The first gravitational microlensing event for which a planet orbiting the lens was detected around this star.
[2] By 2006, the source and lens star had moved far enough apart (as viewed from Earth) that their light could be separated.
Observations by the Hubble Space Telescope revealed that in fact the lens star was actually brighter and less red than expected, matching the expected spectra for a K dwarf of about 0.63 solar masses, more massive than the average star in the galaxy.
[3] This enables an estimate of the distance to the lens star, which puts it at around 5.8 kiloparsecs (19,000 light years) away.
The OGLE-2003-BLG-235L/MOA-2003-BLG-53L system consists of one planet as determined by the discovery team and the follow-up confirmation observations.