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1 posted on 08/11/2004 11:57:44 AM PDT by lainie
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To: lainie
Thanks for the reminder...

This is great to watch!

2 posted on 08/11/2004 12:00:37 PM PDT by Kate of Spice Island ('Effin the ineffible since '91." FirstIAmAUSSoldier and I approve of this message...)
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To: lainie

Thanks, im going to check it out.


3 posted on 08/11/2004 12:01:03 PM PDT by No Blue States
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To: lainie

Mmm...hopes the weather clears. We have clouds and t-storms in MA.


4 posted on 08/11/2004 12:02:53 PM PDT by Gefreiter ("Flee...into the peace and safety of a new dark age" Lovecraft)
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To: lainie

Thanks,
To bad Eastern IA is forcasted to be cloudy.


5 posted on 08/11/2004 12:14:56 PM PDT by redgolum
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To: Howlin

Oh oh........

I think a LONG and LATE nap is in order for me today.


6 posted on 08/11/2004 12:15:56 PM PDT by Brad’s Gramma (If only hamsters could vote.......)
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To: lainie
Sky and Telescope
2004: An Excellent Year for the Perseids

"...The meteoroids of the Perseid stream range in size from pebbles to sand grains and have a consistency like bits of ash. They ram into our upper atmosphere at a speed of 60 kilometers per second, creating incandescent trails of shocked, ionized air as they vaporize."

"On the peak night, the Perseids will appear to diverge from a patch of sky between Perseus and Cassiopeia just east of the famous Double Cluster. The meteors’ apparent divergence from this radiant point is an effect of perspective; the meteoroids are actually traveling in parallel through space. Meteors appearing near the radiant will display short trails because we see them nearly end on, while those far from the radiant, seen broadside, look much longer.

"In the early-evening hours the radiant is low in the north-northeast, so the meteors strike the upper atmosphere at a low angle — and therefore we see comparatively few of them per square kilometer at the atmosphere’s top. As the night advances, the radiant rises higher in the northeast, the meteors arrive more nearly straight down, and so we see more of them. By the time morning twilight begins, the radiant has climbed to around 60° altitude for observers at midnorthern latitudes.

"If it’s cloudy on the peak night, don’t despair; for one or two nights before and after, rates are still roughly a quarter to half of the maximum. In fact, the first few forerunners of the shower may show up as early as July 20th; the last stragglers have been recorded as late as August 24th.

"Interference by moonlight this year will be minor, especially after the peak date, permitting night-after-night monitoring of the shower’s buildup and decline. On the morning of August 10th the thick waning crescent Moon won’t rise until about 1 a.m. local daylight time for observers in midnorthern latitudes. On the 12th, a thinner crescent will come up about 2:30 a.m. The Moon is new on the 15th, and for a week afterward the waxing crescent will set before midnight.

"...The direction to watch is wherever your sky is darkest, usually straight up."

"...because recent perturbations by Jupiter are directing old Perseid meteoroids about 0.01 a.u. closer to the Sun, the core of the broader, "traditional" stream may be shifted closer to Earth's orbit, resulting in a stronger-than-average annual shower. In fact, Lyytinen and Van Flandern suspect that the Perseids tend to put on stronger-than-average displays at 12-year intervals (12 years being Jupiter's orbital period), and that 2004 is one of the favored years. The 1992 display might not qualify for comparison because the parent comet was nearby — but 1980 brought an excellent show punctuated by many fireballs, and 1968 was rated quite good despite bright moonlight."

12 posted on 08/11/2004 6:53:27 PM PDT by concentric circles
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To: lainie
Thanks for the heads-up!

We had a cool front come through here in northeast Texas this afternoon, and the seeing was great -- for about a half hour until the louds rolled in at 2:30.

In a little under 30 minutes, I counted 26 Perseids (that I could trace back to the radiant). In between meteors, it wasn't boring, because the Milky Way was spectacular. I also saw almost as many "probables" -- too fleeting or faint to trace.

FWIW, the radiant seemed to me to be nearer M31, (the great Andromeda galaxy) rather than Perseus, per se... (BTW, M31 was clearly visible to the unaided eye, and was outstanding with binoculars...)

One of the Perseids was exceptionally bright and slow; it was a bright green, traversed well over 100 degrees of arc, and broke up into three parts before vanishing. Its trail lasted for at least three minutes...

Again, thanks! Wish I had seen your post earlier; I didn't get the security light switched off until nearly 2AM... :-(

13 posted on 08/12/2004 12:48:23 AM PDT by TXnMA (It's great -- being away from Boston and back in the dark boonies of God's Country...)
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