400 Ducrosa

Also known as (400) Ducrosa, Ducrosa

main-belt asteroid

Picture of the Day · NASA

Jupiter and Venus from Earth

2026-06-07

It was visible around the world. The sunset conjunction of Jupiter (left) and Venus (right) in 2012 was visible almost no matter where you lived on Earth. Anyone on our planet with a clear western horizon at sunset could see them. That year, a creative photographer traveled away from the town lights of Szubin, Poland to photograph a near closest approach of the two planets. The bright planets were then separated by only three degrees and his daughter struck a humorous pose. A faint red sunset still glowed in the background. Jupiter and Venus are together again this week after sunset, passing within a degree of each other about two days from today.

Key facts

Discovered by: Auguste Charlois
Discovery date: 15 March 1895
Named after: J. Ducros
Alternative designations: 1895 BU
Minor planet category: Main belt
Observation arc: 121.08 yr (44225 d)

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Article

400 Ducrosa is a typical main belt asteroid. It was discovered by Auguste Charlois on 15 March 1895 in Nice, and named for It J. Ducros a mechanic at the Nice Observatory. This minor planet is orbiting the Sun at a distance of 3.126 AU with a period of 5.527 yr and an orbital eccentricity of 0.117. The orbital plane is inclined at an angle of 10.5° to the plane of the ecliptic.

A three-dimensional model of 400 Ducrosa based on its light curve This asteroid has a B-type taxonomy, indicating it has a relatively bright geometric albedo for a carbonaceous asteroid. It has an estimated diameter of 33.66±1.6 km. Photometric measurements of the asteroid made in 2005 at the Palmer Divide Observatory showed a light curve with a rotation period of 6.87±0.01 h and a brightness variation of 0.62±0.02 in magnitude. A 2020 study found a rotation period of 6.8678±0.0001 h with a variation of 0.57±0.03 magnitude.