Hyakkai

Key Facts

• Categorized as a Main-belt Asteroid
• Comparable in size to the San Francisco Bay
• Not a Near Earth Object
• Not a Potentially Hazardous Object
• See orbit simulation

Overview

Hyakkai is a mid-sized asteroid orbiting between Mars and Jupiter in the main portion of the asteroid belt. NASA JPL has not classified Hyakkai as potentially hazardous because its orbit does not bring it close to Earth.

Hyakkai orbits the sun every 1,670 days (4.57 years), coming as close as 2.31 AU and reaching as far as 3.21 AU from the sun. Based on its brightness and the way it reflects light, Hyakkai is probably between 5.352 to 11.969 kilometers in diameter, making it larger than 99% of asteroids, very roughly comparable in size to the San Francisco Bay.

The rotation of Hyakkai has been observed. It completes a rotation on its axis every 4.80 hours.

Hyakkai's spectral type None (Tholen) / S (SMASSII) indicates that it is likely to contain and .

No Close Approaches

Hyakkai's orbit is 1.31 AU from Earth's orbit at its closest point. This means that there is an extremely wide berth between this asteroid and Earth at all times.

Orbital simulations conducted by NASA JPL's CNEOS do not show any close approaches to Earth.

Images and Observations

Hyakkai's orbit is determined by observations dating back to Dec. 20, 1973. It was last officially observed on June 16, 2023. The IAU Minor Planet Center records 4,591 observations used to determine its orbit.

Accessibility and Exploration

This asteroid is not considered a viable target for human exploration by the NHATS study.

Similar Objects

These objects have orbits that share similar characteristics to the orbit of Hyakkai:

• 41 Daphne (A856 KA)
• 55 Pandora (A858 RB)
• 71 Niobe (A861 PA)

References

• JPL Small Body Database
• Mission Design
• Sky Finder Chart

Orbit Simulation

Sky Map

The position of Hyakkai is indicated by a ◯ pink circle. Note that the object may not be in your current field of view. Use the controls below to adjust position, location, and time.

Size Rendering

The above comparison is an artistic rendering that uses available data on the diameter of Hyakkai to create an approximate landscape rendering with Mount Everest in the background. This approximation is built for full-resolution desktop browsers. Shape, color, and texture of asteroid are imagined.