Top: blob projected height-time (derived from the STEREO-B 195 Å images) plot with quadratic fit to the measurements. The equation of the fitted curve is h = (2.7 × 10⁴)t² + (4.1)t + 0.2, where “h” is the height (in km) and “t” is the time (in sec) from 23:03 UT. The red curve shows the GOES soft X-ray flux profile in 1−8 Å. Bottom: temporal evolution of the blob speed derived from height-time measurements. The typical error in the height estimate is four pixels (6.4″).