Rilles extend about 100 km northwest of Gerard

Feature Profile & Selenographic Data

Feature type

crater

Coordinates

44.54° N · 80.51° W

Diameter

98.78 km

IAU approval

1935/01/01 00:00:00

LAC quadrangle

LAC-22 · Lavoisier

Geological Chronicle

Gerard lies along the western edge of Oceanus Procellarum, near the Moon’s northwest limb. From Earth it appears strongly foreshortened, which hinders observation. Von Braun is to the north-northwest and Bunsen to the northeast.

The rim is worn and eroded, with some locations nearly obliterated and others distorted. Its northern half has outward bulges to the northeast, north and northwest. The floor is rough in places, with small and tiny craters along it and the eastern rim.

Northwest of Gerard, Gerard Q Inner lies within Gerard Q Outer, and its eastern floor is covered by dark-hued basaltic lava. The nearby Rimae Gerard system extends about 100 kilometers. The floor of Gerard Q Inner is fractured, as are floors in the region such as von Braun and Bunsen.

Chronology & Exploration

1. Undated Foreshortened views hinder observation

   Gerard’s position near the northwest limb makes it appear strongly foreshortened from Earth, hindering observation.

2. Undated Rimae Gerard length described

   The nearby system of rilles extends about 100 kilometers.

3. Undated Crater named for Alexander Gerard

   The registry gives the crater’s name origin as Alexander Gerard, a Scottish explorer.

Scientific Sources & References

• International Astronomical Union Gazetteer — Registry record for the crater’s identity, coordinates, diameter, quadrangle and name origin.
• Wikipedia: Gerard (crater) — Localized source text for the crater’s location, viewing conditions, rim and floor morphology, nearby rilles and basaltic material.

Name Origin

Alexander; Scottish explorer (1792-1839).