EIT and LASCO observations of August 26, 1999 JET


EIT difference images - 20:48 and 21:24 UT

EIT 195 sees jet in AR near limb at 21:24 but prior to that (beginning ~20:00) there is a dimming to the NE (filament channel?) and a behind the limb projection of a dark/bright arc somewhat South of the AR.   (Are these two features connected?  It could be that they are two ends of a filament channel, and the jet is near the center?)

The base of the jet appears to be rooted in the AR (0.99Rs, 291 deg)

The jet also appears in the 21:36 image, with its LE(?) at the edge of the f.o.v. is at (1.52 Rs, 299 deg).

LASCO image before the jet (20:26 UT)


LASCO difference images during the jet (21:26, 21:50, 22:26 UT - differenced with the 20:26 image above)

LASCO C2 sees jet appearing at 21:26 at PA~302  (measured from occulter at ~2.1Rs) extending to ~3.9 Rs

Small CME appears at 21:50 UT at same location

Width PA~287-316 (~29 degrees wide) CPA ~301 degrees

Height-time analysis on LE shows ~160 km/s (poor quality because LE was faint)

New streamer(?) appears in this location in the hours following

Several other CMEs were in progress during this period.  This small CME could be part of another event but that seems less likely because of good tag from EIT(?).

Not much is seen in C3 -- just the base of the new streamer forming above the occulting disk.