A good title and first two paragraphs from Science Daily (note the use of quotation marks, a question mark (gasp), the reference to charged particles, and the use of the "so-called" qualifier: Scientists Pinpoint The 'Edge Of Space'.
ScienceDaily (Apr. 10, 2009) — Where does space begin? Scientists at the University of Calgary have created a new instrument that is able to track the transition between the relatively gentle winds of Earth's atmosphere and the more violent flows of charged particles in space – flows that can reach speeds well over 1000 km/hr. And they have accomplished this in unprecedented detail.But then the article sort of falls on it's face because, as BF reminds us, the exact altitude fluctuates and changes.
Data received from the U of C-designed instrument sent to space on a NASA launch from Alaska about two years ago was able to help pinpoint the so-called edge of space: the boundary between the Earth's atmosphere and outer space.