Sirona

Key Facts

• Categorized as a Main-belt Asteroid
• Comparable in size to the U.S. state of Delaware (71.70 km diameter)
• Not a Near Earth Object
• Not a Potentially Hazardous Object
• See orbit simulation

Overview

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

Sirona orbits the sun every 1,680 days (4.60 years), coming as close as 2.38 AU and reaching as far as 3.16 AU from the sun. Sirona is about 71.7 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Delaware.

The rotation of Sirona has been observed. It completes a rotation on its axis every 12.03 hours.

Sirona's spectral type S (Tholen) / Sk (SMASSII) indicates that it is likely to contain and .

No Close Approaches

Sirona's orbit is 1.39 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

Sirona's orbit is determined by observations dating back to Dec. 23, 1872. It was last officially observed on July 4, 2023. The IAU Minor Planet Center records 3,634 observations used to determine its orbit.

Scientists have been able to determine this object's shape:

View asteroid Sirona in 3D.

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 Sirona:

• 1 Ceres (A801 AA)
• 2 Pallas (A802 FA)
• 39 Laetitia (A856 CA)

References

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

Orbit Simulation

Sky Map

The position of Sirona 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.