New: A NASA press release on observations of Sprites over South America (1995 June 7)
Slide #1. Black and White Image of Red Sprite
This large red sprite was observed over a thunderstorm in the Midwest; the top of the sprite is higher than 280,000 feet (85 km); the tendrils beneath the sprite are as low as 195,000 feet (60 km). The bright area beneath the sprite is an overexposure of normal lightning occurring at the thunderstorm's cloud top which is 55,000 feet high. This image was captured on the night of July 3, at 11:00 PM Central Daylight Time (CDT), using a low-light-level color television camera from an airplane flying at 43,000 feet. Universal Time (UT) is shown at the bottom of the image; 04:00:02:00 UT (on July 4 UT date) equals 11:00:02 CDT. Image credit: Geophysical Institute, University of Alaska Fairbanks.
Slide #2. Group of Sprites (with Altitude Marked)
A family of sprites captured over the Midwest on July 6 at 12:29 AM CDT (05:29 UT) using a very wide angle low-light-level, black- and-white television camera. By using triangulation of the images of the same sprites taken from the two aircraft, an accurate determination of the height and size is made. The thunderstorm's cloud top is at an altitude of about 42,000 feet and the highest parts of the sprites are at an altitude of 59 miles (95 kilometers). In this image Universal Time is shown in the upper left; other flight data is shown at the bottom. Image credit: Geophysical Institute, University of Alaska Fairbanks.
Slide #3 Black and White Image of a Blue Jet
This large blue jet, shooting upwards from a thunderstorm's top, reached an upper altitude of about 130,000 feet (40 km). These jets have been reported in anecdotal accounts over the last century. This image and other images of jets captured on the evening of June 30 are the first ever recorded. The jets appear to move at speeds of 45,000 to 223,000 miles per hour (20 to 100 km per sec). This example was captured with a very wide angle low-light, black-and-white television camera flying over eastern Arkansas at 10:03 PM CDT (03:03 UT on UT date July 1). Universal Time is shown in the upper left; other flight data is shown at the bottom. Image credit: Geophysical Institute, University of Alaska Fairbanks.
To understand more about sprites, how to look for them, current research, and more, click here.
There are some very interesting pictures and accounts of sprites and jets on this page about Shuttle Lightning Observation.