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Small bodies

Halley · nucleus only: size, dimension and comparison

The adopted reference is about 15 km.

Approximate nucleus long axis ≈ 15 km

15 km = 15,000 m. A kilometer contains 1,000 meters.

The solid nucleus of the famous comet, without its tail.

Explore at this scale
Halley · nucleus only, interpreted illustration
Interpreted illustration · dimension stated in the fact sheet.

What does this number measure?

NASA describes Halley's nucleus with approximate dimensions of 15 × 8 km. The illustration's width represents the 15 km major axis; the coma and gas or dust tails are excluded. This length should not be compared with a comet's entire visible extent in the sky. The terrain and surface view are interpreted.

Compare the stated dimensions

The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.

Compare with Arrokoth · long axis in the explorer →

Source and limitations

Irregular nucleus, approximate dimensions; perspective does not reveal a unique three-dimensional shape. No extent of the coma or tail is included.

Interpreted nucleus of Halley, not a photograph. The horizontal major axis follows the reference of about 15 km; no coma or tail is included. Terrain, small craters and perspective remain artistic.