it 7 hours later.

For eastern North America and most of South America, Saturn is higher in the sky during the initial stages; the star should reach the Cassini Division in the rings shortly before 1 a.m. Eastern Standard Time. These viewers can see the star coast right up to the planet’s limb around 2 a.m. EST, but dawn will prevent them from seeing it come out the other side.

European observers are limited to watching the star just enter the ring system as morning twilight interferes.

Sky & Telescope contributing editor Thomas A. Dobbins notes that two British amateurs witnessed a similar occultation of a 7th-magnitude star in 1917. Using 5-inch and 9-inch telescopes, they could dimly see the star behind the outer ring (ring A), making that ring seem translucent. But they failed to see the star when it was behind the brighter B ring.

Titan Too!

Just one day before it encounters Saturn this week, the same 8.4-magnitude star will be occulted by Titan, Saturn’s largest moon. Bruno Sicardy (Paris Observatory) describes this event on his Web site and points out that it may produce a “central flash” around 0:13 Universal Time on November 14th. Most likely to be seen from parts of South Africa, and lasting up to 10 seconds, the flash is a visible focusing of the star’s light by Titan’s atmosphere.


orange.gifAn Occultation Primer
orange.gifAn Observing Guide to Saturn

5 posted on 11/13/2003 11:50:56 PM PST by WSGilcrest (brrrrrrrr)
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To: petuniasevan
Love those Jupiter pics! BTTT
7 posted on 11/14/2003 4:54:49 AM PST by GodBlessRonaldReagan (where is Count Petofi when we need him most?)
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To: petuniasevan
I am now absolutely convinced that large sunspots create clouds over my viewing area.

Wow, I can not believe that 484 and 486 have returned once again. The next two weeks will be interesting to watch.

8 posted on 11/14/2003 11:13:29 AM PST by Hunble
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