(145453) 2005 RR43 (provisional designation 2005 RR43) is a trans-Neptunian object (TNO) estimated to be about 250 km in diameter.

Based on their common pattern of IR water-ice absorptions, neutral visible spectrum,[7] and the clustering of their orbital elements, the other KBOs 1995 SM55, (19308) 1996 TO66, (55636) 2002 TX300 and (120178) 2003 OP32 appear to be collisional fragments broken off the dwarf planet Haumea.

The surface is covered by water ice as attested by deep absorption at 1.5 and 2 μm in the infrared spectrum and neutral (i.e. non-red) colour.

Scattering models reveal that the observed water ice is, at least in a significant fraction, crystalline and organics, detected on the surface of many TNOs, are completely absent.

The object, together with other members of the family ((19308) 1996 TO66, (24835) 1995 SM55, (55636) 2002 TX300 and (120178) 2003 OP32), would be created from ice mantle ejected from the proto-Haumea as result of a collision with another large (around 1,660 kilometres (1,030 mi)) body.