How closely packed are Jupiter’s Trojan asteroids?

The quantity density of asteroids in the principle belt about 10 occasions greater than that of Jupiter’s Trojan asteroids.

How intently packed are Jupiter’s Trojan asteroids in comparison with the density of the principle belt?

Doug Kaupa
Council Bluffs, Iowa

Jupiter’s Trojans are asteroids that share the gas giant’s orbit across the Solar, clustering at one among two Lagrange points within the Jupiter-Solar system (L4 or L5, 60° forward of or behind Jupiter in its orbit, respectively).

It seems that main-belt asteroids (MBAs) and Trojan asteroids occupy a comparatively comparable quantity in space. The majority of MBAs lie between 2.1 and three.3 AU from the Solar, whereas Jupiter’s Trojans are 5 to five.3 AU from our star. Most of those our bodies (in each teams) have orbital inclinations lower than 30°.

You possibly can approximate the amount these asteroids occupy utilizing rings. So, image a torus with a round cross-section, with the inside and outer diameter being the inside and outer extents of the orbits simply given, in order that the amount every occupies is 61 AU³ and 58 AU³, respectively, for MBAs and Trojans. (One AU, or astronomical unit, is the typical Earth-Solar distance of 93 million miles [150 million kilometers]. So, 1 AU³ = 8 x 10²³ miles³ [2.7 x 10²⁴ km³].)

There are about 10⁸ MBAs bigger than about 330 ft (100 meters) in diameter, and about 10⁷ Trojans of this similar dimension. That makes the amount density of asteroids in the principle belt about 10 occasions greater than that of Jupiter’s Trojan asteroids.

Nonetheless, MBAs are arduous to come back by within the vastness of space. A sphere with a radius of about 249,000 miles (400,000 km) incorporates just one MBA bigger than 330 ft (100 m) in diameter.

Simone Marchi
Workers Scientist, Southwest Analysis Institute, Boulder, Colorado