Meteoroid Streams Sculpt the Inner Zodiacal Cloud

The abundance of dust encountered by Parker Solar Probe in the inner zodiacal cloud exhibits persistent variability of ∼50% on timescales of its ∼100 day orbits. Spatial variations in the zodiacal cloud of ∼10 5 km, comparable to meteoroid stream cross sections, can be related to temporal variations of ∼100 days that evolve via Poynting–Robertson drag. Such density modulations manifest as only a few percent variation in line-of-sight integrated brightness, making them challenging to detect via remote imaging. We discuss multiple possible source mechanisms for this variability and propose that the presence of dense meteoroid streams that intersect and collide with the zodiacal cloud can produce the observed small-scale density modulations. Cometary disruptions may be prominent in producing these streams that collisionally interact with the zodiacal cloud.