The dusty Coma's angular diameter is approximately 80". Using the same calculation method shown on April 30, 2026, I got an expansion speed of approximately 0.11km/sec.
Similar to Halley's comet at the same distance from the Sun.

Both Halley and 29P has low densities ( ca. 55% of water ) and most probably has a "fluffy" and highly porous structure, also described as porous "rubble piles" containing CO, CO2 and other ices.

What is distinctive about 29P are its long periods of inactivity while Halley's comet has a continuous outflow.

Sun distance (au): 6.314 Perihel 28.March 2019 Sun dist.: 5,77

Time: 20:43UT 2026-05-04 Exp.183 X 5sec
Tel: 0.254m f/5.8 ST-10XME CCD @ -25°C 0.95"/pix
Odd Trondal Obs.code 238 (Uranium). Oslo Norway.