Totality - The fastest 4 minutes and 28 seconds I have ever experienced
Magnitude
The magnitude of an eclipse, or the ratio of the angular diameter of the Moon to the angular diameter of the Sun, must be one or greater for a total eclipse to occur. The Moon was near perigee (the closest point in its orbit to Earth) during this eclipse. As it was closer than average, it appeared larger than its average size in the sky. The Sun had an angular diameter of 31'56" at the moment of greatest eclipse. As the magnitude of this eclipse at that time was 1.0566, the angular diameter of the Moon was 1.0566 times that of the Sun, or 33'44". This gave the eclipse a wider path of totality and more maximum time in totality (4 min 28 s) compared to the total eclipse in 2017 (2 min 40 s), which had a magnitude of 1.0306.
Solar prominences
The eclipse occurred around the solar maximum, a period of greatest solar activity in the Sun's 11-year solar cycle, and it was anticipated that solar prominences would be visible during totality. Many observers reported seeing solar prominences during the event. Most plainly visible to the naked eye was a very bright red point of light near the lowest portion of the Sun's disk, which on telescopic views and photographs showed as a tent-shaped angular structure. The red and pink hues were the result of hydrogen and helium plasma being thrown up in broad arcs but never leaving the sun's atmosphere. Telescopic photographs revealed the western limb having several smaller, irregular shapes, of which one large, ragged shape appeared disconnected from the Sun's surface on one side. Several smaller prominences were also visible on the eastern limb, though because of the eclipse's relatively high magnitude, prominences on both limbs could not be viewed at the same time. These shapes correlate in detail with the NASA Solar Dynamics Observatory solar telescope images taken in space at the same as the earthbound eclipse, and with images from the ground-based National Solar Observatory GONG telescope in Cerro Tololo, Chile.
Shadow bands
The shadow bands phenomenon was observed and documented in some locations with clear skies. Attempts to observe and record shadow bands on the ground were disappointed in many areas of totality by the phenomenon not appearing in the event, perhaps having been washed out by the diffuse illumination of cloudy skies in various locations.