2012 BX34

 is a small Aten asteroid that made one of the closest recorded asteroid close approaches of Earth on 27 January 2012. It passed within 0.0004371 AU of Earth during its closest approach at 15:25 GMT. measures around 8 m across; if it had impacted in 2012, it would have been too small to pass through Earth's atmosphere intact.

During its 2012 close approach to Earth, had a brightest apparent magnitude of about 13.9, making it about as bright as the dwarf planet Pluto. By 25 February 2012, it had dimmed to magnitude 30. During its close approach of 0.0246 AU on 28 January 2014, it will only reach a magnitude of about 23. has been observed in more detail using radar astronomy.