Saturday, November 17, 2007

15-16 November: >26 sprites, many elves and haloes!

Hi there!
This night there were storms at the north side of an intense low west of Corsica. At ~2215 UT the cameras of Pic du Midi and Lannemezan were turned on and started capturing sprites. Almost all events were captured in stereo. Corsica was once again not reacting much to commands, unfortunately. Bob Marshall from Stanford University operated his instruments as well.

Highlights are:
  • Stereo images of sprites... good parallax visible between sprites and stars. It is a bit difficult to show here as a true stereo image, given the differences in exposure, image size and aspect ratios between the two cameras, but in some images you can notice different perspectives (left is Lan, right is Pic... if only they would appear on one row...)


followed by...

  • Many elves (never seen so many before!): at least 6, and a number of haloes (mostly together with sprites) as well. The elves were very bright and were in all cases accompanied by subsequent sprites. A few cases show an elve, a halo and a sprite, with distinctive differences in height. Some elves show a hole that is not circular at all, like the first and second ones here:

same sprite by the two cameras:

The moon is visible as a bright spot to the right of the sprite. The perspective is apparent from the distance between sprite and moon.
  • The color camera recorded one or two of the sprites to be white (note that this is judged from a contrast-stretched image...) .When pulled into Image Analyzer, it shows that the green pixels were the brightest. It could be an artifact , but the colour appears completely different from all other sprites recorded last month which were definately red.
From the same huge column sprite shown above (second row), two subsequent color frames:

and another 'white' sprite:

and a normal one:

A bonus:
  • A Huge fireball streaked across the sky, captured both by Lannemezan and by Pic du Midi!

The top one is the peakhold image, the bottom one interlaced frame showing the tail. Note that the lens has no IR focus correction fitted, making the lights smeared out and also the meteor. But you get a good idea of its brightness.

Note that I added some new images for the end of October cases two posts below!

Wednesday, November 14, 2007

November sprites in Italy

We have got the sprite season only in the autumn here indeed... What about this sprite event captured a few days ago (November 9, about 20:25:02 UTC) by the SOSO system located in San Lazzaro di Savena? (Photo courtesy of Roberto Labanti)

And there was more in next days - this on 15 November: