3360 Syrinx

3360 Syrinx is an Apollo and Mars crosser asteroid discovered in 1981. It approaches Earth to within three times in the 21st century: in 2039, 40 million km in 2070, and in 2085.
On 20 September 2012, it closely encountered Earth at a distance of, peaking in brightness at an apparent magnitude of 17.0. In opposition on 23 November 2012, it brightened to magnitude 16.0.
It is a member of the Alinda group of asteroids with a 3:1 resonance with Jupiter that has excited the eccentricity of the orbit over the eons. As an Alinda asteroid it makes approaches to Jupiter, Earth, and Venus.
For a time, it was the lowest numbered asteroid that had not been named. In November 2006, this distinction passed to 3708 Socus, and in May 2021 to (4596) 1981 QB.