New observations show that the light curve of Kuiper Belt contact binary (139775) 2001 QG298 has changed substantially since the first observations in 2003. The 2010 light curve has a peak-to-peak photometric range of Δm 2010 = 0.7 ± 0.1?mag, significantly lower than in 2003, Δm 2003 = 1.14 ± 0.04?mag. This change is most simply interpreted if 2001 QG298 has an obliquity near 90°. The observed decrease in Δm is caused by a change in viewing geometry, from equator-on in 2003 to nearly 16° (the orbital angular distance covered by the object between the observations) off the equator in 2010. The 2003 and 2010 light curves have the same rotation period and appear in phase when shifted by an integer number of full rotations, also consistent with high obliquity. Based on the new 2010 light curve data, we find that 2001 QG298 has an obliquity of ε = 90° ± 30°. Current estimates of the intrinsic fraction of contact binaries in the Kuiper Belt are debiased assuming that these objects have randomly oriented spins. If, as 2001 QG298, Kuiper Belt Object contact binaries tend to have large obliquities, a larger correction is required. As a result, the abundance of contact binaries may be larger than previously believed.
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